Prevalence and Factors Associated with Urologic Abnormalities in Hypospadias Patients

Objective: To estimate the prevalence of urinary tract abnormalities in boys with hypospadias and identify clinical factors that warrant screening. Materials and Methods: A retrospective review was conducted of patients with hypospadias treated at Siriraj Hospital between January 2014 and December 2023. No standardized radiographic screening protocol was applied. Results: Urinary tract abnormalities were identified in 6.2% (21/340) of patients with hypospadias. The most prevalent findings were vesicoureteral reflux (VUR) and hydronephrosis, primarily non-obstructive, non-reflux hydronephrosis. Ultrasound KUB was a valuable screening tool (n = 95), detecting 19 urinary tract abnormalities and 13 additional abnormalities. Analysis of KUB-related anomalies in hypospadias showed no direct relationship between urethral opening and the frequency of urinary tract abnormalities, except in coronal hypospadias, which demonstrated a higher rate of anomalies. On multivariable binary logistic regression, anorectal malformation (adjusted OR 13.95, 95% CI 2.47 - 78.63; p = 0.003) and undescended testis (adjusted OR 6.55, 95% CI 1.42 - 30.21; p = 0.016) predicted KUB abnormalities in patients with hypospadias. In the univariable model, cardiovascular abnormalities and coronal hypospadias were also significantly associated with urinary tract abnormalities (p = 0.015 and p = 0.006, respectively), with medium to high effect sizes. Conclusion: Of patients with hypospadias, 6.2% had anomalies of the urinary tract. It is advised that patients with hypospadias who additionally have anorectal anomalies or undescended testes undergo ultrasound KUB. Additionally, screening can be advantageous for patients with cardiovascular abnormalities or coronal hypospadias.