Meconium ileus is a type of neonatal intestinal obstruction that occurs when abnormally thick meconium impacts in the ileum causing blockage of intestinal flow. Most infants with meconium ileus have cystic fibrosis, a congenital condition characterized by abnormally thick intestinal secretions and pancreatic insufficiency. The pathogenesis of meconium ileus is due to hyperviscous mucus secreted by abnormal intestinal glands, abnormal concentrating processes in the proximal small intestine, and pancreatic enzyme insufficiency. The clinical presentation of meconium ileus is that of abdominal distention, bilious vomiting, and failure to pass meconium. Cases of meconium ileus are usually evaluated with plain abdominal radiograph and contrast enema. Numerous air-filled loops of bowel on the supine view with characteristic absence of air-fluid levels are commonly seen on the radiograph, but the presence of calcification suggests intestinal perforation. Contrast enema examination is useful in cases with microcolon. Uncomplicated meconium ileus obstruction can be relieved by giving one or more dilute diatrizoate sodium enema (with Nacetylcysteine added) under fluoroscopy. Surgery is indicated when there is progressive distention or signs of clinical deterioration despite multiple enemas, as well as in complicated cases like meconium peritonitis, ileal atresia or stenosis, ileal perforation, and volvulus with or without pseudocyst formation.
Part of the book: Pediatric Surgery, Flowcharts and Clinical Algorithms