300 words HCA240 - Achiever Papers

Individual
Lifestyle or Medication? Resource: Human Diseases: A Systemic Approach
Select a gastrointestinal disease mentioned in Ch. 9 of Human Diseases: A Systemic Approach that can be prevented or controlled by changes in lifestyle.
Write a 300- to 350-word paper describing the chosen disease and include the following:
• Describe the lifestyle changes individuals can implement to prevent or control the disease.
• Explain the factors that might make the lifestyle changes difficult to accomplish.
• Propose strategies to overcome those factors.
• Explain why you would choose lifestyle change or prescription medication if the choices were available for a condition you were diagnosed with.
Include at least two sources other than Human Diseases: A Systemic Approach.
Format your paper consistent with APA guidelines.
Post your paper as an attachment.

Diseases of the
Gastrointestinal System

C H A P T E R

Learning Objectives

After studying this chapter, you should be able to

■ Describe the normal structure and function of the digestive tract

■ Describe the key characteristics of major diseases of the digestive tract

■ Name the diagnostic tests for diseases of the digestive tract

■ Explain the etiology of gastrointestinal diseases

■ Describe the treatment options for diseases of the digestive tract

■ Describe the normal structure and function of the liver, gallbladder,
and pancreas

■ Describe the key characteristics of major diseases of the liver,
gallbladder, and pancreas

■ Name the diagnostic tests for diseases of the liver, gallbladder, and
pancreas

■ Explain the etiology of liver, gallbladder, and pancreas diseases

■ Describe the treatment options for diseases of the liver, gallbladder,
and pancreas

■ Describe age-related diseases of the digestive system

Cancer of the colon or rectum
is the second leading cause of
cancer-related death in the
United States.

Fact:The American Cancer So-
ciety estimates that each year
56,000 Americans will die of
colorectal cancer, second only
to lung cancer.

Fact or
Fiction?

C. difficile is a major cause of
pseudomembranous colitis and
antibiotic-associated diarrhea.
(Courtesy of the CDC/Dr. Gilda
Jones, 1980)

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and Mary Lou Mulvihill, Ph.D. Published by Prentice Hall. Copyright © 2010 by Pearson Education, Inc.

199

Dysentery

Diseases of the digestive system include common ailments fa-miliar to nearly everyone. Some are minor annoyances; oth-ers are serious, life-threatening diseases. The impact of di-gestive system diseases is undeniable. During the American
Civil War, 81,360 soldiers died from dysentery, while 93,443 were
killed in combat. Even today, 18,000 cases of bacillary dysentery
occur annually in the United States. Despite modern medical diagno-
sis and treatment, cancer of the pancreas, colon, and liver remain
deadly, and worldwide, dysentery remains a leading cause of death
among children.

Disease Chronicle

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200 ■ Chapter Nine Diseases of the Gastrointestinal System

The Gastrointestinal System

The digestive system consists of a digestive tract
through which food passes and accessory or-
gans that assist the digestive process. The di-
gestive tract begins at the mouth and includes
the pharynx, esophagus, stomach, small intes-
tine, and large intestine. The accessory organs
include the liver, gallbladder, and pancreas
(Figure 9–1 �).

Digestion begins in the mouth with chewing,
the mechanical breakdown of food. Salivation,
the secretion of saliva, moistens the food and
provides an enzyme for initial digestion of
starch. The food is then swallowed and passes
through the pharynx, or throat, and into the
esophagus.

The moistened food moves down the esopha-
gus to the stomach. A sphincter muscle at the
juncture of the esophagus and stomach pre-
vents regurgitation while digestion continues.
The stomach secretes gastric juice that con-
tains enzymes, biological catalysts that act on
protein. Gastric juice also contains hydrochlo-
ric acid, which activates these enzymes. The
acidic gastric contents would be irritating to the
stomach lining if the lining were not protected
by a thick covering of mucus. A great deal of
moistening and mixing occurs within the stom-
ach. The moistened, mixed, and acidic food is
called chyme.

Chyme passes from the stomach into the
small intestine through a sphincter muscle, the
pyloric sphincter. This sphincter is closed until it
receives nerve and hormonal signals to relax
and open. Chyme is propelled along its course
by rhythmical, smooth muscle contractions of
the intestinal wall called peristalsis.

Most digestion occurs in the first part of the
small intestine, the duodenum. Intestinal secre-
tions contain mucus and digestive enzymes,
which enter by means of the pancreatic duct
from the pancreas. The pancreas secretes en-
zymes that digest protein, lipid, and carbohy-
drate. It also secretes an alkaline solution for
the neutralization of acid carried into the small
intestine from the stomach.

Bile, secreted by the liver and stored in the
gallbladder, enters the duodenum through the

▼ common bile duct. Bile is not an enzyme but an
emulsifier, a substance that reduces large fat
droplets into much smaller fat droplets, en-
abling the lipid enzymes to digest fat into small,
absorbable units.

When digestion is complete, nutrients such
as sugars and amino acids are absorbed into
blood capillaries and lymph vessels in the in-
testinal wall. The inner surface of the small in-
testine is arranged to provide the greatest
amount of surface area possible for digestion
and absorption. This mucosal surface contains
numerous fingerlike projections called villi,
each of which contains capillaries and lymph
vessels for absorption (Figure 9–2 �).

Material not digested passes into the large in-
testine, or colon. The first part of the colon is the
cecum, to which the appendix, a fingerlike mass
of lymphatic tissue, is attached. Water and min-
erals are absorbed from the large intestine, and
the remaining matter is excreted as feces.

In this chapter, the diseases of each part of
the digestive system are described. These in-
clude diseases of the mouth, esophagus, stom-
ach, small and large intestines, pancreas, liver,
and gallbladder.

General Disorders
of the Digestive Tract

General disorders of the digestive system, such
as vomiting, diarrhea, constipation, and hemor-
rhoids are not diagnoses in themselves. These
common disorders are signs and symptoms and
could indicate the presence of any number of
different diseases. The physiologic basis and
significance of each disorder is described
briefly.

Vomiting
Vomiting is a protective mechanism, a re-
sponse to the presence of an irritant or infec-
tion, a distention, or a blockage. These stimu-
late sensory nerve fibers, and the message is
conveyed to the vomiting center in the medulla
of the brain. Motor impulses then stimulate the

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Chapter Nine Diseases of the Gastrointestinal System ■ 20

Parotid gland

Parotid duct

Pharynx

Esophagus

Tongue

Sublingual
Submandibular

Salivary
glands

Fundus of
stomach

Spleen

Body of stomach

Left lobe
of liver

Pancreas

Left colic flexure

Transverse colon

Descending colon

Small intestines
(duodenum, jejunum
and ileum)

Rectum

Right lobe of liver

Gall bladder

Pylorus

Right colic flexure

Ascending colon

Cecum

Appendix

Figure 9–1 � The gastro-
intestinal system.

diaphragm and abdominal muscles; contrac-
tion of these muscles squeezes the stomach.
The sphincter at the base of the esophagus is
opened, and the gastric contents are regur-
gitated. A feeling of nausea often precedes vom-

iting. The cause of the nausea may be factors
other than a gastric or intestinal irritant. Mo-
tion sickness produces this effect. A very un-
pleasant smell or sight can cause nausea with
possible subsequent vomiting.

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Mesenteric artery
and vein

Mesentery

Plica

Visceral
peritoneum
(serosa)

Muscularis
externa

Submucosa

Mucosa

Mucosal epithelium

Submucosal gland

Submucosal plexus

Mucosal glands

Artery and vein

Lymphatic vessel

Circular
muscle layer

Longitudinal
muscle layer

Myenteric plexus

Villi

Muscularis mucosae

Figure 9–2 � Mucosal surface of the small intestine.

202 ■ Chapter Nine Diseases of the Gastrointestinal System

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and Mary Lou Mulvihill, Ph.D. Published by Prentice Hall. Copyright © 2010 by Pearson Education, Inc.

Diarrhea
Diarrhea is the frequent passage of watery
stools and results when the contents of the
small intestine are rushed through the large in-
testine. It was stated earlier that the main func-
tion of the large intestine is to reabsorb water
and minerals. In an episode of diarrhea, there
is no time to reabsorb water because the
smooth muscle in the walls of the intestine is so
stimulated that peristalsis is intensified. Anxi-
ety and stress can trigger this increased motil-
ity of the large intestine. Intestinal infections
and food poisoning also can increase intestinal
motility or impair water absorption by mucosal
cells.

Constipation
Constipation is the inability to eliminate feces
from the colon and results when feces become
hard and dry. Poor habits of elimination, dehy-
dration, and low-fiber diets may cause constipa-
tion. Defecation should be allowed to occur
when the defecation reflexes are strong; other-
wise feces remain in the colon too long, exces-
sive water reabsorption occurs, and the feces
become dry, making elimination difficult. A diet
containing adequate amounts of fiber aids elim-
ination by providing bulk, which stimulates in-
testinal motility. Fiber is obtained from fresh
fruits, vegetables, and cereals. This chapter will
discuss several disorders and diseases of the di-
gestive system that cause constipation.

Hemorrhoids
Hemorrhoids are varicose veins in the lining of
the rectum near the anus. Hemorrhoids may be
internal or external. A physician can observe in-
ternal hemorrhoids with a proctoscope, a hollow
tube with a lighted end. External hemorrhoids
can be seen with a handheld mirror and appear
blue because of decreased circulation; they can
become red and tender if inflamed. Causes of
hemorrhoids include heredity, poor dietary
habits, inadequate fiber, overuse of laxatives,
and lack of exercise. Straining to have a bowel
movement can cause bleeding or cause the he-
morrhoid to prolapse, or come through the anal

Chapter Nine Diseases of the Gastrointestinal System ■ 20

opening. Hemorrhoids frequently develop dur-
ing pregnancy because of pressure from an en-
larged uterus. Treatment includes adding fiber
and water to the diet and stool softeners to re-
duce straining and subsequent inflammation.
Medicated suppositories and anorectal creams
relieve pain and reduce inflammation.

Diseases of the Mouth

Complete coverage of diseases of the mouth is
beyond the scope of this book. This chapter fo-
cuses instead on the major oral inflammatory
diseases and neoplasms. Diseases of the mouth
can adversely affect the ability to taste, chew,
moisten, and swallow food.

Oral Inflammation
Oral inflammation, or stomatitis, refers to a
widespread inflammation of oral tissue. De-
pending on the cause, stomatitis may appear as
patches, ulcers, redness, bleeding, or necrosis.
Stomatitis can be caused by local infection of
the mouth with bacteria, viruses, or fungi, or it
may be a sign of a systemic infection.

Streptococci, spread in salivary and respira-
tory droplets, are a common cause of oral and
throat bacterial infections, resulting in red,
swollen mucosa. Bacteria also cause canker
sores, small circular lesions with a red border.
These painful lesions heal without scars after a
week. Neisseria gonorrhea, the cause of the sex-
ually transmitted disease gonorrhea, causes
painful ulcerations in the mouth and throat.
Also sexually transmitted, Treponema pallidum
causes syphilis, which causes oral chancres
and ulcerations. These bacterial infections are
treated with antibiotics.

