Cystitis usually occurs when the urethra and bladder, which are normally sterile (microbe free) become infected by bacteria – the area becomes irritated and inflamed.

Cystitis is a fairly common lower urinary tract infection, which affects people of both sexes and all ages. It is more common among females than males.

Approximately 80% of all urinary tract infections are caused by Escherichia coli. These bacteria form part of the healthy intestinal flora. However, virulent types may get into the bladder via the urethra and cause urinary tract infections. Urinary tract infections account for a large proportion of hospital-acquired infections, especially among patients using urinary catheters.

There are many possible causes of cystitis:

• When women insert a tampon there is a slight risk of bacteria entering via the urethra.
• When a urinary catheter is changed there may be damage to the area.
• There is a higher incidence of cystitis among women who use the diaphragm for contraception, compared to sexually active women who don’t.
• The patient does not empty his/her bladder completely, creating an environment for bacteria to multiply in the bladder. This is fairly common among pregnant women, and also men whose prostates are enlarged.
• Sexually active women have a higher risk of bacteria entering via the urethra.
• Part of the urinary system may be blocked.
• Other bladder or kidney problems.
• Frequent and/or vigorous sex increases the chances of physical damage or bruising, which in turn makes the likelihood of cystitis developing higher.
• During the menopause women produce less mucus in the vaginal area. This mucus stops the bacteria from multiplying. Women onHRT (hormone replacement therapy) have a lower risk of developing cystitis compared to menopausal women not on HRT.
• During the menopause the lining of a woman’s urethra gets thinner as her levels of estrogen drop. The thinner the lining becomes, the higher the chances are of infection and damage.
• A woman’s urethra opening is much nearer the anus than a man’s. Consequently, there is a higher risk of bacteria entering the urethra from the anus.