Abstract
<jats:p>Background. ANCA-associated vasculitis in children is considered an orphan disease; however, renal involvement manifested as rapidly progressive glomerulonephritis determines the patient’s survival prognosis and the risk of end-stage renal disease. The purpose was to review scientific research and updated international protocols regarding the genetic determinacy, mechanisms of pauci-immune injury, diagnosis, and treatment of ANCA-associated nephritis in children. Materials and methods. The literature review was based on the analysis of scientific research results available in open access, using information retrieval systems such as PubMed, Web of Science, Scopus, Google Scholar, and ResearchGate. Sixty scientific papers, primarily published within the last 5 years, were reviewed in accordance with the selected topic and study objective. Results. The review details the 2012 Chapel Hill Consensus Conference nomenclature and genetic predisposition to ANCA-associated vasculitis (the role of HLA-DP and HLA-DQ loci). The primary diagnostic significance of detecting antibodies to proteinase-3 (PR3-ANCA) and myeloperoxidase (MPO-ANCA) via enzyme-linked immunosorbent assay is substantiated, demonstrating high specificity for the verification of granulomatosis with polyangiitis and microscopic polyangiitis, respectively. The specificity of “renal masks” and extrarenal manifestations (ENT pathology, alveolar hemorrhages) is described. Differential diagnosis with anti-glomerular basement membrane disease and immune complex nephritis is provided. The shift in the treatment paradigm based on the PEXIVAS trial evidence and the new KDIGO 2024 guidelines is highlighted: a strategy for rapid glucocorticoid load minimization (down to 5 mg/day by the 12th week) to preserve the child’s growth potential is substantiated. Particular attention is focused on the priority of rituximab as a steroid-sparing agent and the role of the Berden histological classification in predicting renal survival. An algorithm for pediatrician actions in cases of suspected rapidly progressive glomerulonephritis is substantiated. Conclusions. Early diagnosis verification using enzyme-linked immunosorbent assay for PR3/MPO antibodies and kidney biopsy according to KDIGO 2024 criteria is crucial. The implementation of targeted biological therapy and low-dose steroid regimens improves patients’ quality of life and reduces the incidence of disability.</jats:p>