Antibacterial resistance of community-acquired respiratory tract pathogens recovered from patients in Latin America: results from the PROTEKT surveillance study (1999-2000)

protekt (prospective resistant organism tracking and epidemiology for the ketolide telithromycin) is a global surveillance study established in 1999 to monitor antibacterial resistance of respiratory tract organisms. thirteen centers from argentina, brazil and mexico participat ed during 1999-2000; they collected 1,806 isolates (streptococcus pneumoniae 518, haemophilus influenzae 520, moraxella catarrhalis 140, staphylococcus aureus 351, s. pyogenes 277). overall, 218 (42.1%) of the s. pneumoniae isolates had reduced susceptibility to penicillin, 79 (15.3%) were penicillin-resistant and 79 (15.3%) were erythromycin-resistant. mexico had the highest prevalence of penicillin (76.5%) and erythromycin (31.2%) resistance. of 77 erythromycin-resistant s. pneumoniae tested for resistance genotype, 43 possessed mef(a), 33 possessed erm(b) and 1 possessed both erm(b) and mef(a) mechanism. all s. pneumoniae isolates were fully susceptible to telithromycin, linezolid, teicoplanin and vancomycin. among h. influenzae isolates, 88 (16.9%) produced b-lactamase, ranging from 11% (brazil) to 24.5% (mexico). among m. catarrhalis isolates, 138 (98.6%) produced b-lactamase. twenty-four (8.7%) of the s. pyogenes isolates were erythromycin-resistant; resistance being attributable to mefa (n=18), ermtr (n=5) and ermb (n=1). all h. influenzae, m. catarrhalis and s. pyogenes were fully susceptible to telithromycin. methicillin resistance was found in 26.5% of the s. aureus isolates (argentina 15%; mexico 20%; brazil 31.3%). telithromycin was effective against 97.7% of methicillin-susceptible isolates. protekt confirms that antibacterial resistance is an emerging problem in latin america. the previously reported high levels of pneumococcal resistance to the b-lactam and macrolides were exceeded. new agents that do not induce resistance or that exert low selective pressure, e.g. telithromycin, are essential to safeguard future antibacterial efficacy.