In clinical work, many parents of children often ask me about the white color of their children’s urine, especially in winter when it is often found that the urine container will be white and there will be white precipitates at the bottom, is this normal? First of all, we need to know that normal urine contains substances such as urine pigment, urobilin and urorubin, so it is often light yellow. In the physiological state, urine color is related to urine volume, urine PH, endogenous or exogenous pigments (including food and drugs, etc.). White urine means that the urine appears white or milky and is usually seen in pus, celiac disease, lipiduria, and salt urine. Clinically, denatured white blood cells are referred to as pus cells. When fresh clean mid-centrifugal urine is microscopically examined for leukocytes >5/HP, or when piles of leukocytes are found microscopically, it is called microscopic pus urine. Urine with clots containing a large number of leukocytes is called sarcoid pusuria. Pus urine is commonly seen in urinary tract infections, such as pyelonephritis, but also in acute and chronic glomerulonephritis, acute progressive nephritis, renal tubular acidosis, renal calcification and non-infectious disorders of the urinary tract, such as stones and tumors. Celiac disease contains lymphatic fluid, consisting of gelatinous celiac particles and proteins, which are clarified by the addition of ether. In mild to moderate cases, it is not stratified; in severe cases, it can be divided into three layers after resting: the upper layer is fat; the middle layer is milky or lighter liquid containing small clots; and the lower layer is red or pink precipitate. It may be accompanied by hematuria or pus urine, called celiac hematuria or celiac pus urine. Celiac disease is commonly seen in filariasis and abdominal tuberculosis, abdominal, retroperitoneal and mediastinal tumors or trauma. When fat droplets are mixed in the urine, it is called steaturia. If the cells are ruptured, the fat droplets may also be free in the urine in the form of birefringent microscopic bodies. It is often seen in nephrotic syndrome, tubular degenerative disease, adipose tissue trauma or bone marrow fat embolism after fracture. Salt urine is caused by the precipitation of urinary hydrochloric acid, phosphate or other salt crystals, which become clarified after the addition of acid, more common in alkaline urine and winter, and has no clinical significance. Pay attention to hydration to reduce uric acid salt concentration in the urine. However, if more amino acid, uric acid, carbonate or oxalate crystals are seen, they may be related to stone formation. The presence of urinary crystals may also be seen in metabolic disorders. They are commonly seen in urinary tract stones, disorders of uric acid metabolism, and on sulfa drugs. When you find abnormalities in your child’s urine, it is best to have the urine tested for a definitive diagnosis.