Nephrotic syndrome is a clinical syndrome caused by increased permeability of the glomerular filtration membrane, resulting in the loss of large amounts of plasma albumin from the urine. It has four major features: massive proteinuria (qualitative >+++, 24hr quantification >50mg/kg); ‘hypoproteinemia (plasma albumin 5.72mmol/L);’ and varying degrees of edema. Various primary, secondary, congenital or hereditary glomerular diseases can cause this disease, but the vast majority (more than 90%) of the pediatric period is primary. 1, clinical typing (1) pure type Only those with the above four characteristics. (2) Nephrolithiasis type In addition to the above conditions, those with one or more of the following four: hematuria: 3 centrifugal urine tests within 2 weeks, red blood cells >10/HPF; ‘recurrent or persistent hypertension, 317.3/12.0kPa in school-age children and >16.0/10.7kPa in preschool children, and exclude those due to corticosteroids;ƒ Persistent azotemia, urea nitrogen “10.7 mmol/L, and exclude those who are due to blood volume deficiency; ƒ Recurrent reduction of total blood complement or C3. 2. Pathological typing The common pathological types are microscopic lesions (MCD) and non-microscopic lesions, the latter including focal segmental glomerulosclerosis (FSGS), mesangial proliferative nephritis (MsPGN), membranous nephropathy (MGN) and membranoproliferative nephritis (MPGN). In children, MCD is common, followed by FSGS and mild to moderate MsPGN. MGN is rare in pediatrics in primary cases, accounting for only 1 to 2%, and the vast majority are secondary, especially hepatitis B virus-associated nephritis. MPGN is a more serious type of pathology and requires early and timely diagnosis and treatment.