Degenerative leiomyopathy in children. A clinico-pathological study

The syndrome of degenerative leiomyopathy (DL) causing intestinal obstruction clinically manifests in young indigenous African children as massive megacolon without aganglionosis. We report on a clinico-pathologic study of 18 children seen over a 15-year period. All patients came from the same geographic area. Mean age at presentation was 9.5 years with mean duration of symptoms 4.3 years. The youngest infant was 6 months old. Eighteen children presented with progressive abdominal distention and infrequent stooling; 11 had intermittent diarrhoea and 9 colicky abdominal pain. Gross colonic gaseous distention was noted with proximal extension into the small bowel in 9 and into the stomach and oesophagus in 4. The rectosphincteric reflex was present in all 7 patients studied with anorectal manometry. The diagnosis, confirmed on full-thickness rectal biopsy, showed characteristic features distinguishing it from chronic idiopathic intestinal pseudo-obstruction, progressive systemic sclerosis, and mixed connective-tissue disease of childhood. The bowel was dilated, thin-walled, and on microscopy showed smooth-muscle degeneration and necrosis with replacement fibrosis of muscular layers, displacement of ganglion cells, mild increase in numbers and thickness of nerve fibres, mild inflammatory change, and medial fibrosis of small muscular arteries. Immunohistochemical studies were within normal limits. One child died; 14 have been maintained with a combination of prokinetic agents, low-residue diet, laxatives, and enemas; and 3 patients did not respond to this medical therapy on short-term follow-up. Nine children required surgical intervention — 2 diagnostic laparotomies, 4 volvulus, and 3 adhesive bowel obstructions. Four of these required subsequent surgical procedures. DL is a distinctive entity with a classical clinical and histologic picture whose exact etiology is still obscure, Exploratory laparotomy should be avoided.