Quantitative PCR for Etiologic Diagnosis of Methicillin-Resistant Staphylococcus aureus Pneumonia in Intensive Care Unit / 결핵및호흡기질환
Tuberculosis and Respiratory Diseases
;
: 293-301, 2012.
Artigo
em Inglês
| WPRIM
| ID: wpr-114985
ABSTRACT
BACKGROUND:
Ventilator-associated pneumonia (VAP) requires prompt and appropriate treatment. Since methicillin-resistant Staphylococcus aureus (MRSA) is a frequent pathogen in VAP, rapid identification of it, is pivotal. Our aim was to evaluate the utility of quantitative polymerase chain reaction (qPCR) as a useful method for etiologic diagnoses of MRSA pneumonia.METHODS:
We performed qPCR for mecA, S. aureus-specific femA-SA, and S. epidermidis-specific femA-SE genes from bronchoalveolar lavage or bronchial washing samples obtained from clinically-suspected VAP. Molecular identification of MRSA was based on the presence of the mecA and femA-SA gene, with the absence of the femA-SE gene. To compensate for the experimental and clinical conditions, we spiked an internal control in the course of DNA extraction. We estimated number of colony-forming units per mL (CFU/mL) of MRSA samples through a standard curve of a serially-diluted reference MRSA strain. We compared the threshold cycle (Ct) value with the microbiologic results of MRSA.RESULTS:
We obtained the mecA gene standard curve, which showed the detection limit of the mecA gene to be 100 fg, which corresponds to a copy number of 30. We chose cut-off Ct values of 27.94 (equivalent to 1x10(4) CFU/mL) and 21.78 (equivalent to 1x10(5) CFU/mL). The sensitivity and specificity of our assay were 88.9% and 88.9% respectively, when compared with quantitative cultures.CONCLUSION:
Our results were valuable for diagnosing and identifying pathogens involved in VAP. We believe our modified qPCR is an appropriate tool for the rapid diagnosis of clinical pathogens regarding patients in the intensive care unit.
Texto completo:
DisponíveL
Índice:
WPRIM (Pacífico Ocidental)
Assunto principal:
Pneumonia
/
Entorses e Distensões
/
Células-Tronco
/
DNA
/
Adenosina
/
Reação em Cadeia da Polimerase
/
Resistência a Meticilina
/
Lavagem Broncoalveolar
/
Cuidados Críticos
/
Complexo I de Proteína do Envoltório
Tipo de estudo:
Estudo diagnóstico
/
Estudo de etiologia
Limite:
Humanos
Idioma:
Inglês
Revista:
Tuberculosis and Respiratory Diseases
Ano de publicação:
2012
Tipo de documento:
Artigo
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