Herpes simplex is a common cause of oral
virus infections. Transmitted by oral–genital
contact, herpes simplex type 2 causes vesicles
that rupture to form ulcers. These lesions can
appear inside and outside the mouth. Herpes
simplex type 1 can also be acquired from sali-
vary droplets. Pain makes eating, drinking, and
swallowing difficult. The symptoms typically

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and Mary Lou Mulvihill, Ph.D. Published by Prentice Hall. Copyright © 2010 by Pearson Education, Inc.

subside within two weeks when the viruses
move from the area to nerve tissue known as
ganglia. The infection can be reactivated follow-
ing stressful events or suppression of immune
function. Treatment is aimed at reducing in-
flammation and pain with systemic anti-inflam-
matory and analgesic medications or topical
anesthetics.

The fungus Candida albicans is present in
the mouth in low levels normally, but can grow
excessively in normal newborns and those with
immune deficiencies or following long courses of
antibiotic or corticosteroid treatment. The fun-
gal overgrowth, called candidiasis or thrush,
forms painless white patches that resemble
cheese curds. Removing the white patches
leaves a raw, damaged mucosal surface. Can-
didiasis of the esophagus causes throat pain
and difficulty swallowing. Antibiotics and antivi-
ral medications are not effective treatments for
fungal infections (see Chapter 3). Oral candidia-
sis is treated with oral antifungal agents flu-
conazole, nystatin, or clotrimazole.

Cancer of the Mouth
The most common form of oral cancer is squa-
mous cell carcinoma. Most of these cancers ap-
pear on the floor of the mouth, tongue, and
lower lip. An aggressive form of the cancer oc-
curs on the upper lip. Mouth and throat cancer
ranks eleventh among the leading causes of
cancer death worldwide. While the causes re-
main unknown, it is clear that tobacco, smoke-
less tobacco, and alcohol use are major risk fac-
tors, and it appears that use of alcohol and
tobacco in combination increases the risk.
Treatment for lip and tongue cancer includes
surgical removal. Radiation therapy may be
used to treat local cancers on the floor of the
mouth. See Chapter 4 for oral cancer specifics.

Diseases of the Esophagus

The function of the esophagus is the controlled
passage of food to the stomach. Esophageal dis-
ease manifests itself as dysphagia, or difficult or
painful swallowing.

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204 ■ Chapter Nine Diseases of the Gastrointestinal System

Cancer of the Esophagus
Cancer of the esophagus occurs most commonly
in men over 60 and is nearly always fatal. The
disease ranks sixth among leading causes of
cancer death worldwide but is most common in
Japan, China, the Middle East, and parts of
South Africa. Like mouth cancer, tobacco and
alcohol use are major risk factors. The cancer
narrows the esophageal lumen, causing the
principal symptom, dysphagia. The obstruction
causes vomiting, a bad taste in the mouth, and
bad breath. Esophageal cancer is accompanied
by weight loss because of the inability to eat. Di-
agnosis includes x-ray with barium swallow to
study motility and functional defects. The can-
cer frequently metastasizes into adjacent or-
gans, usually the lungs and liver, and to remote
sites through the lymph vessels before it is de-
tected. Because of early metastasis, the progno-
sis for esophageal cancer is poor. See Chapter 4
for further information on esophageal cancer.

Esophageal Varices
Varicose veins that develop in the esophagus
are called esophageal varices. Cirrhosis of the
liver is the chief cause of esophageal varices.
Cirrhosis impairs blood flow through the liver,
which elevates pressure in the veins of the ab-
domen and elsewhere, including the esophagus.
The increased venous pressure causes the
esophageal veins to dilate and become knotty.
The most serious danger in esophageal varices
is hemorrhage. Bleeding esophageal varices re-
quire emergency treatment. Diagnosis usually
requires endoscopy. Infusion of vasopressin
may reduce bleeding, or bleeding can be
stopped with pressure on the varices by insert-
ing a Minnesota or Sengstaken-Blakemore tube.
These are temporary measures: Surgical bypass
of the portal vein to systemic circulation may re-
duce pressure in the veins and thus stop bleed-
ing, but it will not repair liver damage and ulti-
mately will not improve the prognosis.

Esophagitis and GERD
Esophagitis, inflammation of the esophagus,
causes burning chest pains, “heartburn,” which

which strengthen the cardiac sphincter and re-
duce reflux after eating. Patients should avoid
irritants such as spicy foods and caffeine,
should take frequent small meals, and, if obese,
should lose weight. Surgery may be required to
correct the structural defect, but hiatal hernias
tend to recur following surgery.

Diseases of the

Stomach

The stomach is well adapted for storing and
mixing food with acid and enzymes. Alterations
in the stomach lining or malignancies can cause
painful and sometimes serious disease.

Gastritis
Acute gastritis is an inflammation of the stom-
ach frequently accompanied by vomiting of
blood. Acute gastritis is caused by irritants

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Chapter Nine Diseases of the Gastrointestinal System ■ 205

Esophagus

Stomach
protruding up
through
diaphragm

Stomach

Figure 9–3 � Hiatal hernia. (©K. Somerville/Custom Medical
Stock Photo)

can resemble the pain of heart disease. The pain
may follow eating or drinking, and some vomit-
ing of blood may occur. The most common trig-
ger of esophagitis is a reflux, a backflow of the
acid contents of the stomach. The condition is
known as gastroesophageal reflux disease or GERD.
GERD may be caused by an incompetent cardiac
sphincter, which normally prevents stomach
contents from ascending the esophagus. Other
causes include hiatal hernia and medications
that compromise the sphincter or induce excess
acid secretion. The incidence of GERD increases
with age, which suggests that age-related
changes occur in the sphincter. Whatever the
cause, regurgitated stomach acid irritates the
lining of the esophagus and stimulates an in-
flammatory response. Diagnosis is based on
history, signs, symptoms, as well as barium flu-
oroscopy, measure of esophageal pH, or en-
doscopy. Risk factors for GERD include old age,
obesity, and pregnancy. Treatment includes a
nonirritating diet, antacids, and acid-reducing
medications. Frequent, small meals are recom-
mended. Painful symptoms frequently occur at
night while the body lies prone and relaxed;
thus patients are advised to sleep with head ele-
vated and to avoid eating 2 to 3 hours before
sleeping. Alcohol is an irritant to the inflamed
mucosal lining and should be avoided.

Hiatal Hernia
A hernia is the protrusion of part of an organ
through a muscular wall or body opening. A
hiatal hernia is the protrusion of part of the
stomach through the diaphragm at the point
where the esophagus joins the stomach. The
condition is caused by either a congenital defect
in the diaphragm or by increased intraabdomi-
nal pressure associated with obesity. Figure
9–3 � shows this condition. Indigestion and
heartburn may occur after eating; shortness of
breath may also occur. Diagnosis is based on a
chest x-ray that may show air behind the heart,
or a barium radiograph that can show a bulge
at lower esophagus, or endoscopy to visualize
the hernia and rule out cancer or varices. The
aim of treatment is to reduce symptoms. The
most effective treatment is cholinergic drugs,

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206 ■ Chapter Nine Diseases of the Gastrointestinal System

such as aspirin, excessive coffee, tobacco, alco-
hol, or infection. Acute alcoholism is a major
cause of hemorrhagic gastritis. Chronic alcohol
use stimulates acid secretion, which irritates
the mucosa. Gastroscopy with biopsy is ex-
tremely valuable in diagnosing this disease. A
camera may be attached to the gastroscope, and
the entire inner stomach is photographed.
Treatment includes avoiding the aforemen-
tioned irritants and treating infections. Medical
treatment includes cimetidine, which blocks
gastric secretion. If bleeding is involved, surgery
may be required.

Chronic Atrophic Gastritis
Chronic atrophic gastritis is a degenerative con-
dition in which the stomach lining does not se-
crete intrinsic factor and hydrochloric acid. In-
trinsic factor is required for absorption of
vitamin B12, and hydrochloric acid aids protein
digestion. Chronic atrophic gastritis may be
caused by stomach cancer, chronic alcoholism,
or chronic exposure to certain irritants such as
alcohol, aspirin, and certain foods. The term
atrophic (wasting) suggests that little can be
done to treat this disease. The underlying dis-
eases or causes should be eliminated.

Peptic Ulcers
Ulcers are lesions of any body surface where
necrotic tissue forms as a result of inflammation
and is sloughed off, leaving a hole. Ulcers of the
stomach and small intestine are termed peptic
ulcers. Ulcers of the stomach are called gastric ul-
cers, and those of the small intestine are called
duodenal ulcers. Approximately 80% of peptic ul-
cers are duodenal ulcers and occur most fre-
quently in men between ages 20 and 50. Figure
9–4� shows common sites of peptic ulcers.

Peptic ulcers have three main causes, includ-
ing infection with Helicobacter pylori, use of non-
steroidal anti-inflammatory drugs, and an in-
herited disorder of acid hypersecretion. Because
hydrochloric acid secretion is under nerve and
hormonal control, stressful situations can trig-
ger or exacerbate ulcers. Gastric contents con-
tribute to ulcer formation in all cases. The ul-
cers are caused, in part, by pepsin, a proteolytic
enzyme secreted by the stomach. Hydrochloric
acid of the stomach and intestinal juice, includ-
ing bile, which is regurgitated through the py-
loric sphincter, also irritate the gastric mucosa.
Irritated and inflamed mucous membrane may
become necrotic, leaving a hole.

▲ Normal mucosa showing openings of gastric glands.
(© C. Abrahams, M.D./Custom Medical Stock Photo)

SIDE by SIDE ■ Gastric Ulcer

▲ Superficial gastric ulcer in the stomach lining.

Chapter Nine Diseases of the Gastrointestinal System ■ 20

Gastric juices are
released into the
stomach

Gastric juices
(acidic)

Duodenal
ulcer

Gastric
ulcer

Acid secretions further
break down the lining
of the stomach,
forming an ulcer

H. pylori infection
induces inflammation
in mucosa

Figure 9–4 � Peptic ulcer disease (PUD).

Heartburn and indigestion are frequently the
first signs of an ulcer. The ulcer pain is caused
by the action of hydrochloric acid on the ex-
posed surface of the lesion. The muscular con-
tractions of peristalsis also intensify the pain.
Symptoms of gastric ulcer include nausea, vom-
iting, abdominal pain, and, occasionally, mas-
sive gastrointestinal bleeding.

