Therapeutic plasma exchange in paediatric ANCA-associated vasculitis: a multicentre real-world experience

Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is a rare but potentially life-threatening condition in children, often presenting with severe multi-organ involvement. Although standard induction therapy includes cyclophosphamide or rituximab with glucocorticoids, the role of therapeutic plasma exchange (TPE) in paediatric AAV remains uncertain. This study sought to describe the clinical characteristics, indications and outcomes of paediatric AAV patients treated with TPE in real-world practice and to compare them with patients managed without TPE.

This retrospective multicentre study included children (<18 years) diagnosed with AAV according to EULAR/PRINTO/PRES criteria. Patients were classified into TPE-treated (TPE+) and non-TPE-treated (TPE-) groups. Demographic features, organ involvement, laboratory parameters, Paediatric Vasculitis Activity Score (PVAS), treatments, adverse events and outcomes were analysed.

Twenty-six paediatric AAV patients were included, of whom 11 (42.3%) underwent TPE. At diagnosis, the TPE+ group had significantly higher disease activity (median PVAS 12 vs 7, P = 0.004) and more severe kidney involvement, with higher serum creatinine and lower estimated glomerular filtration rate. Severe pulmonary, gastrointestinal, cardiovascular and cutaneous manifestations occurred predominantly in the TPE+ group. The primary indication for TPE was severe kidney involvement. TPE was associated with a significant reduction in PVAS (median 12.0-4.5, P = 0.007). Clinical improvement was observed in most acute organ-threatening manifestations, although persistent abnormalities remained common among patients with severe baseline kidney involvement. One patient died from catheter-related Pseudomonas aeruginosa sepsis during treatment.

TPE is selectively used as an adjunctive therapy in children with severe or refractory AAV, particularly in those with advanced kidney involvement. Although disease activity and acute organ-threatening manifestations improved following TPE, persistent renal abnormalities remained frequent, reflecting the severity of baseline kidney disease.