RESUMO
We report an outbreak of linezolid-resistant Staphylococcus haemolyticus strains (MIC 32 mg/L) in patients admitted to the Verona University Hospital Intensive Care Unit. The strains proved to be clonally related at pulsed field gel electrophoresis. All the strains showed the G2576T mutation responsible for linezolid-resistance and retained their resistance even after several passages on antibiotic-free medium. After a decade of linezolid use, multifocal emergence of linezolid resistance in coagulase-negative staphylococci has become an important matter of concern and mandates stricter control over the use of this antibiotic in order to preserve its clinical utility.
Assuntos
Acetamidas/farmacologia , Antibacterianos/farmacologia , Surtos de Doenças , Farmacorresistência Bacteriana , Oxazolidinonas/farmacologia , Infecções Estafilocócicas/epidemiologia , Staphylococcus haemolyticus/isolamento & purificação , Idoso , Eletroforese em Gel de Campo Pulsado , Genótipo , Humanos , Unidades de Terapia Intensiva , Itália/epidemiologia , Linezolida , Masculino , Testes de Sensibilidade Microbiana , Tipagem Molecular , Mutação Puntual , Infecções Estafilocócicas/microbiologia , Staphylococcus haemolyticus/efeitos dos fármacosRESUMO
We describe a case of fungal keratitis due to Beauveria bassiana in a farmer with Fuchs' dystrophy, treated with amphotericin B. Surgery with penetrating keratoplasty was necessary to resolve the lesions. Susceptibility testing and molecular sequencing permitted the identification and treatment of this rare aetiological agent of invasive fungal disease.
RESUMO
The aim of this study was to determine the accuracy of commercial systems (VITEK® 2, Etest and Sensititre®) in determining the minimum inhibitory concentrations of vancomycin, teicoplanin and linezolid of Staphylococcus aureus strains and to evaluate the reproducibility of each system in a clinical microbiology laboratory. In total, 115 strains of S. aureus isolated from blood cultures were tested with all three commercial methods as well as the broth microdilution method, which is designated as the standard for glycopeptides and linezolid. Fourteen different S. aureus strains were included in a reproducibility test for all methods and antibiotics. For these strains, antimicrobial susceptibility testing was repeated 10 times on different days with all four methods, each time using the same inoculum. All three commercial methods exhibited similar performance in categorisation of nearly all of the meticillin-susceptible S. aureus (MSSA) isolates. Discrepancies were registered for meticillin-resistant S. aureus (MRSA); 2.5% of the strains in the intermediate or resistant category with the VITEK 2 system were not recognised as resistant by Etest and Sensititre. Moreover, none of the three commercial methods provided accurate results compared with homemade broth microdilution. Reproducibility of vancomycin and teicoplanin was 100% with VITEK 2 and Sensititre and 98.75% with Etest. Microdilution showed a reproducibility of 95.6% with vancomycin and 83.1% with teicoplanin. In contrast to previous reports, the best agreement with microdilution was exhibited by VITEK 2 both for MSSA and MRSA. For the antibiotics tested, the best reproducibility was obtained with the VITEK 2 and Sensititre systems.
RESUMO
We report a case of fungemia caused by Candida magnoliae, a yeast never associated with human disease. The infection occurred in a 42-year-old Chinese patient with gastric cancer complicated by peritoneal carcinosis. Multiple blood cultures were positive for yeast; the species was well identified with biochemical and molecular methods. The phylogenetic analysis showed a close relationship of C. magnoliae to Candida krusei.
Assuntos
Candida/isolamento & purificação , Fungemia/microbiologia , Neoplasias Gástricas/complicações , Adulto , Sequência de Bases , Candida/classificação , Candida/efeitos dos fármacos , Humanos , Masculino , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , FilogeniaRESUMO
We report on a case of cutaneous infection caused by Alternaria infectoria in a cardiac transplant recipient. A rapid molecular diagnosis was obtained by sequence analysis of the internal transcribed spacer domain of the 5.8S ribosomal DNA region amplified from colonies developed on Sabouraud medium. Treatment consisted of a combination of systemic antifungal therapy, first with amphotericin B and then with itraconazole.
Assuntos
Alternaria/classificação , Alternaria/genética , Dermatomicoses/microbiologia , Transplante de Coração/efeitos adversos , Infecções Oportunistas/microbiologia , Alternaria/isolamento & purificação , Meios de Cultura , DNA Fúngico/análise , DNA Espaçador Ribossômico/análise , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Tipagem Micológica , Reação em Cadeia da Polimerase , RNA Ribossômico 5,8S/genéticaRESUMO
A nosocomial cluster of Candida guillermondii fungemia ( n=5 episodes) occurred in a surgical unit over a 2-week period. The five infected patients had received parenteral nutrition through central lines and three of them had catheter-related candidemia. All of the isolates were resistant to 5-flucytosine (MIC >32 microg/ml) and they had strictly related fingerprints, as generated by randomly amplified polymorphic DNA analysis. Although no isolate of Candida guillermondii was recovered from other clinical, surveillance or environmental samples, nosocomial spread of this yeast stopped following the reinforcement of infection control measures. Candida guillermondii may require an intravascular foreign body to cause fungemia, but the outbreak reported here shows that it can be transmitted nosocomially and cause epidemics.