Microdiverticulitis: a rare but distinct cause of small bowel obstruction in early infancy.
During a 20-year period, eight term infants admitted to a large children's hospital for treatment of dehydration associated with diarrhea (6) and vomiting (2), and who ranged in age from 10 to 60 days at onset of symptoms and 18 to 75 days at presentation, developed distal small bowel obstruction following apparently successful rehydration. With the exception of a single infant who was dead on arrival, and another whose obstruction went unrecognized, all infants came to operation shortly after obstruction was confirmed. In each case, a severely inflamed area of distal ileum (7) or proximal colon (1) was found at autopsy (2) or operation (6) to be the cause; perforation was present in four of the cases. Resection of the diseased segments of intestine, and primary anastomosis, were performed in all six operated cases; reoperation was required in four of the six for leaks (3) and adhesions (1). All but two survived. Pathologically, the resected intestinal segments showed a unique pattern of injury: numerous punctate ulcers were apparent, which undermined the muscularis mucosae, without evidence of necrosis. Regenerating epithelium extended through these defects, resulting in the presence of glandular invaginations, which were surrounded by a brisk inflammatory response: hence the term "microdiverticulitis." We believe this lesion represents a beginning or furtive attempt at repair of severely inflamed, but viable intestine, and that it is a rare but true cause of small bowel obstruction in early infancy, separate and distinct from necrotizing enterocolitis.