Quantitative Pneumocystis jirovecii real-time PCR to differentiate disease from colonisation.
Pathology
; 53(7): 896-901, 2021 Dec.
Article
in En
| MEDLINE
| ID: mdl-34217515
ABSTRACT
We studied a Pneumocystis jirovecii quantitative polymerase chain reaction (qPCR) for distinguishing P. jirovecii disease from colonisation. Eighty-two respiratory samples from 65 patients with qPCR results were analysed against a gold standard clinical diagnosis of Pneumocystis pneumonia. High inter-assay reproducibility using recombinant and clinical material was observed. Contemporaneous samples from the same patient displayed high variability (median difference 2.6 log10 copies/mL, IQR 2.1-3.1 log10 copies/mL). Despite this, area under the receiver operator characteristic curve was 0.8. An optimum cut-off of 2.8 log10 copies/mL (equivalent to CT of 34.0 cycles) had 59% sensitivity and 92% specificity. The median P. jirovecii load was 7.3 log10 copies/mL in HIV patients compared to 2.6 log10 copies/mL in non-HIV patients. Specificity was 100% in non-HIV patients with qPCR of >3.8 log10 copies/mL. qPCR was useful for distinguishing P. jirovecii disease from colonisation. A quantitative standard, standardisation of definitions and methods are required to improve the generalisability of results.
Key words
Full text:
1
Database:
MEDLINE
Main subject:
Pneumonia, Pneumocystis
/
HIV Infections
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Pneumocystis Infections
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Pneumocystis carinii
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Real-Time Polymerase Chain Reaction
Type of study:
Diagnostic_studies
Limits:
Aged
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Female
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Humans
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Male
/
Middle aged
Language:
En
Year:
2021
Type:
Article