Diagnosis and surgical treatment of isolated hypoganglionosis.

Background: Some patients suspected with Hirschsprung's disease (HD), however, were diagnosed as having isolated hypoganglionosis according to the updated pathohistologic methods. This study was undertaken to investigate the diagnostic methods and the therapeutic results of isolated hypoganglionosis in children.

Methods: A retrospective analysis was made on 17 patients with isolated hypoganglionosis (hypoganglionosis group) identified pathologically after operation. The data included clinical presentations, barium enema, anorectal manometry, histochemical staining for acetylcholinesterase (AChE) before operation, histological results after operation and follow-up outcomes. The data of hypoganglionosis with HD (HD group) were compared retrospectively.

Results: Common complaint of the patients with hypoganglionosis and HD was intractable constipation. Barium enema showed typical narrowing and distended segment of the colon in 9 patients in the hypoganglionosis group (9/16) and in 15 patients in the HD group (15/18). In the hypoganglionosis group, in 15 patients who underwent anorectal manometry only 5 showed absent rectal anal inhibitory reflex, significantly lower than the rate in the HD group (17/18) (P<0.05). From 16 patients in hypoganglionosis group, positive staining for AChE was noted in 3 patients (3/16, 18.8%), significantly lower than that in the HD group (16/18, 88.9%) (P<0.05). Thirteen patients in the hypoganglionosis group received subtotal colectomy, while only 5 patients needed subtotal colectomy in the HD group. In the hypoganglionosis group, except 2 patients who suffered from mild enterocolitis after operation and recovered after conservative therapy, all patients recovered uneventfully without wound dehiscence, intestinal fistula, fecal incontinence or constipation recurrence. In the HD group, one patient suffered from anastomotic leak and got secondary operation, one patient had anastomotic stricture at 1 year after operation and recovered by dilatation, and other three patients suffered from mild enterocolitis after operation and recovered after conservative therapy.

Conclusions: Hypoganglionosis is a common disease, and could be finally confirmed by full-thickness biopsies in different bowel segments. The resection range can be estimated according to barium enema and 24-hour delayed X-ray findings, by which the satisfactory result in short-term follow-up can be obtained.