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Complete Answer Key - Verified from Schwartz, Doherty & Harrison's

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Q1. How should partial small intestinal obstruction be treated?

• NPO (nothing by mouth)
• Nasogastric tube insertion for decompression
• IV fluids and electrolyte replacement
• Close monitoring for progression to complete obstruction

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Q9. A 30-year-old man with painless rectal bleeding mixed with mucus, intermittent diarrhea, no perianal disease. Most likely diagnosis?

• Bloody diarrhea with mucus
• Continuous lesions starting from the rectum
• No perianal disease (unlike Crohn's)
• Affects mucosa/submucosa only

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Q22. Blood pressure measurement - which statement is correct?

• Option A is FALSE: Readings obtained by physicians are actually HIGHER than those by nurses due to white coat effect
• Option B is FALSE: 24-hour or daytime ambulatory readings correlate more closely with cardiovascular outcomes than office readings
• Option C is partially true but overstated - white coat hypertension patients do NOT necessarily have higher systemic vascular resistance than normotensives
• Option D is CORRECT: White coat hypertension affects ~20% of patients with mild hypertension, and ambulatory monitoring is recommended to confirm true hypertension

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Q23. 26-year-old woman with 6-month history of bloody diarrhea, weight loss, crampy abdominal pain. First step toward diagnosis of IBD?

• A. Abdominal CT scan - useful to rule out complications but not first line for IBD diagnosis
• B. Small bowel mucosal biopsy - requires endoscopy first
• C. Upper GI endoscopy - inappropriate for lower GI symptoms
• D. Barium enema - Can show mucosal pattern, distribution, skip lesions; was classic first step
• E. Mesenteric angiography - for active GI bleeding, not IBD diagnosis

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Q24. Inflammatory process within the colon with skip areas. Rectum is spared. Most likely diagnosis?

• Skip lesions (areas of normal mucosa between inflamed segments) = hallmark of Crohn's
• Rectal sparing = strongly supports Crohn's (UC always involves the rectum)
• UC = continuous lesions from rectum upward, no skip areas
• Ischemic colitis tends to be segmental but different distribution
• Amebic dysentery usually involves cecum and ascending colon

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Q41. 78-year-old male with acute, severe abdominal pain, LLQ tenderness, LLQ mass, temp 39°C, BP 210/... No rebound tenderness. Most likely diagnosis?

• Elderly patient
• Left lower quadrant tenderness + mass (pericolonic inflammation/phlegmon)
• Fever
• No rebound tenderness (suggests localized, not generalized peritonitis)
• Sometimes called "left-sided appendicitis"

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Q51. Preferred treatment for infantile intestinal obstruction due to intussusception?

• Success rate 75-90% with air enema (now preferred over barium)
• Barium enema was the traditional standard
• Contraindications: peritonitis, perforation, hemodynamic instability, failed pneumatic reduction

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Q60. 46-year-old with melena, endoscopy shows non-bleeding gastric ulcer, chronic ibuprofen use, H. pylori antibody positive. Most appropriate long-term management (besides stopping ibuprofen)?

1. Discontinue ibuprofen (already stated)
2. Eradicate H. pylori - standard triple therapy (PPI + clarithromycin + amoxicillin x 14 days) or quadruple therapy
3. PPI therapy for ulcer healing
4. Confirm eradication with urea breath test or stool antigen at 4 weeks after treatment

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Q62. How is mechanical intestinal obstruction diagnosed?

• Plain abdominal X-ray (supine + erect): shows dilated loops of bowel, air-fluid levels, absent gas in rectum
• CT scan of abdomen: gold standard - identifies level, cause, and complications (strangulation)
• Clinical history and physical exam (A) raise suspicion but are not definitive
• WBC (C) may be elevated but not diagnostic
• Upright chest X-ray (E) detects free air (perforation) but not the obstruction itself

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Q63. 25-year-old with jaundice, returned from Mexico 2 months ago, brother died of "liver disease" age 35, AST 500, ALT 450, LDH 1000, Albumin 2.5. Hepatitis viruses negative. ANA negative. Liver biopsy: chronic active hepatitis with bridging fibrosis, iron stain normal. Most likely diagnosis?

