Value of urinary carbohydrate antigen 19-9 to predict failure of conservative management in children with ureteropelvic junction obstruction.

Abstract Objective To assess the role of urinary carbohydrate antigen 19–9 (CA19–9) measurement in determining optimal management of ureteropelvic junction obstruction (UPJO) and predicting failure of conservative management. Patients and methods Children with UPJO diagnosed between December 2012 and April 2015 were included. Depending on clinical and para-clinical findings, patients were divided into three groups: Group 1 consisted of patients who were considered for non-operative management with improvement of the condition during the course of follow-up. Group 2 were suitable for observation; however due to deterioration of condition pyeloplasty was indicated after a period of observation. Group 3 patients required immediate pyeloplasty. Urinary CA19–9 was measured in all patients at baseline and compared between the study groups. Results A total of 112 children (115 affected kidneys) with UPJO and mean age of 18.6 ± 3.3 months were assessed. Group 1, 2, and 3 consisted of 54(48.2%), 24(21.4%), and 34(30.4%) patients, respectively. Mean baseline urinary CA19–9 was 37.83 ± 5.20, 145.45 ± 18.38 and 244.62 ± 41.42 in groups 1, 2 and 3, respectively. Multivariate analysis showed that both CA19–9 and APD are independent predictors of need for surgery in patients on observation. ROC curve analysis revealed that urinary CA19–9 level at cut off value of 52.6 U/mL had sensitivity of 92.0% and specificity of 70.9% in predicting failure of non-operative management. Conclusion Higher urinary CA19–9 level is associated with failure of non-operative management in patients with UPJO. Such patients may require close follow-up and assessments to prevent irreversible damage to the kidney. Type of Study Study of Diagnostic Test. Level of Evidence Level II.