Abstract: PUB144
Two Shots, One Kidney: A Case of Primary Membranous Nephropathy After Influenza and COVID-19 Vaccination
Session Information
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Author
- Osondu, Blessing U., Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, United States
Introduction
Primary membranous nephropathy (MN) is an autoimmune glomerular disease driven by antibodies against podocyte antigens, most commonly PLA2R. Environmental triggers, including infections and vaccinations, have been implicated in disease onset. Increasing reports suggest a temporal association between vaccination, including COVID-19 and influenza vaccines, and new-onset glomerular disease. In patients with a compatible clinical presentation, strongly positive anti-PLA2R serology may establish the diagnosis without the need for kidney biopsy.
Case Description
A 67-year-old man with no prior medical history developed nephrotic syndrome shortly after receiving influenza and COVID-19 vaccinations. Initial evaluation revealed nephrotic range proteinuria with preserved kidney function. Serologic testing demonstrated markedly elevated anti-PLA2R antibodies, and a diagnosis of primary MN was made without biopsy.
Supportive therapy was initiated, including optimization of an ACEi with excellent blood pressure control despite no prior diagnosis of hypertension. Given preserved kidney function and consideration of relapse risk, calcineurin inhibitors were deferred, and rituximab was administered for persistent nephrotic syndrome. Early follow-up demonstrated improvement in 24-hour urine protein, along with a marked reduction in lipid levels, resolution of volume overload to euvolemia, and stable kidney function. Notably, anti-PLA2R antibody levels, initially markedly elevated, normalized following therapy.
Discussion
This case highlights the role of serology-based diagnosis in primary MN and underscores a key clinical principle: immunologic and clinical improvements may precede reductions in proteinuria. In this patient, normalization of anti-PLA2R antibody levels and significant improvement in lipid profile and volume status occurred prior to substantial reductions in proteinuria, supporting the concept that proteinuria is a lagging indicator of disease activity. This is particularly relevant following B-cell–depleting therapy such as rituximab, where early proteinuria trends may underestimate treatment response. Additionally, this case raises awareness of vaccination as a potential trigger for MN, while acknowledging that causality cannot be established. Recognition of these patterns is important to avoid premature changes in management and to guide appropriate longitudinal monitoring.