Co-occurrence of PLA2R-positive membranous nephropathy without crescents, and PR3-positive eosinophilic granulomatosis with polyangiitis

Primary membranous nephropathy (PMN) is a common cause of adult nephrotic syndrome, most commonly associated with autoantibodies against M-type phospholipase A2 receptor (PLA2R). Eosinophilic granulomatosis with polyangiitis (EGPA), previously known as Churg-Strauss syndrome, is a rare disorder characterized by asthma, eosinophilia, and multiorgan vasculitis. Here, we report the case of an adult who presented with typical nephrotic syndrome. Renal biopsy revealed PLA2R-positive PMN without crescents. He had a history of asthma, eczema, and eosinophilia, and testing revealed positive serological proteinase 3 (PR3) and antineutrophil cytoplasmic antibody (ANCA). Further skin and bone marrow biopsy revealed histologic eosinophilic infiltration, and a diagnosis of EGPA was made. The renal biopsy revealed a few eosinophils in glomerular capillary lumen and tubulointerstitial. Treatment with a glucocorticoid and cyclophosphamide was initiated. At 32 months after completing therapy, the patient was in complete clinical remission, and the PR3-ANCA result was negative.