Urinary KIM-1 and CA 19-9: Biomarkers for Guiding Treatment Decisions after Pyeloplasty

Abstract

Introduction Urinary biomarkers KIM-1 and CA 19-9 are being evaluated as diagnostic indicators for congenital obstructive hydronephrosis in pediatric patients. This study focuses on the quantification of these biomarkers pre-and post-surgery, correlating their levels with ultrasonographic findings and histopathological assessments to refine diagnostic accuracy and therapeutic approaches. Biomarker analysis aids in identifying candidates for surgical intervention and addresses the challenge of persistent obstruction following pyeloplasty, facilitating timely, targeted treatments to safeguard renal function. Methods This two-year prospective analysis examined urinary KIM-1 and CA 19-9 concentrations in 40 pediatric patients diagnosed with UPJO. The study cohort included individuals below 16 years of age, provided follow-up consent was obtained. A total of three cases were excluded due to either loss to follow-up or the necessity for repeat surgical intervention. Urine specimens were collected at baseline (pre-operative) and at 1, 3, and 6 months’ post-operative intervals, with biomarker quantification conducted using ELISA kits. Diagnostic evaluation included ultrasonography and nuclear imaging modalities. Statistical analyses were performed, and significance was established at P-value<0.05. Results The study included 37 cases of UPJO requiring pyeloplasty, alongside healthy controls. Among the cases, 51.3% were children aged 1–5 years, with a male predominance of 81.08%. Post-operative outcomes demonstrated a statistically significant reduction in the antero-posterior diameter (APD). Urinary biomarkers KIM-1 and CA 19-9 exhibited a notable post-operative decline, with KIM-1 showing a more substantial decrease. The sensitivity and specificity of CA 19-9 marginally exceeded those of KIM-1. Conclusions Urinary biomarkers KIM-1 and CA 19-9 effectively monitor pyeloplasty outcomes in children with congenital obstructive hydronephrosis, providing a cost-effective, child-friendly alternative to renal scans, ensuring timely interventions, safeguarding kidney function, and reassuring families. © 2025 Urology Research Center (URC), Tehran University of Medical Sciences.