Oxacillin Susceptibility Testing of Staphylococci Directly from Bactec Plus Blood Cultures by the BBL Crystal MRSA ID System

Abstract

The BBL Crystal MRSA ID test (Becton Dickinson) was applied directly to blood culture vials containing clusters of gram-positive cocci. The sensitivity and specificity of the test were 84 and 100% and 54 and 100% for vials containing Staphylococcus aureusand coagulase-negative staphylococci, respectively. This test is a reliable method for direct detection of methicillin resistance in positive blood culture vials when S. aureus is identified in parallel by rapid identification procedures.

Molecular Diagnostics and Comparative Genomics in Clinical Microbiology

“…The BBl crystal mrsa Id test assesses viability by means of biochemical detection of oxygen consumption through a fluorescent compound Fluorescence, commercially available multi-well system for assessing growth in the presence of various antibiotics Qadri et al (1994); Zambardi et al (1996); Kubina et al (1999) The soft salt mannitol agar cloxacillin test consists of tubes containing this medium; can be used at bedside for direct swab inoculation An indicator substance induces a color change upon the presence of MRSA Mir et al (1998) chromagar staph aureus and oxa resistance screen agar are chromogenic plate media; addition of 4 g/ml renders the media suitable for MRSA identification S. aureus colonies on the agar show a distinct purple color on Chromagar; some problems have been noted with test sensitivity Merlino et al (2000); Apfalter et al (2002) lipovitellin salt mannitol agar is a selective medium; lipovitellin is a glycosylated, lipid binding protein present in the yolk of egg laying animals, showing homology to human apolipoprotein B Growth or not Verghese et al (1999) vitek technology is developed by bioMerieux and represents automated biochemical and antimicrobial screening of bacterial isolates…”