Localized bowel distension in the newborn: a review of the plain film analysis and differential diagnosis.

Neonatal abdominal plain films were prospectively analyzed over a 41-month period in order to generate a differential diagnosis for focal bowel distension during the first 6 weeks of life. A total of 31 examples of locally distended bowel were collected. The study discredits the concept that asymmetrically distended bowel in the newborn is usually caused by necrotizing enterocolitis (only 9/31 cases) and indicates that distended bowel in the lower abdomen or left upper quadrant is often caused by air trapping in normal but redundant rectosigmoid (11 cases) or in distal transverse colon (three cases). Five other pathologic conditions not normally specified in differential diagnoses of focally distended bowel included inguinal hernia (three cases), small bowel atresia (two cases), midgut volvulus (one case), Hirschsprung's disease (one case), and small left colon (one case). The study emphasizes the value of sequential supine and prone filming for distinguishing normal from pathologic dilated loops of bowel.