The relationship between etiology, symptom severity and indications of surgery in cases of anal incontinence: a 25-year analysis of 1,046 patients at a tertiary coloproctology practice.

Background: The etiology of anal incontinence (AI) is often multifactorial. There is little data on the relationship between the etiology of AI, symptom severity, and the need for surgery. The aim of our study was to investigate this association in a large number of unselected patients with AI referred to a tertiary specialist coloproctological practice.

Methods: Patients with AI seen at our unit between 1983 and 2008 were analyzed. The main etiologies were categorized as congenital, traumatic, neurologic, idiopathic, post-operative, post-obstetric, secondary to rectal prolapse, or inflammatory bowel disease. The severity of AI was graded using the validated Pescatori incontinence scale.

Results: Overall, 1,046 patients were studied. The AI score was higher in patients with congenital (4.7 ± 1.1), traumatic (4.6 ± 1.4), and neurological (4.4 ± 1.2) incontinence. Surgical treatment was indicated in 214 cases (20.5%). Patients with AI related to trauma and congenital anomalies required surgery in 43.5 and 31.4% of cases, respectively, a percentage significantly higher than that for patients with other etiologies (P = 0.002). Prolapse-related AI usually responded to correction of the prolapse.

Conclusions: Patients with congenital, traumatic, and neurological AI tend to have greater symptom severity. Traumatic, rectal prolapse-related, and congenital AI cases more often require surgery.