A potential complication of any ulcer is hem-
orrhage; severe hemorrhage may lead to shock.
It is possible for a large artery at the base of the
ulcer to rupture as the lesion erodes deeper into
underlying tissues. Bleeding from the ulcer may
appear as hematemesis or bloody vomitus, or the

blood may appear in stools, where it gives the
stools a dark, tarry appearance, referred to as
melena. A serious ulcer complication is per-
foration. If an ulcer perforates—that is, breaks
through the intestinal or gastric wall—there is
sudden and intense abdominal pain. Peritonitis,
inflammation of the lining of the abdominal cav-
ity, usually results when the digestive contents
enter the cavity, because this material contains
numerous bacteria. Surgical repair of the perfo-
ration is required immediately. Obstruction of
the gastrointestinal tract can result from an
ulcer and the scar tissue surrounding it. Ob-
struction occurs most frequently in a narrow

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208 ■ Chapter Nine Diseases of the Gastrointestinal System

area of the stomach, near the pyloric sphincter.
Ulcer pain can cause the sphincter to go into
spasm, also resulting in obstruction.

Diagnosis is based on an upper gastrointesti-
nal barium swallow, an x-ray, detection of blood
in stools, blood tests to determine elevated lev-
els of white blood cells, and gastric content
analysis. The main objectives of treatment for
peptic ulcer disease are to promote healing, pre-
vent complications and recurrences, and pro-
vide pain relief. Acid reducers, such as omepra-
zole or ranitidine, are more effective for peptic
ulcers than are antacids and mucosal barriers
such as sucraflate. However, antibiotic therapy
in combination with acid reducers is required to
eradicate H. pylori and to reduce the rate of
ulcer relapse. If the ulcer is stress or tension re-
lated, certain changes in lifestyle or approach to
stress might be beneficial.

Gastroenteritis and Food Poisoning
Gastroenteritis is an inflammation of the stom-
ach and intestines. Symptoms include anorexia,
nausea, vomiting, and diarrhea. The onset may
be abrupt, with rapid loss of fluid and elec-
trolytes. Possible causes are bacterial or viral
infection, chemical toxins, lactose intolerance,
or other food allergy, although the actual cause
is not always clear. Treatment replaces fluid
and nutritional requirements, including the lost
salts. Antispasmodic medications can control
the vomiting and diarrhea.

Food contaminated with human or animal
feces may carry microorganisms that cause gas-
troenteritis and food poisoning. Escherichia coli
is a normal inhabitant of human or animal in-
testines. Certain strains may cause disease, like
traveler’s diarrhea, or more serious diseases,
like hemolytic uremic syndrome, in which toxins
cause potentially fatal shutdown of the kidneys.
To prevent infection, cook meat thoroughly and
practice good hygiene in the kitchen.

One of the common forms of food poisoning
is caused by the bacterium Salmonella. These
bacteria invade the intestinal mucosa and
cause sudden, colicky abdominal pain, nausea,
vomiting, and sometimes bloody diarrhea and
fever that begins approximately 6 to 48 hours
after eating contaminated food and lasts up to

2 weeks. A stool culture can identify the bac-
teria. Salmonella food poisoning (salmonellosis)
is associated with contaminated eggs and poul-
try, but most any food may harbor the bacteria.
Treatment usually consists of replenishing
water, electrolytes, and nutrients. Elderly indi-
viduals, young children, and immunocompro-
mised people are at risk of developing serious
infection, and they may require more interven-
tion, including a short course of antibiotics and
antidiarrheal medications.

Cancer of the Stomach
Cancer of the stomach may be a large mass pro-
jecting into the lumen of the stomach, or it may
invade the stomach wall, causing it to thicken.
As the tumor grows, the lumen is narrowed to
the point of obstruction. The remainder of the
stomach becomes extremely dilated due to the
blockage, and pain results from pressure on
nerve endings. Infection frequently accompanies
cancer, which causes additional pain. Because
pain is not an early sign, carcinoma of the stom-
ach may be very advanced before it is detected.
It may even have spread to the liver and sur-
rounding organs through the lymph and blood
vessels. Early symptoms are vague and include
loss of appetite, heartburn, and general stomach
distress. Blood may be vomited or appear in the
feces. Pernicious anemia generally accompanies
cancer of the stomach, because the gastric mu-
cosa fails to secrete intrinsic factor. The etiology
of this malignancy is not known, but current re-
search suggests an association with the con-
sumption of preserved, salted, cured foods and a
diet low in fresh fruits and vegetables. The inci-
dence of stomach cancer in the United States
has dropped dramatically over the past 30 years;
it has become an uncommon disease and ac-
counts for less than 1% of all cancers. Today the
mortality rate for stomach cancer is about 6 per
100,000 men. Stomach cancer is the ninth lead-
ing cause of cancer death in men, and is more
prevalent among men over age 40 than among
women. Stomach cancer is not among the ten
leading causes of cancer death among women.

Gastric analysis by means of a stomach tube
demonstrates the absence of hydrochloric acid,
or achlorhydria. Biopsy of any lesions seen

Chapter Nine Diseases of the Gastrointestinal System ■ 209

through the gastroscope is an essential diag-
nostic procedure for carcinoma of the stomach.

H. pylori infection appears to increase the risk
for stomach cancer, probably through its damag-
ing effects on the mucosal cells. Good prognosis
for this disease depends on early detection and
treatment. See Chapter 4 for more information.

Diseases of the Intestines

The small intestine is the site of most of the di-
gestion and absorption that occurs in the diges-
tive tract, while the large intestine absorbs re-
maining water and stores and concentrates the
feces. Diseases in these areas may manifest
themselves as diarrhea, constipation, changes
in stool characteristics, or secondary diseases
that arise as a result of poor nutrition.

Appendicitis
Appendicitis is an acute and painful inflamma-
tion of the appendix. Appendicitis can occur at
any age, but it is more common for males before
puberty to age 25. The wormlike shape of the
appendix and its location on the cecum make it
a trap for fecal material, which contains bacte-
ria, particularly Escherichia coli. Figure 9–5 � il-
lustrates this potential site of infection. Ob-
struction with fecal material and infections
cause the appendix to become swollen, red, and
covered with an inflammatory exudate. Because
the swelling interferes with circulation to the
appendix, it is possible for gangrene to develop.

▼

The appendix then becomes green and black.
The wall of the appendix can become thin and
rupture, spilling fecal material into the peri-
toneal cavity, causing peritonitis. Before antibi-
otic treatment, peritonitis was almost always
fatal. Rupture of the appendix tends to give re-
lief from the pain, which is very misleading.

Diagnosis depends on physical exam. The
pain of appendicitis is not always typical, but it
often begins in the middle of the abdomen and
shifts to the lower right quadrant. Patients may
walk or lie bent over and draw the right leg up to
the abdomen to seek pain relief. Other diagnos-
tic signs and symptoms include nausea, vomit-
ing, fever of between 99°F and 102°F, and
elevated white blood cell count. Untreated ap-
pendicitis is fatal, and surgery must be per-
formed before rupture occurs.

Malabsorption Syndrome
The inability to absorb fat or some other sub-
stance from the small intestine is known as
malabsorption syndrome. Signs and symptoms of
malnutrition occur, including lack of energy and
inability to maintain weight. Because fat cannot
be absorbed from the intestine, it passes into
the feces, and the result is unformed, fatty, pale
stools that have a foul odor. The fat content
causes the stools to float.

Although defective mucosal cells can cause
the abnormal absorption, other diseases can re-
sult in secondary malabsorption syndrome. A
diseased pancreas or blocked pancreatic duct
deprives the small intestine of lipase. In the

Ileocecal valve

Cecum
Appendix

Large intestine

Opening into appendix

Small intestine
(ileum)

Figure 9–5 � Appendix attached to cecum into
which the small intestine empties.

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210 ■ Chapter Nine Diseases of the Gastrointestinal System

absence of lipase, fat is not digested and cannot
be absorbed. Inadequate bile secretion, due to
liver disease or a blocked bile duct, also pre-
vents lipid digestion and causes secondary mal-
absorption. One of the complications of the mal-
absorption syndrome is a bleeding tendency.
Vitamin K, a fat-soluble vitamin that is essential
to the blood-clotting mechanism, cannot be ab-
sorbed. Treatment for malabsorption syndrome
depends on its cause, and diet is carefully con-
trolled. Supplements are administered, such as
the fat-soluble vitamins A, D, E, and K.

Celiac Disease
Celiac disease is associated with gluten intoler-
ance and is characterized by poor nutrient ab-
sorption. Signs and symptoms include recur-
rent diarrhea, gas, abdominal cramps, and
systemic signs of malnutrition due to low caloric
intake and poor absorption of vitamins. Onset is
usually by age 1, when wheat products are first
consumed. Celiac disease seems to be genetic,
may involve immune dysfunction, affects twice
as many females as males, and is more common
among whites of European ancestry. Celiac dis-
ease affects about 2 million Americans, or 1 in
133 people. Celiac disease is diagnosed by the
signs and symptoms as well as by biopsy of the
small intestine, which reveals atrophy and flat-
tening of intestinal villi. Treatment involves
elimination of gluten from the diet, fluid re-
placement, and vitamin supplements.

Diverticulitis

Diverticula are little pouches or sacs formed
when the mucosal lining pushes through the
underlying muscle layer of the intestinal wall.
This condition is called diverticulosis and may

cause no harm in itself. Diverticulitis is an in-
flammation of the diverticula. Diverticulitis oc-
curs when the sacs become impacted with fecal
material and bacteria. The patient experiences
low, cramplike pain, usually on the left side of
the abdomen. As inflammation spreads, the
lumen of the intestine narrows, an obstruction
can develop, and abscesses frequently form. Di-
verticular disease is most prevalent in Western
industrialized nations where fiber consumption
is lowest. About 50% of older adults develop di-
verticulosis. Diverticular disease is diagnosed
with a barium enema. Antibiotic therapy, to-
gether with a controlled diet, is usually effective.
Figure 9–6 � shows an example of diverticulitis.

Regional Enteritis (Crohn’s Disease)
Regional enteritis is an inflammatory disease of
the intestine that most frequently affects the
upper colon and sometimes the distal end of the
ileum. Crohn’s disease is most prevalent in
adults ages 20 to 40, is two to three times more
common among Jewish populations, and is least
common in blacks. Possible causes include aller-
gies, immune disorders, or stress, but the exact
cause remains unknown. As inflammation pro-
gresses, the intestinal walls become thick and
rigid. With thickening, the lumen narrows and a
chronic obstruction develops. The pain of re-
gional enteritis resembles that of appendicitis,
occurring in the lower right quadrant of the ab-
domen, where a tender mass may be felt. Diar-
rhea alternating with constipation, and melena
(dark stools containing blood pigments) are com-
mon. Severe diarrhea can cause an electrolyte
imbalance because of the large amount of water
and salt lost in the stools. Anorexia, nausea, and
vomiting lead to weight loss. Periods of exacerba-

Prevention PLUS!
Bacteria, Coolers, and Food Poisoning
Refrigeration and freezing do not kill bacteria. The cold temperature inhibits their growth, which can resume at warmer
temperatures. Bacteria can multiply rapidly; under optimum conditions, they may double their numbers every 30 minutes.
A contaminated potato salad may be safe to eat right out of the refrigerator, but it may become the source of a serious
infection if brought to a picnic and left to stand at air temperature for a couple of hours. In other words, it is a good
idea to keep the potato salad in the cooler while you are playing softball at your next picnic!

