To evaluate the clinical response of treatment-resistant membranous and membranoproliferative lupus nephritis to intravenous immunoglobulin (IVIg).
Seven lupus nephritis patients who failed to respond to at least prednisone and cyclophosphamide were studied. A kidney biopsy showing either membranous or membranoproliferative glomerulonephritis was available in six patients. They were treated with six courses (patients 1 and 2) or 1 or 2 courses (patients 3 through 7) of high-dose IVIg. For patients 3 through 7, the plasma levels of albumin, total cholesterol, urea, creatinine, dsDNA antibody titers, and daily proteinuria were measured just before the IVIg therapy, immediately on completion, and 6 months later.
All seven patients had a beneficial response to IVIg. In patient 1, decrease in proteinuria was evident 2 weeks after IVIg was started, nephrotic syndrome gradually disappeared, and she had no proteinuria in 3 years' follow-up. Decline in proteinuria was evident in patient 2 after the 4th IVIg course, but proteinuria reached the pretreatment level 4 months after the therapy ended. In patients 3 through 7, the mean daily proteinuria before IVIg (5.3 +/- 2.1 g) decreased after 1 or 2 IVIg courses (3.3 +/- 1.4 g), and further decreased when measured 6 months later (2.1 +/- 1.3 g). Similarly, the plasma cholesterol level decreased while the plasma albumin level increased after IVIg.
IVIg might be effective in treatment-resistant membranous or membranoproliferative lupus nephritis. Future studies should concentrate on determining the preferred treatment protocol of IVIg for the various classes of lupus nephritis.