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CHAPTER 26
Stomach
reconstruction as a Roux-en-Y gastrojejunostomy should be
avoided (Fig. 26-5). Although the Roux-en-Y operation is an
excellent procedure for keeping duodenal contents out of the
stomach and esophagus, in the presence of a large gastric remnant, this reconstruction will predispose to marginal ulceration
and/or gastric stasis. (See Schwartz 11th ed., p. 1129.)
AB C
FIG. 26-4. A through C. Billroth II antecolic gastrojejunostomy. (Reproduced with permission from
Zinner MJ, Schwartz SI, Ellis H. Maingot’s Abdominal Operations, 10th ed. Vol. I. Stamford, CT: Appleton
& Lange; 1997.)
<50% gastric
remnant
50 to 60 cm
FIG. 26-5. Roux-en-Y gastrojejunostomy.
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11. A 78-year-old man with good functional status
undergoes evaluation for a newly diagnosed focal antral
gastric cancer including cross-sectional imaging, endoscopic ultrasound, and diagnostic laparoscopy. Studies
indicate a T2N0 tumor. The least appropriate treatment
approach is:
A. Subtotal D2 gastrectomy alone.
B. Subtotal D2 gastrectomy followed by chemotherapy.
C. Initial systemic therapy followed by subtotal D2
gastrectomy.
D. Subtotal gastrectomy with removal and assess-
ment of >16 regional lymph nodes and adjuvant
chemoradiotherapy.
E. Endoscopic resection.
12. Which of the following is not TRUE of hereditary diffuse
gastric cancer (HDGC)?
A. It is associated with a mutation in the E-cadherin
gene.
B. Lifetime risk of gastric cancer in affected women is
greater than in men.
C. It is associated with an increased risk of lobular breast
cancer.
D. Presentation with clinically significant gastric cancer
is associated with a very poor prognosis.
Answer: E
Multimodality approaches to gastric cancer have become
well entrenched with randomized studies from the United
States and Europe supporting adjuvant chemoradiotherapy
and perioperative chemotherapy approaches. Evidence from
Asia supports adjuvant chemotherapy after gastrectomy with
extended regional lymphadenectomy (ie, D2 lymphadenectomy). Although T2N0 cancers were included in some of
the randomized trials, such cases were probably underrepresented and the absolute benefit of multimodality therapy
in this context may not be as great as in the overall cohort
of patients with locally advanced disease. Selective omission
of adjuvant therapy in patients with more favorable surgical
pathology may be appropriate. T2 tumors are not well treated
with endoscopic resection given a prohibitive risk of recurrence. (See Schwartz 11th ed., pp. 1139–1149.)
Answer: B
Mutations in the E-cadherin gene (CDH1) are associated with
HDGC. The lifetime risk of gastric cancer is approximately
70% in men and 56% in women. Mutation-carrying women
are at increased risk for breast cancer, typically lobular carcinomas. Because of the poor prognosis associated with clinical gastric cancer in this setting and limitations of existing
surveillance protocols, prophylactic gastrectomy is a consideration in individuals with CDH1 mutations. (See Schwartz
11th ed., p. 1143.)
CHAPTER 26
Stomach
13. The most common premalignant condition for early
gastric cancer is:
A. Gastric adenoma.
B. Chronic ulcer.
C. Hamartomatous polyp.
D. Atrophic gastritis.
14. A patient presents with gastric cancer diagnosed on
endoscopy performed for weight loss and abdominal fullness. Cross-sectional imaging shows a diffusely
thickened stomach with regional adenopathy. There is
no evidence of distant metastatic disease. Initial management should include:
A. Diagnostic laparoscopy with peritoneal lavage.
B. Consideration of enteral access for nutrition support.
C. Systemic chemotherapy.
D. Total gastrectomy.
E. A, B, and C.
Answer: D
Some patients with atrophic gastritis develop intestinal
metaplasia in the gastric mucosa that may progress to dysplasia and then to gastric cancer. Numerous cofactors have
been implicated, including diet, altered gastric microbiome,
genetics, and hypergastrinemia. Patients with atrophic gastritis are at risk for gastric cancer and should undergo periodic endoscopic surveillance. Metaplastic atrophic gastritis
and dysplastic atrophic gastritis in particular are markers of
increased risk for gastric cancer.
