RESUMEN
OBJECTIVES: This study examined Klebsiella pneumoniae clinical isolates and their bla(KPC) plasmids to determine potential relatedness of the isolates and their plasmids harbouring carbapenem resistance mechanisms. METHODS: K. pneumoniae carbapenemase (KPC)-producing K. pneumoniae from New York City (NYC) (nâ=â19) and Toronto (nâ=â2) were typed by PFGE and multilocus sequence typing (MLST). bla(KPC)-harbouring plasmids were transformed into Escherichia coli DH10B(TM), restricted using EcoRI and analysed for bla content and replicon (rep) type. Susceptibility profiles for clinical and transformed strains were determined by automated microbroth dilution using CLSI breakpoints. Outer membrane protein (OMP) genes were analysed by sequencing of ompk35 and ompk36. RESULTS: PFGE analysis identified 17 related strains (≥ 80% similarity; 11 KPC-2, 6 KPC-3) where ST258 was the dominant clonal type. All clinical isolates contained both bla(SHV) and bla(TEM-1) and, with the exception of one isolate, were multidrug resistant (MDR). Transformed KPC plasmids (nâ=â21) carried TEM-1 (nâ=â18) and were MDR (nâ=â5). Three plasmid clusters, repFIIA (nâ=â10), repR (nâ=â3) and an unknown type (nâ=â3), were observed. repFllA plasmids were observed from both NYC and Toronto strains. OMP gene analysis revealed premature stop codons in ompk35 and numerous deletions and insertions in ompk36. CONCLUSIONS: The dissemination of bla(KPC) is due both to carriage of similar KPC-harbouring plasmids within genetically distinct K. pneumoniae and to clonal spread of K. pneumoniae with unrelated KPC plasmids.
Asunto(s)
Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/enzimología , Klebsiella pneumoniae/genética , Plásmidos , Resistencia betalactámica , beta-Lactamasas/genética , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Proteínas de la Membrana Bacteriana Externa/genética , Técnicas de Tipificación Bacteriana , Canadá , Carbapenémicos/farmacología , Electroforesis en Gel de Campo Pulsado , Femenino , Transferencia de Gen Horizontal , Humanos , Klebsiella pneumoniae/clasificación , Klebsiella pneumoniae/aislamiento & purificación , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Epidemiología Molecular , Tipificación Molecular , Tipificación de Secuencias Multilocus , Ciudad de Nueva York , Transformación BacterianaRESUMEN
BACKGROUND: Angiotensin converting enzyme 2 (ACE2), a monocarboxylase that degrades angiotensin II to angiotensin 1-7, is also the functional receptor for severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) and is highly expressed in the lungs and heart. Patients with SARS also suffered from cardiac disease including arrhythmias, sudden cardiac death, and systolic and diastolic dysfunction. MATERIALS AND METHODS: We studied mice infected with the human strain of the SARS-CoV and encephalomyocarditis virus and examined ACE2 mRNA and protein expression. Autopsy heart samples from patients who succumbed to the SARS crisis in Toronto (Canada) were used to investigate the impact of SARS on myocardial structure, inflammation and ACE2 protein expression. RESULTS: Pulmonary infection with the human SARS-CoV in mice led to an ACE2-dependent myocardial infection with a marked decrease in ACE2 expression confirming a critical role of ACE2 in mediating SARS-CoV infection in the heart. The SARS-CoV viral RNA was detected in 35% (7/20) of autopsied human heart samples obtained from patients who succumbed to the SARS crisis during the Toronto SARS outbreak. Macrophage-specific staining showed a marked increase in macrophage infiltration with evidence of myocardial damage in patients who had SARS-CoV in their hearts. The presence of SARS-CoV in the heart was also associated with marked reductions in ACE2 protein expression. CONCLUSIONS: Our data show that SARS-CoV can mediate myocardial inflammation and damage associated with down-regulation of myocardial ACE2 system, which may be responsible for the myocardial dysfunction and adverse cardiac outcomes in patients with SARS.
