PURPOSE: Mowat-Wilson syndrome (MWS) is a developmental disorder presenting with 
mental retardation, delayed motor development, and a wide spectrum of clinical 
features. Hirschsprung's disease (HD) is associated in almost 50% of cases. This 
report aims to analyze the course of HD and to evaluate the clinical outcomes of 
these patients.
PATIENTS AND METHODS: Between 1997 and 2007, 110 patients presenting with HD 
were diagnosed and managed in our institution. Five of them presented the 
association of HD and MWS. Their records were reviewed retrospectively.
RESULTS: All of the 5 patients have a genetic disorder specific of MWS (nonsense 
mutation or deletion on SIP1 gene, locus 2q22). Two patients underwent transanal 
endorectal pull-through procedure for classic rectosigmoid HD. Three patients 
were operated on for total colonic aganglionosis using Duhamel procedure. The 
median follow-up was 4 (range, 0.3-7) years. Only one patient is doing well 
(rectosigmoid HD). Two patients have a stoma diversion for severe motility 
disorders. Of the 3 total colonic aganglionosis, one still has repeated episodes 
of obstruction requiring total parenteral nutrition (TPN). The 2 others still 
have repeated episodes of enterocolitis. All patients required a prolonged TPN 
(32.5 months in average).
CONCLUSION: Hirschsprung's disease associated with MWS is a severe condition. 
Even in case of short segment HD, patients can present motility disorder 
requiring a prolonged TPN. Physician and surgeon should be aware about the 
evolution of this rare condition.