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U N I T 8
Gastrointestinal and Hepatobiliary Function
■■
Peritonitis is an inflammatory response of the
serous membrane that lines the abdominal
cavity and covers the visceral organs. It can be
caused by bacterial invasion or chemical irritation
resulting from perforation of the viscera or
abdominal organs.
■■
Malabsorption results from the impaired
absorption of nutrients and other dietary
constituents. It can involve a single dietary
constituent, such as vitamin B
12
, or extend to
involve all of the substances absorbed in a
particular part of the small intestine. Malabsorption
can result from diseases of the small bowel and
disorders that impair digestion and, in some cases,
obstruction of lymph flow can interfere with the
transport of fats into the general circulation. Celiac
disease is an immune-mediated disorder triggered
by ingestion of gluten-containing grains (including
wheat, barley, and rye).
■■
Colorectal cancer, the second most common fatal
cancer, is seen most commonly in persons older
than 50 years of age. Most, if not all, cancers of the
colon and rectum arise in preexisting adenomatous
polyps. Programs that provide careful follow-up for
persons with adenomatous polyps and removal of
all suspect lesions have substantially reduced the
incidence of colorectal cancer.
SUMMARY CONCEPTS
(continued)
R E V I EW E X E R C I S E S
1.
A 40-year-old man reports to his health care provider
complaining of “heartburn” that occurs after eating
and also wakens him at night. He is overweight,
admits to enjoying fatty foods, and usually lies down
on the sofa and watches TV after dinner. He also
complains that lately he has been having a cough and
some wheezing. A diagnosis of GERD was made.
A.
Explain the cause of heartburn and why it
becomes worse after eating.
B.
Persons with GERD are advised to lose weight,
avoid eating fatty foods, remain sitting after
eating, and sleep with their head slightly elevated.
Explain the possible relationship between these
situations and the occurrence of reflux.
C.
Explain the possible relationship between GERD
and the respiratory symptoms this man is having.
2.
A 36-year-old woman who has been taking aspirin
for back pain experiences a sudden episode of
tachycardia and feeling faint, accompanied by the
vomiting of a coffee-ground emesis and the passing
of a tarry stool. She relates that she has not had any
signs of a “stomach ulcer” such as pain or heartburn.
A.
Relate the mucosal protective effects of
prostaglandins to the development of peptic
ulcer associated with aspirin or NSAID use.
B.
Explain the apparent suddenness of the bleeding
and the fact that the woman did not experience
pain as a warning signal.
C.
Among the results of her initial laboratory tests
is an elevated blood urea nitrogen (BUN) level.
Explain the reason for the elevated BUN.
3.
A 29-year-old woman has been diagnosed with
Crohn disease. Her medical history reveals that she
began having symptoms of the disease at 24 years
of age and that her mother died of complications
of the disease at 54 years of age. She complains of
diarrhea and chronic cramping abdominal pain.
A.
Define the term
inflammatory bowel disease
and
compare the pathophysiologic processes and
manifestations of Crohn disease and ulcerative
colitis.
B.
Describe the possible association between
genetic and environmental factors in the
pathogenesis of Crohn disease.
C.
Relate the use of the monoclonal antibody
infliximab to the pathogenesis of the
inflammatory lesions that occur in Crohn
disease.
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.
niddk.nih.gov/AboutNIDDK/ReportsAndStrategicPlanning/
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