Complement Activation in Patients with Focal Segmental Glomerulosclerosis.

Area of Science:

• Nephrology
• Immunology
• Clinical Medicine

Background:

• Pre-clinical studies suggest complement activation contributes to kidney injury in FSGS.
• Complement proteins are found in FSGS glomeruli, but their role (activation vs. trapping) is unclear.

Purpose of the Study:

• To determine if complement activation is part of the primary FSGS disease process.
• To measure complement activation fragments in FSGS patients' plasma and urine.

Main Methods:

• Analyzed plasma and urine samples from 19 FSGS patients and compared them to healthy controls and patients with CKD, vasculitis, and lupus nephritis.
• Measured levels of complement fragments Ba, Bb, C4a, and sC5b-9.

Main Results:

• FSGS patients had significantly higher plasma and urine Ba, C4a, and sC5b-9 levels at diagnosis compared to controls.
• Plasma Ba levels correlated inversely with eGFR and positively with proteinuria.
• Elevated complement fragments suggest active complement system involvement in FSGS.

Conclusions:

• The complement system is activated in primary FSGS.
• Elevated plasma Ba levels correlate with disease severity and may serve as a prognostic marker.
• Further research is needed to confirm findings and elucidate the prognostic significance of complement activation in FSGS.