(Urine pH is often acidic in patients with oxalate and urate stones; phosphate stones are often alkaline. In case of co-infection, more pus cells may appear in the urine, and in case of severe infection, the total number of white blood cells and neutrophils may be elevated in routine blood tests. (b) X-ray examination: X-ray examination is an important method to diagnose renal and ureteral stones. About 95% of urinary stones can be visualized on X-ray plain film. Supplemented with excretory or retrograde pyeloureterogram, it is important to determine the site of the stone, the presence or absence of obstruction and the degree of obstruction, whether the contralateral kidney function is good, to distinguish calcified shadows from outside the urinary tract, to exclude other lesions in the upper urinary tract, to determine the treatment plan, and to compare the site, size and number of stones after treatment. A pyelogram can show the exact site of the stone and provide insight into pelvic effusion and renal function. It also reveals a few negative stones that cannot be detected on plain radiographs, which appear as filling defects with smooth margins. The density of positive stones is similar to that of contrast and can be easily obscured, which can cause leakage or misdiagnosis, so the diagnosis must be compared with plain films. (c) Other tests: Ultrasound can detect dense light spots or light clusters at the stone site, and liquid flat segments when combined with hydronephrosis. CT scan is not as intuitive as X-ray and urographic film, and it is expensive, so it is usually not used as a routine test.