Clinical and manometric investigation in constipated Chagasic patients with and without megacolon

Abstract

Background Chagasic colopathy is the second most common digestive manifestation, and constipation is the main symptom. The absence of the Rectoanal Inhibitory Reflex plays an important role in constipation and anal manometry is crucial for appropriate evaluation. Purpose Evaluate anal manometry findings (mainly Rectoanal Inhibitory Reflex) in Chagasic patients with chronic constipation, with and without megacolon and correlate these findings with clinical and demographic data. Methods Cross-sectional study of patients with chronic constipation who underwent Chagasic serologic test, barium enema, and anal manometry. The absence of Rectoanal Inhibitory Reflex was evaluated using the mid-P Exact Test. Results 64 Patients were included: 23 Chagasic patients with megacolon/megarectum (G1), 21 Chagasic patients without megacolon/megarectum (G2) and 20 non-Chagasic patients without megacolon/megarectum (G3). Chagasic patients with megacolon had a higher incidence of fecaloma (39%) compared to the other two groups (9.5% and 10% for G2 and G3, respectively, p = 0.03). Rectal capacity on manometry was statically higher for G1 patients. Rectoanal Inhibitory Reflex was absent in 91.3% of patients in G1, 47.29% in G2 and present in all patients in G3. There was a significant difference in the absence of the Rectoanal Inhibitory Reflex when comparing the groups (G1 vs. G2: p = 0.002, G1 vs. G3: p < 0.001, G2 vs. G3: p < 0.001). Conclusion The absence of RAIR confirms the diagnosis of Chagasic colopathy and endorses surgical treatment whenever clinical treatment fails. The presence of the RAIR in patients with positive serology for Chagas disease without megacolon/megarectum might not be due chagasic colopathy and other causes should be considered.