“It is well known that the four disciplines of comedy are ‘speaking, learning and singing’, but when it comes to the four disciplines of Chinese medicine, it is the ‘look, smell, ask and cut’, which is the ancient saying: look and know is called God. Looking is the first of the four diagnoses, but also can objectively reflect the disease condition, modern tests make Chinese medicine practitioners as if they have a ‘clairvoyant’, can see at a glance whether the patient has a kidney disease. How can we clinically ‘identify urine to know the disease’? Let’s find out below! Hematuria is a red flag and may be the only clinical manifestation of urological malignancy. The diagnosis of hematuria begins with identifying whether it is glomerular or non-glomerular hematuria. Glomerular hematuria is commonly associated with various primary or secondary glomerulonephritis, while non-glomerular hematuria is commonly associated with kidney stones and renal tumors. In case of glomerular hematuria, relevant tests are needed to exclude secondary glomerulonephritis before primary nephritis can be diagnosed. It is better to do kidney pathology examination. If it is non-glomerular hematuria, ultrasound, IVP examination, CT and MRI are needed to clarify the cause as soon as possible. Normal morphology of urine red blood cells has the same morphology of red blood cells seen in terminal blood smear, i.e., central depression, disc-shaped and yellowish. Urine red blood cells show abnormal morphology such as ring-shaped (fried doughnut-like), spiny, serrated (crinkled), target-shaped, shadow-shaped, mouth-shaped, fissured, small-shaped, and spherical-shaped red blood cells are called urinary malformed red blood cells. It is currently believed that the production of urinary aberrant red blood cells is mainly due to: (1) physical damage to urinary red blood cells through the diseased glomerular filtration membrane; (2) urinary red blood cells are affected by urinary PH, osmotic pressure and chemical factors such as urease and urea when flowing through the renal tubules. 1, homogeneous red blood cell criteria Red blood cells are uniform in size, uniform in variation, within two images, most are normal and mulberry-like red blood cells, and some can appear as shadow red blood cells. This type mostly belongs to non-nephrogenic hematuria. 2.Mixed red blood cell standard According to the different proportion of abnormal and homogeneous red blood cells, it can be divided into two types of mixed red blood cell hematuria (abnormal red blood cells > 50%) and mixed red blood cell hematuria (homogeneous red blood cells > 50%) with mainly homogeneous red blood cells. 3, determine the limit of urine in a variety of deformed red blood cells accounted for more than 80% of the total red blood cells, can be diagnosed as glomerular hematuria; urine red blood cell surface smooth, uniform size and shape, and less than 20% of deformed red blood cells suggest non-renal hematuria; if the urine deformed red blood cells accounted for more than 20% of the total red blood cells, but less than 80% is mixed hematuria. The results of the above 3 types of aberrant red blood cells, homogeneous red blood cells and mixed red blood cells are all convergent and not reversible, so it is more objective to observe with clinical symptoms. The urinary red blood cell volume distribution curve of patients with urinary tract infection can also show glomerular distribution. 2, glomerular disease can also be non-erythrocyte aberrant hematuria In patients with severe renal failure, urinary red blood cells can be normal in form due to the loss of osmotic pressure gradient in the renal tubules and the severe destruction of the glomerular base membrane. Therefore, although urine erythrocyte morphology testing is clinically important in the local diagnosis of hematuria, the local diagnosis of hematuria should not rely entirely on urine erythrocyte morphology testing, but should be analyzed and judged in combination with the patient’s clinical manifestations, urine protein condition and imaging findings.