Treatment Patterns Among Adults and Children With Membranous Nephropathy in the Cure Glomerulonephropathy Network (CureGN)

INTRODUCTION: The 2012 Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guidelines for Glomerulonephritis recommend that patients with membranous nephropathy (MN) at risk for progression receive immunosuppressive therapy (IST), usually after 6 months of observation. A cyclophosphamide (CYC) or calcineurin inhibitor (CNI)–based regimen is recommended as first-line IST. However, the extent to which KDIGO recommendations are adopted in practice remains largely unknown. METHODS: We evaluated prescribing practice among patients with primary MN (diagnosed 2010–2018) enrolled in the Cure Glomerulonephropathy Network (CureGN) cohort study. We also evaluated the availability of testing for phospholipase A2 receptor (PLA2R) in the contemporary era. RESULTS: Among 361 patients (324 adults and 37 children) with MN who were IST-naïve at biopsy and had at least 6 months of follow-up, 55% of adults and 58% of children initiated IST <6 months after biopsy. Of these, 1 in 5 had no indication for (i.e., urine protein-to-creatinine ratio [uPCR] <4 g/g) or an apparent contraindication to (i.e., an estimated glomerular filtration rate [eGFR] <30 ml/min per 1.73 m(2)) IST. As first-line IST, half of treated patients received either CYC (16% of adults; 0% of children) or a CNI (40% and 46%, respectively), whereas 1 in 5 received corticosteroid monotherapy (20% and 27%, respectively) and 1 in 6 rituximab (15% and 15%, respectively). More than 80% of surveyed centers had access to PLA2R testing. CONCLUSION: These findings suggest that providers are not aware of, or lack confidence in, current KDIGO guidelines for MN. Treatment patterns observed in this cohort might critically inform the drafting of planned updates to KDIGO guidelines.