Membranoproliferative Glomerulonephritis (MPGN)
Membranoproliferative nephropathy is one of a group of conditions called glomerulonephritis, where the immune system damages the kidney.
People use slightly different names for the same condition. Membranoproliferative is the same as mesangiocapillary. nephropathy, nephritis or glomerulonephritis are all used, but they all mean the same.
The name of the condition refers to the appearances of a kidney biopsy under the microscope. The glomerulus, the filtering unit of the kidney, is about the size of a pinhead. It is made up of membranes (which are capillaries that filter the blood), and a supporting structure called the mesangium. In this condition both the membrane and the mesangium are affected, and the mesangium shows signs of proliferation. Hence the name/names of the condition, which is distinct from other types of glomerulonephritis where only the membrane or only the mesangium are affected.
Because membranoproliferative nephritis can only be diagnosed with certainty under the microscope, it is only diagnosed after a biopsy test of the kidney. There are at least 2 different subtypes of membranoproliferative nephritis (type 1 and type 2), but they can be considered together from a practical point of view.
These are variable from case to case. In many cases there are no symptoms, but the damage to the glomeruli causes some protein to appear in the urine (Click here for information about proteinuria). In some cases the protein loss can be large enough to be associated with water retention, and swelling of the face, hands or feet. This is called nephrotic syndrome.
Basically doctors do not know fully. The immune system causes some damage to the kidney. In some cases of membranoproliferative nephritis there is an identifiable cause for the immune stimulation, for example a long term infection or abscess in the body. Occasionally a membranoproliferative nephritis may be seen in people with tumours, or hepatitis, or lupus, but more often the cause is not clear.
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 either only regular check-ups by a specialist or treatment if there is nephrotic syndrome. 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.
- In the long term, unfortunately, many people with this condition are at risk of getting kidney failure, leading to a need for dialysis or transplantation. There is also a risk of recurrent disease in a kidney transplant, and the chances of this happening in an individual case should be discussed, as the risk depends on several factors.
- There may be protein leakage from the kidneys. This may be slight and only detectable on urine tests, or 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.
This is not an easy condition to treat, and usually doctors rely on treatment of the high blood pressure. If the cholesterol is very high, treatment to reduce the levels may help.Some people may benefit from drugs which affect the action of platelets in the blood, and some from treatment that reduces the activity of the immune system. The value of drug treatment depends on many factors, and is best discussed on an individual basis.
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, though if the blood pressure is high or there is water retention, salt should be restricted in the diet. Physical exercise and sports can be undertaken. Occasionally this condition does run in families, and someone should tell their doctors if there is any evidence of kidney disease in the family. If someone is planning a pregnancy this should be discussed with the doctor in advance, as careful monitoring is required during pregnancy, and there is a chance that the condition could get worse.
There will be some queries with applications for mortgages or life insurance, so someone should plan ahead and be prepared to have the doctors asked to supply a medical report.
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.