Adequate Chelation and Cupriuresis in Hepatic Wilson Disease Patients Under Combination (Chelator + Zinc) Therapy at 2 Years of Follow-up

Abstract

Role of 24-h urinary copper excretion (UCE) in monitoring Wilson disease (WD) on combination (chelator+Zinc) therapy is not well studied, especially in the pediatric population. Hence, the present study is conducted with an aim to evaluate UCE and its role in deciding therapeutic adequacy in pediatric WD on long-term follow-up. All WD patients <18 years of age and on combination therapy with at least one UCE available after the first year of treatment were included. Liver biochemistries, UCE, and serum non-ceruloplasmin bound copper (NCC) were assessed at diagnosis and various follow-ups. For assessment of treatment efficacy, criteria for adequate chelation (CAC) were defined as fulfillment of both (i) AST & ALT ≤1.5 times upper limit of normal, serum albumin >35gm/L, INR <1.5 and (ii) UCE <500 mcg/day. Of the 74 included children, 70 (94.5%), 45 (60.8%), 28 (37.8%) and 21 (28.3%) completed 2-, 3-, 5-, and 7-year follow-up, respectively. Liver biochemistries improved significantly within 1 year of treatment. UCE (mcg/day) decreased significantly from baseline of 654.08±803.78 to 308.23±175.93 at 2 years with no further change at 3- and 5-years follow-up. UCE (mcg/day) at 2 years was <200 in 28.5%, 200-500 in 55.7%, and >500 in 15.7%. 61% achieved CAC in 2 years. On multivariate cox regression, treatment compliance was predictor for CAC achievement (Odds ratio: 3.48, 95%CI: 1.36-8.86. P=0.009). UCE declines significantly from baseline to <500 mcg/day within 2 years. Majority of treatment-compliant patients achieve CAC within 2 years of combination therapy.