Comparision Of Tube Coagulase Test With Mannitol Fermentation Test For Diagnosis Of Staphylococcus Aureus
Comparision Of Tube Coagulase Test With Mannitol Fermentation Test
Keywords:
Staphylococcus aureus, Mannitol fermentation, Coagulase test, Human plasmaAbstract
Introduction: Staphylococcus is one of the most common bacteria routinely isolated in microbiological laboratories. Identification of staphylococcus at species level requires battery of tests. In developing countries identification at species level is usually done by coagulase test (slide & Tube). Coagulase test requires human or sheep plasma. Human & sheep plasma has the disadvantage of having low sensitivity & low specificity and risk of biohazard. Mannitol fermentation is an important tool for diagnosis of staphylococcus at species level and it also overcomes the disadvantage of coagulase test. The objective of this study was to compare sensitivity of mannitol fermentation test with coagulase test for identification of S aureus. Material & Methods: Among all clinical samples received, 100 isolates of Staphylococcus were compared for coagulase test (slide &tube) & mannitol fermentation. Results: In our study, among 100 staphylococcal isolates, positive mannitol fermentation test reaction was seen in all 100 isolates while positive tube coagulase test was seen among 94 isolates. Conclusion: Sensitivity of Mannitol fermentation test is more as compared to coagulase test. Mannitol fermentation test can be used for diagnosis of S. aureus along with coagulase test to improve the sensitivity of coagulase test or it can also be used as single gold standard method for diagnosis of S. aureus.
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