View source for WBR1111

{{WBRQuestion
|QuestionAuthor={{M.P}}
|ExamType=USMLE Step 3
|MainCategory=Emergency Room
|SubCategory=Gastrointestinal
|MainCategory=Emergency Room
|SubCategory=Gastrointestinal
|MainCategory=Emergency Room
|SubCategory=Gastrointestinal
|MainCategory=Emergency Room
|MainCategory=Emergency Room
|SubCategory=Gastrointestinal
|MainCategory=Emergency Room
|SubCategory=Gastrointestinal
|MainCategory=Emergency Room
|SubCategory=Gastrointestinal
|MainCategory=Emergency Room
|SubCategory=Gastrointestinal
|MainCategory=Emergency Room
|MainCategory=Emergency Room
|SubCategory=Gastrointestinal
|Prompt=A 43 year old male is brought to the emergency department with complaints of sudden onset of severe abdominal pain for the past five hours.  The pain is generalized and is increasing in severity since then.  He also had two episodes of non-bloody vomiting on the way to the emergency department.  On further review of his history, he reveals that he was having recurrent episodes of abdominal pain for the past three months, especially after meals that persisted for one to two hours.  He denies any blood or mucus in stools or any recent travel outside the country.  His past history is significant for mitral valvular disease and is on ACE inhibitors and thiazide diuretics for that.  He is a chronic smoker, but consumes alcohol occasionally.  His family history is insignificant.  On examination his vitals are pulse: 114/min, BP: 100/60 mmHg and temperature: 38 degree Celsius.  Abdominal examination reveals generalized tenderness with no rebound tenderness and guarding.  Bowel sounds are normal.  Other system examinations are normal except for a murmur at the mitral area.  What is the most likely diagnosis at this point in this patient?
|Explanation=Intestinal ischemia are a heterogeneous group of diseases characterized by hypoxia of the small bowel and/or colon, which most commonly arises from occlusion, vasospasm, and/or hypoperfusion of the mesenteric vasculature.  Intestinal ischemic disorders have been classified into the three major types namely, acute mesenteric ischemia, chronic mesenteric ischemia and [[colonic ischemia]].  [[Acute mesenteric ischemia]] refers to the sudden onset of intestinal hypoperfusion, most commonly due to acute embolic or thrombotic occlusion of the superior mesenteric artery (SMA).  Nonocclusive mesenteric ischemia, a form of acute mesenteric ischemia that has sub acute presentation results from arterial hypoperfusion due to primary splanchnic vasoconstriction, often associated with a low cardiac output state.  The diagnosis of AMI depends upon a high clinical suspicion, especially in patients who develop severe and persisting [[abdominal pain]] that is disproportionate to their abdominal finding and with known risk factors such as [[atrial fibrillation]], [[congestive heart failure]], [[valvular heart disease]], [[peripheral vascular disease]], or a history of [[hypercoagulability]]. 
|AnswerA=Acute pancreatitis

|AnswerAExp=[[Acute pancreatitis]] should be suspected in patients presenting with severe epigastric abdominal pain (which worsens on eating) radiating to the back associated with risk factors such as heavy [[alcohol]] use, certain medications, family history, history of autoimmune diseases, and history of [[gallstone]] diseases.  This patient’s presentation with cardiovascular risk factors and chronic mesenteric ischemia is most likely to be of acute mesenteric ischemia than pancreatitis. 
|AnswerB=Acute mesenteric ischemia

|AnswerBExp=This  patient most likely has acute mesenteric ischemia at this point as he developed severe and persisting abdominal pain that is disproportionate to their abdominal finding and has known risk factors of acute mesenteric ischemia such [[valvular heart disease]] and chronic mesenteric ischemia.
|AnswerC=Chronic mesenteric ischemia

|AnswerCExp=Chronic mesenteric ischemia also called as [[intestinal angina]], is manifested by recurrent acute episodes of abdominal pain, resulting from insufficient splanchnic blood flow during periods of heightened intestinal demand along with risk factors of underlying atherosclerotic vascular disease such as peripheral vascular disease or [[coronary artery disease]].  The severity of the pain is increased after larger meals and usually subsides over the course of the next two hours.  Though this patient has chronic mesenteric ischemia for 3 months, at this point he has a presentation of acute mesenteric ischemia. 
|AnswerD=Colonic ischemia
|AnswerDExp=Colonic ischemia, the most frequent form of intestinal ischemia, affects mostly the elderly patients with known risk factors for mesenteric ischemia such as aortoiliac instrumentation/surgery, [[cardiopulmonary bypass]], [[myocardial infarction]], acquired or hereditary [[thrombophilia]], certain drugs and extreme [[exercise]].  It usually presents with mild abdominal pain and tenderness over the affected bowel, associated with mild to moderate amounts of [[rectal bleeding]] or bloody [[diarrhea]] within 24 hours of the onset of abdominal pain.  This patient’s presentation with cardiovascular risk factors and chronic mesenteric ischemia is most likely to be of acute mesenteric ischemia than colonic ischemia. 
|AnswerE=Perforated peptic ulcer disease

|AnswerEExp=[[Peptic ulcer disease]] includes gastric and duodenal ulcers.  A [[gastric ulcer]] would give epigastric pain during the meal, as gastric acid is secreted, or after the meal, as the alkaline duodenal contents reflux into the stomach.  Symptoms of duodenal ulcers would manifest mostly before the meal,  when acid (production stimulated by hunger) is passed into the duodenum. The risk factors for PUD includes episode of H. pylori infection, chronic use of [[NSAIDs]], cigarettes/alcohol intake and family history of peptic ulcer.  This patient’s presentation with cardiovascular risk factors and chronic mesenteric ischemia is most likely to be of acute mesenteric ischemia than peptic ulcer disease.
|RightAnswer=B
|WBRKeyword=Intestinal ischemia, [[acute mesenteric ischemia]], [[mesenteric ischemia]], [[colonic ischemia]]
|Approved=Yes
}}