A 7-day old infant presents with bilious vomiting and gross abdominal distention with absent bowel sounds. X ray abdomen shows multiple gas filled loops. Diagnosis is?
First, bilious vomiting in neonates is a red flag. It usually suggests a surgical emergency. Common causes might include intestinal obstruction. The age is 7 days, so I should think about conditions that present in the neonatal period.
Bilious vomiting with abdominal distention and absent bowel sounds points towards a mechanical obstruction. The X-ray showing multiple gas-filled loops could indicate a blockage preventing normal passage of contents. In neonates, common causes include intestinal atresia, malrotation with volvulus, or Hirschsprung's disease.
Intestinal atresia is a congenital condition where there's a complete blockage of the intestine. It often presents with bilious vomiting and abdominal distention. The X-ray would show dilated loops of bowel. Malrotation with volvulus can also cause similar symptoms, especially if there's a volvulus leading to obstruction and possible ischemia. However, Hirschsprung's disease typically presents with chronic constipation and failure to pass meconium, which might not fit here.
Given the acute presentation and the X-ray findings, intestinal atresia is a strong possibility. The absence of bowel sounds might indicate paralytic ileus, but in this context, it's more likely due to obstruction. The other options like malrotation could also be considered, but the age and presentation are more classic for atresia.
So the correct answer is probably intestinal atresia. Let me check the options again. If the options include intestinal atresia, that's the one. The other options would be malrotation, Hirschsprung's, or maybe something else. But based on the info given, intestinal atresia fits best.
**Core Concept**
This question tests recognition of neonatal intestinal obstruction causes. Bilious vomiting in neonates (<30 days) with abdominal distension and gas-filled loops on X-ray suggests **midgut volvulus** or **intestinal atresia** as leading diagnoses. Both are surgical emergencies requiring urgent intervention.
**Why the Correct Answer is Right**
The classic triad of bilious vomiting, abdominal distension, and absent bowel sounds in a neonate strongly suggests **midgut volvulus** due to malrotation. Malrotation with volvulus occurs when the midgut twists around the mesentery, causing obstruction and compromising blood supply. The X-ray findings of "multiple gas-filled loops" (string of sausages) and a "corkscrew" appearance of the terminal ileum support this. Early diagnosis is critical to prevent bowel ischemia/necrosis.
**Why Each Wrong Option is Incorrect**
**Option A:** *Intestinal atresia* typically presents in the first 24–48 hours with non-bilious vomiting and "double bubble" sign on X-ray (air in stomach and proximal duodenum), not multiple gas-filled loops.
**Option B:** *Hirschsprung’s disease* causes chronic constipation, failure to pass meconium, and a "telescoped" rectum on X-ray, not acute bilious vomiting.