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.