Evaluation of Serum Complement Components in Pediatric IgA Vasculitis: A Case-Control Study


Taşkın R. B., Aksu G., Şen S., HAKVERDİ G., Dörtkardeşler B. E., Conkar Tunçay S.

Children, cilt.12, sa.8, 2025 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 12 Sayı: 8
  • Basım Tarihi: 2025
  • Doi Numarası: 10.3390/children12081090
  • Dergi Adı: Children
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, CINAHL, Directory of Open Access Journals
  • Anahtar Kelimeler: complement factor H, IgA vasculitis, nephritis, pediatrics
  • Sivas Cumhuriyet Üniversitesi Adresli: Evet

Özet

Highlights: What are the main findings? Pediatric IgAV patients showed significantly reduced serum CFH levels compared to controls, regardless of nephritis status. Serum levels of sC5b-9, MBL, and MASP-1 did not differ between patients and healthy children. What is the implication of the main finding? Reduced CFH levels suggest a role of alternative complement pathway dysregulation in IgAV pathogenesis. sC5b-9, MBL, and MASP-1 are unlikely to serve as noninvasive biomarkers for renal involvement in IgAV. Background: IgA vasculitis (IgAV) represents the most frequently seen form of vasculitis among children. Although it often resolves without intervention, renal involvement (IgAV nephritis) poses a risk for long-term complications. Although the lectin and alternative complement pathways are possible causes in its development, dependable serum biomarkers for the early identification of nephritis remain unavailable. Methods: In this prospective case-control study, we examined how the serum levels of a membrane attack complex (sC5b-9), complement factor H (CFH), mannose-binding lectin (MBL), and mannose-binding lectin-associated serine protease-1 (MASP-1) relate to renal involvement in IgAV. These complement proteins were measured in children diagnosed with IgAV and compared to levels in healthy controls (HCs) matched for age and sex. Results: The study cohort comprised 44 IgAV patients with a median age of 8 years and 34 HCs. The CFH levels were reduced significantly in the patient group (median: 357.31 ng/mL; IQR: 228.32) relative to the controls (median: 543.08 ng/mL; IQR: 504.05) (p < 0.001). This decrease was observed irrespective of the presence of nephritis. There were no significant differences in serum sC5b-9, MBL, or MASP-1 levels between the patients and controls. Furthermore, no correlation emerged between these complement components and renal involvement. Conclusion: The data suggest that lower CFH levels may signal systemic dysregulation of the alternative pathway in IgAV. In contrast, the serum levels of sC5b-9, MBL, and MASP-1 appear inadequate as markers for predicting renal involvement. Further research with larger cohorts that includes genetic analyses and examination of kidney tissue is needed to better define the contribution of complement activation in IgAV-related nephritis.