Bacteriophage-based latex agglutination test for rapid identification of Staphylococcus aureus (original) (raw)
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European Journal of Clinical Microbiology & Infectious Diseases, 2010
In this study, we evaluated a fourth-generation agglutination assay (Staph Plus; DiaMondiaL[DML]) for the rapid identification of Staphylococcus aureus. First, comparison with three third-generation assays (Slidex Staph Plus, bioMérieux; Staphaurex Plus, Murex Diagnostics; Pastorex Staph-Plus, Sanofi Diagnostics Pasteur) was performed on a predefined strain collection: 265 coagulase-negative staphylococci (CNS), 266 methicillinresistant S. aureus (MRSA) and 262 methicillin-susceptible S. aureus (MSSA) strains ("strain study"). Second, patient material-derived strains (883 CNS, 847 MSSA and 135 MRSA) were tested concurrently with both the DML and Slidex assays ("daily practice study"). In the strain study, the overall sensitivity and specificity of the DML, Slidex, Staphaurex and Pastorex assays were 99.2% and 100%, 98.1% and 100%, 95.2% and 100%, and 98.2% and 98.8%, respectively. Using the respective tests, the result was indeterminate in 0.0%, 0.6%, 0.4% and 1.5% of the strains. Overall, the sensitivity of the DML and Slidex assays were comparable in both sub-studies. However, in MRSA strains, the sensitivity of the DML assay was significantly lower than the Slidex assay. The specificity of the Slidex assay was significantly higher than the DML assay. However, the percentage of indeterminate results was much higher for the Slidex than the DML assay. In conclusion, the presumptive identification of S. aureus by the DML assay proved to be equal to third-generation latex agglutination assays. Recently, the Staph Plus Latex Kit (DiaMondiaL [DML], Sees, France), a new latex agglutination assay for the identification of S. aureus, has been marketed. In order to
Journal of Clinical Microbiology, 2001
A newly marketed rapid agglutination kit for the identification of Staphylococcus aureus , Slidex Staph Plus (bioMérieux), was compared to Staphaurex Plus (Murex Diagnostics) and Pastorex Staph-Plus (Sanofi Diagnostics Pasteur). The study took place in three clinical microbiology laboratories in three different European countries. A total of 892 staphylococcal isolates, including 278 methicillin-sensitive S. aureus (MSSA) isolates, 171 methicillin-resistant S. aureus (MRSA) isolates, and 443 coagulase-negative staphylococcal isolates, were analyzed. The sensitivities (MSSA/MRSA) and specificities, respectively, were 98.2% (98.9%/97.1%) and 98.9% for Slidex Staph Plus, 98.2% (98.2%/98.2%) and 96.2% for Staphaurex Plus, and 98.7% (98.6%/98.8%) and 95.7% for Pastorex Staph Plus. The specificity of the Slidex Staph Plus kit was statistically significantly higher than the specificities of Staphaurex Plus and Pastorex Staph-Plus. The Slidex Staph Plus is a very reliable test for the iden...
Comparison of five agglutination tests for identification of Staphylococcus aureus
Journal of clinical microbiology, 1997
Various commercially produced agglutination kits are widely used for the identification of Staphylococcus aureus. These kits detect the presence of protein A and/or clumping factor on S. aureus. The literature has shown that methicillin-resistant S. aureus (MRSA) isolates which are deficient in both clumping factor and protein A may be misidentified. Two products, Slidex and Staphaurex Plus, utilize specific anti-S. aureus antibodies, potentially giving them greater sensitivity compared to products without these antibodies. We report a prospective study designed to compare the performance characteristics of Fastaph, Slidex, Staphaurex, Staphaurex Plus, Staphyloslide, and the tube coagulase test for the identification of staphylococcal isolates. All discrepant isolates were tested with the Gen-Probe AccuProbe S. aureus test and were identified to the species level with conventional reference biochemicals. A total of 1,193 isolates were tested, including 33 MRSA and 423 methicillin-se...
