IgA Nephropathy

Description

• Most common form of glomerulonephritis in the world
• Renal parenchymal damage and dysfunction defined by deposition of IgA in glomerular mesangium
• Significant contributor to the incidence of end-stage renal disease (ESRD) in parts of Asia

Epidemiology

Incidence
In patients who undergo renal biopsy, the following incidence was reported: 30–40% in Asia, 15–20% in Europe, and 5–10% in North America

Prevalence

• Highest prevalence in Pacific Rim, particularly Japan and Korea
• More common in Asians, whites, and American Indians versus blacks in the United States and Africa

Etiology and Pathophysiology

Genetics

• Familial forms of IgA nephropathy (IgAN) exist with no specific gene identified.
• IgA1 molecules deposit within the mesangium leading to an inflammatory reaction with eventual fibrosis and scarring of the nephron.

Risk Factors

• Liver disease: Impaired removal of IgA by Kupffer cells in the liver predisposes individuals to IgA deposition in the kidney.
• Celiac disease: Ingestion of gliadin results in the formation of IgA antigliadin antibodies and deposition of immune complexes in the kidney.

Commonly Associated Conditions

• Henoch-Schönlein purpura
• Hepatic failure
• Celiac disease
• Rheumatoid arthritis
• Ankylosing spondylitis
• Reiter syndrome
• HIV
• CMV