The Chicken-Egg Dilemma: Legionnaires' Disease and Retrograde Contamination of Dental Unit Waterlines.

the Centers for Disease Control and Prevention/ National Healthcare Safety Network, are primarily designed for surveillance purposes, and only patients with KPC-2-Kp bacteriuria who do not meet these criteria are thought to have urinary tract infection and receive treatment. The results presented here show that the outcomes of CRE bacteriuria/bacteremia are influenced by both the choice of antimicrobial treatment and the CRE isolate type. The selective pressure imposed by antibiotic usage has been strongly associated with the emergence of resistance, as observed in this study and in previous reports regarding polymyxins, tigecycline, and fosfomycin, which are considered “reappraised” therapeutic options to treat multidrug-resistant microorganisms. Unequivocally, endemic KPC-2-Kp has become quite more competitive than multidrug-resistant noncarbapenemase isolates that proved to be self-limited, with neither bacteremia case nor development of resistance observed in this study (Table 1); KPC-2-Kp is probably favored by the presence of a more robust resistance mechanism, such as the production of carbapenemase, although blaKPC-2 gene has not been associated with virulence by itself. In conclusion, KPC-2-Kp isolates presented with recurrent/ subsequent bacteriuria as the main urinary outcome and as such developed cases of bacteremia with a high 30-day mortality rate being observed. Increase in resistance rates was observed for all agents evaluated, possibly driven by previous use similar to prior observations for KPC-2-Kp recovered from surveillance rectal swab samples. These findings and the poor outcomes for KPC-2-Kp infection underscore the urgent need for better surveillance and stewardship programs to combat these antibiotic stains.