Identification of the Different Subtypes of Dyssynergic Defecation: A Descriptive Study in a Tertiary Care Hospital

Abstract

Introduction. Dyssynergic defecation is a functional disorder characterized by a lack of coordination between abdominal contractions and the relaxation of the anal sphincter, leading to chronic constipation. The main symptoms include a sensation of incomplete evacuation and excessive defecatory effort. Diagnosis requires excluding organic causes and evaluating alarm symptoms through digital rectal examination, high-resolution anorectal manometry, and balloon expulsion tests. Dyssynergic defecation is classified into four subtypes based on the manometric mechanisms involved.

Objective. To describe the clinical and manometric characteristics of patients suspected of having dyssynergic defecation and estimate the proportions of the different subtypes.

Materials and methods. Observational, descriptive, and retrospective study of 170 patients over 18 years of age diagnosed with dyssynergic defecation, evaluated at Hospital de Clínicas José de San Martín. High-resolution anorectal manometry was performed with a 12-circumferentially-oriented pressure sensors catheter and a balloon expulsion test. Manometric patterns were classified into four subtypes based on defecatory effort and sphincter relaxation.

Results. The average age was 59.3 years (SD 15.7), and 80.6% of the patients were women. The distribution of the subtypes was as follows: type I (31.2%), type II (17%), type III (22.9%), and type IV (28.8%). No significant differences were found in age distribution (p = 0.558). Type IV dyssynergia had the highest proportion of women (95.9%, p = 0.015). The presence of symptoms such as incomplete evacuation, defecatory effort, and digitations varied between subtypes, but no statistically significant differences were found.

Conclusion. The study confirms the clinical and manometric heterogeneity of patients with dyssynergic defecation. While some subtypes show a higher association with certain symptoms, the lack of significant differences suggests that other factors might influence the clinical presentation. High-resolution anorectal manometry remains key in the evaluation and classification of dyssynergic defecation.