RESUMO
We conducted a retrospective study of 17 transplant recipients with carbapenem-resistant Klebsiella pneumoniae bacteremia, and described epidemiology, clinical characteristics and strain genotypes. Eighty-eight percent (15/17) of patients were liver or intestinal transplant recipients. Outcomes were death due to septic shock (18%), cure (24%) and persistent (>7 days) or recurrent bacteremia (29% each). Thirty- and 90-day mortality was 18% and 47%, respectively. Patients who were cured received at least one active antimicrobial agent and underwent source control interventions. Forty-one percent (7/17) of patients had intra-abdominal infections; all except one developed persistent/recurrent bacteremia despite drainage. Two patients tolerated persistent bacteremia for >300 days. All patients except one were infected with sequence type 258 (ST258), K. pneumoniae carbapenemase (KPC)-2-producing strains harboring a mutant ompK35 porin gene; the exception was infected with an ST37, KPC-3-producing strain. Seventy-one percent (12/17) of patients were infected with ST258 ompK36 mutant strains. In two patients, persistent bacteremia was caused by two strains with different ompK36 genotypes. Three ompK36 mutations were associated with significantly higher carbapenem minimum inhibitory concentrations than wild-type ompK36. Pulse-field gel electrophoresis identified a single ST258 lineage; serial strains from individual patients were indistinguishable. In conclusion, KPC-K. pneumoniae bacteremia exhibited highly diverse clinical courses following transplantation, and was caused by clonal ST258 strains with different ompK36 genotypes.
Assuntos
Bacteriemia/epidemiologia , Carbapenêmicos/farmacologia , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/genética , Transplante de Órgãos , Resistência beta-Lactâmica/genética , Adulto , Idoso , Antibacterianos/uso terapêutico , Bacteriemia/microbiologia , DNA Bacteriano/genética , Feminino , Seguimentos , Humanos , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/mortalidade , Klebsiella pneumoniae/isolamento & purificação , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de SobrevidaRESUMO
A real-time PCR assay was developed based on a 181-bp fragment of the recently cloned per gene, including an internal amplification control (124 bp), for the detection of Yersinia enterocolitica O:9 (Ye O:9). The validation included 48 Ye O:9, 33 Y. enterocolitica non-O:9 and 35 other closely-related bacterial strains, containing per gene homologies. The assay was specific for the Ye O:9 tested, the detection limit was 1-10 genome copies of purified DNA and amplification efficiency was between 90.5-103%, indicating a linear regression throughout the detection window.
Assuntos
Carboidratos Epimerases/genética , Reação em Cadeia da Polimerase/métodos , Transaminases/genética , Yersinia enterocolitica/classificação , Animais , Bovinos , DNA Bacteriano/análise , Humanos , Sorotipagem , Especificidade da Espécie , Yersinia enterocolitica/genéticaAssuntos
Infecções Estreptocócicas/tratamento farmacológico , Streptococcus pyogenes/isolamento & purificação , Tonsilite/tratamento farmacológico , Adulto , Criança , Diagnóstico Diferencial , Relação Dose-Resposta a Droga , Hemólise/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Recidiva , Infecções Estreptocócicas/diagnóstico , Tonsilite/diagnóstico , Tonsilite/microbiologiaRESUMO
A real-time, genus-specific 5' nuclease PCR assay for amplification of a 322-bp fragment of the per gene was developed for rapid (<2 h) identification of Brucella spp. from agar plates. The assay, including an internal amplification control (116 bp), identified Brucella strains (n = 23) and did not detect non-Brucella strains (n = 174), indicating its usefulness, particularly for laboratories with stringent quality assurance programs.