The examination items of renal failure include blood test, urine test, imaging test, pathology test and so on. 1. Blood test: patients need to check blood routine, renal function, electrolytes and so on, so as to assess the working condition of the kidneys, and also to observe whether there is any complication. 2. Urine examination: it mainly includes urine electrolytes, urine routine, urine creatinine, urine precipitation, urine protein quantification, etc. The results of the examination can be used to assist in the diagnosis, so as to clarify the cause of the disease. However, avoid routine urine examination before infusion or taking diuretics, so as not to affect the results of the examination. 3. Phenomenological examination: patients can observe the morphology of kidneys through ultrasonography and determine whether there is urinary obstruction. And patients can also identify the cause of the disease through abdominal X-ray, abdominal CT, abdominal MR, renal angiography. 4. Pathological examination: If the above examination fails to find out the cause of the disease, it is necessary to carry out renal puncture biopsy, so as to diagnose systemic vasculitis, glomerulonephritis, acute tongue inflammation, acute interstitial nephritis and other diseases. It is recommended that patients with renal failure actively cooperate with doctors to carry out the above relevant examinations and take reasonable treatment measures.