Successfully treated C3 glomerulopathy in which protein and genetic analyses were useful for diagnosis

Area of Science:

• Nephrology
• Immunology
• Complement System Biology

Background:

• C3 glomerulopathy is a rare kidney disease characterized by C3 deposition in glomeruli, stemming from complement dysregulation.
• Pathogenesis often involves alternative complement pathway dysregulation and terminal pathway activation, frequently driven by acquired factors like autoantibodies.

Purpose of the Study:

• To report a case of C3 glomerulopathy diagnosed via renal biopsy.
• To investigate the role of complement and genetic factors in the disease.
• To evaluate treatment response to corticosteroids.

Main Methods:

• Renal biopsy for diagnosis.
• Analysis of serum complement levels (C3, sC5b-9) and complement-related proteins.
• Genetic analysis of complement-related genes.

Main Results:

• The patient achieved complete remission within two months of corticosteroid treatment.
• Laboratory findings included low C3 levels and high soluble terminal pathway protein complex (sC5b-9).
• No pathogenic variants were identified in complement-related genes, supporting an autoantibody-mediated etiology.

Conclusions:

• The patient was diagnosed with C3 glomerulopathy associated with autoantibodies.
• Corticosteroid therapy demonstrated significant efficacy, supporting the diagnosis and treatment strategy.
• Complement and genetic analyses are crucial for understanding C3 glomerulopathy pathogenesis and guiding treatment.