IgA nephropathy is a kidney disorder that occurs when IgA (immunoglobulin A), a protein that helps the body fight infections, settles in the kidneys. IgA nephropathy can occur at any age, even in childhood. After many years, deposits of IgA may cause the kidneys to leak blood and sometimes protein in the urine. In the early stages, IgA nephropathy has no symptoms. The first sign of this condition may be blood in the urine. After 10 to 20 years, the kidneys may show signs of damage and 20-40% of adults develop end-stage kidney disease. In most instances, the cause of this condition is unknown; however, certain disorders have been linked with IgA nephropathy, such as cirrhosis of the liver, celiac disease, and HIV infection. Although IgA nephropathy usually occurs in a family with no other affected members, several cases of familial IgA nephropathy have been reported. Familial IgA nephropathy is suspected to run through families in an autosomal dominant manner and is linked to genetic material on the long arm of chromosome 6 (6q22-23). There is no cure for this condition. Treatment focuses on slowing the disease and preventing complications.