Membranoproliferative Glomerulonephritis over 20 Years at a Tertiary Referral Center in the UK.

Introduction: Membranoproliferative glomerulonephritis (MPGN) is a pattern of injury seen on kidney biopsy, with various underlying etiologies. The component types, including complement-mediated MPGN, are relatively rare. This study presents longitudinal real-world data over 20 years in a tertiary renal center in the UK.

Methods: All patients with an MPGN pattern on kidney biopsy between 2000 and 2020 were identified. After applying exclusion criteria, 38 patients remained. Data including patient demographics, details of the renal histology from the kidney biopsy, baseline laboratory results, treatments received, and clinical outcomes including renal replacement therapy and death were collected from the organization's electronic patient record.

Results: Twenty-eight of the cohort had immune complex-mediated MPGN, and 10 had complement-mediated MPGN (8 with C3 glomerulonephritis and 2 with dense deposit disease). Median follow-up was 72 months. Median age was 61 years. Overall, 60.5% were female, and 92.1% white. At presentation, median eGFR was 31.5 mL/min/1.73 m² and uPCR 394 mg/mmol. Here, 78.9% received renin-angiotensin-aldosterone system inhibitors and 71.1% received any immunosuppression. In total, 47.4% progressed to ESKD and 50% died during follow-up.

Conclusions: The study found an older patient population than typically reported. Poor outcomes were observed in the overall cohort with progression to ESKD and mortality both at almost 50%. This may be influenced by the older patient population. Individualized management of patients with an MPGN biopsy finding is paramount, with comprehensive evaluation for triggers and complement abnormalities. Going forward, registry enrolment and collaborative studies may enhance knowledge and outcomes.