The short- and long-term outcomes of membranous nephropathy treated with intravenous immune globulin therapy

Abstract

Background. A considerable diversity in prognosis is seen with membranous nephropathy (MN). A recent report showed beneficial effects of immune globulin (Glb) therapy in Heymann nephritis, a rat model of MN. However, the early and late clinical effects of Glb in human MN have remained unclear. Methods. We studied retrospectively 86 patients with primary MN from 1965 to 1988 who were followed for at least 5 years, or until renal or actual death. Thirty patients were non-randomly treated with 1-3 courses of intravenous immune globulin, 5-10 g/day (100-150 mg/kg/day) for 6 consecutive days. Based on electron microscopic (EM) findings, the patients were divided into two subtypes, i.e. homogeneous type with synchronous electron-dense deposits, and heterogeneous type with various stages of dense deposits, due to their different clinical outcomes. Results. There was no difference in the initial clinicopathological states between Glb (n = 30) and non-Glb group (n = 56) (70 vs 68% in nephrotic state; 37 vs 39% in female, 50 vs 52% in homogeneous type, 50 vs 48% in heterogeneous type respectively). For the homogeneous type, at 6 months post-treatment, Glb therapy had induced earlier remission as compared to non-Glb treatments with corticosteroid alone or together with cyclophosphamide (57 vs 10% respectively, P = 0.006). However, there was no significant difference in the early therapeutic effect for the heterogeneous type (13% for Glb vs 5% for non-Glb in remission after 6 months), or in the final outcome for all groups (18% for Glb vs 10% for non-Glb in renal death after 15 years). No adverse effects were recorded during or after Glb therapy. Conclusions. Our results suggest that short-term relatively low-dose intravenous Glb therapy has a beneficial effect in the earlier induction of remission in a subgroup of MN, the homogeneous type with EM findings of synchronous electron-dense deposits, but does not alter the long-term outcome of human MN.