By far the most common precancerous lesion is atrophic
gastritis. There is a growing appreciation of the important
influence of the chronic inflammatory milieu on the genome
of mucosal cells. Chronic inflammation leads to both genetic
and epigenetic changes in mucosal cells, which in the stomach leads to the development of gastritis-associated cancer.
(See Schwartz 11th ed., pp. 1138–1139; 1141–1142.)
Answer: E
Diagnostic laparoscopy with peritoneal lavage has emerged as
an important component of the staging of gastric cancers and
reveals microscopic or macroscopic disseminated disease in up
to 36% of cases in published series. Diffuse gastric cancers are
often diagnosed at an advanced stage. In the context of a clinical picture consistent with linitis plastica, distant metastasis
is usually present. Although gross disease may be technically
resectable with total gastrectomy, initiation of systemic therapy
is usually a more pressing priority. Enteral access and supplemental nutrition may improve candidacy for systemic therapy
in selected cases. (See Schwartz 11th ed., pp. 1139–1149.)
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15. A fifty-year-old man undergoes resection of a 5 cm gastrointestinal stromal tumor (GIST) involving the fundus
of the stomach. Pathology indicates 12 mitoses/50 HPF.
Molecular testing shows a KIT mutation. Subsequent
management should include:
A. Clinical follow-up alone.
B. Clinical follow-up with periodic surveillance imag-
ing alone.
CHAPTER 26
Stomach
C. Adjuvant Imatinib for 1 year.
D. Adjuvant Sunitinib for at least 3 years.
E. Adjuvant Imatinib for at least 3 years.
16. Which of the following options is the best initial management of a low-grade mucosa-associated lymphoid tissue (MALT) lymphoma of the gastric antrum?
A. Helicobacter pylori eradication
B. Chemotherapy +/– radiation therapy
C. Wedge resection
D. Antrectomy
Answer: E
Risk of GIST recurrence after resection reflects the location
of the tumor (gastric tumors are less likely to recur than nongastric tumors), size, and mitotic rate. Mitotic rate >5/50 HPF
is the strongest predictor of recurrence. Patients at higher risk
of recurrence should be treated with adjuvant Imatinib barring the presence of a PDGFRA D842V mutation, which is
associated with Imatinib resistance. Duration of treatment for
3 years proved superior to 1 year in the Scandinavian Sarcoma Group XV111 trial and there is increasing momentum
for indefinite treatment after resection of high-risk disease.
(See Schwartz 11th ed., pp. 1149–1151.)
Answer: A
Low-grade MALT lymphoma, essentially a monoclonal proliferation of B cells, presumably arises from a background of
chronic gastritis associated with H. pylori. These relatively
innocuous tumors then undergo degeneration to high-grade
lymphoma, which is the usual variety seen by the surgeon.
Remarkably, when the H. pylori is eradicated and the gastritis
improves, the low-grade MALT lymphoma often disappears.
Thus, low-grade MALT lymphoma is not a surgical lesion.
Careful follow-up is necessary particularly in those lesions
with a t (11:18) translocation, thought to be a risk factor for a
more aggressive MALT lesion. (See Schwartz 11th ed., p. 1149.)
17. Type III gastric carcinoid tumors:
A. Often do not require resection.
B. Are associated with hypergastrinemia.
C. Are sporadic lesions.
D. Have better outcomes than type I and II tumors.
18. In the patient with a normal liver and endoscopic diagnosis of watermelon stomach (gastric antral vascular
ectasia [GAVE]), chronic blood loss requiring multiple
transfusions is best treated by:
A. Proton pump inhibitors and Carafate.
B. Beta blockers.
C. Distal gastrectomy.
D. Total gastrectomy.
Answer: C
Type III gastric neuroendocrine tumors are sporadic. They
are most often solitary (usually >2 cm) and occur more commonly in men. They are not associated with hypergastrinemia. Most patients have regional nodal or distant metastases
at the time of diagnosis, and some present with symptoms of
carcinoid syndrome. (See Schwartz 11th ed., p. 1151.)
Answer: C
The parallel red stripes atop the mucosal folds of the distal
stomach give this rare entity its name. Histologically, gastric
antral vascular ectasia (GAVE) is characterized by dilated
mucosal blood vessels that often contain thrombi, in the
lamina propria. Mucosal fibromuscular hyperplasia and hyalinization often are present (Fig. 26-6). The histologic appearance can resemble portal hypertensive gastropathy, but the
latter usually affects the proximal stomach, whereas watermelon stomach predominantly affects the distal stomach.
