Biomaterial Database

Comparison of commercial slide agglutination kits with a tube coagulase test for the rapid identification of Staphylococcus aureus from blood culture. 1997

R P Cooke, and C T Jenkins

Department of Medical Microbiology, District General Hospital, East Sussex.

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.

UI	MeSH Term	Description	Entries
D011237	Predictive Value of Tests	In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.	Negative Predictive Value,Positive Predictive Value,Predictive Value Of Test,Predictive Values Of Tests,Negative Predictive Values,Positive Predictive Values,Predictive Value, Negative,Predictive Value, Positive
D011933	Reagent Kits, Diagnostic	Commercially prepared reagent sets, with accessory devices, containing all of the major components and literature necessary to perform one or more designated diagnostic tests or procedures. They may be for laboratory or personal use.	Diagnostic Reagent Kits,Diagnostic Reagents and Test Kits,Diagnostic Test Kits,In Vitro Diagnostic Device,In Vitro Diagnostic Devices,In Vitro Diagnostic Medical Device,In Vitro Diagnostic Medical Devices,Kits, Diagnostic Reagent,Diagnostic Reagent Kit,Diagnostic Test Kit,Kit, Diagnostic Reagent,Kit, Diagnostic Test,Kits, Diagnostic Test,Reagent Kit, Diagnostic,Test Kit, Diagnostic,Test Kits, Diagnostic
D000372	Agglutination Tests	Tests that are dependent on the clumping of cells, microorganisms, or particles when mixed with specific antiserum. (From Stedman, 26th ed)	Agglutination Test,Test, Agglutination,Tests, Agglutination
D001431	Bacteriological Techniques	Techniques used in studying bacteria.	Bacteriologic Technic,Bacteriologic Technics,Bacteriologic Techniques,Bacteriological Technique,Technic, Bacteriological,Technics, Bacteriological,Technique, Bacteriological,Techniques, Bacteriological,Bacteriologic Technique,Bacteriological Technic,Bacteriological Technics,Technic, Bacteriologic,Technics, Bacteriologic,Technique, Bacteriologic,Techniques, Bacteriologic
D012189	Retrospective Studies	Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.	Retrospective Study,Studies, Retrospective,Study, Retrospective
D012680	Sensitivity and Specificity	Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)	Specificity,Sensitivity,Specificity and Sensitivity
D013203	Staphylococcal Infections	Infections with bacteria of the genus STAPHYLOCOCCUS.	Infections, Staphylococcal,Staphylococcus aureus Infection,Staphylococcal Infection,Staphylococcus aureus Infections
D013211	Staphylococcus aureus	Potentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.