Urinary tract infection

Urinary tract infection is one of the most common infections to affect humans. Uncomplicated infections occur most commonly in otherwise healthy women when uropathogenic bacteria, usually Escherichia coli, enter the bladder and overcome host innate immunity. Complicated infections occur in patients with an anatomical or functional abnormality of the urinary tract. Diagnosis is made on the basis of symptoms and diagnostic precision is improved by urinalysis. Urine culture is important in patients with severe, recurrent or complicated infection and when diagnosis is uncertain, for example children and the elderly. Most women with symptoms that resolve quickly do not require further investigation, but imaging of the renal tract, functional testing and cystoscopy should be considered in children, men and patients with recurrent or severe infection. Empirical antibiotic treatment started on the basis of symptoms and directed by urinalysis is suitable for uncomplicated cystitis but should be altered based on culture results for more severe infections. Three days of antibiotic treatment is usually sufficient for uncomplicated cystitis in women. Long-term or post-coital antibiotics are effective treatments for patients with recurrent infection.