Neisseria meningitidis plated on blood agar

Question.

A 67 year old retired taxi driver with a history of a previous myocardial infarction presents to the emergency department with severe abdominal pain. He complained of bloody diarrhea earlier in the day. On examination he is found to have severe generalized abdominal tenderness. His bloods shows a WCC of 20 × 109 cells/l and a lactate of 5 mmol/L. A triple phase CT shows bowel ischemia from the splenic flexure to the proximal part of the rectum. Which vessel is likely to be compromised?

    1. Superior mesenteric artery
    2. Inferior mesenteric artery
    3. Left colic artery
    4. Coeliac axis
    5. Middle colic artery

Answer.

2. 

 
Explanation.

The inferior mesenteric artery supplies the large bowel from the splenic flexure to the superior part of the rectum. The superior mesenteric artery supplies the lower part of the duodenum to the middle third of the transverse colon. The coeliac axis supplies many structures and this includes the proximal half of the duodenum. The middle colic and left colic artery are branches of the superior mesenteric artery and inferior mesenteric artery respectively.