Chapter Nine Diseases of the Gastrointestinal System ■ 2

Appendix
Cecum

Descending
colon

Sigmoid colon

Ascending
colon

Transverse colon

Diverticula

Diverticulitis

Figure 9–6 � Diverticulitis.

tion, remission, and relapse are common; during
flare-ups, the inflammation can also manifest as
rheumatoid arthritis. Severe cases entail a risk
for hemorrhage or perforation. Crohn’s disease is
diagnosed by elevated levels of white blood cells;
low levels of potassium, calcium, and magne-
sium; and by sigmoidoscopy or colonoscopy.
Biopsy confirms the diagnosis. Crohn’s disease
is usually treated with anti-inflammatory med-
ications such as corticosteroids and aminosal-
icylates, and with immunosuppressive agents
such as azathioprine, sulfasalazine, and ol-
salazine. Surgery is performed to correct compli-
cations such as obstruction, perforation, or mas-
sive hemorrhage. Ileostomy is necessary if the
large intestine has been severely damaged.

Chronic Ulcerative Colitis
Chronic ulcerative colitis is a serious inflamma-
tion of the colon characterized by extensive ul-
ceration of the colon and rectum. The incidence
of ulcerative colitis remains unknown but may
be as much as 100 per 100,000. Ulcerative coli-
tis occurs primarily in young adults, especially
women, and usually begins between ages

and 20. No known causes have been found;
however, ulcerative colitis may be related to au-
toimmunity, E. coli infection, stress, or hyper-
sensitivity to certain foods.

Typical symptoms include diarrhea with pus,
blood, and mucus in the stools, and cramplike

pain in the lower abdomen. Periods of remission
and exacerbation are common in ulcerative coli-
tis. Anemia often accompanies ulcerative colitis
because of the chronic blood loss through the
rectum. Increased risk for colon malignancy is
associated with long-standing ulcerative colitis.

Diagnosis is based on colonoscopy and a bar-
ium x-ray in which the colon has a characteris-
tic appearance; the normal pouchlike markings
of the colon are lacking, and the colon appears
straight and rigid, a “pipestem colon.”

Treatment is aimed at reducing symptoms,
replacing nutrients, stopping blood loss, and
preventing complications. The symptoms may
be alleviated by reducing stress, eliminating
foods found to trigger symptoms, and taking
adrenal corticosteroids such as prednisone and
hydrocortisone to control autoimmunity. If
these treatments are not effective, surgery may
be necessary, occasionally requiring a colos-
tomy. A colostomy is an artificial opening in the
abdominal wall with a segment of the large in-
testine attached. Fecal waste is evacuated
through this opening and collected in a bag. A
colostomy may be temporary or permanent de-
pending on the nature of the colon surgery.

Cancer of the Colon and Rectum
Cancer of the colon and rectum is a leading
cause of death from cancer in the United States
and is the fourth leading cause of cancer in the

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212 ■ Chapter Nine Diseases of the Gastrointestinal System

United States. The incidence in men and women
is roughly equal.

The symptoms vary according to the site of
the malignancy. A change in bowel habits, diar-
rhea, or constipation is symptomatic. As the
tumor grows, there may be abdominal discom-
fort and pressure. Blood often appears in the
stools, and continuous blood loss from the ma-
lignant tumor causes anemia. The mass can
partially or completely obstruct the lumen of the
colon. As the tumor invades underlying tissue,
the cancer cells spread through the lymph ves-
sels and veins. Colorectal cancer is diagnosed
with a digital rectal examination, sigmoid-
oscopy, colonoscopy, and biopsy.

Two diseases increase the risk for cancer of
the colon: long-standing ulcerative colitis and
familial polyposis of the colon. Familial polyposis
is a hereditary disease in which numerous
polyps develop in the intestinal tract. The
polyps usually give no symptoms unless a ma-
lignancy develops. Another factor associated
with risk for colon cancer is a diet high in red
meat and low in food sources of fiber, such as
vegetables, legumes, and whole-grain cereals.

Colorectal cancer grows slowly, tends to re-
main localized, and is thus potentially curable
with early diagnosis. As in all cancers, early de-
tection and treatment are essential to prevent its

spread. Most malignancies of the large intestine
are in the rectum or the sigmoid colon, which
makes their detection and removal easier than
malignant tumors in other areas of the digestive
tract. Chemotherapy is used when the tumor has
metastasized or if residual masses remain inop-
erable. (See Chapter 4.) If sections of the colon
are removed, a colostomy may be necessary.

Intestinal Obstructions
An obstruction can occur anywhere along the
intestinal tract, preventing contents within the
tract from moving forward. Obstructions are
classed as organic when there is some material
blockage, or as paralytic, in which case there is a
decrease in peristalsis, preventing the propul-
sion of intestinal contents.

Tumors and hernias, both hiatal and in-
guinal, can cause organic obstructions. The in-
testine may be twisted on itself, a condition
known as volvulus that may be unwound surgi-
cally (Figure 9–7 �). The intestine may be
kinked, allowing nothing to pass. Adhesions, the
linking of two surfaces normally separate, can
distort the tract. Abdominal adhesions some-
times follow surgery, when fibrous connective
tissue grows around the incision. Adhesions
also develop as a result of inflammation. An-

Twisted portion of
small intestine

Large intestine

Small
intestine

Figure 9–7 � Volvulus.

Chapter Nine Diseases of the Gastrointestinal System ■ 2

other type of organic obstruction is intussu-
sception, in which a segment of intestine tele-
scopes into the part forward to it. This occurs
more often in children than in adults. Figure
9–8 � shows various types of organic obstruc-
tions. An acute organic obstruction causes se-
vere pain. The abdomen is distended and vomit-
ing occurs. There is complete constipation; not
even gas, or flatus, is passed. Sometimes the ob-
struction can be relieved by means of a suction
tube, but frequently surgery is required. If the

obstruction is a strangulated hernia, a protru-
sion of intestine through the abdominal wall,
surgery is required because the blood supply is
cut off to the strangulated segment, and it can
become gangrenous.

A paralytic obstruction can result from peri-
tonitis. If a loop of small intestine is surrounded
by pus from the infection, the smooth muscle of
the intestinal wall cannot contract. Sphincters
can go into spasm and fail to open as a result of
intense pain.

Dilated stomach
and duodenum

Intestine dilated due
to obstruction

TUMOR

INTUSSUSCEPTION
(telescoping of small intestine)

Strangulated loop of intestine

Abdominal wall

INTESTINAL
OBSTRUCTIONS

VOLVULUS
(twisting of intestine)

DIAPHRAGMATIC HERNIA
(strangulation of intestine)

Volvulus

Figure 9–8 � Organic obstructions of the intestinal tract.

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214 ■ Chapter Nine Diseases of the Gastrointestinal System

Spastic Colon (Irritable Bowel Syndrome)
Irritable bowel syndrome or spastic colon is rela-
tively common, occurring in 20% of American
adults and affecting more women than men. Ir-
ritable bowel is marked by diarrhea, constipa-
tion, abdominal pain, and gas. The difference
between a spastic or irritable colon and the dis-
eases already discussed is that the spastic colon
has no lesion, no tumor, or ulceration. It is a
functional disorder of motility, the movement of
the colon. The pain is probably caused by mus-
cle spasms in the wall of the intestine.

Abuse of laxatives and consumption of certain
foods and beverages, particularly caffeine, alco-
hol, spicy foods, fatty foods, and concentrated
orange juice, can irritate the bowel. Foods such
as beans and cabbage, which contain carbohy-
drates fermented by colon bacteria, promote gas
production and should be avoided. Laxatives
should be avoided as well. Adding fiber to the
diet helps prevent constipation. Emotional
stress has an adverse effect on the digestive sys-
tem, because the nerves of the autonomic ner-
vous system affect digestion. If stressful situa-
tions can be alleviated, the colon will function
more normally. Tension-relieving activities,
sports, hobbies, or regular exercise may help.

Dysentery
The terms dysentery and diarrhea are often in-
correctly used interchangeably. Dysentery is an
infectious disease; diarrhea is a symptom.
Dysentery is an acute inflammation of the colon.
The major symptom of dysentery is diarrhea
containing pus, blood, and mucus accompanied

by severe abdominal pain. Bacteria, parasitic
worms, and other microorganisms can cause
dysentery. The protozoan Entamoeba histolytica,
which is transmitted in feces-contaminated food
and water, causes amebiasis, also called amoe-
bic dysentery. Amoebic dysentery is uncommon
in the United States and is usually found among
immigrants arriving from countries with poor
water quality and sanitary procedures. Ameri-
can travelers acquire amoebic dysentery when
drinking contaminated water abroad. E. histolyt-
ica invade the wall of the colon and cause nu-
merous ulcerations, which account for the pus
and blood in the stools. Bacillary dysentery is
caused by various species of gram-negative bac-
teria in the genus Shigella. Antibiotics can be ef-
fective for bacillary dysentery, and amebicides
are used for amoebic dysentery.

Diseases Indicated
by Stool Characteristics

Microscopic examination of stool may identify
the cause of food poisoning, gastroenteritis, or
dysentery. Other information can also be ob-
tained from stool samples. Signs of several of
the diseases discussed include blood in the
stools. Blood appears differently, however, de-
pending upon the site of bleeding.

If the blood in the stools is bright red, the
bleeding originated from the distal end of the
colon, the rectum. Streaks of red blood can indi-
cate bleeding hemorrhoids. This symptom can
also indicate cancer of the rectum. Dark blood

▼

Prevention PLUS!
Cancer Prevention through Detection
Early detection of colorectal cancer is the key to survival. Death rates are low for patients whose colorectal cancer is de-
tected at an early localized stage; about 9% die within 5 years. Death rates are much higher, however, when the diagno-
sis occurs at an advanced stage; about 92% die within 5 years. Screening remains underused even though its benefits
seem clear. Regular screening should be done for adults aged 50 years and over. This includes an annual fecal occult
blood test, a flexible sigmoidoscopy every 5 years, and a colonoscopy every 10 years. These tests can identify precancer-
ous polyps that can be removed, or they can detect cancer in the early localized stage, which can be treated before the
cancer has a chance to spread.

Chapter Nine Diseases of the Gastrointestinal System ■ 215

may appear in the stools, giving them a dark,
tarry appearance, the condition of melena. This
blood was altered as it passed through the diges-
tive tract, so it originated from the stomach or
duodenum. A bleeding ulcer or cancer of the
stomach may be indicated by melena. Certain
medications (those containing iron, for instance)
can also give this tarry appearance to the stools.
Blood may not be apparent to the naked eye, but
a chemical test can show its presence. This is re-
ferred to as occult blood. It can indicate bleeding
ulcers or a malignancy in the digestive tract.

If the stools are large and pale, appear greasy,
and float on water, they contain fat. This is a
symptom of malabsorption syndrome. It may also
indicate a diseased liver, gallbladder, or pancreas.
Diseases of these organs are discussed next.

