Late Relapses of Membranous Nephropathy: A Case Series

Background: Relapse of the nephrotic syndrome is common among primary membranous nephropathy (MN) patients. Relapses of MN typically occur within a few years of achieving disease remission. There is limited description to date regarding MN patients who have late relapse of MN, i.e. after more than five years of sustained disease remission. The objective of this case series was to report the clinical course of MN patients with late relapse. Methods: We analyzed the patient database of the Center for Glomerular Diseases at Columbia University to identify patients seen at our center who had relapse of biopsy-proven MN at least five years after achieving sustained disease remission. Results: We identified 16 patients with late MN relapse. The median time in sustained remission prior to relapse was 10.2 (range 7-29.0) years. Ten (62.5%) patients were diagnosed with late relapse based on laboratory monitoring alone without clinical symptoms of the nephrotic syndrome. Fourteen (87.5%) patients received immunosuppression during their initial presentation and late relapse. Patients had favorable long term renal outcomes over a median 21 (range 12-56) year follow-up period with 14 (87.5%) patients in remission at study conclusion and median decline in eGFR per year -0.63 (range -6.3 - 17.5) ml/min/1.73m2/year. Conclusions: This case series highlights a previously under-appreciated and likely rare outcome of MN, namely late relapse. Late relapse patients, having a longer time in sustained remission, may have a more favorable long-term renal outcome.