311. A patient with diabetes mellitus presents with gastroesophageal reflux
disease accompanying gastroparesis. Which of the following statements
about gastric emptying is correct?
a. Solids empty more rapidly than liquids
b. Meals containing fat empty fa
311. The answer is c. (Ganong, pp 480-482, 494-496. Kasper et al.,
pp 220-221, 1726, 2166. Stead et al., pp 109-110. Widmaier et al., pp
597-599.) Gastroparesis is delayed emptying of food from the stomach, and
is a common cause of gastroesophageal reflux
312. A 27-year-old female medical student with irritable bowel syndrome
(IBS) has an alteration in intestinal motility resulting in fluctuating constipation
and diarrhea. Her condition has worsened in the past month as the
date she has scheduled for her l
312. The answer is e. (Ganong, pp 480-482, 506-507.) Contractile activity
in the small intestine is initiated in response to distention of the bowel
wall. Three types of smooth muscle contractions contribute to small
intestinal motility�peristalsis, segme
313. An 18-year-old male with pernicious anemia lacks intrinsic factor,
which is necessary for the absorption of cyanocobalamin. Vitamin B12 is
absorbed primarily in which portion of the GI tract?
a. Stomach
b. Duodenum
c. Jejunum
d. Ileum
e. Colon
313. The answer is d. (Ganong, pp 313, 315, 477, 496. Kasper et al.,
pp 602-604. Stead et al., pp 150-151.) Most vitamins are absorbed in the
upper small intestine, but vitamin B12 (cobalamin) is absorbed primarily in
the terminal ileum. In the stomach, v
314. A 57-year-old man undergoes resection of the distal 100 cm of the
terminal ileum as part of treatment for Crohn's disease. The patient likely
will develop malabsorption of which of the following?
a. Iron
b. Folate
c. Lactose
d. Bile salts
e. Protein
314. The answer is d. (Ganong, pp 474-475, 507.) The terminal ileum
contains specialized cells responsible for the absorption of primary and
secondary bile salts by active transport. Bile salts are necessary for adequate
digestion and absorption of fat. R
315. A 42-year-old salesman presents with the chief complaint of intermittent
midepigastric pain that is relieved by antacids or eating. Gastric
analysis reveals that basal and maximal acid output exceed normal values.
The gastric acid hypersecretion can
315. The answer is c. (Ganong, pp 484-496.) Increases in basal and maximal
acid output are suggestive of inflammation or removal of the proximal
small intestine. Intestinal receptors monitor the composition of chyme and
elicit feedback mechanisms that reg
316. A 27-year-old female comes to the emergency room because of a
2-day bout of profuse watery diarrhea. Physical examination reveals dry
lips and oropharynx. The patient is diagnosed with acute secretory diarrhea
and dehydration, likely due to Escherich
316. The answer is b. (Ganong, p 512. Stead et al., pp 139-141.) Diarrhea
is the abnormal passage of fluid or semisolid stool with increased frequency.
The general approach to the primary evaluation of patients with
diarrhea is differentiating between an
317. A 37-year-old male presents with dehydration and hypokalemic
metabolic acidosis. This acid-base and electrolyte disorder can occur with
excess fluid loss from which of the following organs?
a. Stomach
b. Ileum
c. Colon
d. Pancreas
e. Liver
317. The answer is c. (Ganong, pp 475-477, 491-492. Kasper et al.,
pp 263-268.) Loss of gastric juice results in hypokalemic, metabolic alkalosis.
Excessive loss of fluid from the gastrointestinal tract can lead to dehydration
and, depending on the origin
318. A 49-year-old man undergoes vagotomy for his peptic ulcer disease.
As a result, which of the following gastrointestinal motor activities will be
affected most?
a. Secondary esophageal peristalsis
b. Distention-induced intestinal segmentation
c. Orad
318. The answer is c. (Ganong, pp 494-495.) Orad stomach accommodation
depends exclusively on an intact vago-vagal reflex. Vagal innervation
of the gastrointestinal tract extends from the esophagus to the level of the
transverse colon. Preganglionic fiber
319. A 35-year-old male smoker presents with burning epigastric pain
that is most pronounced on an empty stomach. A paroxysmal rise in serum
gastrin in response to intravenous secretin further supports a diagnosis of
Zollinger-Ellison syndrome. Normally,
319. The answer is d. (Ganong, pp 484-488, 494-496.) Alkalinization of
the antrum releases the gastrin-containing cells from the inhibitory influences
of somatostatin and increases acid secretion. Acidification of the antrum promotes the release of somato
320. A 42-year-old male develops a gastric carcinoma affecting the proximal
third of his stomach. He is scheduled for a partial gastrectomy of the
affected region, which will primarily affect which of the following processes?
