Management and outcomes of pilonidal patients with secondary sinuses-a cohort study.

Background: Patients with pilonidal disease (PD) can present with concurrent draining secondary sinus at the superior gluteal cleft. The natural disease course in the setting of this severe phenotype is poorly characterized. We present the largest cohort of patients with PD and concurrent secondary sinus.

Methods: Patients with PD and concurrent secondary sinus who underwent Gips procedure with secondary sinus excision from 2019 to 2023 were prospectively followed. Patient demographics, drainage recurrence, symptom resolution, treatment, and follow-up period were recorded. Recurrent drainage from previous secondary sinus site was defined as isolated painless serous drainage after the wound had closed for > 3 weeks; recurrent PD was characterized as recurrent pain and bloody drainage after excision.

Results: One hundred and five patients (seventy-one males) with a median age of 17.2 years [interquartile range (IQR):15.4-19.0] underwent excision of their disease and were followed for a median of 367.0 days (IQR: 173.2-658.8). Without regular epilation, six patients (5.7%, five males, one female) had recurrent PD. With regular epilation, three patients (2.8%, three males) had recurrent PD. Eight patients (7.5%, six males, two females) had recurrent secondary sinus site drainage. Median time to recurrent drainage was 75.5 days (IQR: 65.2-216.2) after excision and for recurrent drainage to resolve was 72 days (IQR: 49-81). Recurrent secondary sinus site drainage was treated with antibiotics, silver nitrate, debridement, or no treatment.

Conclusion: Patients who present with PD in the setting of concurrent secondary sinus have a unique, more severe disease phenotype. Excision can be complicated by recurrent drainage from the secondary sinus site that can resolve without repeat surgical excision.