ACETYLCHOLINESTERASE (ACE) STAINING SHOWS THE ABNORMAL INNERVATION OFA PULLED-THROUGH RECTUM IN A CASE OF REPAIRED ANORECTAL MALFORMATION

Abnormal innervation of the anorectum was noted in relation to anal in continence in a case of repaired high-type anorectal malformation (ARM ). A ten-year-old boy presented with anal incontinence after reconstru ctive surgery of ARM with a recto-urethral fistula. An anorectal manom etrical examination revealed both an adequate tonus of the anal sphinc ter muscles and the absence of rectoanal reflex relaxation. And a bari um enema showed a narrow region in the rectosigmoid colon, which was s imilar to that of Hirschsprung's disease (HD). Furthermore, an acetylc holinesterase (ACE) histochemical study of the rectal suction biopsies revealed an increased number of ACE-positive nerve fibers in the lami na propria mucosae and muscularis mucosae of the pulled-through colon. At the same time, however, some ganglia cells were also observed in t he submucosa of the affected rectosigmoid colon and these cells could not be found in HD. Although the mechanism by which the abnormally inn ervated parasympathetic nerve fibers arose in the pulled-through colon remains unclear, this neuronal abnormality is considered to be the ca use of anal incontinence in this case.