Nephritis is a group of kidney diseases with kidney injury, which can be classified into glomerulonephritis, interstitial nephritis, hereditary nephritis, pyelonephritis and so on according to clinical classification. 1. Glomerulonephritis: It is mainly divided into two categories: primary and secondary. Primary glomerulonephritis often has antecedent infections, such as acute tonsillitis or skin infections, and is commonly seen in acute glomerulonephritis, acute progressive glomerulonephritis, and chronic glomerulonephritis. Secondary glomerulonephritis is common in lupus nephritis caused by lupus erythematosus and allergic purpura nephritis caused by allergic purpura. 2. Interstitial nephritis: it can be divided into acute interstitial nephritis caused by pathogen infection or drugs, and chronic interstitial nephritis caused by nephrotoxicity. 3. Hereditary nephritis: mainly caused by gene mutation, with clinical manifestations such as hematuria, progressive renal failure, or hearing change or eye disease. 4. Pyelonephritis: Pyelonephritis refers to the inflammation of kidney and renal pelvis, which is mostly caused by bacterial infection, often accompanied by inflammation of lower urinary tract, such as frequent urination, urgency, painful urination and so on. If the patient found pyelonephritis, it is recommended to go to the regular hospital in time, improve the examination to clarify the cause of the disease, and then give targeted treatment or treatment under the guidance of the doctor.