Synopsis
Distinguish symptomatic catheter-associated urinary infection from expected bacteriuria, collect a meaningful sample, optimise catheter care and treat according to anatomical severity.
- Bacteriuria becomes common with catheter duration and does not by itself diagnose catheter-associated urinary infection.
- Require compatible urinary or systemic symptoms and actively assess catheter blockage, trauma, bladder spasm and non-urinary causes.
- Do not use urine dipsticks to diagnose infection in catheterised adults because leucocytes, blood and nitrite are frequently misleading.
Key red flags
Absent catheter drainage with a painful palpable bladder suggests acute retention or mechanical obstruction.
Bypassing, poor drainage, sediment, bladder distension, pain or spasm suggests kinking, encrustation, displacement or blockage needing immediate correction.
Investigation priorities
Identify kinking, disconnection, leakage, bladder distension or blockage before attributing poor drainage to infection.
Management branches
A catheterised adult has cloudy urine, a positive test, pain, fever or functional deterioration.
- Assess for new urinary symptoms, upper-tract signs and sepsis while seeking respiratory, skin, abdominal, neurological and medicine-related alternatives.
- Inspect the catheter and bladder, restore drainage and remove the device if its indication has ended.
Key medicines
Nitrofurantoin modified releaseGive 100 mg orally twice daily for seven days for lower catheter-associated UTI when eGFR is adequate and upper-tract or prostate involvement is excluded.
TrimethoprimGive 200 mg orally twice daily for seven days for lower catheter-associated UTI when resistance risk is low or susceptibility is known.