Evaluation of Three Slide Agglutination Tests for Rapid Identification of Staphylococcus aureus
Acta Veterinaria Scandinavica, 1991
Three slide agglutination tests for identification of Staphylococcus aureus were compared. The agglutination tests used for evaluation were Staphaurex (Wellcome Diagnostics), Staphyslide-Test (BioMerieux), and ANI S. aureus TEST (Ani Biotech Oy). A total of 347 isolates were analyzed, including 288 strains of S. aureus, 49 of S. epidermis, 11 of S. intermedius, 12 strains of other staphylococci and 14 non-staphylococcal strains. One hundred of the S. aureus strains were isolates from cases of food poisoning, 129 from mastitis and 59 from other clinical cases. The sensitivities of the tests were also compared using diluted suspensions of S. aureus strains and with purified Protein A dilutions. The results showed that the sensitivities of the tests were 98.6 %, 97.9 % and 99.0 % for Staphaurex, Staphyslide-test and ANI S. aureus TEST, respectively. The specificities were 100 % for the Staphyslide test and 98.8 % for both the ANI S. aureus TEST and the Staphaurex test. The sensitivitie...
Assessment of the Agglutination Test for the Identification of Staphylococcus Aureus Isolates
Background: Staphylococcus aureus are among the most important and several pathogens in human infections. Objectives: The objectives of this study are to evaluate the efficacy of the agglutination test in the detection of Staphylococcus aureus in the laboratory and to identify the factors associated with staphylococcal infections. Methods: It is a prospective study of 100 isolates of staphylococci in a period of nine months from May 2021 to January 2022 in the University Hospital of Befelatanana. Results: Among of the 100 isolates of staphylococci, 49 (49%) were represented by Staphylococcus aureus. Concerning the prediction performance of the agglutination test, it has a sensitivity of 93.8%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value of 94.7%. Concerning the associated factors, the men (63%) (p=0.002), the patients aged 40 to 59 years (63%) (p=0.3; NS) and with suppuration (75%) (p=0.004) were the most affected by Staphylococcus aureus. Moreover, Staphylococcus aureus was often identified in pus samples (72.4%) (p=0.0009). Conclusion: In brief, agglutination test is a good test and can replace the standard gold test for the detection of Staphylococcus aureus.
Journal of Clinical Microbiology, 2004
We compared the performance of Staphychrom II (International Microbio, Signes, France), a rapid (2-h) chromogenic staphylocoagulase test that uses human prothrombin and protease inhibitors, with those of the reference tube coagulase test (TCT) and the latex agglutination test (LAT) Slidex Staph Plus for the rapid identification of S. aureus. Prospective evaluation with 293 fresh clinical isolates yielded sensitivities, specificities, and predictive and negative predictive values of .1%, respectively, for the Staphychrom II test; 98.6, 98.7, 99.6, and 96.3%, respectively, for LAT; and 97.6, 98.7, 99.5, and 93.9%, respectively, for TCT. The perfect specificity of the Staphychrom II test was confirmed by testing 193 collection strains selected because of their potential testing pitfalls. The Staphychrom II test was positive for 90% of the 215 S. aureus strains tested after only 1 h of incubation. The Staphychrom II test was as sensitive as the reference TCT and was 100% specific.
Analytical Letters, 2005
Different ELISA tests to detect and quantify levels of S. aureus in broth cultures were developed and compared. In all cases the assays were a modification of a "sandwich" format based on the use of common IgG as well as specific antibodies to bind protein A, an antigen localized in the cellular wall of S. aureus and partially extracted by boiling. Initially, human IgG was immobilized on the surface of microtitre plate wells in order to bind, by means of the Fc region, protein A that was present either in standard solutions or broth cultures of S. aureus treated by a boiling step.
Journal of clinical microbiology, 1993
A new immunoenzymatic assay (IEA) for the identification of Staphylococcus aureus strains of both human and animal origin was compared with rapid commercial kits. The sensitivities and specificities of the commercial kits varied from 90.2 to 96% and 90.8 to 93.7%, respectively. The IEA did not give any false-negative or false-positive results, while commercial kits gave high percentages of false-positive results among clumping factor-positive non-S. aureus strains. The IEA is particularly useful for isolates for which identification is doubtful, for large-scale epidemiological studies, and for identifying isolates from animals as S. aureus.