• Young patient (25 years old)
• Family history of liver disease at young age (autosomal recessive)
• Markedly elevated transaminases with low albumin (hepatic dysfunction)
• Jaundice with neuropsychiatric clues (scleral jaundice noted)
• All hepatitis viruses negative
• ANA negative (ruling out autoimmune hepatitis)
• Iron stain normal (ruling out hemochromatosis)
• Bridging fibrosis consistent with Wilson's

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Q86. Patients exposed to which carcinogen develop liver malignancy?

• Vinyl chloride monomer exposure causes hepatic angiosarcoma (hepatic hemangiosarcoma)
• Workers in PVC manufacturing plants are at risk
• Asbestos (B) - mesothelioma, lung cancer
• Benzene (C) - leukemia (AML), aplastic anemia
• Aromatic amines (D) - bladder cancer
• Chromium (E) - lung cancer

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Q87. Carcinoma of cecum and proximal colon - which symptom is UNUSUAL?

• A. Anemia (due to occult blood loss from the wide lumen) - COMMON
• C. Right lower quadrant pain - COMMON
• D. Intestinal obstruction - LESS common (wide lumen means late obstruction) but can occur
• E. Anorexia and weight loss - COMMON

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Q88. 60-year-old woman, anemic, tires easily. Which study should be performed?

• Colon cancer is the primary concern - must be ruled out
• Iron deficiency anemia in an elderly patient requires GI evaluation
• Colonoscopy is the gold standard for evaluating colorectal neoplasia
• Barium enema was the classic complementary study

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Q89. Pathophysiology of hemorrhoidal disease involves:

• Hemorrhoids are normal vascular cushions in the anal canal
• They become symptomatic/enlarged when venous return is impaired
• Chronic constipation causes straining, which increases intra-abdominal and venous pressure
• This leads to engorgement and downward displacement of the cushions
• Other contributing factors: prolonged sitting, pregnancy, low-fiber diet

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Q111. Acute GI bleed with hematemesis, blood on NG aspirate, after resuscitation - next intervention?

• Hematemesis and blood on NG aspirate confirm an upper GI source
• After hemodynamic stabilization, urgent EGD is the diagnostic AND therapeutic standard
• EGD can identify the bleeding source AND treat it (injection, thermal therapy, clips)
• Red cell radionuclide scan (A) is for lower GI or obscure bleeding
• Proctosigmoidoscopy (B), anoscopy (C), colonoscopy (D) are for lower GI evaluation

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Q112. 52-year-old male with blood in stool, pedunculated villous adenomas in proximal colon. All are risk factors for colon carcinoma EXCEPT:

• A. Gardner's syndrome - FAP variant with extracolonic manifestations, very high cancer risk ✓
• B. Increasing age - risk rises sharply after age 50 ✓
• C. Family history of colon carcinoma ✓
• D. Familial adenomatous polyposis (FAP) - nearly 100% malignant transformation ✓
• E. High-fiber diet - PROTECTIVE (increases stool bulk, reduces carcinogen transit time)

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Q128. Relationship between adenomatous colon polyps and carcinoma - which is TRUE?

• Size >1 cm significantly increases cancer risk - correct
• A. FALSE - villous growth pattern actually has the HIGHEST cancer risk (not rarely)
• B. TRUE - size is directly proportional to malignant potential (tubular <1cm ~1%, >2cm villous ~40%)
• C. FALSE - Adenomas are common in areas of high cancer incidence (they correlate positively)
• D. FALSE - Adenomas and carcinomas share the same anatomic distribution in the colon
• E. FALSE - This describes a feature of adenomas (disordered crypt architecture) but "higher than normal" is not accurate as stated

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Q163. What is characteristic of primary peritonitis?

• E. TRUE - Gram-negative organisms (E. coli, Klebsiella) are the most common causative agents (60-70%)
• A. FALSE - Primary peritonitis in adults occurs predominantly in patients with cirrhosis and ascites, not particularly in children (secondary peritonitis is more common in children)
• B. FALSE - It predominantly occurs in cirrhotic patients with ascites, not specifically the elderly
• C. FALSE - By definition, primary/spontaneous peritonitis occurs WITHOUT a known intra-abdominal source (it IS spontaneous)
• D. FALSE - It does not originate from the liver per se

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Q165. 90-year-old female with large lump in her buttocks after defecation. Lump is red with concentric rings of mucosa around a central pit, nontender. Most likely diagnosis?

