RESUMO
We report a case of infective endocarditis (IE) caused by ceftaroline-resistant, daptomycin-tolerant, and heterogeneous vancomycin-intermediate methicillin-resistant S. aureus (MRSA). Resistance to ceftaroline emerged in the absence of drug exposure, and the E447K substitution in the active site of PBP2a previously associated with ceftaroline resistance was identified. Additionally, we present evidence of patient-to-patient transmission of the strain within the same unit. This case illustrates the difficulties in treating MRSA IE in the setting of a multidrug-resistant phenotype.
Assuntos
Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Daptomicina/uso terapêutico , Farmacorresistência Bacteriana Múltipla/genética , Endocardite Bacteriana/tratamento farmacológico , Proteínas de Ligação às Penicilinas/genética , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina/uso terapêutico , Adulto , Substituição de Aminoácidos , Cefalosporinas/uso terapêutico , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Infecção Hospitalar/patologia , Quimioterapia Combinada , Endocardite Bacteriana/microbiologia , Endocardite Bacteriana/patologia , Expressão Gênica , Humanos , Masculino , Meticilina/uso terapêutico , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/patologia , CeftarolinaRESUMO
We performed a nested case-control study (ratio of 1:4) on the emergence of tigecycline-resistant multidrug-resistant Klebsiella pneumoniae (TR-MDRKP) isolates among patients who initially presented with a tigecycline-susceptible MDRKP isolate. Out of 260 patients, 24 (9%) had a subsequent clinical culture positive for a TR-MDRKP isolate within the 90-day follow-up period. On logistic regression analyses, receipt of tigecycline (adjusted odds ratio [OR], 5.06; 95% confidence interval [CI], 1.80 to 14.23; P = 0.002) was the only independent predictor of subsequent isolation of a TR strain.