Urinary tract infection (UTI) is an infection in any part of the urinary system. Lower UTI affects the bladder (cystitis); upper UTI affects the ureters or kidneys (pyelonephritis).

UTI is more common in females.

Complicated UTI occurs when the urinary tract is abnormal, if a patient has a catheter (catheter-associated UTI), if the causative organisms are atypical, or if there are predisposing co-morbidities such as poorly controlled diabetes. Uncomplicated UTI is caused by typical organisms in people with a normal urinary tract and kidney function. Complicated UTI increases risk of persistent infection, treatment failure and recurrent infection (recurrent UTI).

Most UTIs can be easily treated with antibiotics, although recurrence is possible, particularly in women.

NICE CKS - Lower UTI in women

NICE CKS - Lower UTI in men

NICE CKS - Pyelonephritis (acute)

NICE CKS - UTI in children

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