Cystitis is a type of urinary tract infection, and urinary tract infection is a rather general category, all parts of the urinary tract infection can be collectively called urinary tract infection, it includes kidney infection, renal pelvis infection, ureter infection, bladder infection, urethra infection or prostate infection, etc., all belong to the urinary tract infection. Therefore, cystitis is a specific manifestation of urinary tract infection, mainly because the bladder mucosa has an acute inflammatory reaction, resulting in mucosal congestion and edema, causing a series of symptoms such as frequent urination, urinary urgency, painful urination, and a sense of incomplete urination. If cystitis is not effectively controlled, it can also turn into other types of infections, such as inflammation of the ureter or infection of the renal pelvis, causing back pain with frequent urination, urinary urgency, and elevated body temperature. If the infection is not effectively treated for a long time, it may even develop into septic infection or infectious shock, in which case the patient may experience chills, high fever or lowered blood pressure.