FIG. 26-6. Gastric antral vascular ectasia (watermelon
stomach). (Reproduced with permission from Godlman H,
Hayek J, Federman M. Gastrointestinal Mucosal Biopsy.
New York, NY: Churchill Livingstone; 1996.)
19. Treatment for severe early dumping after gastrectomy
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that is persistent despite an antidumping diet and fiber is:
A. Expectant management.
B. Oral glucose for symptoms.
C. Octreotide.
D. Surgical conversion to a Roux-en-Y drainage.
Beta blockers and nitrates, useful in the treatment of portal
hypertensive gastropathy, are ineffective in patients with gastric antral vascular ectasia. Patients with GAVE are usually
elderly women with chronic gastrointestinal (GI) blood loss
requiring transfusion. Most have an associated autoimmune
connective tissue disorder, and at least 25% have chronic
liver disease. Nonsurgical treatment options include estrogen
and progesterone, and endoscopic treatment with the neodymium yttrium-aluminum garnet (Nd:YAG) laser or argon
plasma coagulator. Antrectomy may be required to control
blood loss, and this operation is quite effective but carries
increased morbidity in this elderly patient group. Patients
with portal hypertension and antral vascular ectasia should
be considered for transjugular intrahepatic portosystemic
shunt (TIPSS). (See Schwartz 11th ed., p. 1154.)
Answer: C
A variety of hormonal aberrations have been observed in
early dumping, including increased serum levels of vasoactive
intestinal polypeptide (VIP), cholecystokinin (CCK), neurotensin, peripheral hormone peptide YY, renin-angiotensinaldosterone, and decreased atrial natriuretic peptide. Late
dumping is associated with hypoglycemia and hyperinsulinemia. Medical therapy for the dumping syndrome consists
of dietary modification and somatostatin analogue (octreotide). (See Schwartz 11th ed., p. 1157.)
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CHAPTER 26
Stomach
20. Ménétrier disease is characterized by:
A. Hypertrophic gastric folds and hypoproteinemia.
B. A tortuous submucosal congenital arteriovenous
malformation.
C. Gastric antral vascular ectasia.
D. Epithelial hyperplasia and hypergastrinemia.
Answer: A
There are two clinical syndromes characterized by epithelial hyperplasia and giant gastric folds: Zollinger-Ellison
syndrome (ZES) and Ménétrier disease. The latter is characteristically associated with protein-losing gastropathy and
hypochlorhydria. There are large rugal folds in the proximal
stomach, and the antrum is usually spared. Mucosal biopsy
shows diffuse hyperplasia of the surface mucus-secreting cells
and usually decreased parietal cells (Fig. 26-7). It has recently
been suggested that Ménétrier disease is caused by local overexpression of transforming growth factor-A in the gastric
mucosa, which stimulates the epidermal growth factor receptor, a receptor tyrosine kinase, on gastric surface epithelial
cells (SECs). This results in the selective expansion of surface
mucous cells in the gastric body and fundus. A few patients
with this unusual disease have been successfully treated with
the epidermal growth factor receptor blocking monoclonal
antibody cetuximab. (See Schwartz 11th ed., pp. 1153–1154.)
FIG. 26-7. Mucosal biopsy in Ménétrier’s disease.
(Reproduced with permission from Ming S-C, Goldman
H. Pathology of the Gastrointestinal Tract, 2nd ed.
Baltimore, MD: Williams & Wilkins; 1998.)
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CHAPTER 27
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The Surgical Management of Obesity
1. What body mass index [BMI or wt (kg)/height (m2)]
definition of obesity serves as the standard indication for
bariatric surgery when medical therapy has failed and
comorbid conditions exist?
A. Overweight (BMI 25.0–29.9)
B. Class I obesity (BMI 30.0–34.9)
C. Class II obesity (BMI 35.0-39.9)
D. Class III obesity (BMI ≥ 40)
2. Which of the following bariatric procedures is primarily
intended to induce weight loss through malabsorption of
ingested nutrients?
