Appropriate sampling sites for the surveillance of multidrug-resistant Pseudomonas aeruginosa colonization

This study aimed at evaluating the effectiveness of testing multiple samples (urine, stool, and pharyngeal swabs) for accurate screening of multidrug-resistant (MDR) Pseudomonas aeruginosa. Of a total of 641 patients, 16 (2.5%) were confirmed for MDR P. aeruginosa carriage at any site (urine and/or stool and/or pharyngeal swab). Notably, of the 3 sample sites, urine culture had the highest rate of positive surveillance for MDR P. aeruginosa. Seven (43.8%) of the 16 cases of MDR P. aeruginosa were detected by urine culture alone. Eleven (91.7%) of the 12 MDR P. aeruginosa carriers detected by urine culture had an indwelling urinary catheter. Our data suggest that urine culture was the most effective in detecting MDR P. aeruginosa carriage, particularly for patients with an indwelling urinary catheter. However, sample cultures from all 3 sites increased the detection rate of MDR P. aeruginosa carriage. Therefore, we recommend the use of a urine culture in combination with either a stool and/or a pharyngeal swab culture to increase the accuracy of MDR P. aeruginosa carriage detection.