Introduction: In 2013, the Center for Disease Control (CDC) designated methicillin-resistant Staphylococcus aureus (MRSA) as a serious threat. In addition to its intrinsic virulence, MRSA has become resistant to numer...Introduction: In 2013, the Center for Disease Control (CDC) designated methicillin-resistant Staphylococcus aureus (MRSA) as a serious threat. In addition to its intrinsic virulence, MRSA has become resistant to numerous antibacterial agents. In many instances, mupirocin is used empirically to decolonize patients harboring MRSA to decrease the possibility of progression to disease. In vitro susceptibility information is critical to identify patients who would benefit from use of mupirocin for decolonization and treatment of infections caused by MRSA. Methods: One-hundred and sixty-three recent MRSA single patient clinical isolates were collected from the Clinical Microbiology Laboratory. In-vitro susceptibility testing was performed using E-test methodology for tigecycline, ceftaroline, daptomycin, vancomycin, linezolid, and mupirocin. Results: Of the 163 MRSA isolates tested, >99% demonstrated susceptibility to tigecycline, ceftaroline, daptomycin, vancomycin, and linezolid. Seventy (43%) had vancomycin MICs ≥ 1.5 μg/ml, twenty-four isolates (15%) were resistant to mupirocin, and three appeared to express mupirocin hetero-resistance. Conclusion: While antibiotic susceptibility to mupirocin is not routinely performed in clinical microbiology laboratories, the level of resistance to mupirocin identified in this surveillance study suggests that susceptibility testing should be added to routine MRSA panels.展开更多
A surveillance study was undertaken to identify prominent β-lactamase encoding genes in 131 carbapenem non-susceptible gram-negative clinical isolates at a New York City community hospital. KPC carbapenemases were de...A surveillance study was undertaken to identify prominent β-lactamase encoding genes in 131 carbapenem non-susceptible gram-negative clinical isolates at a New York City community hospital. KPC carbapenemases were detected in 89% of Enterobacteriaceae as well as additional TEM, SHV, and CTX-M class A enzymes. OXA-23 and OXA-24 were the prevalent class D carbapenemases identified in Acinetobacter species. One OXA-23 in M. morganii and one OXA-48 in K. pneumoniae were also identified. Among class C β-lactamases CMY, ACT/MIR, DHA, and FOX were detected. The in vitro activity of ceftazidime-avibactam by E-test methodology was tested with minimal inhibitory concentrations (MIC) of ≤3 μg/ml for 97.8% of all Enterobacteriaceae, MIC<sub>50/90</sub> of 16/>256 μg/ml for carbapenem non-susceptible Acinetobacter, and 3/6 μg/ml for carbapenem non-susceptible Pseudomonas aeruginosa. Periodic surveillance of isolates to characterize current and emerging β-lactamase genotypes present in local isolates may help identify outbreak situations, provide assistance to infection control and antibiotic stewardship programs, and potentially improve patient outcomes.展开更多
文摘Introduction: In 2013, the Center for Disease Control (CDC) designated methicillin-resistant Staphylococcus aureus (MRSA) as a serious threat. In addition to its intrinsic virulence, MRSA has become resistant to numerous antibacterial agents. In many instances, mupirocin is used empirically to decolonize patients harboring MRSA to decrease the possibility of progression to disease. In vitro susceptibility information is critical to identify patients who would benefit from use of mupirocin for decolonization and treatment of infections caused by MRSA. Methods: One-hundred and sixty-three recent MRSA single patient clinical isolates were collected from the Clinical Microbiology Laboratory. In-vitro susceptibility testing was performed using E-test methodology for tigecycline, ceftaroline, daptomycin, vancomycin, linezolid, and mupirocin. Results: Of the 163 MRSA isolates tested, >99% demonstrated susceptibility to tigecycline, ceftaroline, daptomycin, vancomycin, and linezolid. Seventy (43%) had vancomycin MICs ≥ 1.5 μg/ml, twenty-four isolates (15%) were resistant to mupirocin, and three appeared to express mupirocin hetero-resistance. Conclusion: While antibiotic susceptibility to mupirocin is not routinely performed in clinical microbiology laboratories, the level of resistance to mupirocin identified in this surveillance study suggests that susceptibility testing should be added to routine MRSA panels.
文摘A surveillance study was undertaken to identify prominent β-lactamase encoding genes in 131 carbapenem non-susceptible gram-negative clinical isolates at a New York City community hospital. KPC carbapenemases were detected in 89% of Enterobacteriaceae as well as additional TEM, SHV, and CTX-M class A enzymes. OXA-23 and OXA-24 were the prevalent class D carbapenemases identified in Acinetobacter species. One OXA-23 in M. morganii and one OXA-48 in K. pneumoniae were also identified. Among class C β-lactamases CMY, ACT/MIR, DHA, and FOX were detected. The in vitro activity of ceftazidime-avibactam by E-test methodology was tested with minimal inhibitory concentrations (MIC) of ≤3 μg/ml for 97.8% of all Enterobacteriaceae, MIC<sub>50/90</sub> of 16/>256 μg/ml for carbapenem non-susceptible Acinetobacter, and 3/6 μg/ml for carbapenem non-susceptible Pseudomonas aeruginosa. Periodic surveillance of isolates to characterize current and emerging β-lactamase genotypes present in local isolates may help identify outbreak situations, provide assistance to infection control and antibiotic stewardship programs, and potentially improve patient outcomes.