A. Jejunoileal bypass
B. Sleeve gastrectomy
C. Roux-en-Y gastric bypass
D. Duodenal switch
3. Complications of adjustable gastric banding which
have diminished its popularity as a bariatric procedure
include all of the following EXCEPT:
A. Mortality risk.
B. Slippage of the band.
C. Failure to lose weight.
D. Port and tubing complications.
Answer: C
A 1991 NIH Consensus Conference recommended that
bariatric surgery was indicated for a BMI of 35.0 to 39.9
when medical therapy has failed and comorbid conditions
exist. When no comorbid conditions exist, a BMI of ≥40 is
required. This standard continues to be used by insurers,
although recent studies have shown benefit in lower BMI
groups. (See Schwartz 11th ed., pp. 1169–1170 and Table 27-2
p. 1175.)
Answer: A
Bariatric procedures are classified as restrictive, malabsorptive, or a combination of restrictive and malabsorptive in
the mechanism of weight loss that they induce. Restrictive
operations include adjustable gastric band and gastric sleeve,
malabsorptive operations include jejunoileal bypass and its
derivatives, and combined restrictive and malabsorptive procedures include the Roux-en-Y gastric bypass. (See Schwartz
11th ed., p. 1168.)
Answer: A
The adjustable gastric band procedure, usually performed
laparoscopically, has the lowest cost and mortality risk of all
the bariatric procedures, but is the least effective for weight
loss. In addition, slippage and erosion of the band and complications related to the maintenance and use of the port for
adjusting the size of the band contribute to its loss of popularity. (See Schwartz 11th ed., p. 1188.)
4. Early postoperative complications after a Roux-en-Y
gastric bypass (RYGB) procedure include all of the following EXCEPT:
A. Hematemesis.
B. Dilation of the distal gastric remnant.
C. Pulmonary embolus.
D. Hyperglycemia.
Answer: D
Early postoperative complications after RYGB include
hematemesis due to bleeding from the gastrojejunal staple
or suture line, gastric remnant dilation due to down-stream
obstruction, and pulmonary complications such as atelectasis and pulmonary embolus. Diabetes, if present, usually
improves promptly after RYGB and hyperglycemia is unlikely
to be problematic. (See Schwartz 11th ed., p. 1185.)
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5. Small bowel obstruction after Roux-en-Y gastric bypass
(RYGB) should be treated as an urgent surgical emergency because:
A. It is frequently due to an incarcerated internal hernia
which can progress to bowel necrosis and perforation.
B. Abdominal distension risks disruption of suture lines.
C. Signs and symptoms of peritonitis, such as pain, fever,
and leukocytosis, are usually masked in the obese.
CHAPTER 27
The Surgical Management of Obesity
D. Nasogastric intubation will not decompress the distal
gastric remnant.
6. A late complication of Roux-en-Y gastric bypass is
the development of post-gastric bypass hypoglycemia
(PGBH) due to inappropriately elevated insulin levels.
Recommended treatments of this condition include all
of the following EXCEPT:
A. Very low carbohydrate diet.
B. Anti-secretory agents such as diazoxide and
somatostatin.
C. GLP-1 receptor antagonists.
D. Pancreatic resection.
Answer: A
Small bowel obstruction after RYGB is frequently due to an
incarcerated internal hernia at the location of the closure, or lack
thereof, of the mesenteric defect. This can progress rapidly to
strangulation and necrosis of the bowel with subsequent perforation. Adverse outcomes with this complication have resulted
in the uniform recommendation that small bowel obstruction in this setting should be regarded as a surgical emergency.
Abdominal distention and difficulties with nasogastric intubation are not relevant concerns. (See Schwartz 11th ed., p. 1184.)
Answer: D
PGBH occurs in some patients after Roux-en-Y gastric bypass
due to exaggerated or excessive insulin levels. It is thought to
be a consequence of greatly increased GLP-1 levels seen in
some patients. A very low carbohydrate diet may provide relief
in some patients, and diazoxide and somatostatin have been
used in those who fail diet therapy. Recently GLP-1 receptor antagonists have been reported to be successful. Although
pancreatic resection was initially reported in patients with
severe hypoglycemia, it is no longer recommended. Partial
pancreatectomy results in a recurrence of the problem, and
total pancreatectomy exchanges one severe condition for
another. (See Schwartz 11th ed., pp. 1204–1205.)