Functions of the Liver
and the

Gallbladder

The liver is located below the diaphragm, in the
upper right quadrant of the abdominal region.
The liver is the largest glandular organ of the
body, and it is unique in that it has great pow-
ers of regeneration; it can replace damaged or
diseased cells. Still, chronic liver disease may
cause irreversible damage and loss of function.

The liver has a dual blood supply: It receives
oxygenated blood from the hepatic artery and
blood rich in nutrients from the portal vein. The
blood reaching the liver through the portal vein
comes from the stomach, intestines, spleen, and
pancreas. Blood from the small intestines car-
ries absorbed nutrients such as simple sugars
and amino acids. One of the functions of the
liver is to store any excess of these substances.
The liver plays an important role in maintaining
the proper level of glucose in the blood. It takes
up excess glucose, storing it as glycogen. When
the level of circulating glucose falls below nor-
mal, the liver converts glycogen into glucose,
which is then released into the blood. The liver
also stores iron and vitamins.

The liver synthesizes various proteins, includ-
ing enzymes necessary for cellular activities.
One means of evaluating liver function is to de-
termine the level of these enzymes in the blood.

▼

The liver also synthesizes plasma proteins. Al-
bumin is the plasma protein that has a water-
holding power within the blood vessels. If the al-
bumin level is too low, plasma seeps out of the
blood vessels and into the tissue spaces, caus-
ing edema. Other essential plasma proteins syn-
thesized by the liver are those required for blood
clotting: fibrinogen and prothrombin. If the liver
is seriously diseased or injured and cannot
make these proteins, hemorrhaging may occur.

The liver can detoxify various substances;
that is, it can make poisonous substances
harmless. Ammonia, which results from amino
acid metabolism, is converted to urea by the
liver. The urea then enters the bloodstream and
is excreted by the kidneys. Certain drugs and
chemicals are also detoxified by the liver. Spe-
cialized cells called Kupffer cells line the blood
spaces within the liver. These cells engulf and
digest bacteria and other foreign substances,
thus cleansing the blood.

Bile, necessary for fat digestion, is secreted by
the liver. Bile is an emulsifier, acting on fat in
such a way that the lipid enzymes can digest it.
The products of lipid digestion are then absorbed
by the walls of the small intestine. In the ab-
sence of bile, the fat-soluble vitamins A, D, E,
and K cannot be absorbed. Bile consists of water,
bile salts, cholesterol, and bilirubin, which is a
colored substance resulting from the breakdown
of hemoglobin. It is bilirubin that gives bile its
characteristic color of yellow or orange.

The gallbladder is a small, saclike structure
on the underside of the liver. Bile is secreted
continuously by the liver into the hepatic duct,
which carries bile to the gallbladder for storage
and concentration (Figure 9–9 �). The gallblad-
der releases the bile through the cystic duct to
the common hepatic duct, which carries the bile
to the duodenum. Release of bile is coordinated
with the appearance of fats in the duodenum.

Diseases of the

Liver

Liver disease manifests itself when chronic
damage to liver cells cannot be repaired. When
fibrous tissue replaces liver cells, the normal
functions of the liver become impaired.

216 ■ Chapter Nine Diseases of the Gastrointestinal System

Hepatic duct

Pancreas

Common bile
duct

Stomach

Cystic
duct

Mucous membrane
lining gallbladder

Right and left
hepatic ducts

Common
hepatic duct

Gallbladder
Liver

Duodenum

Figure 9–9 � Bile duct system of the liver and gallbladder.

Jaundice
One sign frequently associated with liver disease
is jaundice. Jaundice, or icterus, is a yellow or or-
ange discoloration of the skin, tissues, and the
whites of the eyes. It is caused by a build-up of
bilirubin, a pigment that is normally secreted in
the bile and removed from the body in the feces.

Jaundice has several causes. The normal flow
of bile from the gallbladder to the duodenum
may be obstructed by a tumor, a gallstone in the
duct system, or a congenital defect. Because the
bile cannot move forward, it leaks into the
blood, with bilirubin coloring the plasma. When
the blood reaches the kidneys, the bile appears
in the urine, giving it a dark color. Because bile
is unable to reach the duodenum, the stools are
light in color. They are usually described as clay
colored. Complications can result from this
blockage to bile flow. Infection or inflammation
of the gallbladder or bile ducts could occur.
Lack of bile interferes with fat digestion and ab-
sorption, which means that the fat-soluble vita-
mins are not being absorbed. In the absence of
vitamin K, bleeding tendencies may develop.
The obstruction can also cause liver damage.
Jaundice can also indicate liver disease, such
as hepatitis or cirrhosis.

Hemolytic jaundice has an entirely different
etiology. This type of jaundice accompanies the
hemolytic anemias explained in Chapter 7. In
these anemias, the red blood cells hemolyze,
and an excess of bilirubin results from the
breakdown of released hemoglobin. Abnormal
discoloration follows.

Viral Hepatitis
Hepatitis, or inflammation of the liver, is caused
by a number of factors, including several
viruses. Important causes are hepatitis virus A,
hepatitis virus B, hepatitis virus C, and hepati-
tis virus D. Hepatitis E is uncommon in the
United States.

Hepatitis virus A, formerly called infectious
hepatitis, is the least serious form and can de-
velop as an isolated case or in an epidemic. In
the United States, as many as 30,000 people
per year had hepatitis A infection until the vac-
cine was introduced, and since the 1990s this
number has dropped dramatically. Still, in large
crowded urban areas and in rural areas with
poor sanitation, the rate of infection can exceed
20 per 100,000. The incubation period, the time
from exposure to the development of symptoms,
is from 2 to 6 weeks. The symptoms include
anorexia, nausea, and mild fever. The urine be-
comes dark in color, and jaundice appears in
some cases. On examination, the liver may be
found to be enlarged and tender. Contaminated
water or food is the usual source of the infec-
tion, which spreads under conditions of poor
sanitation. The virus is excreted in the stools
and urine, infecting soil and water. Hepatitis
virus type A is usually mild in children; it is
sometimes more severe in adults. Prognosis is
usually good, with no permanent liver damage
resulting. Immunoglobulin injections provide
temporary protection against hepatitis virus
type A for people exposed to it. A vaccine now in
use has proven to be effective. Exposure to hep-
atitis A gives lifetime immunity.

Hepatitis virus B, formerly called serum he-
patitis, is a more serious and common disease,
affecting more than 60,000 Americans per year.
In fact, 1.25 million American are chronically
infected with hepatitis B, 25% of whom will die
from cirrhosis. The symptoms are similar to
those of hepatitis virus A but develop more
slowly. The incubation period is long, lasting
from 2 to 6 months. The severity of the disease
varies greatly. Those with poor nutritional sta-
tus, for example, will be more adversely affected
by hepatitis. Occasionally, a fulminating form of
hepatitis virus B develops, and it is fatal. This
form has a sudden onset and progresses

Chapter Nine Diseases of the Gastrointestinal System ■ 217

rapidly. Delirium is followed by a coma and
death. Hepatitis virus B can be transmitted by
donated blood or serum transfusions that con-
tain the virus. It also is transmitted sexually
and through contaminated needles or syringes
used by drug addicts. Physical condition at the
onset of the disease makes a difference in the
seriousness of the infection. Blood and plasma
are screened for hepatitis, but hospital person-
nel still must be well informed of the hazards
that can lead to acquiring hepatitis. Precautions
must be taken by nurses, laboratory techni-
cians, dialysis workers, and blood bank person-
nel to prevent becoming infected. Vaccination
provides immunity to the virus, and it should be
administered to personnel who handle or come
in close contact with blood or other bodily fluids
(see Chapter 3).

Hepatitis C infections have declined in the
United States to approximately 26,000 per year,
somewhat fewer than hepatitis B, but hepatitis
C remains the leading viral cause of chronic
liver disease and cirrhosis and is now the most
common reason for liver transplants. Because
of the very high rates of infection seen in the
1980s, over 4 million Americans are infected
today, 3.2 million of whom are chronically in-
fected. The initial symptoms are nonspecific and
similar to those of hepatitis A or B, but the dis-
ease persists for months, even years. About
20% of those infected develop cirrhosis, and a
number of these cases can lead to end-stage
liver disease. The virus is transmitted mostly
through blood transfusions, although transmis-
sion has been traced to intravenous drug use,
and epidemiologic studies show a risk associ-
ated with sexual contact with someone with he-
patitis and with having had more than one sex
partner in a year. Treatments of hepatitis C in-
clude interferon injections and oral ribavirin.
Treatment for end-stage cirrhosis may include
liver transplant.

Hepatitis D virus is described as a defective
virus because it cannot reproduce in a cell un-
less the cell is also infected with hepatitis B. The
resulting disease is more serious and more fre-
quently progresses to chronic liver disease.
Rates of hepatitis D are not known because sur-
veillance is not systematically conducted; how-
ever, hepatitis D is quite uncommon but its

transmission is known to be similar to that of
hepatitis B.

Hepatitis E is very rare in the United States,
but worldwide it is the leading cause of epi-
demics of infectious hepatitis. Major epidemics
occur in Africa, Asia, and Mexico, where it is
transmitted primarily through fecal-contami-
nated drinking water. Nearly every case in the
United States occurs in travelers to areas where
the disease is endemic. No effective treatment or
vaccine exists. Fortunately, there is no evidence
that type E progresses to chronic disease.

Cirrhosis of the Liver
Cirrhosis is chronic destruction of liver cells and
tissues with a nodular, bumpy regeneration.
Cirrhosis is the twelfth leading cause if death in
the United States, killing about 26,000 people
each year. Alcoholic cirrhosis, the most common
type of cirrhosis, is described in detail. This dis-
ease is also called portal, Laennec, or fatty nu-
tritional cirrhosis (an accumulation of fat often
develops within the liver). The exact effect of ex-
cessive alcohol on the liver is not known, but it
may be related to the malnutrition that fre-
quently accompanies chronic alcoholism, or the
alcohol itself may be toxic. In the normal liver,
there is a highly organized arrangement of cells,
blood vessels, and bile ducts. A cirrhotic liver
loses this organization and, as a result, the liver
cannot function. Liver cells die and are replaced
by fibrous connective tissue and scar tissue.
This tissue has none of the liver cell functions.
At first, the liver is generally enlarged due to re-
generation but then becomes smaller as the fi-
brous connective tissue contracts. The surface
acquires a nodular appearance. This is some-
times called a “hobnailed” liver.

