Brown bowel syndrome: report of two cases.

Brown bowel syndrome is a rare intestinal disorder associated with the deposition of lipofuscin pigment in the smooth muscle cells. We report two such cases presenting with intestinal pseudo-obstruction, abdominal pain, and body weight loss. Both cases had malabsorption and fatty liver. Exploratory laparotomy revealed brownish discoloration of the small bowel wall and enlargement of mesenteric lymph nodes. Light microscopy, autofluorescence and ultrastructure studies confirmed the deposition of lipofuscin pigments in the intestinal muscle cells and reticuloendothelial cells of mesenteric lymph nodes. In addition, the calf muscle biopsy of case 1 displayed myopathy and fatty replacement. Skeletal muscle strength of both patients was partially restored after parenteral and oral vitamin E supplement and other conservative treatment, but gastrointestinal symptoms of both patients continued to deteriorate. Thus, brown bowel syndrome associated with prolonged and severe malnutrition and possibly vitamin E deficiency appears only partially responsive to vitamin E supplementation.