Depopulation of interstitial cells of cajal in chagasic megacolon: towards tailored surgery?

Abstract

BACKGROUND: The mechanism of constipation in patients with Chagasic megacolon remains partially explained. In these patients, it was recently demonstrated a reduction in the population of interstitial cells of Cajal. AIM: To evaluate density of Cajal cells in the surgically resected colon of Chagasic patients in comparison to control patients, and to verify possible association between preoperative and postoperative bowel function of Chagasic patients and colonic cell count. METHOD: Sixteen patients with Chagasic megacolon were operated on. Clinical pre- and post-operative evaluation using the Cleveland Clinic Constipation Score was undertaken. Resected colons were examined. Cajal cells were identified by immunohistochemistry using anti-CD117 antibody. The mean cell number was compared to resected colons from 16 patients with non-obstructive sigmoid cancer. Association between pre-and post-operative constipation scores and cell count for megacolon patients was evaluated using the Pearson coefficient correlation test (r). RESULTS: A reduced number of Cajal cells [cells per field: 2.84 (0-6.6) vs. 9.68 (4.3-13) - p<0.001] was observed in the resected colon of Chagasic patients when compared to colon cancer patients. No correlation between constipation score before (r=-0.205; p=0.45) or after surgery (r=0,291; p=0.28) and cell count for megacolon patients was observed. CONCLUSIONS: Patients with Chagasic megacolon display marked reduction of interstitial cells of Cajal when compared to non-Chagasic patients. An association of constipation severity and Cajal cells depopulation in Chagasic megacolon could not be demonstrated.