IgA Nephropathy (Berger's disease)
IgA is short for Immunoglobulin A, one of the types of antibody our body produces to fight infection. This circulates in the blood. “Nephropathy” is a scientific term for kidney disease.
In this condition, IgA settles in the kidney and causes scarring and inflammation within the kidney, which can only be seen clearly under the microscope. Therefore it is normally only diagnosed after a biopsy test of the kidney. What is seen under the microscope is that the “glomeruli”, which are the tiny structures which filter the blood to make urine, are damaged by deposits of IgA.
IgA nephropathy is one of a group of conditions called ‘glomerulonephritis’, where the immune system damages the kidney.
These are variable from case to case. In many cases there are no symptoms, but the damage to the glomeruli causes some blood to appear in the urine. This blood is often invisible, and only detected on routine medical check-ups. In other cases the blood may be visible, coming in attacks every so often. Sometimes an influenza type illness may spark off an attack of blood in the urine, which then clears after a few days.
Normally this condition is quite painless. However, in some patients who have acute attacks after the ’flu, there may be some pain over the kidneys and a feeling of sickness for a couple of days.
Basically doctors do not know fully. IgA is produced by glands around the throat and bowel to fight off infection. IgA is normally two antibody molecules stuck together. In IgA nephropathy, these molecules appear to get joined up in longer chains. As these travel around in the blood and pass through the kidney they get deposited in the filters (glomeruli) and then can cause an inflammatory reaction. It is not known why these IgA chains develop, and unfortunately no-one can stop this happening.
The outcome is very variable, and you will need to ask your specialist how things are likely to be in your case. The possibilities are:-
- It may continue unchanged for many years, requiring only regular check-ups with blood tests. This is probably the case in a majority of patients.
- It may go away on its own in some cases.
- In some cases kidney failure develops, leading to the question of dialysis and/or transplantation.
- High blood pressure may develop. This damages the kidneys and puts a strain on the heart and the rest of the circulation. Therefore high blood pressure should be treated vigorously.
- Kidney failure may sometimes occur. If so, it usually develops slowly, and your doctor will be able to give you an idea of how it is affecting you.
- There may be protein leakage from the kidneys. This may be slight and only detectable on urine tests, Occasionally there are high levels of protein leakage leading to swollen ankles and high levels of cholesterol in the blood. This is called nephrotic syndrome, and requires specialist assessment and treatment.
- There is a variant of IgA nephropathy called Henoch-Schonlein purpura. In this, the IgA antibodies affect not only the kidneys but also other parts of the body. A blotchy red rash may appear on the legs and buttocks. However, if you have had IgA nephropathy confined to the kidneys for some time, it would be very unusual for this to convert to the more serious Henoch-Schonlein purpura.
There is some evidence that some patients with deteriorating kidney function are helped with steroid (prednisolone) tablets. Your specialist will advise you whether such treatment should be tried in your case. Some specialists also use long term treatment with Maxepa (fish oil) tablets.
Drug treatment may be effective in Henoch-Schonlein purpura - doctors use steroids (prednisolone), sometimes together with another drug, either cyclophosphamide, azathioprine, or mycophenolate.
In most cases this condition does not affect normal life. There is no special diet that will make the disease go away or get worse. You can continue with physical exercise and sports quite safely. The condition does not generally run in families, so you need not worry about passing it on to your children. However, if you are planning a pregnancy you should discuss this with your doctor or someone familiar with looking after pregnant women with kidney problems.
There will be some queries if you apply for mortgages or life insurance, so plan ahead and be prepared to have your doctors asked to supply a medical report.
Adapted from a leaflet written by Rob Higgins, Renal Consultant, Walsgrave Hospital, Coventry, 1998
The National Kidney Federation cannot accept responsibility for information provided. The above is for guidance only. Patients are advised to seek further information from their own doctor.