Learning About APOL1-Mediated Kidney Disease

APOL1-mediated kidney disease, or AMKD, is a kidney disease linked to gene changes that can be passed down through families. Genes are parts of your cells that carry information from your parents.

Everyone has the APOL1 gene. This gene helps your body make a protein that can protect you from some infections. Some people are born with changes in this gene, called variants. Two APOL1 variants, called G1 and G2, can raise the risk of kidney disease.

These variants are more common in people with West African ancestry. But having two high-risk variants doesn't mean that you will get kidney disease.

AMKD is caused by being born with two high-risk APOL1 gene variants. It's not caused by anything you did. It's also not something you can catch from another person.

Experts think that some people may also need a "second hit" before kidney disease starts. A second hit is another stress on the body, such as an infection, illness, or certain medicines.

Knowing that AMKD can run in families may help you talk with your doctor about your risk. It may also help you to learn about genetic testing. This is testing that looks for gene changes.

AMKD often has no symptoms early on. You may feel well even if your kidneys are being harmed.

As kidney function gets worse, symptoms may include:

• Swelling in your legs or feet or around your eyes.
• Foamy urine. This can be a sign that protein is leaking into the urine.
• Feeling very tired.
• High blood pressure.
• Urinating more or less than usual.
• Loss of appetite.

These symptoms can have many causes. Having one doesn't mean that you have AMKD.

The doctor may use blood and urine tests to look for kidney damage. A blood test can measure creatinine, a waste product in the blood. This helps estimate your glomerular filtration rate, or eGFR, which is how well your kidneys filter blood.

A urine test can look for protein. Protein in the urine is called proteinuria. It can be a sign of kidney damage.

Genetic testing can show if you have two high-risk APOL1 variants. In some cases, your doctor may suggest a kidney biopsy. A biopsy means taking a very small piece of tissue to check it for signs of disease.

There is no cure for AMKD at this time. But treatment may help slow kidney damage and lower the risk of kidney failure. Kidney failure means that the kidneys can no longer keep your body healthy.

Treatment often focuses on lowering blood pressure and protein in the urine. Blood pressure medicines may be used. Some examples are ACE inhibitors and ARBs. These medicines can lower blood pressure and help protect the kidneys.

Healthy habits may also be part of care. These may include eating in a way that supports your kidneys, being active, and checking with your doctor before taking medicines or supplements that could harm the kidneys.

If the kidneys stop working well enough, dialysis or a kidney transplant may be needed. Dialysis filters waste and extra fluid from the blood. A kidney transplant is surgery to place a healthy kidney from another person into your body.

Researchers are also studying new medicines that target the APOL1 protein itself. This research may lead to more treatment options in the future.