Background and aim: Constipation may be present in ulcerative proctitis (UP), but its pathogenesis has not yet been evaluated. The aim of this article is to investigate functional and morphologic features of the anorectal region in patients with UP and constipation.
Materials and methods: Eleven patients with quiescent clinical, endoscopic, and histological UP and constipation and 10 patients with functional constipation (FC) underwent radiologic evaluation of intestinal transit time, anorectal manometry, and defecography. Transit time was measured with radiograms at 72 h after ingestion of radiopaque markers. Manometry was carried out using a continuous perfused catheter and a balloon inflated with increasing volumes of air. Defecography was performed after the injection of a barium-sulfate solution in the rectum, with the registration of videotapes during straining, squeezing, and evacuation.
Results: Manometry showed in UP significantly lower values of rectal compliance than those in FC (3.10 and 5 mL/mmHg, respectively) (P = 0.03). Rectal sensitivity threshold was increased but without significant differences in UP and FC (30 and 50 mL air, respectively). At defecography, the median value of rectosacral space was increased in UP in comparison with FC (1.30 vs 0.8; P = 0.002). Lateral rectal diameter in UP was lower than in FC (6 and 8.8 cm, respectively; P = 0.016). Nonsymptomatic rectocele, mucosal prolapse, descending perineum, and abdominopelvic dyssynergy were equally present in UP and FC. The majority of UP patients showed a prolonged intestinal transit time similar to FC patients, and, more frequently, they showed low transit in the left colon in comparison with the right colon in comparison with FC patients.
Conclusions: This study suggests that constipation in UP may be correlated with rectal fibrosis, which reduces the transit of stools from the left colon. The concomitance of asymptomatic anorectal organic or functional alteration may contribute to worsen constipation.