Accuracy of a routine real-time PCR assay for the diagnosis of Pneumocystis jirovecii pneumonia.
J Microbiol Methods
; 75(2): 258-61, 2008 Oct.
Article
em En
| MEDLINE
| ID: mdl-18606198
ABSTRACT
Pneumocystis jirovecii is a common cause of life-threatening pneumonia among immunocompromised patients. Using 400 fresh bronchoalveolar lavage samples, we compared prospectively routine direct immunofluorescence assay (DFA) and a real-time PCR assay, performed on a LightCycler system, for the detection of P. jirovecii. Among the 66 PCR positive samples, 31 were positive by DFA. No patient was found as having the pattern "PCR--ve/DFA+ve". The semi-quantification of the P. jirovecii DNA was represented by the cycle threshold (Ct). Using DFA as the gold standard, the sensitivity of the PCR was 100% for Ct > or = 28 and the specificity was 100% for Ct < 22. Between these two points, the results could be discrepant. The patients of the "22 < or = Ct < 28" group presented more frequently with a radiological interstitial syndrome than the "Ct > or = 28" group, and presented less frequently with HIV-infection and elevated lactate dehydrogenase (LDH) assay than in the "Ct < 22" group. A negative PCR allowed us to exclude the P. jirovecii pneumonia. The real-time PCR assay seems to be an accurate diagnosis method and could replace the DFA. The semi-quantitative results should be helpful to distinguish colonized, subclinically infected and P. jirovecii pneumonia patients.
Texto completo:
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Bases de dados:
MEDLINE
Assunto principal:
Pneumonia por Pneumocystis
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Reação em Cadeia da Polimerase
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Pneumocystis carinii
Tipo de estudo:
Diagnostic_studies
/
Evaluation_studies
Limite:
Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
J Microbiol Methods
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
França