Recurrent urinary tract infections or cystitis or complicated urinary tract infections usually have three causes: 1. The bacterial virulence or drug-resistant bacterial infections need to be confirmed by bacteriological cultures, and if positive cultures can be obtained, sensitive antibiotics need to be selected for three consecutive days or two weeks or longer according to the results; intravenous antibiotics should be paid attention to prevent mycobacterial infections; Chinese medicine can be added for synergistic treatment, which may reduce the If the attack is accompanied by high fever or back pain, intravenous drip antibiotics should be given for two weeks after controlling bacteremia; attention should also be paid to the presence of specific strains of infection such as tuberculosis. Go to a regular hospital urological specialist infection clinic for examination and standardized treatment . 2, low resistance; the most common cause in the elderly is due to poor control of diabetes; there are other diseases due to long-term oral steroid hormones or taking some kind of immunosuppressant. 3.Urinary dysfunction. It is not uncommon in middle-aged and elderly people, and careful history taking can reveal that such patients are mostly accompanied by urinary difficulty or dyspareunia. When encountering such symptoms, it may be considered as complicated urinary tract infection, which requires urinary flow rate and residual urine volume measurement examination or further urodynamic examination. Recurrent urinary tract infections in those with dyspareunia can only reduce or eliminate the chance of recurrence of urinary tract infections if the cause of the dyspareunia is removed; the use of intravenous drip antibiotics and long-term oral antibiotics alone in such patients can only be temporarily effective and will soon recur.