rectal biopsy for diagnosis of hirschsprung disease in constipated children

background: constipation is a common problem in children and most of them are idiopathic or functional. only a few percent of constipations may relate to hirschsprung disease (hd) and may need to rectal biopsy for diagnosis. now a day, most of these children referred to the pediatric surgeon for rectal biopsy to rule out of hd. with regard to complication, emotional effect, spending time and the cost and other side effects of sugary procedure, it seems logical and essential to determine restrict criteria for surgical performance. that's why we performed this study. methods: 100 cases of children rectal biopsies (43 girl and 57 boys) have been recorded during 2006-2008 in kermanshah imam reza hospital included in this descriptive-analytic study. known constipation etiologies such as hypothyroidism, anal stenoses were excluded from the study. results: study showed that only 15 percent of subjects were diagnosed for hirschsprung. disease has been started before 6 months of age in the most of cases and all of them showed one or more major symptoms of hd. in 85% of samples pathology reports were normal who were diagnosed idiopathic constipation and all of them after 6 months of age and none had major symptom of hd. conclusion: we concluded that rectal biopsy is not necessary in children whose constipation disease has been started after 6 months of age and did not indicate a cardinal sign of hirschsprung.