The CBIC Certified Infection Control Exam Study Guide (6th edition) clearly states that the correct and recommended method for obtaining urine cultures in patients with an indwelling urinary catheter is to collect the specimen using aseptic technique from the catheter’s designated sampling (collection) port. This method minimizes the risk of contamination and provides the most accurate reflection of organisms present in the urinary tract.

Urine collected from the sampling port is obtained after disinfecting the port and aspirating urine with a sterile syringe. This approach maintains the integrity of the closed drainage system and reduces the introduction of microorganisms. Accurate culture collection is essential for correct diagnosis of catheter-associated urinary tract infection (CAUTI) and for distinguishing true infection from colonization or contamination.

Option B is incorrect because culturing the catheter tip is not recommended for diagnosing CAUTI; it does not reliably represent urinary tract pathogens and may reflect biofilm colonization. Option C is inappropriate because disconnecting the catheter from the drainage tubing breaks the closed system and increases infection risk. Option D is incorrect because urine from the drainage bag is often contaminated and does not accurately represent bladder urine.

For CIC® exam preparation, it is critical to recognize that aseptic aspiration from the catheter sampling port is the standard of care for urine culture collection in catheterized patients and is a core infection prevention principle related to CAUTI surveillance and diagnosis.

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