[Chronic Megacolon in Young Patients: Epidemiological, Clinical, and Manometric Characteristics]

. Chronic megacolon manifests clinically as a motility disorder. In the vast majority of cases it causes constipation that is hard to treat. Based on its etiology, it can be congenital, acquired or idiopathic.

. To describe the epidemiological, clinical and manometric characteristics in a population under 40 years old with chronic megacolon and chronic constipation.

. Descriptive cross-sectional study. 23 patients treated at Hospital de Gastroenterología Dr. Bonorino Udaondo from March 2019 to March 2021 were enrolled in the study. The diagnosis of chronic megacolon was made by barium enema, and the diagnosis of chronic constipation was based on Rome IV criteria. Epidemiological and clinical data were collected. Anorectal functional outcomes were obtained by conventional manometry. In all cases, medical treatment for constipation was indicated.

. Thirteen female patients, median age: 21 (19-30); age at diagnosis: 16 (13-19). 7 patients (30.4%) had surgery. Causes: 14/23 idiopathic (60.9%), 6/23 probable Hirschsprung disease (2 patients with diagnosis confirmed by biopsy) (26.1%), and 3/23 secondary (13%). Extent: 6/21 megasigmoid (28.6%), 5/21 megarectum (23.8%), and 10/21 generalized (47.6%). Manometric data allowed to identify a prevalence of pelvic floor dyssynergia (14/22 patients; 64%), and rectal hyposensitivity (13/22 patients; 59%). Five patients (21.7%) showed no rectoanal inhibitory reflex. Complications: volvulus, 7/23 patients (30.4%), and fecaloma, 12/23 patients (52.2%). Treatment: 14/23 polyethylene glycol (66.7%), 5/23 linaclotide (23.8%), 13/23 prucalopride (61.9%), 7/23 Murphy drips (31.8%), and 18/23 combined treatments (81.8%). The risk of fecaloma was higher in patients with megarectum than in patients with megacolon (5/5 vs. 3/10) respectively [p < 0.03]). Hyposensitivity and dyssynergia were not associated with risk of fecaloma (p=NS). At the time of this study, only one patient will undergo surgery because she is not responding to medical treatment.

. All patients showed at least one abnormal result in the manometry. More than half of the patients showed at least one fecaloma. Medical treatment in young patients would be effective.