In cirrhosis, circulation through the liver is
impaired. As a result, high pressure builds in
vessels of the abdomen and in other areas. The
esophageal veins swell, forming esophageal
varices. Abdominal organs like the spleen, pan-
creas, and stomach also swell. These organs
and vessels may hemorrhage, causing hemor-
rhagic shock. Hemorrhage of vessels in the
stomach or intestines may cause vomiting of
blood, hematemesis. A characteristic symptom of
cirrhosis is distention of the abdomen caused by

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218 ■ Chapter Nine Diseases of the Gastrointestinal System

the accumulation of fluid in the peritoneal cav-
ity. This fluid is called ascites and develops as a
result of liver failure. The pressure within the
obstructed veins forces plasma into the abdom-
inal cavity. This fluid often has to be drained.
When the liver fails to produce adequate
amounts of albumin, an albumin deficiency,
hypoalbuminemia, develops and fluid leaks out of
the blood vessels, causing edema. Because the
necrotic cells of the cirrhotic patient fail to pro-
duce albumin, ascitic fluid develops, as does
edema, particularly in the ankles and legs.

Blockage of the bile ducts, like that of the
blood vessels, follows the disorganization of the
liver. Bile accumulates in the blood, leading to

jaundice and, because bile is not secreted into
the duodenum, stools are clay colored. The ex-
cess of bile, carried by the blood to the kidneys,
imparts a dark color to urine.

Other signs are related to the fact that the
diseased liver cannot perform its usual bio-
chemical activities. Normally, the liver inacti-
vates small amounts of female sex hormones se-
creted by the adrenal glands in both males and
females. Estrogens then have no effect on the
male, but the cirrhotic liver does not inactivate
estrogens. They accumulate and have a feminiz-
ing effect on males. The breasts enlarge, a con-
dition known as gynecomastia, and the palms of
the hands become red because of the estrogen

▲ Normal human liver.

SIDE by SIDE ■ Cirrhosis

Prevention PLUS!
Know Your Viruses
The more you know about how a virus is transmitted, the better prepared you can be to prevent infection. Hepatitis A is
transmitted primarily through contaminated food and water. Workers in the food-service industry must use sanitary pro-
cedures when handling food, including the simple task of washing their hands. You can protect yourself at home by
thoroughly cooking meat and seafood. Hepatitis B and C are transmitted through blood transfusions, contaminated nee-
dles and syringes, and sexual intercourse. Healthcare workers receive vaccination against hepatitis B, and blood is
screened for contamination by hepatitis B and C.

▲ Cirrhosis of the liver from chronic alcoholism.

Chapter Nine Diseases of the Gastrointestinal System ■ 219

level. Hair on the chest is lost, and a female-type
distribution of hair develops. Atrophy of the tes-
ticles can also occur.

The damaged liver cells are unable to carry
out their normal function of detoxification, so
ammonia and other poisonous substances ac-
cumulate in the blood and affect the brain,
causing various neurologic disorders. Confu-
sion and disorientation, even to the point of stu-
por, and a characteristic tremor or shaking
develop. This shaking is called “liver flap.” Som-
nolence or abnormal sleepiness are symptoms
of cirrhosis. Hepatic coma is a possible cause of
death in cirrhosis.

Although chronic alcoholism is the leading
cause of cirrhosis, other diseases can also cause
cirrhosis. Severe chronic hepatitis, chronic in-
flammation of the bile ducts, and certain drugs
and toxins can cause necrosis of the liver cells,
which is the first step in the development of
cirrhosis.

There is no effective treatment for cirrhosis.
Liver damage can not be reversed, but further
damage can be prevented by treating alcoholism
or liver infections that are at the root of cirrho-
sis. Symptoms of cirrhosis may be treated. For
example, edema is treated with diuretics and
portal hypertension is remedied with beta
blockers to reduce blood pressure. Liver trans-
plant is the only way to restore liver function.

Cancer of the Liver
Hepatocarcinoma, or cancer of the liver, is a pri-
mary malignancy of the liver that is rare but
has a high mortality rate. While liver cancer
comprises 1% of all cancers in the United
States, it accounts for 6% and 2% of cancer
deaths in men and women, respectively. Liver
cancer is most prevalent in men over age 60,
and the incidence increases with age. In Africa
and parts of Asia, where there is a high inci-
dence of hepatitis B infection, liver cancer com-
prises 10% to 50% of all cancers. Most cancer
found in the liver is secondary, which means it
results from metastasis from cancer in other or-
gans, especially the colon, rectum, stomach,
pancreas, esophagus, lung, or breast. Primary
cancer of the liver is caused chiefly by viral hep-

atitis and cirrhosis. Other causes of liver cancer
may include aflatoxin, a toxin from a mold that
grows on peanuts and rice.

The symptoms of hepatocarcinoma vary ac-
cording to the site of the tumor. If the tumor ob-
structs the portal vein, ascites develops in the
abdominal cavity, as it does in cirrhosis. If the
fluid contains blood, a malignancy is indicated.
A tumor blocking the bile duct will cause jaun-
dice. General symptoms may include loss of
weight and an abdominal mass and pain in the
upper right quadrant of the abdomen.

Diagnosis includes serum levels of enzymes
that arise from diseased liver tissue, but correct
diagnosis depends on needle biopsy or open
biopsy. Prognosis for cancer of the liver is poor
because usually the malignancy has developed
elsewhere and has spread to the liver.

Diseases of the Gallbladder

The gallbladder stores and concentrates bile.
Gallbladder disease impairs the storage and de-
livery of bile to the duodenum.

Gallstones (Cholelithiasis)
Gallstones are precipitated bile components in
the gallbladder and bile ducts. Gallstones and
gallbladder disorders (cholecystitis, discussed
in the following subsection) are common, affect-
ing about 1 million Americans per year. Gall-
stones affect twice as many women as men. The
stones arise in the gallbladder when the bile
composition changes or when gallbladder mus-
cle activity reduces, as it may during preg-
nancy, use of oral contraceptives, diabetes mel-
litus, obesity, cirrhosis, and pancreatitis. The
stones consist principally of cholesterol, biliru-
bin, and calcium when in excess. Gallstones,
also called biliary calculi, may be present in the
gallbladder and give no symptoms. There may
be one gallstone present or several hundred,
which can be large or small (Figure 9–10 �).
Small stones, referred to as gravel, can enter
the common bile duct and cause an obstruction
with excruciating pain.

220 ■ Chapter Nine Diseases of the Gastrointestinal System

Figure 9–10 � Gallbladder opening showing gallstones. (Martin Rotker/Phototake NYC)

Gallstones can be diagnosed and located by
ultrasound and x-ray. The usual treatment for
gallstones is surgical removal of the gallbladder,
a cholecystectomy. The cystic duct is ligated and
the common bile duct examined for stones. Oc-
casionally, undetected cholesterol stones are re-
tained in the common bile duct after surgery.
Administering a solubilizing agent through a
catheter into the bile duct may dissolve the re-
maining stones, preventing the necessity of re-
peated surgery.

Cholecystitis
Cholecystitis is an inflammation of the gallblad-
der usually associated with gallstones
(cholelithiasis). Acute cholecystitis is most com-
mon in middle age. The gallbladder becomes ex-
tremely swollen, causing pain under the right
rib cage that radiates to the right shoulder. At
this point, the gallbladder can usually be pal-
pated. Chills and fever, nausea and vomiting,
belching and indigestion are symptoms; in
chronic cholecystitis these symptoms occur es-
pecially after eating fatty foods. The presence of
fat in the duodenum stimulates the gallbladder
to contract and release bile, and the contraction
of the inflamed gallbladder causes pain. Pro-
longed inflammation causes the gallbladder to
lose its ability to concentrate bile. The walls of
the gallbladder may thicken, making it impossi-
ble for the gallbladder to contract properly. Seri-
ous complications can result from cholecystitis.

Lack of blood flow because of the obstruction
brought about by the swelling can cause an in-
farction. With the death of the tissues, gangrene
can set in. The acutely inflamed gallbladder, like
an inflamed appendix, may rupture, causing
peritonitis. A complication of chronic cholecysti-
tis is that bile accumulates in the bile ducts of
the liver. This causes necrosis and fibrosis of
the liver cells lining the ducts. This is another
form of cirrhosis, biliary (bile) cirrhosis.

Structure and Function
of the Pancreas

The pancreas is a fish-shaped organ extending
across the abdomen behind the stomach. The
head fits into the curve of the duodenum, where
the pancreatic duct empties digestive enzymes
from the pancreas. These enzymes include amy-
lase, which breaks down carbohydrates; trypsin
and chymotrypsin, which digest protein; and li-
pase, which breaks down lipid or fat.

Diseases of the pancreas severely interfere
with digestion and absorption of nutrients.
Also, a diseased pancreas may release enzymes
that can damage the pancreas and surround-
ing tissues. Figure 9–11 � shows the structure
of the pancreas. Figure 9–12 � shows the rela-
tionship between the pancreas and other diges-
tive organs.

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Chapter Nine Diseases of the Gastrointestinal System ■ 221

Common bile duct

Accessory
duct

Ampula
of vater

Pancreatic duct

Cells that
secrete
digestive
juices

EXOCRINE PORTION

ENDOCRINE PORTION

Duct

Islands of
Langerhans

Insulin-
secreting
cell

Glucagon-
secreting
cell

Figure 9–11 � The pancreas: An endocrine and exocrine gland.

Diseases of the Pancreas

Pancreatitis
Acute pancreatitis is a serious, painful inflam-
mation of the pancreas. Pancreatitis is more
prevalent in women than in men and usually

▼

occurs after age 40. In men it is often associated
with alcoholism or peptic ulcers. In women it is
more commonly associated with gallbladder dis-
ease. The prognosis is good if pancreatitis is as-
sociated with gallbladder disease but is very
poor if it is related to alcoholism. Pancreatitis

Pancreatic duct
Common bile duct

Common hepatic ductCystic duct

Right and left hepatic ducts

Gallbladder
(cut view)

Accessory duct

Duodenum
(cut view)

Ampulla of vater

Figure 9–12 � Relationship between the
pancreas and the digestive system.

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222 ■ Chapter Nine Diseases of the Gastrointestinal System

Pancreas

Cancer

Figure 9–13 � Pancreatic cancer. A common site of pancreatic
cancer is in the head of the pancreas within the pancreatic ducts.

may be caused by local swelling, necrosis, hem-
orrhage, or trauma.

Severe, steady abdominal pain of sudden
onset is the first symptom. The intense pain ra-
diates to the back and resembles the sharp pain
of a perforated ulcer. Drawing up the knees or
assuming a sitting position may provide some
relief. There may also be nausea and vomiting.
Jaundice sometimes develops if the swelling
blocks the common bile duct. If a large area of
the pancreas is affected, both endocrine and di-
gestive functions of the gland become impaired.
In the absence of lipid enzymes from the pan-
creas, fat cannot be digested, resulting in greasy
stools with a foul odor. Secondary malabsorp-
tion syndrome develops because fat that is not
digested cannot be absorbed. In pancreatitis,
the protein- and lipid-digesting enzymes be-
come activated within the pancreas and begin to
digest the organ itself. Severe necrosis and
edema of the pancreas result. The digestion can
extend into blood vessels, which causes severe
internal bleeding and shock. When the condi-
tion becomes this severe, it is called acute hem-
orrhagic pancreatitis.

