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.
- Obtain urine before antibiotics from the sampling port using aseptic technique, or from a newly inserted catheter after change; never use the drainage bag.
- Remove the catheter when no longer needed; if it has been in place more than seven days and remains necessary, change it promptly without delaying antibiotics.
- Lower-tract symptoms may use a seven-day oral regimen; upper-tract or septic features require pyelonephritis or sepsis treatment.
- Do not give routine antibiotic prophylaxis to prevent infection during long-term catheter use or every catheter change.
- Review culture and response within 48 hours and investigate ongoing obstruction, encrustation, stones or an alternative source.
Key red flags
Absent catheter drainage with a painful palpable bladder suggests acute retention or mechanical obstruction.
Fever, rigors, loin pain or costovertebral-angle tenderness indicates possible upper urinary tract involvement.
Hypotension, tachypnoea, confusion, mottling or oliguria requires urgent sepsis assessment.
Visible haematuria with clots can obstruct the catheter and requires urgent urological assessment.
Persistent symptoms after catheter change and active therapy suggests stone, abscess, resistant infection or another source.
Bypassing, poor drainage, sediment, bladder distension, pain or spasm suggests kinking, encrustation, displacement or blockage needing immediate correction.
Loin pain, fever, rigors, vomiting or renal tenderness should be managed as catheter-associated pyelonephritis rather than lower infection.
Hypotension, confusion, tachypnoea, mottling or reduced urine output demands urgent systemic treatment while other sources are considered.
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.
- Do not use dipstick or isolated culture to diagnose infection; obtain a fresh culture only when symptoms make treatment plausible.
- Give observation without antibiotics for asymptomatic bacteriuria unless pregnancy or a specified urological-procedure indication applies.