A national health organization is offering free kidney screenings in Graniteville this week.

The screenings - available to those older than 18 - will be from 10 a.m. to 1 p.m. Thursday at the Aiken County Recreation Center on Jefferson Davis Highway.

Conducted by the South Carolina chapter of the National Kidney Foundation, the screenings will test for high blood pressure, high blood sugar and protein in urine.

According to Blakely Hallman, a marketing coordinator for the organization, the screenings in a mobile testing unit are part of the group's early evaluation program.

Residents do not need to fast for the blood test.

Chronic kidney disease affects nearly half a million people - one in eight adults - and most don't even know it, according to the organization.

It includes conditions that can damage vital organs and lead to kidney failure - which would require dialysis or a transplant - and increases a person's risk of heart and blood-vessel disease.

It can be caused by diabetes, high blood pressure and other ailments, according to the group.

Most at risk of getting chronic kidney disease are blacks, Hispanics, Pacific islanders, American Indians and senior citizens, the group says on its Web site, www.kidney.org.

Blood-pressure checks and urine tests are good for detecting the disease.

Symptoms of kidney disease include:

- less energy, fatigue;

- trouble concentrating and sleeping;

- poor appetite, nighttime muscle cramping;

- swollen feet and ankles, puffiness around the eyes, particularly in the morning;

- dry, itchy skin and frequent urination, especially at night.

Founded in 1950, the National Kidney Foundation is a voluntary health group that focuses on kidney and urinary tract diseases - preventing them, helping those inflicted with them and increasing organ-transplant availability.

To register for the screening, call (800) 488-2277.

Reach Sandi Martin at (803) 648-1395, ext. 111, or sandi.martin@augustachronicle.com.