Detection of methicillin resistance in Staphylococcus aureus isolated from pediatric patients: is the cefoxitin disk diffusion test accurate enough?
AUTOR(ES)
Mimica, M.J., Berezin, E.N., Carvalho, R.L.B., Mimica, I.M., Mimica, L.M.J., Sáfadi, M.A.P., Schneider, E., Caiaffa-Filho, H.H.
FONTE
Brazilian Journal of Infectious Diseases
DATA DE PUBLICAÇÃO
2007-08
RESUMO
We evaluated the performance of several methods for the detection of methicillin resistance in Staphylococcus aureus using 101 clinical S. aureus isolates from pediatric patients in a tertiary hospital in Brazil; 50 isolates were mecA-positive and 51 were mecA-negative. The Etest and oxacillin agar screening plates were 100% sensitive and specific for mecA presence. Oxacillin and cefoxitin disks gave sensitivities of 96 and 92%, respectively, and 98% specificity. Alterations of CLSI cefoxitin breakpoints increased sensitivity to 98%, without decreasing specificity. Our results highlight the importance of a continuing evaluation of the recommended microbiological methods by different laboratories and in different settings. If necessary, laboratories should use a second test before reporting a strain as susceptible, especially when testing strains isolated from invasive or serious infections. With the new (2007) CLSI breakpoints, the cefoxitin-disk test appears to be a good option for the detection of methicillin resistance in S. aureus.
Documentos Relacionados
- Comparison of cefoxitin disk diffusion test and mecA gene PCR results for methicillin resistance detection in Staphylococcus intermedius group isolates from canine origin in Brazil
- Reevaluation of the ability of the standardized disk diffusion test to detect methicillin-resistant strains of Staphylococcus aureus.
- Evaluation of Three Techniques for Detection of Low-Level Methicillin-Resistant Staphylococcus aureus (MRSA): a Disk Diffusion Method with Cefoxitin and Moxalactam, the Vitek 2 System, and the MRSA-Screen Latex Agglutination Test
- Rapid Slide Latex Agglutination Test for Detection of Methicillin Resistance in Staphylococcus aureus
- Rapid Detection of Methicillin Resistance in Staphylococcus aureus Isolates by the MRSA-Screen Latex Agglutination Test