Idiopathic megarectum in children

Abstract

There is scant information about the management of idiopathic megarectum in childhood. Children with idiopathic megarectum referred to a single institution between 1994 and 1998 were identified prospectively. Those with Hirschsprung's disease or an anorectal malformation were excluded. The remaining patient group, 22 boys and 7 girls, had a median age of 8.0 years (range 3.5-14.0 y). Median duration of symptoms prior to referral was 2.0 years (range 0.4-11 y). Chronic soiling was the dominant complaint in 28/29 (97%) cases. 23 children had received regular stimulant laxatives for periods ranging from 1 month to 11 years, and 9 children had been treated with regular enemas. The degree of megarectum assessed by both abdominal palpation and plain radiography was: grade 1 (below umbilical level) n=6; grade 2 (at umbilical level) n=15; and grade 3 (above umbilical level) n=8. Hirschsprung's disease was specifically excluded by rectal biopsy in all cases and no patient had evidence of spinal dysraphism. Three boys with massive megarectums and intractable symptoms were treated by a staged Duhamel sigmoid pull-through with excellent functional results. Fifteen patients (52%) were treated by a single manual evacuation under general anaesthesia followed by a daily Bisacodyl 5-10 mg suppository. After a median follow-up of 16 months, 13 continue to respond well with a daily bowel action and no soiling (4 of the 13 have discontinued treatment and remain well). The remaining 11 patients (38%) have continued conventional treatment with oral laxatives but with limited success. Idiopathic megarectum is poorly described in children. It is more common in boys and is often resistant to laxative therapy alone. After appropriate preparation, treatment with stimulant suppositories can be effective. Surgery has a valuable role in selected patients with a massive megarectum.