Evaluation of a novel medium for screening specimens from hospitalized patients to detect methicillin-resistant Staphylococcus aureus

Détails

ID Serval
serval:BIB_51C2B4FBD215
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Evaluation of a novel medium for screening specimens from hospitalized patients to detect methicillin-resistant Staphylococcus aureus
Périodique
Journal of Clinical Microbiology
Auteur(s)
Blanc  D. S., Wenger  A., Bille  J.
ISSN
0095-1137
Statut éditorial
Publié
Date de publication
08/2003
Peer-reviewed
Oui
Volume
41
Numéro
8
Pages
3499-502
Notes
Journal Article --- Old month value: Aug
Résumé
A novel medium, Oxacillin Resistant Screening Agar (ORSA) medium, was evaluated for the screening of specimens for methicillin-resistant Staphylococcus aureus (MRSA) in the hospital setting. Screening swabs (swabs of the nose, throat, perineum, and infected sites) were inoculated onto the new ORSA medium and into an enrichment broth (Muller-Hinton broth supplemented with NaCl and oxacillin). After 24 h of incubation, the enrichment broth was subcultured onto one ORSA plate and one lipovitellin Chapman salt agar plate. The sensitivities for the detection of MRSA were calculated for each medium alone and for the media in combination. A low sensitivity (74%) was obtained when ORSA medium was used alone as a primary culture, whereas the sensitivity was 88% when a single selective enrichment broth was used. Among the 414 blue colonies observed on ORSA plates, only 47% were found to be MRSA, 40% were coagulase-negative staphylococci, 7% were Enterococcus species, and 2% were methicillin-sensitive S. aureus. The optimal incubation time for the ORSA plates was evaluated. On primary culture, 38% of the blue MRSA colonies were visible only after 48 h of incubation (no blue colonies were not seen after 24 h of incubation), whereas 94% of the colonies were already visible at 24 h when ORSA plates were used for subcultures. In conclusion, the advantage of the novel ORSA medium is the ease of recognition of mannitol-fermenting bacteria, but further identification tests are needed to confirm the identification of S. aureus. An enrichment broth is still needed to ensure a good sensitivity for the recovery of MRSA, and an incubation time of 48 h is required for primary culture on ORSA medium.
Mots-clé
Cross Infection/diagnosis/microbiology *Culture Media Humans Laboratory Techniques and Procedures *Methicillin Resistance Staphylococcal Infections/*diagnosis Staphylococcus aureus/classification/*growth & development/*isolation & purification
Pubmed
Web of science
Création de la notice
29/01/2008 16:20
Dernière modification de la notice
03/03/2018 17:11
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