Plasma exchange and rituximab treatments in primary membranous nephropathy combined with crescentic glomerulonephritis: A case report.

Rationale: Crescent formation is rare in primary membranous nephropathy (MN). Anti-phospholipase A2 receptor (PLA2R) antibodies are detectable in these patients. The mechanism and treatments are unknown.
Patient Concerns: A 72-year-old female patient who presented with nephrotic syndrome, hematuria, and rapidly progressive kidney dysfunction.
Diagnoses: Kidney biopsy was performed and the diagnosis was MN in combination with crescentic glomerulonephritis. Circulating anti-PLA2R IgG3 and IgG4 were detected of high level.
Interventions: The patient received plasma exchange and rituximab besides corticosteroids.
Outcomes: The patient achieved complete remission of proteinuria and recovery of kidney function after the clearance of anti-PLA2R antibodies.
Lesson: This case suggests a pathogenic role of anti-PLA2R antibodies in the mechanism of crescent formation in MN, which may need intensive therapy to eliminate the antibodies quickly.