a. Accommodation
b. Peristals
320. The answer is a. (Ganong, pp 480, 494, 506.) Increases in intragastric
volume normally are not associated with large increases in intragastric
pressure because of distention-mediated activation of a vago-vagal inhibitory
reflex, called receptive rela
321. A 68-year-old woman with rheumatoid arthritis, who has been taking
nonsteroidal anti-inflammatory drugs (NSAIDS) for the past 10 years,
complains of burning epigastric pain that is relieved by antacids, but worsened
with food. Her doctor discontinues
321. The answer is a. (Ganong, pp 493-496.) Histamine (H2) receptor
antagonists inhibit both gastrin-induced and vagal-mediated secretion of
acid. Secretion of acid by gastric parietal (oxyntic) cells involves stimulation
of adenyl cyclase and cyclic AMP-
322. A 37-year-old male with AIDS presents with a fever, anorexia, weight
loss, and GI bleeding. Physical examination reveals a palpable abdominal
mass. Endoscopy and biopsy reveal a small-bowel malignancy, indicating surgical
resection. Removal of proxim
322. The answer is e. (Kasper et al., pp 531-532.) Inflammation or
removal of the upper small intestine leads to a decrease in pancreatic and
hepatobiliary function. The proximal small intestine contains a number of
"receptors" that monitor the physical (
323. A 63-year-old female is diagnosed with an intractable duodenal
ulcer. After consultation with a surgeon, it is recommended that she undergoes
a parietal cell vagotomy. Subsequently the patient experiences nausea
and vomiting after ingestion of a mixe
323. The answer is b. (Ganong, p 494.) The vagus nerve is the primary
neural mediator of gastric function. Activation of distension-mediated
vago-vagal reflexes in response to the presence of food in the stomach will
(1) increase gastric compliance (recep
324. A 17-year-old male who is being treated with the macrolide antibiotic
erythromycin complains of nausea, intestinal cramping, and diarrhea. The
side effects are the result of the antibiotic binding to receptors on GI tract
enteric nerves and smooth-mu
324. The answer is d. (Ganong, pp 96, 483-487.) Motilin is the gastrointestinal
peptide hormone associated with the initiation of migrating motor
complexes during the interdigestive period. The hormone stimulates
increased contractions by a direct action
325. A 23-year-old woman complains of abdominal cramps and bloating
that are relieved by defecation. Subsequent clinical evaluation reveals an
increased maximal acid output, decreased serum calcium and iron concentrations,
and microcytic anemia. Inflammat
325. The answer is b. (Ganong, pp 484, 496, 504-505. Stead et al.,
pp 149-154.) Inflammation of the duodenum may lead to increased acid
output, hypocalcemia, and microcytic anemia. Increased basal and maximal
acid outputs may result from excessive stimula
326. Gastric emptying studies performed on a 49-year-old female reveal
a time to one-half emptying of liquids of 18 min (normal <20 min) and a
time to one-half emptying of solids to be 150 min (normal <120 min).
Which of the following best explains the da
326. The answer is c. (Ganong, pp 494-495.) The emptying of solids from
the stomach is determined by the strength of antral peristaltic contractions
and the resistance offered by the pyloric sphincter. Either a decrease in the amplitude of the antral cont
327. A 57-year-old female undergoes resection of the terminal ileum as
part of treatment for her chronic inflammatory bowel disease. Removal of
the terminal ileum will most likely result in which of the following?
a. Increased bile acid concentration in t
327. The answer is c. (Ganong, pp 474-475, 507.) Removal of the terminal
ileum can lead to diarrhea and steatorrhea. The terminal ileum contains
specialized cells responsible for the absorption of primary and secondary
bile salts by active transport. Bile
328. A 67-year-old male with a history of alcohol abuse presents to the
emergency room with severe epigastric pain, hypotension, abdominal distension,
and diarrhea with steatorrhea. Serum amylase and lipase are found
to be greater than normal, leading to
328. The answer is d. (Ganong, pp 473-475.) The process of fat digestion
begins in the stomach and is completed in the proximal small intestine,
predominately by enzymes synthesized and secreted by the pancreatic acinar
cells. The major lipolytic pancreat
329. A 53-year-old male complains of a mild chronic cough and heartburn.
Esophageal manometric and endoscopic evaluation reveal a hypotensive
lower esophageal sphincter (LES) pressure and mild gastroesophageal reflux.
Which of the following is the primary
329. The answer is d. (Stead et al., pp 109-110.) The lower esophageal
sphincter is a high-pressure zone that exists between the esophageal body
and the gastric fundus. The high pressure limits reflux of gastric contents
into the esophageal body. Although
330. A patient presents with a chronic cough. The history and physical
findings rule out postnasal drip, asthma, and other pulmonary disease. Upon
questioning, the patient also reports substernal burning pain that is most
pronounced after ingestion of cof
330. The answer is d. (Ganong, pp 232, 489-490. Kasper et al., pp 205-207,
222-224, 1742-1743. Stead et al., pp 109-110. Widmaier et al., pp 593.)
