Mycophenolate Mofetil for Severe IgA Vasculitis Nephropathy in Children: An Observational Study

Rationale & Objective: Individuals with IgA vasculitis nephritis (IGAVN) may develop rapidly progressive glomerulonephritis and/or nephrotic-range proteinuria, which are associated with worse prognosis. We report our experience of treatment of children with IGAVN with nephrotic-range proteinuria. Study Design: Case series. Setting & Participants: We retrospectively analyzed all children who presented with IGAVN, cutaneous purpura, and nephrotic-range proteinuria from January 1, 2000 until December 31, 2018. Outcome: We evaluated time required to achieve remission of proteinuria, resolution of hematuria, and glomerular filtration rate (GFR) at 12 months and last follow-up. Results: Twelve patients, 8 boys and 4 girls, mean age 7.5 years (range 4-15) were included in the study. Mean urinary protein to creatinine ratio (UPC) was 12.5 ± 8.7 mg/mg and GFR 90.7 ± 19.1 mL/min/1.73 m² before initiation of immunosuppression. All patients were treated with steroids and mycophenolate mofetil. Mean UPC declined progressively from 12.5 mg/mg to 4.6, 2.7, 0.3, and 0.2 mg/mg after 1, 3, 6, and 12 months, respectively. All patients achieved remission of proteinuria (UPC <0.3 mg/mg) and normalization of kidney function (GFR 102.2 ± 8.0 mL/min/1.73 m²) at 12 months. Immunosuppression was successfully withdrawn in all patients, and at last follow-up (mean 33.5 months), all patients except one remained in remission. All patients except one that relapsed maintained normal GFR at the last follow-up. Limitations: Retrospective study, single-center experience, no standard immunosuppressive protocol, lack of control group. Conclusions: Remission can be achieved in patients with IGAVN and nephrotic-range proteinuria using mycophenolate mofetil-based immunosuppression. Magnitude of proteinuria is a key laboratory finding that correlates with time to achieve remission. Prolonged follow-up of patients with severe IGAVN is warranted.