Detection of Pneumocystis jirovecii and Aspergillus spp. DNa in bronchoalveolar lavage fluids by commercial real-time PCr assays: comparison with conventional diagnostic tests.
The present study employed two commercial real-time PCR kits, MycAssay� Pneumocystis (PJ-PCR) and MycAssay� Aspergillus (ASP-PCR), for the search of fungal DNA on 44 bronchoalveolar lavage (BAL) fluids from patients at risk of invasive fungal disease. Operationally, on the basis of clinical diagnosis and according to the European Organization for Research and Treatment Cancer/Mycoses Study Group (EORTC/MSG) criteria, patients were clustered in 3 groups: a P. jirovecii pneumonia (PCP) group, an invasive aspergillosis (IA) group and a control (CTRL) group, consisting of 8, 10 and 24 patients, respectively. The results were compared to those obtained with conventional diagnostic assays, including BAL culture, galactomannan-ELISA (GM) and immunofluorescence (IF). The PJ-PCR assay returned a sensitivity and specificity of 100% and 94.4%, respectively. The ASP-PCR assay showed a sensitivity and specificity of 80% and 97.1%. When compared to the culture assay, the ASP-PCR showed enhanced sensitivity, and a good level of agreement (kappa = 0.63) was observed between ASP-PCR and GM assays. Overall, our data emphasize the diagnostic usefulness of the two commercial real-time PCR assays, especially in high-risk patients where timing is critical and a low fungal burden may hamper correct and prompt diagnosis by conventional tests.
Dipartimento di Scienze della Salute, Università degli Studi di Milano, Polo Universitario San Paolo, Milano, Italy.
Carlotta Francesca
CF
Orsi
Clotilde
C
Bettua
Pietro
P
Pini
Claudia
C
Venturelli
Annunziata
A
La Regina
Giulia
G
Morace
Mario
M
Luppi
Fabio
F
Forghieri
Sara
S
Bigliardi
Fabrizio
F
Luppi
Mauro
M
Codeluppi
Massimo
M
Girardis
Elisabetta
E
Blasi
D000328:Adult; D000368:Aged; D001228:Aspergillosis / Q000175:diagnosis* / Q000382:microbiology; D001230:Aspergillus / Q000235:genetics / Q000302:isolation & purification*; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology*; D004269:DNA, Bacterial / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005455:Fluorescent Antibody Technique / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D045363:Pneumocystis carinii / Q000235:genetics / Q000302:isolation & purification*; D011020:Pneumonia, Pneumocystis / Q000175:diagnosis* / Q000382:microbiology; D060888:Real-Time Polymerase Chain Reaction / Q000191:economics / Q000379:methods*
D004269:DNA, Bacterial