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Urinary Tract Infection (UTI)

Anatomy of the Urinary Tract

The urinary system comprises two kidneys in the abdominal region, responsible for urine production and waste elimination and the production of vital hormones. The bladder, a pelvic organ, stores the urine from the kidneys, holding approximately 350–500 millilitres. The urethra, a narrow tube, connects the bladder to the external environment. (Figure 1)


What is a Urinary Tract Infection (UTI)?

Urinary tract infections (UTIs) occur when microorganisms such as bacteria (most common), viruses, or fungi infect the urinary tract, which includes the kidneys, bladder, and urethra.

UTI symptoms include:

  • Urgent and frequent need to urinate
  • Minimal urine output despite frequent toilet visits
  • Painful urination at the opening of the urethra
  • Foul-smelling urine
  • Presence of blood in urine
  • Involuntary loss of urine in older individuals
  • Severe back or abdominal pain
  • Fever, nausea and vomiting
  • Appetite loss and lethargy, especially in older or non-communicative individuals

UTI statistics

  • Approximately 40% of women will experience a UTI, with 4% of young adult women in Singapore affected.
  • Adult women are 30 times more likely than men to develop a UTI, with 50% experiencing at least one episode during their lifetime.
  • One in three women experiences their first UTI by the age of 24.
  • Singapore's Ministry of Health reports that 4,144 patients were admitted to private and government hospitals between 1 January 2015 to 31 December 2015, with an average stay of 2–4.8 days.
What causes UTI?

UTIs can arise from various factors:

  • Host factors: Individuals with abnormal urinary anatomy or functional issues are more susceptible to infections. Those with compromised immune systems (e.g., diabetes) are at higher risk.
  • Pathogenic factors: Certain microorganisms have evolved to effectively  invade the urinary tract.
  • Environmental factors: Activities like sexual intercourse or the use of spermicides can increase susceptibility to infection in certain individuals.
What is recurrent UTI?

Recurrent UTIs are typically defined as more than two episodes of UTI within six months or more than three episodes within a year, confirmed by urine culture. UTIs can manifest as cystitis (involving the bladder) or pyelonephritis (involving the kidneys) and are classified as either complicated or uncomplicated.

Uncomplicated UTIs occur sporadically in healthy individuals, while complicated UTIs are associated with urinary tract abnormalities or underlying pathologies, increasing the risk of infection or treatment failure.

For recurrent UTIs, consultation with a family doctor or specialist is advised.

What are the services and treatments available for UTI?

Click here for more information on services and treatments available for UTI.

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