IMMUNOHISTOCHEMICAL EVALUATIONS OF ULTRASHORT-SEGMENT HIRSCHSPRUNGS-DISEASE - REPORT OF 3 CASES

PURPOSE: Unlike classic Hirschsprung's disease, short-segment and ultr ashort-segment varieties are usually found to be latent and milder. Ul trashort-segment Hirschsprung's disease may present as intractable chr onic constipation in children over one year of age, adolescents, and a dults. Anorectal myectomy has been shown in many instances to provide effective long-term treatment for certain patients with ultrashort-seg ment Hirschsprung's disease. Histologically, the affected segment in H irschsprung's disease has been shown to have increased cholinergic ner ves, lack of nitric oxide synthase-containing neuronal elements, and s how moderate to severe loss of myenteric neurons. METHODS: Here, we re port three cases that showed clinical and manometric evidence of ultra short-segment Hirschsprung's disease. Two of the three patients respon ded well to myectomy. RESULTS: Detailed histologic and immunohistochem ical evaluation of the internal anal sphincter and a comparison with t hree normal controls revealed absence of nitric oxide synthase-contain ing neurons in both cases that responded well to surgery and continued presence of these neurons in the patient who did not respond. A revie w of the current literature on various treatment modalities is include d, CONCLUSIONS: Anorectal myectomy provides long-term relief of this c hronic problem in a subgroup of patients with ultrashort-segment Hirsc hsprung's disease who lack nitrinergic neurons at the internal anal sp hincter.