Asunto(s)
Enfermedades Cardiovasculares/virología , Miocardio/patología , Peptidil-Dipeptidasa A/metabolismo , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/metabolismo , Enzima Convertidora de Angiotensina 2 , Animales , Autopsia , Enfermedades Cardiovasculares/prevención & control , Regulación hacia Abajo , Humanos , Inmunohistoquímica , Masculino , Ratones , Peptidil-Dipeptidasa A/genética , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética , Activación ViralRESUMEN
Recent studies show that multidrug-resistant Streptococcus pneumoniae serotype 19A continues to emerge as a cause of invasive pneumococcal disease after the introduction of Prevnar. We report a case of multidrug-resistant S. pneumoniae serotype 19A meningitis successfully treated with vancomycin and levofloxacin. This case reinforces the need for the empiric use of vancomycin in meningitis and the need for alternative treatments.
Asunto(s)
Meningitis Neumocócica/tratamiento farmacológico , Antibacterianos/uso terapéutico , Cefuroxima/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Quimioterapia Combinada , Humanos , Lactante , Levofloxacino , Meningitis Neumocócica/diagnóstico , Pruebas de Sensibilidad Microbiana , Ofloxacino/uso terapéutico , Streptococcus pneumoniae , Vancomicina/uso terapéuticoRESUMEN
Three commercially available real-time reverse transcriptase PCR assays (the Artus RealArt HPA coronavirus LightCycler, the Artus RealArt HPA coronavirus Rotor-Gene, and the EraGen severe acute respiratory syndrome coronavirus POL assay) and three RNA extraction methodologies were evaluated for the detection of severe acute respiratory syndrome coronavirus RNA from 91 stool specimens. The assays' sensitivities were highest (58% to 75%) for specimens obtained 8 to 21 days after symptom onset. The assays were less sensitive when specimens were obtained less than 8 days or more than 21 days after the onset of symptoms. All assays were 100% specific.
Asunto(s)
Heces/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/aislamiento & purificación , Humanos , ARN Viral/aislamiento & purificación , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética , Sensibilidad y EspecificidadRESUMEN
Ciprofloxacin resistance was identified in 18% and 6% of consecutively collected, clinically significant urinary tract isolates of Escherichia coli from inpatients and outpatients, respectively. In comparison to ciprofloxacin-susceptible isolates, there were fewer resistant isolates that expressed beta-hemolysis (outpatient, 9% versus 87%, P < 0.0001; inpatient, 4% versus 76%, P < 0.0001) and that had a papEF genotype, genes encoding P fimbriae (outpatient, 30% versus 70%, P = 0.0004; inpatient, 26% versus 70%, P < 0.0001).
Asunto(s)
Bacteriuria/microbiología , Ciprofloxacina/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/patogenicidad , Factores de Virulencia/análisis , Farmacorresistencia Bacteriana , Hemólisis , Humanos , Ácido Nalidíxico/farmacologíaRESUMEN
The medical records of 39 patients with Acinetobacter bacteremia identified in the period between 1985 and 1995 were reviewed. In 24 cases (62%) the bacteremia was considered to have been clinically significant. Most of the infections (79%) were nosocomial, and the majority of these were acquired in an intensive care unit. Ten (42%) patients developed septic shock complicating the bacteremia and 13 (54%) died. In most of these cases (85%), Acinetobacter bacteremia was thought to have caused or contributed to death. The following variables were associated with a greater risk of mortality: age > 65 years (OR = 16; p = 0.01); development of septic shock (OR = 22; p = 0.004); and the presence of coagulopathy (OR = 20; p = 0.03).
Asunto(s)
Infecciones por Acinetobacter/epidemiología , Bacteriemia/epidemiología , Acinetobacter/efectos de los fármacos , Infecciones por Acinetobacter/diagnóstico , Infecciones por Acinetobacter/mortalidad , Adulto , Factores de Edad , Anciano , Antibacterianos/farmacología , Bacteriemia/complicaciones , Bacteriemia/diagnóstico , Trastornos de la Coagulación Sanguínea/complicaciones , Infección Hospitalaria/microbiología , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Choque Séptico/diagnóstico , Choque Séptico/epidemiología , Choque Séptico/mortalidadRESUMEN
Antimicrobial resistance was characterized for 14 strains of Streptococcus mitis. HinfI restriction fragment length mapping of gyrA PCR amplicons from three ciprofloxacin-resistant isolates correlated with mutations associated with such resistance in other organisms. By using PCR, seven erythromycin-resistant strains were found to possess either the mef or ermB gene. Hybridization revealed tet(M) in seven tetracycline-resistant isolates.