A SINGLE CENTRE EXPERIENCE OF LOW C3/C4 LEVELS AND OTHER LABORATORY ASPECTS IN TURKISH CHILDREN WITH IMMUNOGLOBULIN A VASCULITIS

Objective: Immunoglobulin A vasculitis (IgAV) is the most prevalent systemic vasculitis in childhood. This intricate immune-mediated vasculitis affects the small blood vessels in several organ systems. Complements 3 and 4 (C3 and C4) are constituents of the complement system; serum C3/ C4 measurements play aMaterial and Methods: A total of 124 children—60 IgAV patients and 64 healthy controls—were assessed in this study. The C3 and C4 levels were quantified using a turbidimetric immunoassays method with manufacturer details. The extractable nuclear antigen antibody (ENA) panels were evaluated using the ELISA method. The results were evaluated statistically. Results: The white blood cell count, neutrophil count, and neutrophil/ lymphocyte ratio were higher in the patient group compared to the control group (p=0.015, p=0.013 and p=0.039, respectively). CRP, ESR, and random urine protein/creatinine ratio (RUPCR) increased in patients than controls (p<0.001, p=0.002 and p<0.001 respectively). There was no difference in the lupus anticoagulant activity and low C3/C4 levels between the groups (p˃0.05). Conclusion: IgAV, an IgA-mediated systemic small vessel vasculitis, affects many organs. As a result, it is crucial to evaluate the laboratory results in the follow-up of the patient and the possible complications.