Anoscrotal fistulas: causes and management in a 10-year French case series

Anoscrotal fistula is a rare variant of anal fistula, often mimicking primary scrotal disease and causing diagnostic delay. Unlike typical cryptoglandular fistulas, anoscrotal extensions are frequently linked to Crohn's disease, tuberculosis, hidradenitis suppurativa, or actinomycosis. Published data remain scarce, especially in Europe. This study aimed to describe the clinical features, etiologies, imaging findings, management, and outcomes of anoscrotal fistulas treated in a French tertiary center.

We retrospectively reviewed all men managed for anoscrotal fistula at the Institute of Proctology, Paris Saint-Joseph Hospital, between 2014 and 2024. Demographic, clinical, radiological, surgical, and outcome data were analyzed. Healing was defined as closure of all fistula openings without recurrence at last follow-up.

Twenty-nine patients were included (mean age 48.2 years). Initial presentation was abscess in 55% and purulent discharge in 45%. External scrotal openings were present in 90%. Magnetic resonance imaging (MRI) identified complex tracts in 59% of cases. Etiologies were cryptoglandular (63%), Crohn's disease (15%), hidradenitis (11%), tuberculosis (7%), and actinomycosis (4%). Nineteen patients (66%) had prior anorectal surgery. Most (72%) underwent initial seton drainage, followed by fistulotomy (31%), advancement flap (12%), or other sphincter-preserving techniques. A urologist was involved in 31% of cases. After a median follow-up of 22 months, 59% healed, 28% had persistent disease, and none recurred once healed. Continence was preserved, and 73% of patients were highly satisfied. No predictors of healing were identified.

This series represents one of the largest European experiences with anoscrotal fistula. Findings emphasize frequent non-cryptoglandular causes, the key role of MRI, and the need for multidisciplinary, individualized management.