Diagnosis of recurrent UTI in nonpregnant adults

Chen, 2023Naber, 2020Pat, 2022Wynn, 2024Zare, 2022

For recurrent urinary tract infection (UTI) during pregnancy, see Recurrent UTI and bacteriuria in pregnancy.

Recurrent UTI in nonpregnant adults is defined as 2 or more episodes of symptomatic infection (acute cystitis or pyelonephritis) within 6 months or 3 or more episodes within 12 months, where at least one episode has been confirmed by midstream urine sample microscopy and culture (see Interpreting microbiological investigations for acute cystitis in adults)Bonkat, 2024Chen, 2023Kwok, 2022National Institute for Health and Care Excellence (NICE), October 2018. Recurrent pyuria has little clinical meaning in isolation. Recurrent asymptomatic bacteriuria is not recurrent UTI and does not require antibiotic therapy, except in specific circumstances – see Asymptomatic bacteriuria in nonpregnant adults.

For nonpregnant adults with recurrent symptomatic UTI, obtain a midstream urine sample for microscopy, culture and susceptibility testingBonkat, 2024Kwok, 2022Zare, 2022.

Always take a history and examine the patient. Consider:

• alternative diagnoses (eg sexually transmissible infections [STIs], vulvovaginitis)
• a broader range of pathogens if the epidemiology is suggestive (eg genitourinary schistosomiasis, tuberculosis)
• conditions that may impair bladder emptying and predispose to recurrent UTI (eg vaginal prolapse, benign prostatic hyperplasia [BPH]); assessment of post-void residual urine volumes and urodynamic studies may be helpful.

For males with recurrent UTI, urological evaluation to assess for prostatic disease (eg chronic bacterial prostatitis) should be consideredNational Institute for Health and Care Excellence (NICE), October 2018.

For most females¹ with recurrent cystitis, routine cystoscopy and computed tomography (CT) scans have limited valueBonkat, 2024Kwok, 2022Zare, 2022.

Further investigation with cystoscopy and/or imaging is recommended for adults with relapsing infection with an identical pathogen (same bacterial species and antibiotic susceptibility pattern) to look for a source of infection (eg kidney and ureteric stones; renal abscess; prostatic abscess).

Urinary tract imaging is recommended for adults with a second episode of pyelonephritis within 12 monthsKwok, 2022.

Patients with symptoms of recurrent UTI who do not have urine cultures consistent with infection and in whom alternative diagnoses (eg STI, vulvovaginitis) have been excluded, should be referred to a urologist for investigation.

For patients with ongoing UTI symptoms following appropriate antibiotic therapy, seek expert urology advice.