What is a urinary tract infection?
A urinary tract infection (UTI) is an infection of the urinary system. The urinary system consists of the kidneys, the ureters, the bladder and the urethra.
When an infection affects the lower urinary tract (urethra or bladder), it may be called urethritis, or cystitis if it affects the bladder. When it affects the upper urinary tract (ureters or kidneys) it is called ureteritis, or pyelonephritis if it affects the kidneys.
What causes UTIs?
Most UTIs are caused by the spread of bacteria (eg, Escherichia coli) from digestive system — where they usually live and do not cause a problem — to the urethra (often via the anus). Once inside the urinary tract, these bacteria can multiply and cause an infection resulting in local irritation and inflammation.
For most people, a UTI is a one-off illness that resolves quickly and responds to treatment with antibiotics when necessary. However, for some people, UTIs are a recurrent (recurring) problem.
You are considered to have recurrent UTIs if you have either:
- 2 or more UTIs within 6 months, or
- 3 or more UTIs within 1 year.