Question: Human Development
At a postnatal check-up, a 6-week-old girl weighs less than her birth weight. Her mother reports that she vomits and regurgitates bile-stained fluid after every feeding. An upper gastrointestinal contrast study shows the duodenojejunal junction located to the right of the midline and a corkscrew appearance of the proximal small bowel. Which of the following is the most likely diagnosis?
Choose one answer.
Explanation
Correct answer: B. Intestinal malrotation with midgut volvulus
Bile-stained vomiting in an infant signals obstruction distal to the ampulla of Vater and is an emergency. A duodenojejunal junction displaced to the right of midline with a corkscrew configuration of the proximal small bowel indicates intestinal malrotation with midgut volvulus, in which the malpositioned bowel twists around the superior mesenteric vessels. Pyloric stenosis causes nonbilious vomiting because the obstruction is proximal to the ampulla.
Learning objective: Recognize malrotation with midgut volvulus from bilious vomiting and the corkscrew sign.
Want this back right before you'd forget it?
Ebb Deck brings back 1,500 USMLE Step 1 questions like this one with spaced repetition, on the web and on iPhone. Your first 100 are free.