A rapid technique of acetylcholinesterase staining.

When tissue samples are evaluated for the presence of Hirschsprung's disease, results of acetylcholinesterase staining are usually more informative than findings from the routine hematoxylin-eosin method. The standard technique for staining acetylcholinesterase takes 2 hours to perform and is based on the enzyme histochemical method of Karnovsky and Roots, with a subsequent visualization step as described by Hanker and colleagues. We modified the technique by the introduction of supplemental oxidation, which accelerated the staining time to less than 10 minutes. When evaluated in 10 patients with Hirschsprung's disease and in seven control patients with normal colons, the rapid technique gave identical staining of nerves and ganglion cells to that of the standard method. Increased visualization of endogenous peroxidase-containing histiocytes occurred, but it was not a diagnostic problem. The technique is sufficiently rapid to be used in conjunction with routine frozen sections to assist in the diagnosis and in selecting the optimal level of resection at the time of definitive surgery.