• Appears after straining/defecation
• Concentric mucosal rings (distinguishes from hemorrhoids which have radial folds)
• Red/pink mucosal surface
• Central pit or lumen visible
• Nontender (unless incarcerated)
• Common in elderly women

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Q167. 32-year-old male with 2-hour severe abdominal pain, pain worsens over bumps, rigid abdomen with voluntary and involuntary guarding. Diagnosis is acute peritonitis. Which physical finding is consistent?

• B. CORRECT - Ileus develops due to peritoneal irritation, causing absent bowel sounds and distension
• A. Rovsing's sign - specific for appendicitis (RLQ pain on LLQ palpation)
• C. Abdominal mass - not typical of peritonitis per se
• D. Murphy's sign - specific for acute cholecystitis
• E. Guaiac positive stool - indicates GI bleeding, not peritonitis

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Q78. 39-year-old female with fever, diarrhea, jaundice with encephalopathy, dilated abdomen, free air under diaphragm. PMN 300/mL in ascitic fluid, gram-negative rods, Lactate 36 mg/dL. Most likely diagnosis?

• Free air under diaphragm = pathognomonic for visceral perforation - this CANNOT occur in SBP
• Jaundice with encephalopathy = underlying liver disease with cirrhosis (likely background)
• PMN 300/mL in ascites = meets SBP criteria
• Gram-negative rods

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Q169. 32-year-old with 2-year history of upper abdominal pain, improves with antacids. Not tested for H. pylori. Best screening test for H. pylori?

• B. Urea breath test - Sensitivity ~95%, Specificity ~95%, non-invasive, cost-effective, confirms ACTIVE infection
• A. Serum/whole-blood antibody - Detects past or present infection; cannot confirm eradication; lower specificity
• C. Endoscopic biopsy - Invasive, reserved for those needing endoscopy for other reasons
• D. Endoscopic rapid urease test (CLO test) - Accurate but requires endoscopy

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Q50. 36-year-old white male, father had colon cancer at age 38. What preventive measure do you recommend?

• General population: colonoscopy at age 50
• Family history of colorectal cancer in first-degree relative: begin screening 10 years before the youngest affected family member's age OR at age 40, whichever is EARLIER
• Father had colon cancer at age 38 → Start screening at 28 years (10 years before 38)
• This patient is already 36 - screening is OVERDUE, so colonoscopy should be done NOW/soon
• Option A (age 38) would be too late given current guidelines
• Option B (sigmoidoscopy at 40) - wrong modality and too late

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Q182. 48-year-old with acute pancreatitis resolving after 8 days. No alcohol, no significant history, normal labs. Which test identifies the cause?

• Hypertriglyceridemia (triglycerides >1000 mg/dL) - third most common cause overall
• Hypercalcemia (hyperparathyroidism) - causes pancreatitis
• Serum cholesterol (A) alone is less specific
• CA 19-9 (C) is a tumor marker, not for diagnosing pancreatitis cause
• Glucose tolerance (D) tests for diabetes (consequence, not cause)

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Q183. 80-year-old with obstructing rectosigmoid carcinoma. Most appropriate treatment?

• Elderly patients
• Unstable/high-risk patients
• Emergency settings

• A. APR with end colostomy - for very low rectal tumors, not rectosigmoid
• B. Subtotal colectomy with ileorectostomy - possible but higher risk in elderly/emergency
• C. Sigmoid colectomy alone - doesn't address obstruction adequately
• E. Anterior resection - elective procedure in prepared bowel, not for emergency obstruction

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Summary Table

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Key Corrections to Marked Answers:

1. Q22 - Marked A is WRONG. Correct is D. Physician-taken BPs are HIGHER (not lower) than nurse-taken due to white coat effect.
2. Q78 - Marked C (SBP) is WRONG. Free air under diaphragm proves visceral perforation - this is bowel wall perforation (B), not SBP. SBP never causes pneumoperitoneum.
3. Q87 - There is confusion in the markings. The UNUSUAL symptom for cecal carcinoma is B - Indigestion, not D. Right colon cancer can cause obstruction (less common than left but possible). Indigestion is an upper GI symptom entirely unrelated to cecal pathology.