IgA nephropathy, also called Berger's disease, is a kidney disorder that causes inflammation of the glomeruli, the individual filtering units of the kidney that produce urine.
The inflammation is produced by a buildup of a substance called immunoglobulin A (IgA) in the kidneys. IgA is a type of antibody manufactured by the immune system. When the body is unable to filter the urine, it can't excrete body wastes or eliminate excess fluid from the bloodstream. IgA nephropathy leads to renal (kidney) failure and other related complications. It may be acute (attacking quickly and suddenly) or chronic.
IgA nephropathy often strikes in the teen or early adult years. It affects more males than females.
No one knows what causes IgA nephropathy. Right now, researchers do know that having a family member with the disorder increases the risk of developing it. As well, there may be a connection between IgA nephropathy and Henoch-Schönlein purpura, a form of inflammation of the blood vessels that is more common in children.
Symptoms and Complications
The kidneys play three major roles in regulating the body:
- They filter urine to remove wastes from the body, keeping toxins from building up in the bloodstream.
- They regulate the minerals or electrolytes (sodium, calcium, and potassium, for example) and the levels of fluid in the body.
- They produce hormones that control other body functions such as blood pressure, bone maintenance, and the production of red blood cells.
A common symptom of IgA nephropathy is dark or bloody urine, especially following a bout of physical stress such as a cold.
IgA nephropathy is not always a progressive illness. In many cases, people with IgA nephropathy remain stable, do not develop kidney failure, and are able to have their symptoms treated effectively.
Doctors have found that about 25% of those with IgA nephropathy develop chronic kidney failure that progresses to end-stage kidney failure.
Symptoms of end-stage kidney failure include:
- decreased urination
- high blood pressure
- itchy skin
- loss of appetite
- muscle twitching or cramping
- nausea and vomiting
- puffy eyes, hands, and feet (called edema)
- shortness of breath
- weight loss
- a yellowish-brown tint to the skin
Making the Diagnosis
If IgA nephropathy is suspected, the doctor takes a thorough patient history, paying attention to any past infections or kidney problems. The doctor will do a physical exam, checking blood pressure and looking for some of the physical symptoms of kidney failure.
Urine and blood tests will be ordered. The urine is checked for elements that shouldn't be there, such as protein or red blood cells, while blood tests show if there's a buildup of body wastes in the bloodstream.
A definite diagnosis can only be made by a kidney biopsy. To do a biopsy, they insert a fine needle into the kidney, using ultrasound as a guide. With the needle, they take a tiny tissue sample, and then they check it under a microscope for protein deposits.
In rare cases, doctors may decide that an open biopsy is necessary. This procedure is performed by a surgeon, who makes an incision to view the kidney and any abnormalities.
Treatment and Prevention
There is no specific treatment for IgA nephropathy. The goal is to reduce symptoms caused by the kidney's inability to work properly, and to try to avoid the problems this can cause, such as chronic renal failure.
The health care team may suggest dietary changes to reduce the amount of salt and protein intake. A registered dietitian can help draw up a healthy eating plan that takes this into account. Fish oils may be added to the diet, although their benefit has not been clearly established. Certain blood pressure medications, such as ACE inhibitors, can help reduce protein spillage from the kidney. Corticosteroids and medications to suppress the immune system may also be used.
Hypertension (high blood pressure) may have been a warning sign of IgA nephropathy. If this is the case, it will be treated, usually with antihypertensive medications (medications for high blood pressure).
Hypertension is also a complication of most kidney disorders. If blood pressure isn't already high when a person is diagnosed with IgA nephropathy, doctors will watch closely for its development. Lifestyle changes (e.g., diet, exercise, stress management) to help avoid getting high blood pressure might be recommended.
If kidney damage gets worse, chronic kidney failure may set in. In these cases, kidney dialysis is necessary. Dialysis uses a membrane, instead of a kidney, to remove excess fluids and waste from the body.
Dialysis is not a cure, and people who are on dialysis must still follow special diets, restrict fluids, and take medications as prescribed by their doctors. The type of dialysis performed – peritoneal dialysis or hemodialysis – is chosen by the health care team according to the needs of the individual patient.
Peritoneal dialysis uses the natural membrane in the abdominal cavity, called the peritoneum, as its filter. Using a catheter (a very small, flexible tube) that's been permanently placed into the abdomen, the abdominal cavity is filled with a solution called dialysate, which stays there for a set amount of time. The dialysate then draws the waste and extra fluid out of the bloodstream through the membrane. When finished, the dialysate – now with the extra body fluid and waste mixed in – is drained out and then replaced with fresh dialysate.
This procedure is usually done at home, by the individual or by a family member. It is continuous and done in cycles. The cycles can take place as frequently as every 6 hours or, in some cases, only once a day (i.e., put in the dialysate at night and drain it in the morning). The procedure is done daily, but how often during the day varies according to the type of peritoneal dialysis.
Peritoneal dialysis doesn't work for everyone and may eventually stop working effectively for those who do use it. If this happens, hemodialysis is necessary.
Hemodialysis is a procedure that is usually done in a hospital or special clinic setting. In this process, the waste and excess body fluid are filtered out through the blood using a machine called a dialyser. The person's blood is pumped into the machine and stays on one side of the membrane, while the dialysate is on the other side of the membrane. As with the peritoneal dialysis, the dialysate draws the extra body fluid and waste through the filter and then the filtered blood is pumped back into the body. The process of hemodialysis is quicker than peritoneal dialysis, and the cycle is generally finished in about 4 hours. It's usually done about 3 times a week.
All those who require dialysis are assessed for a kidney transplant. As frightening as this may sound, kidney transplants are now quite common and have a good success rate. Someone who has had a successful transplant can go on to live a healthy life. Kidneys can be donated by a live donor (e.g., a relative) or by someone who has died and left his or her organs for donation.
It's entirely possible to live a full, healthy life with only one kidney – one fully functioning kidney can do the work of two – but it's essential to watch for signs of any problems with the remaining kidney.
Kidney transplant may be preferred over dialysis. Fewer than 15% of transplant recipients have the disease recur, so this is favoured in the long term for many patients.
Currently, there isn't any known way to prevent IgA nephropathy. That said, by being aware of the signs and symptoms of kidney disease, it's sometimes possible to delay its progression to kidney failure.