USMLE 11-15

Questions 1-6      Questions 7-10   

Q 11)  A 59 year old male alcoholic male presents with history of upper GI bleed of 1 day duration. During the day he has had three episodes of bleeding each time about 150 ml. Blood is fresh and not associated with retching. He has a history of long standing alcohol intake. What will be the most likely cause of GI bleed

a) Mallory weiss tear

b) Esophageal varices

c) Gastric ulcer

d) Esophagitis

11 b

Long standing alcohol intake means some stigma of liver disease leading to chronic liver disease and consequently esophageal varices. 

Mallory Weiss tear occurs with retching and after episodes of binge drinking

Gastric and duodenal ulcers are related to alcohol but usually presents at 40 years 

Esophagitis will have associated symptoms of GERD and long standing history

Q 12 ) 75 year old man complains of obstipation for 2 days. He has taken laxatives but continues to have worsening pain and distension associated with vomiting. He underwent b/l knee replacement  2 weeks back. He was on Inj fentanyl for pain control. He is on antihypertensives and lipid lowering agents for the past 15 years.

On examination  he is afebrile, oriented, pulse rate of 100 min/, BP 120/60 and abdomen is distended with mild tenderness. There are no signs of peritonitis, bowel sounds are sluggish.

TLC is 6,500, and potassium is 3.2 . All other blood tests are normal. X ray abdomen and CT abdomen shows dilated large bowel loops and oral contrast upto splenic flexure.

What is the probable diagnosis

a) Ischemic colitis

b) CMV colitis

c) Colonic Pseudoobstruction

d) Caecal volvulus

12 . c

Colonic pesudoobstruction also known as Ogilvie syndrome

Pointers for this are

  1. Age of the patient
  2. Recent history of surgery, opioid  use
  3. CT scan does not show any evidence of mechanical bowel obstruction
  4. Hypokalemia is associated with it

Predisposing factors-  Non operative trauma, Severe infection,  MI, CHF, Abdominal, orthopedic or pelvic operation. 

Other conditions

  1. Infective colitis - diarrhea with high TLC should be there
  2. CMV- Immunosuppressed, diarrhea
  3. Colonic volvulus - Abrupt cut off on CT
  4. Ischemic colitis - Same age group, more after vascular surgeries, more pain, blood in stools, increased lactate

Q13) A 68 year old man undergoes repair of infra renal aortic aneurysm. On 2nd POD he has abdominal pain, bloody diarrhea and tachycardia. BP is 120/70. Abdomen is mildly distended and tender especially in the left lower quadrant.

How will you proceed

a) Send stool for clostridium and spores

b) CT Abdomen

c) Exploratory laparotomy

d) Higher antibiotics

13. b 

Get a contrast CT Abdomen as bowel ischemia is a likely diagnosis 

Incidence of bowel ischemia after repair of aortic aneurysm is around 2-6%. It is because of loss of inferior mesenteric artery artery at the time of surgery and inadequate colonic collaterals. 

Spores and clostridium difficle diarrhea occurs after prolonged antibiotic use. Also there is no bloody diarrhea in it.

Exploratory laparotomy will be required after CT Shows full thickness gangrene and not before

Antibiotic escalation will not help at this stage.

Q14) A young 18 years old unrestrained car driver has an head on collision with a truck and becomes unconscious. He is intubated on the site of accident and resuscitated with IV fluids. He is brought to the emergency in a state of shock,( BP 90/60 and pulse 120/min) but opens eyes on commands. On examination he does not have  pallor but neck veins are distended.

There are no signs suggestive of head or spine injury. Xray chest reveals normal cardiac chambers, no free gas and mild pleural effusion on left with no evidence of fracture ribs.

What will be the next step of management

a) Resuscitation and simultaneous CT thorax

b) Resuscitation and simultaneous Echo cardiography

c) Exploratory laparotomy

d) Chest tube drainage left side


As Patient continues to have hypotension with distended neck veins, this is could be case of pericardial tamponade. As there is no pallor, the chances of active bleeding are less. Although CT Abdomen will be required at some stage, echocardiography is needed to rule out pericardial tamponade.

Treatment for this condition is pericardiocentesis.

Other probabilities could  include, lung injury with hemothorax, aortic rupture and tension pneumothorax 

Q15. A 38 year old male patient has symptoms suggestive of ulcer disease. Endoscopy shows 3 ulcers in proximal jejunum ranging in size from 0.5 to 1.5 cm. Biopsy is taken which is benign and a course of antibiotics is given for H. Pylori. The ulcers and symptoms are persistent  What should you do next?

a) Repeat Biopsy

b) Change the antibiotic

c) CT abdomen

d) Serum gastrin


Gastric acid studies and serum gastrin

Most common sites for gastric ulcers are stomach and duodenum. If ulcers are found in eccentric position like esophagus and jejunum, there is a strong suspicion of gastrinomas.

Gastrinoma are common in the setting of MEN 1 syndrome and are characterised by high serum gastrin and high gastric acid output.

Other features which are suggestive of gastrinoma are 

a) Size more than 1 cm

b) Not going after adequate treatment of H. Pylori

c) More than 1 ulcers

Diagnosis is two way

1st to confirm the diagnosis

a) Gastrin and Gastric acid output

b) Secretin suppression tests

2nd for localisation 

a) Endoscopic ultrasound is most sensitive