The clinical manifestations of interstitial nephritis are related to the etiology, condition and other factors. Acute interstitial nephritis and chronic interstitial nephritis can be seen. 1. Acute interstitial nephritis: Infection and drug-induced acute interstitial nephritis is often accompanied by low back pain. Allergic acute interstitial nephritis may be accompanied by maculopapular rash, fever and eosinophilia. Urinalysis in most patients shows mild to moderate proteinuria (less than 2 g/d). Microscopic hematuria and aseptic leukocyturia are predominant, and carnal hematuria is rare. 2. Chronic interstitial nephritis: proteinuria (usually <2g/d), microscopic hematuria, pyuria and tubular pattern are typical manifestations, but most of them start insidiously. Early stage is dominated by renal tubular dysfunction, such as the appearance of low specific gravity urine, urine increase, etc., and late stage appears the full manifestation of renal failure. Patients with interstitial nephritis are advised to go to regular hospitals in time and standardize the treatment under the guidance of doctors.