Multicentre assessment of linezolid antimicrobial activity and spectrum in Europe: report from the Zyvox® antimicrobial potency study (ZAPS-Europe)

Abstract

Compared to the North American component of this study, there was substantially less vancomycin resistance among E. faecium isolates (Europe 3.0% vs. North America 63.4%). While the occurrence of penicillin-resistant S. pneumoniae in Europe and North America was similar (25.1% vs. 29.7%), the recovery of high-level penicillin-resistant strains was nearly three-fold higher in North America (4.9% vs. 13.2%). Only linezolid was universally active against all the tested Gram-positive isolates at </=4 mg/L.

Trends in linezolid susceptibility patterns: report from the 2002–2003 worldwide Zyvox Annual Appraisal of Potency and Spectrum (ZAAPS) Program

“…Table 2 provides a summary of the organisms tested against linezolid and the comparator antimicrobial agents. The activity of linezolid against staphylococci proved to be exceptional in 2003 and nearly identical to that found in the 2002 ZAAPS Program (Table 3) [13] and the pre-marketing ZAPS data [14][15][16][17][18]. The linezolid MIC 90 and modal MIC for S. aureus and CoNS were 2 and 1 mg/L, respectively, with all isolates categorised as susceptible [20].…”

“…and CoNS isolates were two-fold lower (MIC 90 , 1 mg/L) than either S. aureus or the enterococci MIC 90 (2 mg/L). This relationship has not changed from the initial pre-marketing surveillance efforts performed for this oxazolidinone [12][13][14][15][16][17][18].…”

“…In 2003, over 8000 isolates were tested. In this report, the results for both years were compared with the pre-marketing Zyvox ® Antimicrobial Potency Study (ZAPS) reported from North America [14,15], Latin America [16], Europe [17] and the Western Pacific [18].…”

Oxazolidinone susceptibility patterns for 2005: International Report from the Zyvox® Annual Appraisal of Potency and Spectrum Study

“…Of particular interest, linezolid exhibited excellent activity against DRSP, S. pyogenes, S. agalactiae, and viridans group streptococci. Other linezolid surveillance studies have consistently demonstrated similar activity [4,[10][11][12][13][14][15][16][17][18], including several from Europe [14][15][16][17]. While among Gram-positive organism infections vancomycin may still be a preferred drug for treatment, emerging resistance in enterococci and S. aureus has seriously compromised this agent in some geographic regions.…”

Linezolid-Resistant Enterococcus faecalis Isolated from a Cord Blood Transplant Recipient

“…In the laboratory, strains of linezolid-resistant enterococci have been generated by serial passage of clinical VRE isolates by using doubling dilutions of linezolid; linezolid resistance was associated with mutations in the domain V region of the 23S rRNA gene (21). Clinical infections by linezolid-resistant Enterococcus species have been reported at individual centers (2, 9, 11, 13) but have been rare in the United States and internationally (3,4,6). The true frequency of linezolid-resistant enterococcal infections may be underestimated, because many laboratories do not routinely test enterococccal isolates for linezolid susceptibility.…”