Background: In patients with steroid-dependent nephrotic syndrome (SDNS), long-term remission (LTR) can usually be achieved with cyclosporin A (CSA), after alternative treatment with cytotoxic drugs or levamisole has failed. Nevertheless, severe SDNS recurs in some patients despite CSA maintenance therapy. Few data are available on the clinical course and treatment strategies in these patients.
Methods: We carried out a retrospective chart analysis of 46 patients with SDNS treated with CSA, after failure of cytotoxic treatment with cyclophosphamide (CPO). Median age at primary manifestation was 3.0 years (range 0.8-6.9) and median current age is 20.4 years (range 8.6-29.1). Patients were recruited from three centres caring for a total of 186 patients with steroid-sensitive nephrotic syndrome.
Results: In 14 of the 46 patients (30%; 10 male), severe SDNS recurred again despite CSA maintenance therapy. Seven patients relapsed beyond the age of 18 years. Nine of 14 patients received a further course of cytotoxic treatment as first intervention: six were treated with chlorambucil (CLA) and three with CPO. Four of the CLA-treated patients remained in LTR in contrast to none after CPO. Five patients received levamisole after CSA: only one went into LTR, while in one other CSA could be discontinued although further relapses occurred. One further patient was switched to CLA after levamisole, finally inducing LTR. Overall, six patients required two or more drugs, and in four of these CSA maintenance ultimately had to be restarted.
Conclusion: We conclude that SDNS can recur in patients despite CSA maintenance therapy. Treatment strategies for this subgroup of patients are complex and should be standardized to optimize long-term outcome. A subgroup of patients with childhood SDNS continues to relapse into adulthood.