A 7-year study of the diagnostic value of rectal mucosal acetylcholinesterase measurement in Hirschsprung's disease.

Over a 7-year period, 213 children were investigated for failure to pass meconium or for chronic constipation. Of these, 45 were confirmed to have Hirschsprung's disease; in this group the acetylcholinesterase activity in rectal biopsy tissue was significantly increased (P less than .001; mean 34.2, 95% confidence limits, 8.6 to 95.2) units g-1 when compared with the non-Hirschsprung's group (mean 6.6, 95% confidence limits, 2.0 to 15.9 units g-1). By expressing the acetylcholinesterase activity as a percentage of the total cholinesterase activity it is possible to compensate for evaporative weight loss and the combination of these two measurements improves the overall diagnostic value of the test. There were no false-positive and only two false-negative results.