Most experts agree that you should see a kidney specialist, called a nephrologist, when your eGFR (estimated glomerular filtration rate—a measure of kidney function) is less than 30. Nephrologists are medical doctors who specialize in kidney care. A nephrologist specializes in the kidneys and diseases that affect them. Although your primary care doctor will work to help prevent and treat early stages of kidney disease, a nephrologist may be called in to help. Kidney failure, also called renal failure, is known as a “silent killer. Nephrology · Urology · Are you concerned about your kidney function? Talk with your primary care physician about seeing a nephrology specialist.