Histologic criteria for the diagnosis of allied diseases of Hirschsprung's disease in adults.

A few reports in the literature have discussed the histologic criteria for the diagnosis of allied diseases of Hirschsprung's disease in adults, and studies report that intestinal neuronal dysplasia (IND) in adults may develop from IND in infants. The aim of this study was to examine the differences between the histological findings of IND in infants and those in adults, and to assess whether allied diseases of Hirschsprung's disease (HD) in adults should be considered as congenital or acquired diseases. For these purposes, we studied nine adult patients with severe constipation, and an adult patient with acute intestinal obstruction. We routinely examined the patients using barium enema, anorectal manometry and rectal mucosal biopsy. However, in patients suspected of allied diseases, we carried out full-thickness rectal biopsies. In seven operated cases, we also examined resected intestines. The tissue samples were examined using AChE-staining, NADPH-diaphorase staining, HE-staining, and silver impregnation. Histologically, we diagnosed two males as having HD, two males as having IND, five patients (two males and three females) as having hypoganglionosis, and one female as having a degeneration of the intramural plexus. The following conclusions were drawn: 1) Inflammations such as ulcerative colitis or ischemic colitis may cause IND TYPE B in adults whose histological findings are similar to those generally seen in infants; 2) It is suggested that IND is closely related to hypoganglionosis; 3) In hypoganglionosis, a patient with findings of elevated AChE-positive nerve fibers in the mucosa and AChE-positive nerve fibers in an arterial wall may belong to a subtype of IND; 4) Most of the allied diseases of HD in adults may occur as an acquired disease, not as a congenital disease.