RT Journal Article
SR Electronic
T1 Comparison of commercial slide agglutination kits with a tube coagulase test for the rapid identification of Staphylococcus aureus from blood culture.
JF Journal of Clinical Pathology
JO J Clin Pathol
FD BMJ Publishing Group Ltd and Association of Clinical Pathologists
SP 164
OP 166
DO 10.1136/jcp.50.2.164
VO 50
IS 2
A1 R P Cooke
A1 C T Jenkins
YR 1997
UL http://jcp.bmj.com/content/50/2/164.abstract
AB Eighty clinical specimens of BACTEC 9240 blood culture vials, culture positive for staphylococci (38 Staphylococcus aureus and 42 coagulase negative staphylococci), were tested directly for the presence of clumping factor/protein A and free coagulase. Seven commercial slide agglutination kits were compared with a direct-tube coagulase (DTC) method. All tests were performed on blood culture pellets. Sensitivity, specificity, and negative and positive predictive values for the seven commercial kits were extremely variable, whereas a two-hour DTC test was highly predictive of S aureus. There was no significant difference between a two-, six- or 24-hour DTC test. Three (8%) S aureus isolates remained DTC negative even after 24 hours' incubation. Staphylococcal slide agglutination kits should not be used directly on blood culture broths. In contrast, a two-hour DTC test is a useful, rapid screening test for S aureus bacteraemia, provided isolates from DTC negative blood culture broths are re-tested using standard laboratory techniques.