Outcome of rituximab treatment in children with non-dialysis-dependent anti-GBM disease.

ABSTRACT

BACKGROUND: Anti-GBM disease is a rare vasculitis mediated by pathogenic antibodies against collagen IV. Anti-GBM disease presents with rapid progressive glomerulonephritis and leads to kidney failure if untreated. KDIGO recommends plasma exchanges (PEX) for antibody elimination and steroids plus cyclophosphamide (CTX) to suppress antibody production. CTX is associated with severe side effects including gonadal toxicity. Rituximab (RTX) and mycophenolate mofetil (MMF) might be a less toxic but equally efficient alternative to CTX. Studies in pediatric anti-GBM disease patients receiving RTX and MMF instead of CTX are lacking. METHODS: A retrospective survey in 8 tertiary German centers was performed. The clinical data of patients diagnosed between 2014 and 2022 were collected and analyzed. RESULTS: Five adolescent patients treated with PEX and RTX and/or MMF due to anti-GBM disease were analyzed. All patients had anti-GBM antibodies, hematuria, glomerular proteinuria, and pulmonary hemorrhage. eGFR was 124 ml/min/1.73 m2 (range 47-162), and all patients were non-dialysis-dependent but with relevant histological kidney affection (mean crescents on kidney biopsy 77%). Antibody clearance was achieved after 13 PEX cycles (range 6-31). Four out of 5 patients received methylprednisolone pulses. All patients received oral prednisolone and MMF, and four patients received a median of 4 RTX doses (range 2-4). After a mean follow-up of 27 months, 4/5 patients had conserved or improved kidney function, while one patient (20%) developed kidney failure. CONCLUSIONS: In this small series of pediatric non-dialysis-dependent anti-GBM disease patients, first-line treatment with RTX and MMF showed a favorable kidney outcome in 4/5 cases and had an acceptable side effect profile.