Coronal urethrocutaneous fistula after hypospadias repair: A retrospective cohort study of risk factors for fistula recurrence.

Abstract

We aimed to evaluate whether coronal urethrocutaneous fistula (UCF) is an independent risk factor for UCF recurrence after hypospadias repair and identify potential risk factors, with particular attention to the urethral defect ratio (UDR) and interaction between fistula location and number. Clinical data from patients who underwent UCF repair between 2013 and 2022 were retrospectively reviewed. Patients were classified as having coronal or non-coronal UCF. Candidate variables included demographic factors, urethral defect length, operative features of the original hypospadias repair, interval variables, meatal stenosis, UDR, history of corpora cavernosa reconstruction, repeated urethral surgery, and fistula size and number. Univariable analyzes were performed first, followed by modified Poisson regression with robust variance to estimate relative risks. As fistula location significantly interacted with fistula number, stratified modified Poisson regression was subsequently performed. Overall, 136 patients were included and 31 developed recurrent UCF after a median follow-up of 36.2 months. In multivariable analysis, coronal UCF (RR 2.130, 95% CI 1.104-4.112, P=0.024), repeated UCF repair (RR 2.342, 95% CI 1.209-4.536, P=0.012), higher UDR (RR 4.296, 95% CI 2.693-5.899, P<0.001), and lack of prior corpora cavernosa reconstruction (RR 1.896, 95% CI 1.281-2.034, P=0.031) were independently associated with recurrence. A significant interaction was identified between fistula location and number. In stratified analysis, coronal location remained a significant risk factor in patients with a single fistula (aRR 2.682, 95% CI 1.169-6.155, P=0.020) but not in those with multiple fistulas (aRR 0.819, 95% CI 0.375-1.787, P=0.615). Coronal location, repeated fistula repair, higher UDR, and lack of prior corpora cavernosa reconstruction were associated with recurrence after UCF repair. In children with multiple fistulas, coronal location was not significantly associated with recurrence.