Delayed gastric emptying, hiatal hernia, and decreased esophageal motility
are all causes of GERD, but the m
331. A 42-year-old male is referred to a gastroenterologist for evaluation of
refractory peptic ulcer disease. Subsequent endoscopic and laboratory data
are suggestive of Zollinger-Ellison syndrome. The increased basal acid output
and maximal acid output
331. The answer is d. (Kasper et al., pp 222, 1758-1760, 2222-2233. Stead
et al., pp 111-113, 233.) Zollinger-Ellison (ZE) has a triad of peptic ulcer
disease, gastric acid hypersecretion, and an elevated gastrin level. In ZE,
a pancreatic acinar cell ade
332. A 63-year-old woman presents with diarrhea, abdominal pain,
and flushing. The urinary excretion of the seratonin metabolite,
5-hydroxyindoleacetic acid (5-HIAA) is elevated. Abdominal CT reveals
a tumor in the terminal ileum. Surgical resection of th
332. The answer is b. (Ganong, pp 505-506. Kasper et al., pp 2220-2226.)
Removal of the terminal ileum can lead to diarrhea and steatorrhea. The terminal
ileum contains specialized cells responsible for the absorption of primary
and secondary bile salts b
333. Which of the following vitamins is both synthesized by intestinal
bacteria and absorbed in significant quantities?
a. Vitamin B6
b. Vitamin K
c. Thiamine
d. Riboflavin
e. Folic acid
333. The answer is e. (Ganong, pp 477-478.) Folic acid is both produced
in the intestine and absorbed from the intestine. In humans, several vitamins, including vitamin K, several of the B complex, and folic acid, are synthesized
by intestinal bacteria. H
334. A 70-year old woman presents with abdominal pain, microcytic
anemia, and weight loss. Colonoscopy with biopsy confirms colon cancer.
Which of the following statements about the colon is correct?
a. Absorption of Na+ in the colon is under hormonal (al
334. The answer is a. (Ganong, pp 475-477.) Both the absorption of Na+
and secretion of K+ from the colon are affected by changes in circulating
levels of aldosterone. The major route of absorption of sodium in the colon
is electrogenic transport. Because
335. A patient's abdominal pain is subdued after eating. Which of the following
is true regarding contraction of the gallbladder following a meal?
a. It is inhibited by a fat-rich meal
b. It is inhibited by the presence of amino acids in the duodenum
c. I
335. The answer is d. (Ganong, pp 483-487, 500-503.) Cholecystokinin is
released from the upper small intestine in response to partially hydrolyzed
dietary lipids and proteins and promotes gallbladder emptying. Gallbladder
contraction and sphincter of Odd
336. A 42-year-old airline pilot presents to his family physician with a
chief complaint of midepigastric pain that is relieved by antacids or eating.
Endoscopic evaluation reveals the presence of a duodenal ulcer. Based on
the diagnosis, which of the fol
336. The answer is b. (Ganong, pp 504-508.) Inflammation of the proximal
small intestine results in a decrease in the feedback regulation of gastric
function by reducing the input of the enterogastric reflex and enterogastrone
to gastric emptying and gast
337. A 26-year-old male presents to the emergency room with a 48-hour
bout of diarrhea with steatorrhea. Which of the following best accounts for
the appearance of excess fat in the stool?
a. Decreased bile salt pool size
b. Delayed gastric emptying
c. De
337. The answer is a. (Ganong, pp 474-475, 507.) Steatorrhea is defined as
excess loss of fat in the stool. Numerous pathophysiological situations can
cause the loss of excess fat in the stool including a decrease in bile acid pool
size, inactivation or d
338. A 43-year-old female presents with chief complaints of bulky and
frequent diarrhea and weight loss. She experiences recurrent episodes of
abdominal distension terminated by passage of stools. Laboratory data
reveals a microcytic anemia, decreased ser
338. The answer is c. (Ganong, p 507. Kasper et al., pp 229, 1770-1172.
Stead, pp 142-143.) Gluten-sensitivity enteropathy is characterized by an
autoimmune-induced decrease in the absorptive surface area of the small
intestine. In addition to a decrease
339. A 32-year-old woman presents to the Emergency Department with
abdominal pain and diarrhea accompanied by steatorrhea. Gastric analysis
reveals a basal acid output (12 mmol/h) greater than normal (<5 mmol/h).
The steatorrhea is most likely due to whic
339. The answer is a. (Ganong, pp 473-475.) The process of fat digestion
begins in the stomach and is completed in the proximal small intestine,
predominately by enzymes synthesized and secreted by the pancreatic acinar
cells. The major lipolytic pancreat
340. A patient presents with severe inflammation of the ileum. Clinical
findings include which of the following?
a. Increased vitamin B12 absorption
b. Decreased bile acid pool size
c. Increased colon absorption of water
d. Decreased release of secretin
e
340. The answer is b. (Stead et al., pp 131-134.) Individuals with inflammatory
disease of the ileum have decreased bile acid pool size due to
decreased bile acid reabsorption. This results in reduced absorption of
dietary triglycerides and fat-soluble vi