7. Complications which are associated with the gastric
sleeve procedure include:
A. Leak from the gastric staple line.
B. Gastroesophageal reflux.
C. Stenosis of the gastric sleeve.
D. All of the above.
8. In addition to the effects of weight loss, the resolution of
type 2 diabetes mellitus after the gastric sleeve procedure
and Roux-en-Y gastric bypass (RYGB) is thought to be
contributed to by:
A. Reduced ghrelin production.
B. Increased secretion of GLP-1.
C. Appetite suppression.
D. All of the above.
9. Adolescent patients with morbid obesity are increasingly
being referred for consideration of bariatric procedures
due to failure of medical management and the risks
associated with a lifetime of obesity. What nutritional
deficiencies require lifelong treatment after Roux-enY gastric bypass (RYGB), the most common procedure
performed in this age group?
A. Pernicious anemia due to vitamin B12 deficiency
B. Iron deficiency anemia
C. Deficiencies of vitamins A, E, D, and K
D. All of the above
Answer: D
The gastric sleeve procedure creates a high pressure tube.
This places the gastric staple line at risk for leak, and additional buttress sutures are frequently used to reinforce the
staple line. The high pressure also increases the probability
of gastroesophageal reflux disease (GERD) so patients with a
history of GERD are less favorable candidates for the gastric
sleeve procedure. The gastric tube itself is usually constructed
over a 40-French bougie. If a smaller bougie is used, the risk
of leak and reflux are increased and stenosis of the gastric
sleeve or tube may occur. (See Schwartz 11th ed., p. 1186.)
Answer: D
Gastrectomy removes much of the ghrelin-producing portion
of the stomach and this mechanism is thought to contribute
to weight loss after both gastric sleeve and RYGB procedures.
GLP-1, the enteric hormone which augments insulin release,
is dramatically increased after RYGB, and is increased after
the gastric sleeve procedure as well. A profound suppression
of appetite and food craving has been found to follow these
procedures, presumably due to the altered hormonal status of
peptides which affect the satiety centers of the central nervous
system. (See Schwartz 11th ed., p. 1175.)
Answer: D
Loss of intrinsic factor produced in the gastric fundus,
impaired iron absorption, and a deficiency of the fat-soluble
vitamins present lifelong risks after RYGB and other malabsorptive bariatric procedures. Vitamin replacement and
nutritional monitoring are therefore mandatory in bariatric
patients. (See Schwartz 11th ed., pp. 1191–1192.)
CHAPTER 28
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Small Intestine
1. How long is the small intestine?
A. 4 to 6 ft
B. 10 to 12 ft
C. 4 to 6 m
D. 10 to 12 m
2. Which of the following features is characteristic of the
ileum, as opposed to the jejunum?
A. The presence of valvulae conniventes
B. The presence of Peyer patches
C. Larger vasa recta
D. Less fatty mesentery
3. A pocket- or sock-like outpouching on the antimesenteric side of the distal ileum, called a Meckel diverticulum, is caused by:
A. Excessive traction on the intestine during childbirth.
B. Increased intraluminal pressure.
C. A persistent vitelline duct.
D. A mutation of the c-Mec gene.
4. The most common presentations of symptomatic Meckel
diverticuli include all of the following EXCEPT:
A. Bleeding.
B. Intestinal obstruction.
C. Inguinal pain.
D. Diverticulitis.
Answer: C
The small intestine’s length varies depending on whether
radiologic, surgical, or autopsy measurements are made,
but it is thought to measure 4 to 6 m in living subjects.
(See Schwartz 11th ed., p. 1219.)
Answer: B
The entire small intestine contains valvulae conniventes,
also known as plicae circularis. The jejunum has larger vasa
recta, a larger diameter, and a less fatty mesentery. The ileum
contains prominent lymphoid follicles called Peyer patches.
(See Schwartz 11th ed., p. 1220.)
Answer: C
The embryonic gut communicates with the yolk sac by mean
of the vitelline duct. Failure of this structure to obliterate
by the end of gestation can result in a Meckel diverticulum.
(See Schwartz 11th ed., pp. 1246–1247.)
Answer: C
Bleeding, intestinal obstruction, and diverticulitis are the
most common presenting symptoms of Meckel diverticuli.
Most are discovered incidentally at surgical procedures.
