Nephropathy is damage, disease, or other problems with the kidney. IgA nephropathy is a kidney disorder in which antibodies called IgA build up in kidney tissue.

It is also called Berger's disease.

Nephropathy - IgA; Berger's disease

IgA is a protein called an antibody that helps the body fight infections. IgA nephropathy (Berger's disease) occurs when too much of this protein is deposited in the kidneys. IgA builds up inside the small blood vessels of the kidney. Structures in the kidney called glomeruli become inflamed and damaged.

IgA nephropathy (Berger's disease) is a form of mesangial proliferative nephritis.

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

Risk factors include:

• A personal or family history of IgA nephropathy or Henoch Schonlein purpura, a form of vasculitis that affects many parts of the body
• Caucasian or Asian ethnicity

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

There may be no symptoms for many years.

Symptoms include:

• Bloody urine that starts during or soon after a respiratory infection
• Repeated episodes of dark or bloody urine
• Swelling of the hands and feet
• Symptoms of chronic kidney disease

IgA nephropathy usually is discovered when a person with no other symptoms of kidney problems has one or more episodes of dark or bloody urine.

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

Tests include:

• Blood urea nitrogen (BUN) blood test to measure kidney function
• Creatinine blood test to measure kidney function
• Kidney biopsy to confirm the diagnosis
• Urinalysis
• Urine immunoelectrophoresis

The goal of treatment is to relieve symptoms and prevent or delay chronic renal failure.

You may get medicines to control high blood pressure and swelling (edema), such as angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs). Controlling blood pressure is the most important way to delay kidney damage.

Corticosteroids, other drugs that suppress the immune system, and fish oil have also been used to treat this disorder.

Salt and fluids may be restricted to control swelling. A low to moderate protein diet may be recommended in some cases.

Some people will need to take medicines to lower their cholesterol.

Eventually, many patients must be treated for chronic kidney disease and may need dialysis.

For additional information and support, see the IgA Nephropathy Support Network website (www.igansupport.org).

IgA nephropathy gets worse slowly. In many cases, it does not get worse at all. Your condition is more likely to get worse if you have:

• High blood pressure
• Large amounts of protein in the urine
• Increased BUN or creatinine levels

About 25% of adults with IgA nephropathy develop end-stage kidney failure within 25 years.

• Acute nephritic syndrome or nephrotic syndrome
• Chronic kidney failure
• End-stage kidney disease

Call your health care provider if you have bloody urine or if you are producing less urine than usual.

Appel GB. Glomerular disorders and nephrotic syndromes. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 122.

Nachman PH, Jennette JC, Falk RJ. Primary glomerular disease. In: Brenner BM, ed. Brenner and Rector's The Kidney. 8th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 30.