The Albumin/Creatinine Ratio (ACR) test is a urine test that measures the levels of albumin and creatinine in the urine. Albumin is a protein that is normally found in the blood, but should not be present in high levels in the urine. Creatinine is a waste product produced by the muscles that is filtered out of the blood by the kidneys and excreted in the urine. The ACR test is commonly used to screen for and monitor kidney damage in people with diabetes, hypertension, or other conditions that increase the risk of kidney disease. Elevated levels of albumin in the urine, combined with a low creatinine level, can indicate kidney damage or disease. The ACR test involves collecting a urine sample and measuring the levels of albumin and creatinine. Depending on the results of the test, doctors may recommend additional diagnostic tests or treatments to address underlying conditions and prevent further kidney damage. Regular monitoring of ACR levels can also be used to track the progression of kidney disease and evaluate the effectiveness of treatment.