Although Crohn's disease frequently affects the perianal region and its function, studies evaluating anorectal function in these patients are rare and with controversial results. The impact of perianal disease on anorectal function complaints is not clear, other factors such as disease activity, stool consistency and decreased rectal capacity may have a more important role in its pathogenesis. Athanasios et al. found no association between the values of resting and squeeze pressure and fecal incontinence in Crohn's disease (CD) patients. According to the authors, this result could be explained by the difference in the pathophysiology of fecal incontinence among patients with inflammatory bowel disease (IBD). The aim of this study is to determine associated manometric factors, the role of perianal disease, disease activity and fecal consistency in anorectal dysfunction in CD patients.
This is an observational, cross-sectional study. Fifty-six Crohn's disease patient under outpatient follow-up, completed a questionnaire and were submitted to a medical record review, and anorectal manometry. Manometric variables studied: resting and squeeze pressure, anismus, rectoanal inhibitory reflex (RAIR), rectal sensitivity and capacity and proof of balloon expulsion. Functional disorders studied: fecal incontinence and urgency, incomplete/obstructed evacuation and tenesmus.
Software R for Windows, version 4.0.2 was used for the statistical analyses. Pearson's χ2 test, Fisher's exact test and T-Student Test for independence was used to study the association between manometric and clinical variables and functional disorders, with P < 0,05.
Of the 56 patients evaluated, 53.6% are male, with a mean age of 41.4 years (SD: 12.4). According to the Montreal Classification, most patients have non-penetrating/non-stenosing disease (61.5%). Perianal disease, was present in 44.2% of the patients. Most patients were in remission, according to the Harvey-Bradshaw Index. Among the functional complaints, the most common is fecal incontinence (38%), followed by a sensation of obstructed/incomplete evacuation (36%) and fecal urgency (29%). When patients with anorectal functional complaints (fecal incontinence, incomplete/obstructed evacuation, fecal urgency and tenesmus) were compared with patients without anorectal functional complaints, no statistically significant difference was found in relation to perianal disease.
On the other hand, a statistically significant difference was found when we compared the patients with any anorectal functional complaint (fecal incontinence, incomplete/obstructed evacuation, fecal urgency and tenesmus) with the patient without any complaints in relation to activity index of the disease and fecal consistency.
Our results suggest that functional complaints in patients with Crohn's disease are more related to disease activity and fecal consistency, among other factors, than structural and functional ano-rectal-perineal abnormality, including those caused by perianal involvement of the disease. Therefore, the control of the disease activity probably is critical for the management of this function symptoms.