1. Classification of proteinuria: 1. Glomerular proteinuria This is the most common type of proteinuria. According to the degree of damage to the filtration membrane and the components of urine protein, urine protein is divided into 2 categories: (1) Selective proteinuria: clinical urine protein qualitative 3+ to 4+, quantitative more than 3.5g/24h, common in nephrotic syndrome. (2) Non-selective proteinuria: reflecting severe fracture and damage to the glomerular capillary wall. Non-selective proteinuria is a kind of persistent proteinuria, which has the risk of developing into renal failure and often indicates a poor prognosis. It is commonly seen in primary or secondary glomerular disease. 2.Tubular proteinuria Urine protein qualitative 1+～2+, quantitative 1～2g/24h. Commonly found in renal tubular damage disease. 3.Mixed proteinuria Proteinuria is produced when glomerular and tubular disease are involved simultaneously or successively. It is characterized by both types of proteinuria, but the proportion of each component is not consistent depending on the site of lesion damage, and may also vary depending on the degree of glomerular or tubular damage. Overflow proteinuria refers to proteinuria formed when the relative molecular mass of small or positively charged proteins in the plasma is abnormally increased and exceeds the tubular reabsorption capacity through glomerular filtration and tubular reabsorption. The abnormally increased proteins include free hemoglobin, myoglobin, lysozyme, and periplasmic protein, etc. The urinary protein characterization is mostly 1+ to 2+. It is commonly seen in multiple myeloma, etc. 5.Tissue proteinuria This kind of proteinuria originates from the protein produced by the metabolism of renal tubules, decomposed by tissue destruction, and secreted by the urinary system stimulated by inflammation or drugs, which enters the urine. It is mainly T-H glycoprotein, physiologically about 20mg/d, urinary protein qualitative ±~1+, quantitative 0.5~1.0g/24h. II. Pseudoproteinuria Due to some reasons, one of the routine urine tests is positive for protein. Pseudoproteinuria generally occurs in the following cases, and if any of these causes proteinuria, an in-depth examination is recommended. There are several types of pseudoproteinuria: ① Blood, pus, inflammatory or tumor secretions, menstrual blood, and leukorrhea are mixed in the urine, and the routine qualitative proteinuria test can be positive. After the urine is centrifuged and precipitated or filtered, the qualitative protein test will be significantly reduced or even turned negative; ②After the urine is left for a long time or cooled, salt crystals can be precipitated, making the urine white and cloudy, which can be easily mistaken for protein urine, but warming or adding a little acetic acid can turn the cloudy urine clear to help distinguish; ③Mixed with semen or Prostate fluid, or inflammatory secretions of the lower urinary tract, etc., the urine protein reaction may be positive. In this case, the patient has the manifestation of lower urinary tract or prostate disease, and the urine sediment can find sperm, more flat epithelial cells, etc., which can be distinguished; ④ lymphatic urine, which contains less protein, is not necessarily celiac; ⑤ some drugs such as rifampin and Sandozian, etc., when discharged from the urine, can make the urine cloudy similar to proteinuria, but the protein qualitative reaction is negative. The diet of proteinuria note 1, nephritis patients with large amounts of proteinuria, generally can be supplemented by diet, that nephritis patients can not eat food containing protein is wrong, one-sided, even for chronic nephritis developed to an advanced stage – the uremic phase of patients, also advocate to eat a high-quality low protein diet. 2, daily protein intake should be controlled at 0.6 to 0.8 g/kg body weight. Patients with uremia, during dialysis treatment, especially when on peritoneal dialysis, the amount of protein eaten daily should be increased to about 1.2 to 1.5 g/kg of body weight. In patients with nephrotic syndrome, a large amount of protein is lost in the urine, such as those with normal renal function, it is advocated to eat a high protein diet to correct hypoproteinemia, reduce edema and improve or enhance the body’s resistance. 3, if patients with nephritis develop azotemia, or early renal insufficiency, the intake of protein should be limited. Otherwise, it will accelerate the deterioration of renal function. In short, different dietary recipes should be used for different conditions. When a large amount of proteinuria appears in kidney disease patients, there is no need to be overly panic; when a small amount of proteinuria appears, the severity of the condition should not be overlooked, and it is better to diagnose the condition in time and develop a corresponding treatment plan for proteinuria. From the perspective of kidney pathological damage to completely restore kidney function and eliminate proteinuria.