Evaluation of Biofilm Formation and Presence of Ica Genes in Staphylococcus epidermidis Clinical Isolates
Osong Public Health and Research Perspectives
; (6): 160-166, 2018.
Article
Dans En
| WPRIM
| ID: wpr-716454
Responsable en Bibliothèque :
WPRO
ABSTRACT
OBJECTIVES:
Biofilm formation is one of the important features of Staphylococcus epidermidis, particularly in nosocomial infections. We aimed to investigate the biofilm production by phenotypic methods and the presence of ica genes in S epidermidis.METHODS:
A total of 41 S epidermidis isolates were recovered from different clinical specimens. Biofilm formation was evaluated by microtiter plate, tube method and Congo red agar method. The presence of icaA and icaD genes was investigated by PCR. Validity of methods (sensitivity and specificity), and metrics for test performance (positive/negative predictive value, and positive/negative likelihood ratio) were determined.RESULTS:
By both microtiter plate and tube method, 53.6% of S epidermidis isolates were able to produce biofilm, whilst only 24.4% of isolates provided a biofilm phenotype on Congo red agar plates. icaA and icaD genes were found in 100% and 95.1% of isolates, respectively. Biofilm phenotypes accounted for 4.8% by microtiter plate assay, despite the absence of the ica gene. Congo red agar and PCR exhibited a lower sensitivity (18% and 45.5%, respectively) for identifying the biofilm phenotype in comparison to microtiter plate.CONCLUSION:
The microtiter plate method remains generally a better tool to screen biofilm production in S epidermidis. In addition, the ability of S epidermidis to form biofilm is not always dependent on the presence of ica genes, highlighting the importance of ica-independent mechanisms of biofilm formation. The use of reliable methods to specifically detect biofilms can be helpful to treat the patients affected by such problematic bacteria.
Texte intégral:
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Indice:
WPRIM
Sujet Principal:
Opéron
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Phénotype
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Staphylococcus
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Staphylococcus epidermidis
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Bactéries
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Réaction de polymérisation en chaîne
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Infection croisée
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Biofilms
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Rouge Congo
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Agar-agar
Limites du sujet:
Humans
langue:
En
Texte intégral:
Osong Public Health and Research Perspectives
Année:
2018
Type:
Article