IgA nephropathy is a kidney disorder characterized by blood in the urine. It is caused by inflammation of internal kidney structures and the deposit of IgA antibodies in kidney tissue.

It is also called Berger’s disease.

IgA nephropathy (Berger's disease) is a form of mesangial proliferative nephritis. It occurs when abnormal deposits of immunoglobin A build up inside the small blood vessels of the kidney. Structures in the kidney called glomeruli become inflamed.

The disorder can appear suddenly (acute), or progress slowly over many years (chronic glomerulonephritis).

Risk factors include having a personal or family history of IgA nephropathy or Henoch Schonlein purpura, a form of vasculitis that affects many parts of the body, and may cause a kidney lesion that is identical to the lesion of Berger's disease.

IgA nephropathy can occur in persons of all ages, but most often affects males in their teens to late 30s.

• Changes in color of urine - bloody, dark, brown, or rust colored
• Repeated episodes of dark or bloody urine

IgA nephropathy usually is discovered after one or more episodes of dark or bloody urine in a person with no other symptoms of kidney disorder.

Bloody urine may begin during or soon after a respiratory infection.

There are no specific changes seen during a physical examination. Occasionally, blood pressure may be high or swelling of the body may be present.

Tests that may be done include:

• Urinalysis
• Kidney biopsy (confirms the diagnosis)
• Urine immunoelectrophoresis