Organic & Biomolecular Chemistry, 2013
infection, and were part of a cohort of bacteria taken from UK hospitals. E.coli samples were a combination of clinical isolates and wild type strains (E.coli 1-10), and coagulase negative Staphylococci include strains of S.epidermidis, S. warneri, S.hominus and M. luteus, and were obtained from clinical isolates from Sutton hospital. All bacteria were cultured initially on Brain Heart infusion agar, after which they were subcultured twice onto nutrient agar overnight at 37 °C, under aerobic conditions. Each bacterial isolate possesses individual characteristics, and thus displays a variance in the amount of coagulase produced, and therefore there is a degree of variance in results, lending to a greater amount of error in the results depicted. Preparation of the LGX solution A 100 μM and 50 μM solution of compound 3 was prepared by dissolving it in 2.5 % methanol followed by dilution in 1 x PBS. Solutions of Tris Base (0.05 M) and NaCl (0.1 M) in deionised H 2 O were added to the solution until an optimum pH of 8.5 was achieved. The appropriate amount of human prothrombin in 1 x PBS was then added to produce final prothrombin concentrations of 83.6 nM and 41.8 nM, respectively. The resulting solution was termed "LGX". The concentrations of LGX, subsequently discussed, refer to the concentration of the active constituent compound 3. Testing procedure the efficacy of LGX as a selective and sensitive means of detecting S. aureus In order to detect the presence of staphylocoagulase and thus the efficacy of LGX, varying cell concentrations (10 6 , 10 5 , 10 3 , 10 2 CFU/mL (50 μM LGX) and 10 4 , 10 3 , 10 2 , 10 0 CFU/mL (100 μM LGX) were added to a microtitre plate (Nunclon 96 well plates) in a 1:1 ratio with either 50 μM or 100 μM of prepared LGX solution. This provided a final LGX concentration of 25 μM or 50 μM, respectively. The relative fluorescence was then recorded every fifteen minutes over a six hour time period (λ ex. = 488 nm and λ em. = 525 nm). Positive controls used in each experiment were a control strain of MRSA (NCTC 12493), and the negative control was a clinical isolate of E. coli. A 1:1 ratio of both the 100 μM and 50 μΜ of LGX solution with 1 x PBS was used, and termed "LGX alone". Fluorescence intensity was determined at 15 minute intervals over a 6 hour time period and n=3 samples were assayed in each case. We assayed 15 Strains of MRSA at varying cell concentration (10 6 , 10 5 , 10 3 , 10 2 CFU/mL (50 μM LGX) and 10 4 , 10 3 , 10 2 , 10 0 CFU/mL (100 μM) LGX)) with equal volume of both 50 μM and 100 μM LGX, respectively, to give a final LGX concentration of 25 μM or 50 μM, respectively, in addition to a strain of E-coli, which served as a negative control as described above.
Journal of Medical Microbiology, 2006
Most routine laboratory detection of Staphylococcus aureus isolates is based on rapid agglutination test systems. Failure of agglutination assays to identify meticillin-resistant S. aureus strains (MRSA) has been demonstrated. The aim of this study was to evaluate six commercially available agglutination tests for the detection of meticillin-sensitive S. aureus (MSSA) and mecA-positive MRSA strains. The Dry Spot Staphytect Plus H test (Oxoid), the Pastorex Staph Plus H test (Bio-Rad), the Slidex Staph-Kit H and Slidex Staph Plus H test (bioMé rieux), the Staphaurex Plus H test (Remel) and the Staphylase Test H (Oxoid) were used. As determined by pulsed field gel electrophoresis, 52 distinct MRSA strains from five countries, 83 MSSA strains and 150 coagulase-negative staphylococci were included. Species identification and determination of susceptibility patterns were performed using colony morphology, Gram stain, catalase testing, tube coagulase testing, DNase testing, mannitol fermentation, susceptibility testing towards oxacillin by Etest H , coagulase gene PCR, fibrinogen receptor gene PCR and PCR of the mecA gene. Sensitivity of the agglutination tests ranged from 82?7 to 100?0 % for MRSA strains and 92?8 to 100?0 % for MSSA strains, respectively. Specificity of the test systems ranged from 91?3 to 99?1 %. None of the six agglutination assays produced correct reactions for all staphylococci tested. Only the Dry Spot Staphytect Plus H test correctly identified all 52 MRSA strains. For the other tests kits, sensitivity of MRSA detection was lower than for MSSA isolates. Depending upon the local MRSA prevalence and the parameter of interest (sensitivity or specificity), these test systems may be useful for routine diagnostic purposes.