Inguinal pain is not a typical symptom. (See Schwartz
11th ed., p. 1247.)
5. How much fluid normally enters the adult small intestine each day?
A. 2 L
B. 4 L
C. 6 L
D. 8 L
Answer: D
About 8 to 9 L of fluid enters the small intestine daily, of
which over 80% is absorbed. This includes 2 L from oral
intake, 1.5 L of saliva, 2.5 L of gastric juice, 1.5 L of biliopancreatic secretions, and 1 L of fluid secreted by the small
intestine. (See Schwartz 11th ed., p. 1222.)
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6. How are the digestion products of carbohydrates, such
as glucose, galactose, and fructose, absorbed through the
intestine?
A. By passive diffusion across enterocyte plasma
membranes
B. By facilitated diffusion via specific transporters such
as SGLT1, GLUT2, and GLUT5
C. By endocytosis of enterocytes on the villus
CHAPTER 28
Small Intestine
D. By facilitated diffusion through tight junctions
between enterocytes
7. What does the “enterohepatic circulation” refer to?
A. The superior mesenteric—portal venous circuit
B. The secretion of cholesterol in the bile and its reab-
sorption in the distal ileum
C. The secretion of bile acids by the liver and their reab-
sorption in the distal ileum
D. The secretion of cholecystokinin by the jejunum and
its stimulation of bile flow
8. Components of the gut-associated lymphoid tissue
(GALT) include all of the following EXCEPT:
A. Plasma cells.
B. Stellate cells.
C. Dendritic cells.
D. CD4+ and CD8+ T cells.
Answer: B
The three terminal products of carbohydrate digestion are
transported through the enterocyte brush border membrane
via facilitative transporter proteins such as the sodiumglucose co-transporter 1 (SGLT1), glucose transporter 2
(GLUT2) and glucose transporter 5 (GLUT5). There is
evidence of overexpression of these transporters, particularly SGLT1, in diabetes and obesity, and new therapeutic
approaches for these conditions are designed to inhibit these
transporters. (See Schwartz 11th ed., p. 1223.)
Answer: C
Bile acids act as detergents which increase the solubility
of lipid micelles which are taken up by the brush border
membrane of the jejunum, where >90% of fat is absorbed.
The bile acids themselves remain in the intestinal lumen
and are reabsorbed in the distal ileum where they enter
the portal venous circulation and are resecreted in the bile.
(See Schwartz 11th ed., p. 1225.)
Answer: B
The GALT includes Peyer patches, which are microscopic
aggregates of B-cell follicles and intervening T-cell areas
found in the lamina propria of the small intestine, primarily in the distal ileum. IgA-producing plasma cells and dendritic cells populate these regions and serve to protect against
microbes and foreign pathogens. Stellate cells, which produce
collagen when activated, are not contained within the GALT.
(See Schwartz 11th ed., p. 1226.)
9. The radiologic evaluation of a suspected small bowel
obstruction may require use of a contrast agent to confirm the location and possible etiology of the obstruction. Water-soluble contrast agents, such as gastrograffin,
are preferable to barium for all of the following reasons
EXCEPT:
A. Gastrograffin is safer than barium if a perforation has
occurred.
B. Gastrograffin may facilitate the resolution of a partial
small bowel obstruction.
C. Gastrograffin small bowel studies are easier to
perform.
D. Gastrograffin may detect subtle mucosal abnormali-
ties more sensitively than barium.
10. A closed loop obstruction is particularly dangerous
because:
A. Intraluminal pressure rises high enough to cause
ischemia and necrosis.
B. The obstruction is painless.
C. Bacterial overgrowth results in sepsis.
D. The obstructive segment is not apparent on imaging
studies.
Answer: C
Water-soluble contrast agents, such as gastrograffin, are less
likely to provoke peritonitis if a perforation has occurred and
may be more sensitive in the detection of mucosal abnormalities. Gastrograffin has also been shown to be therapeutic for
the treatment of partial small bowel obstruction, but gastrograffin studies take longer and are more labor-intensive to
perform. (See Schwartz 11th ed., pp. 1229–1231.)
