gallbladder disease. Dietary fiber helps absorb cho-
lesterol from consumed foods, reducing the
amount of cholesterol that becomes available in
the bloodstream and for the liver to process.
See also DIET AND HEALTH; ENDOSCOPY; HYPERLIPI-
DEMIA; LIFESTYLE AND HEALTH; MINIMALLY INVASIVE SUR-
GERY; PRIMARY BILIARY CIRRHOSIS; PRIMARY SCLEROSING
CHOLANGITIS.
gastrectomy Partial or complete surgical
removal of the STOMACH, typically to treat STOMACH
CANCERor uncontrollable bleeding resulting from
PEPTIC ULCER DISEASE. Gastrectomy is a major OPERA-
TION, typically an OPEN SURGERY, performed under
general ANESTHESIAthat requires several days to a
week in the hospital and 8 to 12 weeks for total
recovery and return to regular activities. An indi-
vidual’s course of recovery depends on the reasons
for the surgery. The surgical operation takes two
to three hours. After removing the diseased por-
tion of the stomach through an abdominal inci-
sion at the lower edge of the left rib cage, the
surgeon connects the remaining portion of the
stomach (or the ESOPHAGUS, when the gastrectomy
is total) to the DUODENUM. A partial (also called
subtotal) gastrectomy leaves a gastric pouch that
can carry on some of the digestive functions of the
stomach. Total gastrectomy, which is less com-
mon, leaves no residual gastric pouch though the
surgeon may construct one by expanding a por-
tion of the duodenum.
Many people are able to return to normal eat-
ing habits after they recover from the surgery,
though find that they need to eat frequent small
meals to accommodate the smaller stomach and
reduce gastrointestinal distress. Foods that are
high in protein and low in simple sugars are easier
for the small intestine to digest without the aid of
the stomach. Some people have difficulty eating
regular foods after gastrectomy and need to use
NUTRITIONAL SUPPLEMENTS, typically liquid prepara-
tions, to meet their NUTRITIONAL NEEDS.
Risks and complications of gastrectomy include
bleeding, INFECTION, dumping syndrome (RAPID
GASTRIC EMPTYING), and damage to the vagus NERVE
(which regulates gastric PERISTALSIS and other
digestive functions). People who have total gas-
trectomies, and many people who have subtotal
gastrectomies, need regular injections of vitamin
B 12 (cyanocobalamin) because the gastric mucosa
is no longer able to produce intrinsic factor, a
chemical substance that allows the SMALL INTESTINE
to absorb this vital nutrient. Vitamin B 12 defi-
ciency causes pernicious ANEMIA.
See alsoBARIATRIC SURGERY; CANCER TREATMENT
OPTIONS AND DECISIONS; CRANIAL NERVES; SURGERY BEN-
EFIT AND RISK ASSESSMENT.gastritis INFLAMMATIONof the lining of the STOM-
ACH. There are two broad classifications of gastritis:
erosive and nonerosive. The most common cause
of erosive gastritis is repeated irritation from
ingested substances such as ALCOHOL, aspirin, and
NONSTEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDS).
The most common cause of nonerosive gastritis is
INFECTION with HELICOBACTER PYLORI, the strain of
BACTERIAthat causes PEPTIC ULCER DISEASE. Occa-
sionally viral infections can cause acute gastritis,
which resolves when the infection runs its course.
Autoimmune gastritis, in which the IMMUNE SYSTEM
attacks the cells that form the mucosal lining of
the stomach, interferes with the absorption of cer-
tain NUTRIENTS, notably vitamin B 12 (pernicious
ANEMIA).
Symptoms include DYSPEPSIA (upset stomach),
PAIN, NAUSEA, VOMITING, and a sensation of fullness.
The diagnostic path may include BARIUM SWALLOW
and endoscopic examination of the ESOPHAGUS,
stomach, and DUODENUM (first segment of the
SMALL INTESTINEand the site of peptic ulcer dis-
ease). The gastroenterologist may biopsy samples
of stomach tissue. Treatment targets the underly-
ing cause. Eliminating ingestion of the responsible
substance often ends erosive gastritis. ANTIBIOTIC
MEDICATIONScan eradicate H. pylori. Treatment for
autoimmune gastritis focuses on countering any
NUTRITIONAL DEFICIENCYthat results as well as elimi-
nating other sources of irritation to minimize gas-
tric inflammation.
See also AUTOIMMUNE DISORDERS; COLITIS;
ENDOSCOPY; GASTROENTERITIS; PANCREATITIS; STOMACH
CANCER.gastroenteritis INFLAMMATIONof the SMALL INTES-
TINE. The most common cause of gastroenteritis is
viral INFECTION, though sometimes BACTERIAor PAR-
ASITESare responsible. The inflammation of the
intestinal mucosa (mucus lining of the intestinal48 The Gastrointestinal System