Jamestown Canyon virus: seroprevalence in Connecticut.

Vol. 7, No. 5, September-October 2001 911 Emerging Infectious Diseases (blaPER-1 and blaVIM-2 ) had been detected separately among clinical isolates, underscores the possibility of the emergence of new threatening combinations of resistance determinants among nosocomial pathogens. In fact, the recruitment of similar resistance determinants within a single P. aeruginosa strain can determine a resistance phenotype to virtually all the available antipseudomonal beta-lactams, an occurrence that can be particularly dramatic when, as in the present case, resistance to beta-lactams is associated with resistance against aminoglycosides and fluoroquinolones. In this case, only piperacillin (which appears to be a relatively poor substrate for both enzymes [3,5]) retained moderate activity in vitro and, administered at high dosage in combination with tazobactam, was apparently effective in vivo. Should a similar resistance phenotype disseminate, it might have strategic implications for the development of new betalactamase inhibitors and for selection of beta-lactam compounds to associate wth inhibitors.