RESUMO
To assess the value of proteinuria selectivity index [PSI] in predicting the response of children with nephrotic syndrome to corticosteroid therapy and its correlation with renal biopsy findings. Setting: Paediatric Department, Our Lady's Hospital for Sick Children, Dublin, Ireland. Design: Retrospective analysis of the records of 39 children admitted to the above hospital with nephrotic syndrome. PSI was performed for all children prior to therapy. All received corticosteroid therapy according to the protocol of International Study of Kidney disease in Children for initial attacks and relapses. Patients were divided into 3 groups according to their response to steroid; steroid responsive infrequent relapsers [n.15], steroid responsive frequent relapsers [10] and steroid resistant [8]. PSI of < 0.01 was statistically significant in differentiation between the steroid responsive and resistant nephrotic syndrome. All children in the latter group had non-minimal change lesions on biopsy. Protein selectivity index should continue to be one of the valuable initial tests in childhood nephrotic syndrome due to its useful additional predictive value on the response to steroid in those patients