Blood in urine may be kidney disease, blood in urine has many causes, it can be nephritis nephrotic syndrome, kidney stones, infection, tumor can also cause blood in urine, at this time we have to check urine red blood cell bitemporal further investigation, urine red blood cell bitemporal suggests are negative red blood cells, consider non-nephrogenic hematuria, such as kidney stones, infection, tumor caused by the middle urine culture, urine routine shows support the diagnosis of urinary tract infection;. Renal CT or cardiac ultrasound can exclude kidney stones; renal CT or cystoscopy can exclude bladder cancer or kidney cancer. If urine erythrocyte loci suggest the absence of red blood cells, this is the time to consider color urine, such as myoglobinuria due to blood transfusion, strong oxidants present in the urine, or rhabdomyolysis due to strenuous exercise. If the diagnosis of nephritis nephrotic syndrome, this time to improve further tests, such as check renal function, check serum protein electrophoresis, urine this week protein, check 24-hour urine protein quantification, this time to actively improve the relevant tests, there are indications for kidney biopsy recommended kidney biopsy to clarify the type of pathology, guide treatment and determine the prognosis.