What is kidney disease?

When experts talk about kidney disease, they usually refer to "renal function." According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), people with two healthy kidneys have 100 percent renal function, which is actually more than you need. This is why people can survive just fine with one kidney.

If renal function falls below 25 percent, serious health problems can occur. And if it drops below 10 to 15 percent, a person will not live long without dialysis or a kidney transplant.

While reduced renal function has several different causes (reviewed in the next section), there are generally three different types of kidney disease:

	Acute renal failure (ARF): This is when serious damage to the kidneys happens very quickly. An accident might cause this, as can some medications or poisons. In some cases, ARF can lead to permanent kidney damage.
	Chronic kidney disease (CKD): Most kidney problems, including those seen in HIV-positive people, happen slowly. CKD may be "silent" for many years, meaning that it doesn't cause any noticeable symptoms but may still be damaging the kidneys. CKD, left unchecked, can increases the risk of a heart attack or stroke. Routine laboratory testing can help detect CKD in the early stages, before it causes permanent kidney failure.
	End-stage renal disease (ESRD): This is total (or nearly total) kidney failure that cannot be reversed. Patients with ESRD require dialysis or a kidney transplant to stay alive. Of note, a study conducted by Johns Hopkins University in Baltimore suggests that the risk of ESRD among HIV-positive blacks is almost 12 times higher than in the HIV-negative black population—and that the risk may actually be increasing.

Search for news stories about this topic