African Americans with HIV are about nine times more likely to develop kidney disease than positive people from other racial and ethnic groups.

Why does HIV, which targets the immune system, promote kidney damage in one group more than others?

Researchers are trying to figure that out, and they’ve found one link.

Because of a genetic mutation that occurred in sub-Saharan Africa around 5,000 years ago, people of African descent with two copies of a gene called APOL1 carry a heightened lifetime risk of developing kidney disease. And if an HIV-positive person has two copies of APOL1 (one inherited from each parent), but is not on HIV medications, the risk of developing a form of kidney disease called HIV-associated nephropathy (HIVAN) increases by up to 50 percent. Doctors think HIV may aggravate the higher risk already present in people with two copies of APOL1. And having hepatitis B or C along with HIV may add to kidney disease risk.

But HIV-positive people of all ethnicities lower their kidney disease risk when they take HIV medications. So taking those meds faithfully both supports general health and lowers kidney disease risk. If you have diabetes or hypertension, controlling your blood sugar and monitoring blood pressure promote kidney health too.

More good news: Detecting kidney disease early allows more flexibility in treatment. “People newly diagnosed with HIV should be tested [right away] for chronic kidney disease,” says Bryan Becker, MD, former National Kidney Foundation president. Simple blood and urine tests at your regular checkups can test kidney function.

For more, watch video interviews with HIV specialist Theresa Mack, MD, and Mechelle Jones, who is living with HIV and kidney risk, at poz.com/kidneys.