Most people don’t think much about their kidneys until something is really wrong. Considering they’re you’re built-in detox machines, you might want to pay closer attention to these fist-sized, bean-shaped organs. Sometimes referred to as the body’s “master chemists,” your kidneys sit just below your rib cage, one on each side of your spine.
They filter your blood to remove any waste and excess fluids, producing urine. They also ensure that you have the right amount of minerals, like potassium and sodium, in your blood; another key kidney job is producing hormones that help control your blood pressure.
“Most kidney disease is completely invisible, and people only find out about it after a routine test that measures kidney function. By this time, there is pretty significant disease,” cautions Joel Topf, MD, a nephrologist at Oakland University William Beaumont School of Medicine in Royal Oak, MI, and a spokesperson for the American Society of Nephrology.
According to Anil Agarwal, MD, director of interventional nephrology at The Ohio State University Wexner Medical Center in Columbus, Ohio, the best ways to diagnose kidney disease are through urine and blood screening tests. The urine test looks for blood proteins (which shouldn’t be in urine), bacteria, and minerals that can form kidney stones.
A blood test can detect a waste product from your muscles called creatinine; unhealthy kidneys have trouble filtering out creatinine. Creatinine is normally removed from your blood by your kidneys, but when kidney function slows, creatinine levels rise. “Urine and blood analysis are a good idea, and sometimes kidney ultrasound can provide more clues,” says Dr. Agarwal.