A normal kidney function test does not mean that there is no more kidney problem, for example, patients with chronic kidney disease usually progress to stage III before their kidney function becomes abnormal. In addition to kidney function test, in the simplest way, we also need to do urine routine laboratory test and urinary ultrasound. Look at urine routine mainly to see whether there is proteinuria, hematuria, leukocyturia, tubular type, etc., while ultrasound mainly to see whether there is no stone, obstruction, occupancy, and whether there is any abnormality in kidney morphology and structure. These two simplest tests can give us a basic judgment on whether there is any kidney problem.