The commonest causes of UTI are bacteria that harbor in the digestive system. These bacteria enter the urethra and migrate up to the bladder, where multiplication takes place.
The defense mechanism of urinary system helps to resist the bacteria but sometimes it fails and causes bacteria to grow leading to UTI.
Commonly, UTIs occur mainly in women and children affecting the bladder and urethra.
The causes of UTI are as follows:
- Infection of bladder (Cystitis): Several pathogens are known to cause UTI but the common bacteria, E. Coli, is responsible for 80-85% cases of the disease. Poor hygiene and sexual intercourse increase the chances of acquiring the infection.
- Infection of urethra (Urethritis): This is mainly seen when bacteria enter the urethra from anus. Since the urethra is closer to vagina in females, sexually transmitted organisms like Herpes, Chlamydia can also figure among the causes of UTI.
- Incomplete emptying of bladder: If you try to hold urine for longer time, and then try to urinate, it causes a stretch or pressure on bladder muscles which later become weakened and cause incomplete emptying of bladder, increasing the risk of UTI.