Checking renal function does not necessarily detect nephritis, but needs to be combined with clinical manifestations and urine routine, 24-hour urine protein quantitative and so on to diagnose. Renal function tests include blood creatinine, urea nitrogen and glomerular filtration rate. Nephritis with proteinuria, hematuria, edema and hypertension as the main clinical manifestations, only renal function tests can not diagnose nephritis, need to be combined with urine routine, urine erythrocyte microscopic difference, 24-hour urine protein quantification, etc., and, if necessary, perform a renal puncture biopsy, in order to determine the pathological type of nephritis and the severity of the disease. If patients have recently developed symptoms such as waist pain, hematuria, proteinuria, etc., please do not self-medicate, it is recommended to go to the hospital for examination to clarify the diagnosis and standardize the treatment under the doctor’s guidance.