Glomerulonephritis - Causes of glomerulonephritis

Glomerulonephritis is often caused by a problem with your immune system, although it's not always clear why this happens.

Immune system

Your immune system recognises infections and uses cells and antibodies to get rid of them. However, in some cases of glomerulonephritis, the immune system attacks healthy body tissue, including the tissue in the kidneys. It's not clear exactly why this happens, although sometimes it's part of a condition such as lupus or vasculitis.

The types of glomerulonephritis caused by problems with the immune system include:

ANCA vasculitis – antibodies damage the blood vessels in different parts of the body, including the kidneys
IgA nephropathy (immunoglobulin A nephropathy), also known as Berger disease – a build-up of an antibody called immunoglobulin A damages the kidneys
membranous nephropathy – antibody deposits cause the membranes of the glomeruli to thicken
lupus nephritis – glomerulonephritis is part of a severe form of lupus, known as systemic lupus erythematosus
membrano-proliferative glomerulonephritis (MPGN) – glomeruli have thickened membranes and contain extra cells, which can be caused by problems with the immune system or infections
anti-glomerular basement membrane disease, also known as Goodpasture’s disease – a very rare condition, where antibodies attack the membranes of the glomeruli

The terms crescentic glomerulonephritis and necrotizing glomerulonephritis are used to identify cases where inflammation is very severe. Crescentic and necrotizing glomerulonephritis can have various causes, but they are often caused by ANCA vasculitis, IgA nephropathy or lupus nephritis.

The immune system may also play a role in causing other types of glomerulonephritis, such as:

minimal change disease – the glomeruli are damaged, but the damage can only be seen with a special high-power microscope (minimal change disease causes nephrotic syndrome and is more common in children, but also occurs in adults)
focal and segmental glomerulosclerosis (FSGS) – there is inflammation and scarring of the glomeruli

Occasionally, these conditions are due to faulty genes that directly affect cells in the glomeruli.

Complication of infections

In some cases, the immune system abnormalities are triggered by an infection, such as:

HIV
hepatitis B and hepatitis C – viral infections of the liver
endocarditis (infection of the heart valves)

Inherited glomerulonephritis

Most people who develop glomerulonephritis don't have a family member with the condition. However, certain types of glomerulonephritis can run in families. For example, Alport syndrome – which causes damage to the blood vessels in the kidneys – can be inherited.

Some people with focal and segmental glomerulosclerosis (FSGS) also have an inherited condition where the problem results from a faulty gene. This is more common when the condition is detected in childhood or early adult life.

If you're diagnosed with an inherited type of glomerulonephritis, your doctor can advise you about the chances of someone else in your family being affected. They may recommend screening, which can identify people who may be at increased risk of developing the condition.