Nephrotic syndrome is a group of symptomatic syndromes presenting with massive proteinuria, hypoproteinemia, hyperlipidemia and severe edema of unknown etiology, associated with infection, autoimmune abnormalities, and genetic basis. Most pathological types of nephrotic syndrome in small infants and children are mostly microscopic lesions, sensitive to hormone therapy, but prone to recurrent relapses. With the current standard course of treatment, nearly half of children still relapse in the first year of treatment, leading to return to hospitalization, increased medication and medication time, and increased treatment costs. Why exactly does nephrotic syndrome relapse? There are many reasons: 1. Infection: It is the most common reason, because the child’s disease and immunosuppressive treatment, so that the child’s own immune function, prone to various bacterial or viral infections of the respiratory tract, urinary tract, intestinal tract, etc., can aggravate proteinuria and oliguria, swelling, resulting in recurrence of nephropathy, the child often does not have serious symptoms when infected like ordinary children (such as fever, cough, urinary urgency and painful urination, etc.), which is also difficult for doctors to 2, allergies: the relapse of some children with nephrotic syndrome, related to the season, with more in the spring and autumn, children often show with runny sneeze, rash and other symptoms. Allergens causing allergy can be dust mites, pollen, food, bacteria and viruses, etc.; 3. Insufficient dosage of immunosuppressive drugs: In the process of hormone reduction, or immunosuppressive drug reduction, because the medication cannot control the immune imbalance state of the child, which can lead to recurrent infection and allergy symptoms persisting in the child, and the nephrotic state cannot be relieved. 4. Inhibited state of adrenal cortical function, 5. Low thyroid function, etc. For these reasons, during the recurrence of nephrotic syndrome, attention should be paid to the necessary examination and anti-infection and anti-allergy treatment for the above-mentioned etiologies. Pay attention to the monitoring of immunosuppressant blood concentration and adrenal cortical function, and adjust the medication according to the examination results in time to achieve remission of nephropathy.