Clinical presentations, treatments, and outcomes of pediatric lupus nephritis: a prospective cohort study from the Pediatric Nephrology Research Consortium

BACKGROUND: There are few prospective studies of mycophenolate mofetil (MMF) versus cyclophosphamide (CYC) for pediatric lupus nephritis (pLN) and none evaluating rituximab (RTX). METHODS: The Prospective Pediatric Lupus Nephritis Registry (ProPeL-R) enrolled patients < 21 years within 4 weeks of an initial kidney biopsy diagnostic of pLN. Demographic, clinical, and laboratory data were collected prospectively at enrollment, 3 months, 6 months, and then every 6 months thereafter for up to 5 years of follow-up. For this study, we compared patients receiving initial therapy with corticosteroids (CS) and either MMF (n = 33) vs. CYC (n = 18), and those treated with CS, either MMF or CYC, with RTX (n = 20) vs. without RTX (n = 51). RESULTS: Histology consisted of 18% class III; 35% class IV; 25% mixed class; and 22% pure class V. Eighty-two percent were female. No significant differences in response or infection rates were identified between those receiving MMF or CYC. There was a significant increase in combined complete (CR) and partial response (PR) at 24 months with RTX use. Overall CR rates at 6 and 24 months were 35% and 58%, respectively. At 24 months, 51% of patients continued on CS, and 56% of patients experienced at least one CS side effect. CONCLUSIONS: MMF and CYC had similar efficacy as initial therapies for pLN. RTX may augment long-term response. However, response rates were suboptimal. Large variations in initial therapy were observed. Given the paucity of prospective data in pLN, our study further illustrates the need for data-driven, pediatric-specific protocols to standardize care and improve outcomes.