Define the catheter-associated UTI.
Catheter-associated UTI (CAUTI): symptomatic UTI occurring in a patient with an indwelling urinary catheter OR within 48 hours after removal of a urinary catheter
Catheter-associated asymptomatic bacteriuria (CAASB): bacteriuria (≥ 105CFU/mL) without symptoms in a patient with an indwelling urinary catheter OR within 48 hours after removal of a urinary catheter
Describe the microbiology and clinical features.
Causative organisms are likely to have antibiotic resistance.
In patients with long-term catheterization (≥ 30 days), UTIs are typically polymicrobial.
Infection is commonly asymptomatic or presents with atypical symptoms.
Possible symptoms include fever, pelvic or flank pain, hematuria, altered mental status, and lethargy.
Catheter obstruction may result from colonization with urease-producing organisms, especially Proteus spp.
A urine culture, ideally obtained prior to antibiotic treatment, is always required to diagnose CAUTI.
Indications: features consistent with potential infection
Specimen collection: ideally from the sampling port of a newly inserted device using aseptic technique
Significant bacteriuria thresholds in catheterized patients 
CAASB: ≥ 105CFU/mL without symptoms
CAUTI: ≥ 103CFU/mL with symptoms of UTI
Pyuria is usually present but is not diagnostic of CAUTI in isolation.
Describe the treatment.
Catheter removal or replacement
Remove if no longer necessary.
Replace if still necessary and present for > 2 weeks.
Guided by culture results and local resistance patterns
See “Antibiotic treatment of complicated lower UTIs” and “Empiric antibiotic therapy of complicated pyelonephritis” for potential empiric regimens.
Duration: typically 7–14 days depending on the resolution of symptoms