The most significant diagnostic procedures
for pancreatitis are blood and urine tests for
amylase. Treatment is aimed at maintaining cir-
culation to the pancreas and surrounding tis-
sues, maintaining blood and fluid volume, and
reducing pain.

Cancer of the Pancreas
Cancer of the pancreas, adenocarcinoma, has a
high mortality rate. It occurs more frequently in
males than in females, is most prevalent in men
between age 35 and 70, and exhibits the highest
prevalence in Israel, the United States, Sweden,
and Canada. Pancreatic cancer is linked to ciga-
rette smoking, high-protein and -fat diets, food
additives, and exposure to industrial chemicals
like beta-naphthalene, benzidine, and urea.
Chronic alcohol abuse, chronic pancreatitis,
and diabetes mellitus increase the risk of devel-
oping pancreatic cancer.

A malignancy in the head of the pancreas
can block the common bile duct (Figure 9–13 �),
and symptoms are experienced earlier than
those of cancer in the body or tail of the pan-

creas, which can be very advanced before it is
discovered. Obstruction of the bile duct causes
jaundice and impairs digestion because the
pancreatic enzymes and bile cannot enter the
duodenum. This causes malabsorption of fat
and clay-colored stools; sufficient nutrients
and calories cannot be absorbed, and weight
loss occurs. Great pain is experienced as the
tumor grows, and the cancer usually metasta-
sizes to the surrounding organs: the duode-
num, stomach, and liver.

Diagnosis depends on laparoscopic biopsy
and ultrasound. Prognosis for cancer of the
pancreas is poor, and death occurs in a rela-
tively short time. Treatment, which is rarely
successful, includes surgery, chemotherapy,
and radiation.

Age-Related Diseases

Infants and young children are especially vul-
nerable to the effects of digestive system disor-
ders and diseases because their growing and
developing bodies require substantial fluids,

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Chapter Nine Diseases of the Gastrointestinal System ■ 223

calories, and nutrients. For example, unchecked
vomiting and diarrhea can cause dehydration
and malnutrition more easily in children than in
adults. The digestive system functions fairly
well in healthy elderly people, despite normal
age-related changes like thinning mucosa and
decreased muscle motility. However, some dis-
eases occur with greater frequency with in-
creasing age and thus significantly impact el-
derly populations.

Mouth and Esophagus
Dental caries (cavities) are more prevalent in
children than in adults. After adolescence, the
incidence of caries reduces and the risk for gin-
givitis and periodontal disease increases. Peri-
odontal disease and osteoporosis contribute to
tooth loss in elderly people. The number of
taste buds decrease, and together with de-
creased saliva secretion, this may lead to de-
creased appetite. Esophageal cancer incidence
is highest in those over age 60. As stated ear-
lier, this cancer is closely linked with the use of
alcohol and tobacco.

Gastrointestinal Tract
Infectious diarrheal diseases are the leading
cause of death in children worldwide. Children
cannot tolerate the loss of enormous amounts of
water, electrolytes, and nutrients associated
with diarrhea. Hiatal hernia is a common disor-
der in elderly people. Peptic ulcers are no more
common in elderly than in middle-age people;
however, the risk of hemorrhage is greater in old
age. Colon cancer incidence increases after age
45, which emphasizes the importance of regular
screening and early diagnosis. Diverticula are
most common in elderly, and therefore the inci-
dence of diverticulitis rises. Diarrhea poses a
great risk of dehydration and malnutrition.

Therefore, gastrointestinal infections like food
poisoning and dysentery can be serious dis-
eases. Overall, the function of the intestines re-
mains fairly normal, although intestinal motility
is slightly decreased. Thus, changes in diet or
new medications that affect intestinal motility
can more easily lead to constipation or diarrhea.

Liver and Gallbladder
Disorders are uncommon in children. In adult-
hood, liver function diminishes with increasing
age, which results in the persistence of high
blood levels of medications or toxins. In old age,
levels of clotting factors decline, increasing the
risk for hemorrhage. The incidence of cholelithi-
asis is highest in those over age 80.

Pancreas
Disorders in children are uncommon, although
insulin-dependent diabetes does have its onset
in childhood. (See Chapter 12.) The incidence of
pancreatic cancer peaks in the sixties and is
most common among older men. Acute pancre-
atitis is common in the elderly. In younger peo-
ple, acute pancreatitis is associated with alco-
holism, while in the elderly acute pancreatitis is
more likely due to gallstones that block the pan-
creatic duct.

R E S O U R C E S

American Cancer Society: www.cancer.org

American Gastroenterological Association: www.gastro.org

American Liver Society: www.liversociety.org

National Institute of Health, National Digestive Diseases
Information Clearinghouse: digestive.niddk.nih.gov

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224 ■ Chapter Nine Diseases of the Gastrointestinal System

DISEASES AT A GLANCE
Digestive System

DISEASE ETIOLOGY SIGNS AND SYMPTOMS

Stomatitis Bacteria, viruses, fungi Redness, ulcers, patches, bleeding, depending on
the cause

Cancer of the mouth Use of tobacco products, especially in
conjunction with consuming alcohol

Abnormal growths, sores, or lesions that don’t heal

Cancer of the esophagus Use of tobacco and alcohol Dysphagia, vomiting, weight loss

Esophagitis Acid reflux due to incompetent cardiac
sphincter

Burning chest pain (heartburn), especially after
eating or while lying down

Esophageal varices Increased venous pressure; accompanies
advanced cirrhosis

Dilated esophageal veins, hemorrhage

Hiatal hernia Stomach protrudes through weakened
diaphragm

Indigestion, heartburn following meals, acid reflux,
and esophagitis

Gastritis Aspirin, coffee, tobacco, alcohol, infection Stomach pain, hematemesis

Chronic atrophic gastritis Degeneration of stomach mucosa results in no
HCl secretion and no intrinsic factor secretion

Gastritis, poor digestion and absorption of
nutrients, weight loss

Peptic ulcer Infection with H. pylori and erosion of mucosa
by stomach acid

Upper abdominal pain, hemorrhage, blood in stool

Gastroenteritis Food- and water-borne infection by bacteria,
viruses, protozoa

Nausea, vomiting, diarrhea, abdominal discomfort
or pain, and possibly fever, depending on the
pathogen

Chapter Nine Diseases of the Gastrointestinal System ■ 225

DIAGNOSIS TREATMENT PREVENTION LIFESPAN

Physical exam,
immunodiagnostic tests,
and pathogen culture

Antibiotics, antivirals, or
antifungals, depending on the
pathogen

Good oral hygiene; do not
use antibiotics unnecessarily
or incorrectly

More common in infants, young
children, and older adults with
weakened immune systems

Physical exam, biopsy Surgical excision of tumor,
radiation

Avoid tobacco products; use
alcohol only in moderation

Occurs in adults; incidence
increases with age

Endoscopy and esophageal
washings

Surgery, radiation,
chemotherapy

Avoid tobacco products; use
alcohol only in moderation
Occurs in adults; incidence
increases with age

Physical exam Nonirritating diet, antacids,
acid-reducing medications

Take small meals; avoid
known irritants

Occurs in adults; incidence
increases with age

Endoscopy, physical exam,
history of alcoholism

Hemorrhage requires infusion of
vasopressin or insertion of
inflatable tube to compress veins;
surgical bypass of portal veins to
reduce intravenous pressure

Treat underlying alcoholism
or liver disease

Occurs in adults; incidence
increases with age

X-ray Avoid irritating foods, eat
frequent small meals, surgery to
repair diaphragm

Avoid spicy food, caffeine;
eat small meals

Occurs in adults; incidence
increases with age

Gastroscopy Avoid irritants, drink ice water,
take antacid medications;
surgery to control bleeding

Avoid known irritants Occurs in adults; incidence
increases with age

Analysis of stomach content
reveals low levels of HCl and
intrinsic factor

Avoid stomach irritants, take
vitamin B12 supplements

Avoid known irritants Occurs in adults; incidence
increases with age

Gastroscopy, gastric
washings, barium x-ray

Antibiotics Reduce stress Occurs in adults; incidence
increases with age

Stool culture, history Fluid and electrolyte
replacement; antidiarrheal
medication; self-limiting in
healthy people

Safe food handling,
including correct storage,
refrigeration, and thorough
cooking as needed

Occurs at all ages; especially
debilitating in young children
and older adults

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DISEASES AT A GLANCE
Digestive System (continued)

DISEASE ETIOLOGY SIGNS AND SYMPTOMS

Cancer of the stomach Idiopathic; associated with salted, cured foods
and diet low in vegetables and fruit; associated
with prior infections with H. pylori

Appetite loss, stomach discomfort, hematemesis,
blood in stool, late-stage pain

Appendicitis Obstruction with fecal material leads to
infection, inflammation, and necrosis

Acute lower right quadrant abdominal pain,
nausea, fever

Malabsorption syndrome Congenitally abnormal intestinal mucosa or
malabsorption secondary to diseases of
pancreas or gallbladder

Malnutrition, failure to absorb fats and fat-soluble
vitamins, failure to grow in children and weight
loss in adults

Diverticulitis Diverticula of colon become impacted with
fecal material and infected or inflamed

Cramping and pain in lower abdomen

Regional enteritis (Crohn’s
disease)

Idiopathic; possible link to autoimmune
disease

Lower right pain, diarrhea and constipation,
emission and exacerbation, weight loss, melena

Chronic ulcerative colitis Idiopathic; may be autoimmune, stress related,
food allergy related

Diarrhea; pus, blood, mucus in stool; cramping in
lower abdomen

Cancer of colon and rectum Genetic; associated with familial polyposis and
chronic ulcerative colitis

Change in bowel habits, diarrhea or constipation,
blood in stool

Spastic colon/irritable bowel
syndrome

Abuse of laxatives; irritating foods; stress Diarrhea, pain, gas, constipation

Dysentery Food- or water-borne intestinal infection by
bacteria or protozoa

Abdominal pain, bloody diarrhea with pus and
mucus

Viral hepatitis A (infectious
hepatitis)

Food- or water-borne infection with hepatitis A
virus

Anorexia, nausea, mild fever, jaundice, enlarged
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Chapter Nine Diseases of the Gastrointestinal System ■ 227

DIAGNOSIS TREATMENT PREVENTION LIFESPAN

Gastroscopy, biopsy, gastric
fluid analysis (low HCl),
barium x-ray

Surgery, chemotherapy Reduce intake of salt and
cured meat

Occurs in adults; incidence
increases with age

Blood count, physical exam Surgery Maintain good bowel
habits

Most prevalent puberty through
20s

Stool analysis and history Manage diet and take vitamin
supplements

Treat underlying diseases Onset around age 1 as gluten
introduced in solid meals

Endoscopy Antibiotics, manage diet Good bowel habits Occurs in young adults; incidence
increases with age

Stool analysis, endoscopy,
patchy thickening of
intestinal wall

Corticosteroids, occasionally
surgery

None Occurs in young adults; incidence
increases with age

Stool analysis, endoscopy,
diffuse thickening of colon
(pipestem colon)

