MYSTIC program: summary of European data from 1997 to 2000

The Meropenem Yearly Susceptibility Test Information Collection (MYSTIC) Program is a global study providing in-vitro surveillance data on microbial susceptibility in centers that prescribe meropenem. This paper summarizes data on the activity of meropenem and five comparator agents against 13,793 clinical isolates from 31 centers in 10 European countries, 1997-2000. Meropenem and imipenem demonstrated broad-spectrum activity against the tested organisms, including beta-lactamase-producing strains that were co-resistant to quinolones and aminoglycosides. The carbapenems were active against the most frequently isolated pathogens including staphylococci (98-100% susceptible), Pseudomonas aeruginosa (65-82% susceptible) and Klebsiella pneumoniae (98-100% susceptible). Resistance to penicillins and cephalosporins was observed, particularly among Enterobacter species in Southern and Eastern Europe. Eastern Europe showed a high prevalence of AmpC beta-lactamase and extended-spectrum beta-lactamase-producing strains in Russia (2000); 47% and 28% of Enterobacteriaceae isolates were AmpC or ESBL-producers, respectively. There was no significant decrease in susceptibility to the carbapenems throughout the four-year period. Meropenem and imipenem appear to remain reliable options for the treatment of serious nosocomial infections.