Prognostic significance of the early course of minimal change nephrotic syndrome: report of the International Study of Kidney Disease in Children.

The ability to predict the course in children with newly diagnosed minimal change nephrotic syndrome (MCNS) may have significant therapeutic implications. Previous attempts based on data available at disease onset have not been successful. Therefore, it was investigated whether characterization of the initial response to adrenocortical steroids and the course during the early months of disease are predictive of the subsequent outcome. Three hundred-eighty-nine children with MCNS, diagnosed at onset, were treated with standard prednisone regimens and monitored for up to 17 yr (mean, 9.4 yr). They were classified, after 8 wk of therapy, as initial responders (complete remission) or initial nonresponders (continued proteinuria). Subsequent classifications included nonrelapsers, infrequent relapsers, and frequent relapsers. At 8 yr of follow-up, 80% of patients were in remission. Three-fourths of initial responders who remained in remission during the first 6-month period after initial therapy (nonrelapsers; 40% of the entire series) either continued in remission during their entire course or relapsed rarely. In contrast, initial relapsers, both frequent and infrequent, achieved a nonrelapsing course only after an average of 3 yr. Unremitting proteinuria during the initial 8 wk of treatment was followed by progression to ESRD in 21%. When proteinuria during the initial 8 wk continued through the subsequent 6 months, progression to renal failure occurred for 35%. Although 95% of children with MCNS do well, 4 to 5% die from complications or undergo progression to ESRD. Documentation of the early course aids in identifying those at increased risk for a poor outcome. More aggressive therapy may be indicated for these individuals.