Corticosteroids, stress reduction,
diet management, colostomy

Reduce stress Occurs in young adults; incidence
increases with age

Endoscopy, biopsy, barium
x-ray, stool analysis

Surgery, radiation,
chemotherapy

Regular screening to
include endoscopy and
biopsy if at risk

Occurs in adults; incidence
increases with age

History and physical exam;
no lesions present

Avoid caffeine, alcohol, spicy
food, fat; increase fiber in diet;
reduce stress

Avoid laxatives Occurs in young adults; incidence
increases with age

Stool culture and history Antibiotics if bacterial and
amebicides if caused by
protozoa

Safe food and water
handling

Occurs at all ages; especially
debilitating for young children
and older adults

Physical exam, stool analysis,
immunodiagnostics

Immunoglobulin injections for
exposures and infections

Vaccine; safe food and
water handling

Occurs at all ages; especially
debilitating for young children
and older adults
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DISEASES AT A GLANCE
Digestive System (continued)
DISEASE ETIOLOGY SIGNS AND SYMPTOMS

Hepatitis B (serum hepatitis) Blood-borne or sexually transmitted infection
with hepatitis B virus

2–6-month incubation period followed by anorexia,
nausea, mild fever, jaundice, enlarged tender liver;
may lead to chronic hepatitis and cirrhosis

Hepatitis C Blood-borne or sexually transmitted infection
with hepatitis C virus

Symptoms as for hepatitis A and hepatitis B
following incubation period of months to decades;
commonly results in cirrhosis and end-stage liver
disease

Hepatitis D Rare blood-borne or sexually transmitted co-
infection with hepatitis D virus and hepatitis B
virus

Same as for hepatitis B; more serious and
frequently progresses to chronic liver diseases

Hepatitis E Water-borne infection with hepatitis E virus
rare in United States

As for hepatitis A

Cirrhosis Alcohol-induced damage to liver; hepatitis Jaundice, abdominal distension, ascites, bleeding
tendencies, edema, malabsorption of fats,
gynecosmastia, delerium tremens, hepatic coma

Cancer of the liver Primary carcinoma is complication of cirrhosis;
more common is secondary or metastatic

Bile duct obstruction, jaundice, impaired clotting,
ascites, weight loss

Cholecystitis Obstruction by infection/inflammation or by
tumor

Upper right abdominal pain especially following a
meal of fatty food; nausea, indigestion, belching

Cholelithiasis Related to obesity; higher incidence in
pregnancy and among women

None, or upper right abdominal pain especially
following a meal

Pancreatitis Idiopathic, commonly associated with excessive
alcohol consumption or with gallstones

Acute, severe, sharp, radiating abdominal pain; risk
of hemorrhage; jaundice; vomiting; malabsorption

Cancer of the pancreas Linked to cigarette smoking, alcohol abuse,
chemical carcinogens, chronic pancreatitis,
diabetes mellitus

Malabsorption, jaundice, upper abdominal pain

228

DIAGNOSIS TREATMENT PREVENTION LIFESPAN
Physical exam, stool analysis,
immunodiagnostics

Immunoglobulin injections for
exposures and infections,
antiviral medications, vaccine
for prevention

Vaccine Occurs at all ages; especially
debilitating for young children
and older adults

Physical exam, stool analysis,
immunodiagnostics

Ribavarin, interferon, liver
transplant

Safe sex, avoid injection
drug abuse

Occurs at all ages; especially
debilitating for young children
and older adults
Physical exam, stool analysis,
immunodiagnostics

Immunoglobulin injections,
antiviral

Safe sex, avoid injection
drug abuse
Occurs at all ages; especially
debilitating for young children
and older adults
Physical exam, stool analysis,
immunodiagnostics

No treatment, no vaccine Safe food and water
handling

Occurs at all ages; especially
debilitating for young children
and older adults

Patient history, physical
exam, serum liver enzyme
levels

No specific treatment;
symptomatic treatment for
edema and portal hypertension
or bleeding; improved diet, liver
transplant

Treat underlying alcoholism
or liver disease

Occurs in adults

Ultrasound, CT scan, needle
biopsy

Chemotherapy (prognosis poor) None Rare; occurs in adults and
occasionally children

Ultrasound, CT scan, fecal
fat test

Cholecystectomy None

Occurs in young adults and
prevalence increases with age

Ultrasound, CT scan, fecal
fat test

Cholecystectomy, administration
of solubilizing agent into bile
duct

Reduce weight Occurs in young adults and
prevalence increases with age

Ultrasound, CT scan, serum
pancreatic enzymes

No specific treatment; analgesics,
fluid replacement, IV nutrients

Treat underlying
alcoholism

Occurs in young adults and
prevalence increases with age
Ultrasound, CT scan, needle
biopsy

Chemotherapy (prognosis poor) Stop tobacco use, alcohol
abuse, treat underlying
diabetes

Occurs in young adults and
prevalence increases with age

229

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Human Diseases: A Systemic Approach, Seventh Edition, by Mark Zelman, Ph.D., Elaine Tompary, PharmD, Jill Raymond, Ph.D., Paul Holdaway, MA,
and Mary Lou Mulvihill, Ph.D. Published by Prentice Hall. Copyright © 2010 by Pearson Education, Inc.

6. Which statement about cirrhosis is FALSE?

a. Irreversible degenerative changes occur in the liver.
b. The normal liver tissue is replaced with fibrous scar tissue.
c. It is most often caused by diabetes.
d. It is associated with esophageal varices.

7. Acute pancreatitis is most closely associated with
____________________.

a. hepatitis C virus infection
b. chronic alcoholism
c. bile duct obstruction
d. complication of cirrhosis

8. Esophageal varices arise in which disease?

a. cirrhosis b. pancreatic cancer
c. cholecystitis d. cholelithiasis

9. Oral thrush is caused by ____________________.

a. Candida albicans
b. herpes simplex virus type 1
c. Treponema pallidum
d. Streptococcus pyogenes virus type 1

10. Pain in the upper right quadrant, especially after eating,
could be a sign of ____________________.

a. appendicitis b. pancreatitis
c. cholecystitis d. colitis

1. Which of the following is a sign of gastritis?

a. constipation
b. inflammation of stomach mucosa
c. achlorhydria
d. diarrhea

2. Recurrent bloody diarrhea may be a symptom of
____________________.

a. gastric ulcer b. ulcerative colitis
c. hiatal hernia d. esophagitis

3. Which disease is characterized by the destruction of intestinal
villi, leading to inability to absorb fats and other nutrients?

a. ulcerative colitis
b. celiac disease/malabsorption syndrome
c. Crohn’s disease
d. peptic ulcer

4. Small pouches of the large intestine become inflamed dur-
ing which disease?

a. Crohn’s disease b. gastritis
c. hemorrhoids d. diverticulitis

5. Which statement about pancreatic cancer is FALSE?

a. It is characterized by abdominal pain, weakness,
weight loss.

b. It has a higher incidence with age.
c. Most cancers are diagnosed after the cancer has

metastasized.
d. The prognosis is good with an 85% cure rate.

2. T. W. experiences sharp pain in his upper right abdomen
after eating a high-fat meal. Also, he has noted that his
feces are grayish white instead of brown. What disease is
the likely cause of his symptoms? Explain why each of these
symptoms occurs with this disease.

3. Explain how cirrhosis leads to each of these signs and symp-
toms: jaundice, malnutrition, hemorrhage, esophageal varices.

1. A 45-year-old woman experiences frequent heartburn, dif-
ficulty swallowing, and sharp pains below her sternum. At
night, she experiences gastric reflux, or a regurgitation of
stomach acid into the esophagus, a condition that is ex-
tremely painful. What could produce these symptoms?
What diagnostic procedures could be used? How should she
be treated?

230 ■ Chapter Nine Diseases of the Gastrointestinal System

Interactive Exercises

Cases for Critical Thinking

Multiple Choice

Chapter Nine Diseases of the Gastrointestinal System ■ 231

True or False

_______ 1. Hemorrhoids are caused by infection with E. coli.

_______ 2. Oral and esophageal cancers are linked to tobacco and alcohol use.

_______ 3. Drinking too much water causes diarrhea.

_______ 4. Dark stools are known as melena.

_______ 5. Neurologic disorders can accompany liver disease.

_______ 6. Hepatitis A is acquired through blood products.

_______ 7. Most cancer in the liver is primary liver cancer.

_______ 8. Gallstones are made of undigested food particles too large to pass.

_______ 9. There is no vaccine for hepatitis B.

_______ 10. Gastric ulcers are caused by infection with Helicobacter pylori.

Fill-Ins

1. Entamoeba histolytica is the cause of ____________________ ____________________.

2. Thickened intestinal walls, leading to obstruction and abdominal pain, are found in
____________________ ____________________.

3. An abdominal ____________________ is protrusion of an organ through abdominal wall muscles.

4. An instrument called a(n) ____________________ is used to view the lining of the esophagus
or other organs of the digestive tract.

5. Hepatitis type ____________________ is the major viral cause of cirrhosis.

6. Cholecystectomy is used to treat ____________________.

7. Biliary cirrhosis arises if there is obstruction of the ____________________
____________________.

8. Accumulation of fluid in the abdomen is called ____________________.

9. Stomatitis refers to inflammation of the ____________________.

10. The primary function of the ____________________ ____________________ is to absorb water.

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and Mary Lou Mulvihill, Ph.D. Published by Prentice Hall. Copyright © 2010 by Pearson Education, Inc.

232 ■ Chapter Nine Diseases of the Gastrointestinal System

Labeling Exercise

Use the blank lines on the right to label the following images.

5
3
4
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7
8
9

11
15

1
2
3
4
5
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and Mary Lou Mulvihill, Ph.D. Published by Prentice Hall. Copyright © 2010 by Pearson Education, Inc.

Multimedia Preview

Additional interactive resources and activities for this chapter can be found on the Companion Web-
site. For videos, audio glossary, and review, access the accompanying DVD-ROM in this book.

DVD-ROM Highlights▼

Labeling Exercise
A picture is worth a thousand words, but
only if it’s labeled correctly. Review path-
ology by clicking and dragging the terms
that correlate to a figure from this chapter.
The correct labels will lock into place beside
the picture.

Gridlock
Are you a Jeopardy! champ? Prove your quiz
show smarts by clicking the tiles to answer
the human diseases questions hidden be-
neath. Get them all right to clear the grid.

True or False Quiz
Take advantage of the free-access online study guide
that accompanies your textbook. You’ll find a true or
false quiz that provides instant feedback and allows
you to check your score to see what you got right or
wrong. By clicking on this URL you’ll also access
links to current news articles and an audio glossary.

Website Highlights—www.pearsonhighered.com/zelman▼

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Human Diseases: A Systemic Approach, Seventh Edition, by Mark Zelman, Ph.D., Elaine Tompary, PharmD, Jill Raymond, Ph.D., Paul Holdaway, MA,
and Mary Lou Mulvihill, Ph.D. Published by Prentice Hall. Copyright © 2010 by Pearson Education, Inc.

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