Case Report: Anti-neutrophil Cytoplasmic Antibody-Associated Vasculitis Involving the Aortic Valve in a Twelve-year-old Girl
Abstract
Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides are a heterogeneous group of disorders characterized by necrotizing inflammation of small and medium vessels in the body in association with autoantibodies against the cytoplasmic region of the neutrophil (Plumb LA et al., Pediatr Nephrol 2018; 33: 25-39). The circulating autoantibodies in ANCA-vasculitides are directed against proteinase 3 (PR3-ANCA) or myeloperoxidase (MPO).
PR3-ANCA is most commonly observed in granulomatosis with polyangiitis (GPA), whereas MPO-ANCA is found primarily in renal-limited vasculitis and microscopic polyangiitis (Brogan P et al., Pediatr Nephrol 2018; 33: 187-198). The clinical course of ANCA-vasculitides may range from less severe to life-threatening systemic forms, but less severe courses are rare.
The latter may present a significant challenge to clinicians due to its rarity; life-threatening cases primarily affect elderly patients, although with an unclear incidence due to changes in classification criteria. Variable manifestations mimicking bacterial infections and other more common chronic inflammatory diseases further complicate diagnosis.
During a three-year study period in the Czech Republic (Dolezalova P et al., J Rheumatol 2004; 31: 2295-2299) only one child with ANCA-associated vasculitis was detected. The most frequent clinical features at disease presentation include lung, renal, otorhinolaryngologic, joint, skin, cardiac, and gastrointestinal involvement.
Early recognition and treatment, mainly immunosuppressive therapy, are crucial for positive outcomes. According to the recently published large studies, cardiac involvement in ANCA-associated vasculitis represents only a minority of all cases (McGeoch L et al., J Rheumatol 2015; 42: 1209-1212).
Recognized manifestations include pericarditis, arteritis, myocarditis, valvulitis, and conduction system defects (Korantzopoulos P et al., Cardiology 2004; 102: 7-10). This case report may help increase awareness of this potentially life-threatening disease among healthcare professionals, and emphasize cardiac valve involvement as an important sign in pediatric patients with ANCA-associated vasculitis.