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

Area of Science:

• Pediatric rheumatology
• Immunology
• Nephrology

Background:

• IgA vasculitis (IgAV) is the most common vasculitis in children.
• Renal involvement (IgAV nephritis) can lead to long-term complications.
• Biomarkers for early nephritis detection in IgAV are lacking.

Purpose of the Study:

• To investigate serum levels of complement proteins in IgAV patients.
• To determine the relationship between complement factors and renal involvement in IgAV.
• To identify potential biomarkers for IgAV nephritis.

Main Methods:

• Prospective case-control study.
• Measured serum levels of sC5b-9, complement factor H (CFH), mannose-binding lectin (MBL), and MASP-1.
• Compared levels between 44 IgAV patients and 34 healthy controls (HCs).

Main Results:

• Significantly lower CFH levels in IgAV patients compared to HCs (p < 0.001).
• Reduced CFH levels were observed regardless of nephritis presence.
• No significant differences in sC5b-9, MBL, or MASP-1 levels; no correlation with renal involvement.

Conclusions:

• Lower CFH may indicate alternative pathway dysregulation in IgAV.
• Serum sC5b-9, MBL, and MASP-1 are inadequate predictors of renal involvement.
• Further research is needed to understand complement's role in IgAV nephritis.