The reasons why women are prone to urinary tract infections are mainly caused by the special structure of the female reproductive system, the fact that female vaginal secretions are also a better medium for the use of bacteria to multiply more easily, and the slow flow of urine to form a mild effusion. Urinary tract infection, also known as urinary tract infection, is an inflammation of the urinary tract caused by pathogens growing and multiplying in the urinary tract of the organism and invading the mucous membrane or tissue of the urinary tract. Bacteria are the most common pathogens, while fungi, viruses, and parasites can also cause infections. What is the differential diagnosis of slow urine flow? Urinary tract infections are generally divided into upper urinary tract infections and lower urinary tract infections. Urethral infections can be subdivided according to the route of bacterial invasion: bloody infections, upstream infections, and downstream infections. This is because the female urethra is straight and short, so bacteria can easily travel up to the bladder and cause infection. In addition, the external opening of the female urethra is very close to the vaginal opening and the anus, so it is easily contaminated by the bacteria excreted in the feces and the open channel. Clinically, lower urinary tract infections, namely cystitis, are common and frequent in older women, with an incidence 8-10 times higher than that of men, so prevention is important. Upper urinary tract infection refers to pyelonephritis, an infectious inflammation of the renal parenchyma and pelvis, which is caused by bacterial invasion of the kidney. Pyelonephritis is clinically divided into acute pyelonephritis and chronic pyelonephritis. Most acute pyelonephritis is caused by pathogenic bacteria reaching the kidney via the bladder and ureter, causing inflammation, mainly acute interstitial inflammation and varying degrees of necrosis of renal tubular epithelial cells. With regard to the definition of chronic pyelonephritis, most scholars now believe that this diagnosis has been too abusive in the past and that chronic pyelonephritis should be limited to those with clear inflammation, fibrosis and deformation of the renal pelvis and calyces. If this diagnostic criterion is used, the vast majority of chronic pyelonephritis is caused by an additional urinary tract infection on top of urinary tract obstruction, poor urinary flow, or bladder-ureteral reflux. In the absence of these conditions, urinary tract infections often do not cause severe chronic kidney disease. Therefore, acute and chronic pyelonephritis should be differentiated not by the length of its course or the number of recurrent episodes, but by the presence or absence of deformation of the pelvic calyces on imaging. Infections of the lower urinary tract are mainly urethritis and cystitis, with infectious inflammation confined to the urethra and bladder. Lower urinary tract infections are divided into cystitis and urethritis. Older women are prone to lower urinary tract infections because there are many predisposing factors, both congenital and acquired: 1, the female urethral orifice is adjacent to the vaginal orifice and the anus, and is easily contaminated by vaginitis secretions (vaginitis, cervicitis) and feces; 2, due to the decline in ovarian function, the level of estrogen in the body decreases, and the epithelium of the urethra, which is also affected by estrogen, atrophies and thins, and its defenses are greatly weakened, making it easy for bacteria to invade 3. the female urethra is born straight, wide and short, with a length of only 3 to 4 cm, once invaded by bacteria, it is easy to enter the bladder from the urethra upstream. 4. as we age, the tissue structure and function of the bladder changes, and often urination is not smooth and incomplete. Residual urine is a good culture medium for bacterial growth and reproduction. Causes.