CBSE Class 10 Answered
The urine is normally sterile. An infection occurs when bacteria get into the urine and begin to grow. The infection usually starts at the opening of the urethra where the urine leaves the body and moves upward into the urinary tract. In most cases, the culprit is a type of bacteria called Escherichia coli, better know as E. coli. These bacteria normally live in the bowel (colon) and around the anus. These bacteria can move from the area around the anus to the opening of the urethra. The two most common causes of this are poor hygiene and sexual intercourse.
The bacteria can travel up the urethra to the bladder, where they can grow and cause an infection. The infection can spread further as the bacteria move up from the bladder via the ureters. If they reach the kidney, they can cause a kidney infection (pyelonephritis), which can become a very serious condition if not treated promptly.
The following people are at increased risk of urinary tract infection:
- People with conditions that block (obstruct) the urinary tract, such as kidney stones
- People with medical conditions that cause incomplete bladder emptying (for example, spinal cord injury or bladder decompensation after menopause)
People with suppressed immune systems - Women who are sexually active:
- Women who use a diaphragm for birth control
- Men with an enlarged prostate.