Urinary tract infections (UTIs) are a common clinical condition and occur 9 times more frequently in women than in men. Most women will develop 2 or more urinary tract infections during their lifetime. In the United States, an estimated 4 to 6 million acute bacterial cystitis affects young women, with 25 to 30 percent of patients between the ages of 20 and 40. the incidence of UTIs increases with age by approximately 1 percent every 10 years, and approximately 10 percent of women over the age of 70 have UTIs. recurrent urinary tract infection (RUTI) is also In the Finnish study, 44% of women aged 17-82 years with E. coli cystitis recurred within the first year of initial infection, including 53% of those over 55 years of age and 36% of younger women. There is little epidemiological information on older women, and it is estimated that UTI occurs frequently in 10% to 15% of women over 60 years of age. 1. Pathogenesis The ability of bacteria to adhere to the urinary epithelium is the main cause of urinary tract infection. Most bacteria first settle in the rectum and then multiply around and distal to the urethra through the urethra into the bladder. Many genetic, biological and behavioral factors have been implicated. Local environmental changes in the vagina, such as pH and cervicovaginal antibodies, urine and bladder defense mechanisms play an important role in susceptible individuals. Host inflammation and immune response determine the outcome of clinical UTI. The current study found that the ability of E. coli with P-type hairs to multiply is a very risky causative factor for acute pyelonephritis. In contrast to pyelonephritis, little is known about the pathogenesis of cystitis, and the bacterial characteristics of E. coli causing cystitis are not known, nor are they distinguished from the causative strains that cause pyelonephritis. It is now known only that E. coli with erythrolysin, type I hairs and P hairs of prsGJ96 type are more commonly seen in acute cystitis than other E. coli. 2, causative factors 2.1, healthy premenopausal women Recent data show that sexual intercourse, diaphragm spermicide and repeated history of UTI are very risky causative factors. Recent use of antibiotics affects the vaginal flora and is likewise a causative factor in the recurrence of UTI. Frequency of sexual intercourse was the most risky causative factor in the multifactorial analysis. Others included spermicide use in the past year and having a new sexual partner, first UTI occurring before age 15, or a family history of UTI. Recurrent UTI is not associated with the way you urinate before or after intercourse, the frequency of urination, delayed urination habits, wiping patterns, douching, use of hot tubs, wearing tight leggings, or body mass index. 2.2. Healthy postmenopausal women Several studies have shown that estrogen deficiency (urogenital atrophy) is a risk factor for urinary tract infections, and Raz and Stamm demonstrated that intravaginal application of estrogen normalizes vaginal flora and reduces UTI recurrence. Postmenopausal UTI recurrence is also strongly associated with changes in bladder emptying mechanisms and physiological factors. 2.3, Recurrent UTI Patients with recurrent UTI have increased susceptibility to vaginal colonization with bacteria, and Stamey and Sexton demonstrated a 56% positive rate of vaginal culture for gram-negative rods in UTI patients compared to 24% in women without a history of UTI (p=0.0003). Colonization of the vagina by Enterococcus, Aspergillus chimaera, and Klebsiella was significantly higher in patients with recurrent UTI compared to controls. The mechanism by which bacteria adhere more readily to the urinary epithelium in a subset of patients with recurrent UTI is unknown and appears to be related to genetic factors. For example, the non-secretor phenotype and P1 phenotype are overexpressed in some girls and women with recurrent UTI and pyelonephritis, and analysis may suggest that the unique globular glycolipid receptor is selectively expressed after non-secretor uroepithelial binding to E. coli. Interleukin 8 receptor (IL8R) is another factor contributing to UTI recurrence. Interleukin 8 is an inflammatory cytokine that promotes the arrival of neutrophilic leukocytes to the urinary epithelium at the site of infection. It has been recently demonstrated that knockout mice lacking IL8R fail to clear the kidney of bacteria and eventually develop bacteriuria. In addition, preliminary analysis suggests that children with recurrent pyelonephritis have defective IL8R on neutrophils. Pelvic abnormalities may also contribute to UTI recurrence. The urethra-to-anus distance was found to be significantly shorter in patients with recurrent UTI compared to controls (4.8 and 5.0 cm, respectively; P=0.03). There were no differences in urethral length, residual urine, or voiding patterns (e.g., peak urinary flow rate, peak urinary flow time) between the case and control groups. It is hypothesized that pelvic anatomy plays an important role in the recurrence of urinary tract infection, especially among patients without exogenous risk factors. 3. Clinical diagnosis Collect a complete medical history, including history of urinary stones, diabetes mellitus and other urological diseases, history of urological surgery and instrumentation, etc. Detailed information about the patient’s previous infections, such as the frequency of infection, whether it is related to sexual life and contraceptive methods, etc. Previous bacterial culture results, treatment medications, and treatment effects are helpful in the analysis of recurrent urinary tract infections. Physical examination is performed according to the condition, with special attention to the pelvis and perineum to exclude urinary tract pathology, such as urethral meatus, stricture, prolapse, and vaginal lesions, and vaginal secretions are taken for examination if necessary. Clinical manifestations include, frequency, urgency, painful urination, difficulty in urination, pain in suprapubic area or lower abdomen, hematuria or cloudy urine. Laboratory diagnosis includes routine urinalysis and urine culture. Use the correct method to collect urine and tell the patient to hold the labia completely apart when collecting urine. For urine culture, the vulva should be washed with wet gauze, and then a midstream urine specimen should be taken. Disinfectants are not needed for washing because they can contaminate the specimen causing false negative results. Urinalysis for acute cystitis will show bacteriuria, pus, and hematuria. It is currently proposed that a urine culture with a colony count (CFU) of 102 CFU/ml or more in symptomatic patients confirms the diagnosis. Although urine cultures can determine drug susceptibility, the fact is that this is not done clinically and is not necessary. In many patients, treatment is completed before the urine culture results are available. Economic studies have shown that urine cultures for lower urinary tract infections increase costs by 40%, but only decrease the duration of symptoms by 10%. Pre-treatment urine cultures and sensitivity testing are mandatory in the following cases: recent antibiotic use, urinary tract infection symptoms for more than 7 d, age >65 years, diabetes mellitus or pregnancy. CT and ultrasound can rule out stones, obstructive disease, etc. Persistent hematuria should be followed by IVP, cystoscopy, etc. after the infection has cleared. Urinary tract infections should be differentiated from vaginitis, infections caused by sexually transmitted diseases, and urethral discomfort caused by non-inflammatory lesions. 4. Treatment of uncomplicated cystitis Uncomplicated cystitis (uncomplicated cystitis) occurs in women with normal urinary tract anatomy and function. The bacteria are usually sensitive to antibiotics and a short course of treatment is effective. In recent years, the course of treatment for acute cystitis has been greatly shortened and the traditional 7-14 d therapy has been replaced by a short course of 1 to 3 d treatment with similar efficacy and fewer side effects in the latter.