Urine protein can still be detected when water is added to the urine, but the concentration of urine protein will decrease. Under normal circumstances, human urine does not contain protein, or only contains a small amount of protein. If the protein is found to be higher than normal during the test, it can indicate specific kidney pathology, such as chronic glomerulonephritis or other diseases that cause kidney damage, such as hypertensive kidney damage, diabetic nephropathy, rheumatoid immune nephritis can all appear elevated urine protein. So the human body can detect protein if water is inadvertently added to the sample after the urine sample is taken. Whenever there is an elevation of protein, it is necessary to investigate the kidney disease to determine whether there is a functional or organic change in the kidney.