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

Abstract

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 participated during 1999-2000; they collected 1806 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 beta-lactamase, ranging from 11% (Brazil) to 24.5% (Mexico). Among M. catarrhalis isolates, 138 (98.6%) produced beta-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 beta-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.

Employing pharmacokinetic and pharmacodynamic principles to optimize antimicrobial treatment in the face of emerging resistance

“…Subsequent years (up to 2003) from the SENTRY studies have demonstrated no increases in penicillin non-susceptibility or high-level resistance in these countries (33). Similar observations were seen in other surveillance studies (11,56). Fluoroquinolone resistance, which has been increasing in Asia and Canada, remains less than 0.5% in Latin America.…”

Polyclonal dissemination of tetracycline resistance among Streptococcus pyogenes paediatric isolates from Brazil

“…However, great variability across different areas has been reported [5] and scarce data are available for GAS isolated in South America [6][7][8][9]. GAS tetracycline resistance is also reported in many countries and data from South America show a proportion of resistant isolates ranging from 8 to 70% [10][11][12][13]. None of these recent studies have analyzed the presence of the tetracycline resistance-conferring genes.…”

Streptococcus pneumoniae: sensibilidade a penicilina e moxifloxacina

“…(3,(13)(14)(15) Mendes et al also found a very low overall prevalence of resistance to fluoroquinolones in Latin America (0.8%), complete resistance to levofloxacin (MIC ≥ 8 µg/ mL) being observed in 1 isolate (0.4%) in Brazil and 3 (1.5%) in Mexico. (4) Moxifloxacin has greater activity against pneumococci because it has a higher affinity for DNA gyrase than do older generations of fluoroquinolones. It has been demonstrated that moxifloxacin less commonly selects for resistant strains, mainly because it is bulkier and less hydrophilic, exhibiting a decreased affinity for the efflux mechanism.…”

“…The highest proportion of fully resistant isolates was observed in Mexico City (24.1%), and it was relatively low in most centers in Brazil (8.1%). (4) However, in 2008, the Clinical Laboratory Standards Institute (CLSI) updated the penicillin susceptibility breakpoints for S. pneumoniae with new category definitions according to the clinical source of the isolates (meningitis and non-meningitis), based on pharmacokinetic and pharmacodynamic evidence. In recent studies in Brazil, (5) none of the evaluated strains was resistant to penicillin-i.e., with a minimum inhibitory concentration (MIC) ≥ 8 µg/mLwhen the updated CLSI standards were applied.…”