AUTHOR=Zhao Yanan , Garnaud Cécile , Brenier-Pinchart Marie-Pierre , Thiébaut-Bertrand Anne , Saint-Raymond Christel , Camara Boubou , Hamidfar Rebecca , Cognet Odile , Maubon Danièle , Cornet Muriel , Perlin David S. 

TITLE=Direct Molecular Diagnosis of Aspergillosis and CYP51A Profiling from Respiratory Samples of French Patients

JOURNAL=Frontiers in Microbiology

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2016.01164

DOI=10.3389/fmicb.2016.01164

ISSN=1664-302X

ABSTRACT=<p><bold>Background:</bold> Microbiological diagnosis of aspergillosis and triazole resistance is limited by poor culture yield. To better estimate this shortcoming, we compared culture and molecular detection of <italic>A. fumigatus</italic> in respiratory samples from French patients at risk for aspergillosis.</p><p><bold>Methods:</bold> A total of 97 respiratory samples including bronchoalveolar lavages (BAL), bronchial aspirates (BA), tracheal aspirates, sputa, pleural fluids, and lung biopsy were collected from 33 patients having invasive aspergillosis (<italic>n</italic> = 12), chronic pulmonary aspergillosis (<italic>n</italic> = 3), allergic bronchopulmonary aspergillosis (<italic>n</italic> = 7), or colonization (<italic>n</italic> = 11) and 28 controls. Each specimen was evaluated by culture, pan-<italic>Aspergillus</italic> qPCR, and CYP51A PCR and sequencing.</p><p><bold>Results:</bold> One <italic>A. flavus</italic> and 19 <italic>A. fumigatus</italic> with one multiazole resistant strain (5.3%) were cultured from 20 samples. Culture positivity was 62.5, 75, 42.9, and 15.8% in ABPA, CPA, IA, and colonized patients, respectively. <italic>Aspergillus</italic> detection rate was significantly higher by pan-<italic>Aspergillus</italic> qPCR than by culture in IA (90.5 vs. 42.9%; <italic>P</italic> &lt; 0.05) and colonization group (73.7 vs. 15.8%; <italic>P</italic> &lt; 0.05). The CYP51A PCR found one TR<sub>34</sub>/L98H along with 5 novel <italic>cyp51A</italic> mutations (4 non-synonymous and 1 promoter mutations), yet no association can be established currently between these novel mutations and azole resistance. The analysis of 11 matched pairs of BA and BAL samples found that 9/11 BA carried greater fungal load than BAL and CYP51A detection was more sensitive in BA than in BAL.</p><p><bold>Conclusion:</bold> Direct molecular detection of <italic>Aspergillus</italic> spp. and azole resistance markers are useful adjunct tools for comprehensive aspergillosis diagnosis. The observed superior diagnostic value of BAs to BAL fluids warrants more in-depth study.</p>