Disinfection of a probe used in ultrasound-guided prostate biopsy

Transrectal ultrasound (TRUS)-guided prostate biopsies are among the most common outpatient diagnostic procedures in urology clinics and carry the risk of introducing pathogens that may lead to infection.

To investigate the effectiveness of procedures for disinfecting a probe used in ultrasound-guided prostate biopsy.

The effectiveness of disinfection was determined by inoculating 10(7) colony forming units (cfu) of Pseudomonas aeruginosa at the following 3 sites on the probe: the interior lumen of the biopsy needle guide, the outside surface of the biopsy needle guide, and the interior lumen of the ultrasound probe where the needle guide passes through the transducer. Each site was investigated separately. After inoculation, the probe was immersed in 2% glutaraldehyde for 20 minutes and then assessed for the level of microbial contamination.

The results demonstrated that disinfection (ie, a reduction in bacterial load of greater than 7 log(10) cfu) could be achieved if the needle guide was removed from the probe. However, if the needle guide was left in the probe channel during immersion in 2% glutaraldehyde, disinfection was not achieved (ie, the reduction was approximately 1 log(10) cfu).

Recommendations for probe disinfection are provided and include disassembling the device and immersing the probe and the needle guide separately in a high-level disinfectant.