Answer: A
A closed loop obstruction, in which an intestinal segment is
obstructed both proximally and distally, as in a volvulus, is
particularly dangerous because intraluminal pressure rises
quickly and can cause venous congestion and arterial obstruction which leads to necrosis of the intestinal wall and perforation. It classically presents with “pain out of proportion to
the physical exam,” and is usually apparent on CT scan which
frequently shows a U-shaped or C- shaped dilated bowel loop
associated with a radial distribution of mesenteric vessels
converging toward a torsion point. (See Schwartz 11th ed.,
p. 1229.)
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11. Therapy of a small bowel obstruction usually consists of
prompt surgical correction. In patients with no evidence
of closed loop obstruction, and in whom there is no fever
or leukocytosis or tachycardia, a period of careful observation with nasogastric decompression may be successful in all of the following conditions EXCEPT:
A. Partial small bowel obstruction.
B. Obstruction in the early postoperative period.
C. Obstruction due to Crohn disease.
D. Obstruction due to an internal hernia.
12. Laparoscopic surgery for bowel obstruction may be preferable to open surgery for all of the following reasons
EXCEPT:
A. Laparoscopic surgery is associated with fewer wound
infections and a shorter length of hospital stay.
B. Laparoscopic surgery is preferable in cases where a
single adhesive band is causing the obstruction.
C. Laparoscopic surgery is less likely to produce fur-
ther adhesion formation which may cause recurrent
obstruction.
D. The risk of iatrogenic bowel injury is higher with
laparoscopic surgery.
13. Crohn’s disease affects the small intestine in 80% of
cases, and the colon alone in 20%. Isolated perineal and
anorectal disease occurs in 5% to 10% of patients. In addition, extraintestinal manifestations of Crohn’s disease
occur in up to 25% of patients and may include which of
the following?
A. Erythema nodosum
B. Interstitial lung disease
C. Nephrolithiasis
D. All of the above
Answer: D
Partial small bowel obstruction and early postoperative
obstruction can mimic ileus and may respond to nonoperative therapy. Crohn disease usually responds to medical
therapy, although recurrent obstruction is an indication for
surgical correction. Obstruction due to an internal hernia
requires prompt surgical intervention to avoid strangulation
and necrosis. (See Schwartz 11th ed., p. 1231.)
Answer: D
The use of laparoscopic surgery for small bowel obstruction
has been found to be highly successful when the obstruction
is caused by a single adhesive band. The avoidance of an open
procedure also reduces the risk of subsequent adhesion formation. The morbidity risks of laparoscopic surgery are less
than with open surgery and the risk of iatrogenic injury to the
bowel is similar. (See Schwartz 11th ed., p. 1232.)
Answer: D
Extraintestinal manifestations of Crohn’s disease are diffuse
and can involve dermatologic, rheumatologic, ocular, hepatobiliary, urologic, and pulmonary conditions. (See Schwartz
11th ed., p. 1237.)
CHAPTER 28
Small Intestine
14. The primary genetic defect associated with Crohn’s disease is a mutation of the NOD2 gene on chromosome 16.
This gene encodes for a protein product which:
A. Mediates the innate immune response to microbial
pathogens.
B. Activates stellate cells to produce collagen.
C. Regulates the rate of crypt-to-villus enterocyte
migration.
D. Mediates the production of enterocyte alkaline
phosphatase.
15. In the resection of a stenotic area of intestine in a patient
with Crohn’s disease, the best approach is:
A. A resection margin of 2 cm from gross disease.
B. A resection margin of 12 cm from gross disease.
C. A resection margin of 2 cm from microscopic disease
on frozen section.
D. A resection margin of 12 cm from microscopic
disease on frozen section.
Answer: A
The protein product of the NOD2 gene mediates the innate
immune response to microbial pathogens. A variety of defects
in immune regulatory mechanisms such as over responsiveness of mucosal T cells to enteric flora-derived antigens can
lead to defective immune tolerance and sustained inflammation. (See Schwartz 11th ed., p. 1236.)
Answer: A
There are no differences in the recurrence rates for resection
with a 2 cm margin or a 12 cm margin from gross disease.
The additional bowel lost may contribute to eventual short
gut syndrome in a patient who requires multiple resections,
so minimizing bowel loss is a priority. There is no benefit to
achieving frozen section negative margins in the resection
of Crohn’s strictures; positive margin resections have the same
recurrence rate as negative margin resections. The effort
to obtain a frozen section negative margin carries the risk
of removing more intestine than is necessary. (See Schwartz
11th ed., p. 1239.)
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