Aspergillus PCR in Bronchoalveolar Lavage Fluid for the Diagnosis and Prognosis of Aspergillosis in Patients With Hematological and Non-hematological Conditions

Abstract

<b>Objectives:</b> We evaluated the usefulness of an <i>Aspergillus fumigatus</i> quantitative PCR assay performed in bronchoalveolar lavage fluid (BAL) for the diagnosis and prognosis of both invasive and non-invasive aspergillosis. <b>Methods:</b> This 4-year retrospective study involved 613 at-risk patients who had either hematological disorders or other immunosuppressive conditions, notably solid organ transplants. Thirty-five patients had proven/probable aspergillosis and thirteen had chronic non-invasive aspergillosis. We compared PCR, galactomannan index and mycological analysis of BAL. <b>Results:</b> For invasive aspergillosis (IA), PCR performed in BAL yielded 88.6% sensitivity and 95.5% specificity. Comparatively, galactomannan index and mycological examination yielded only 56.3 and 63.6% sensitivity and 97.6 and 94.5% specificity, respectively. Considering the 13 chronic aspergillosis cases, PCR, galactomannan index and mycological examination yielded 76.9, 15.4, and 84.6% sensitivity and 92.2, 94.9, and 93% specificity, respectively. Fungal load in BAL evaluated by PCR was able to discriminate between aspergillosis and contamination, but not between invasive and non-invasive forms. Finally, fungal load was predictive of 90-day mortality, with 23.1% mortality for patients with less than 500 copies/mL versus 68.4% for patients above that cut-off (<i>p</i> < 0.05). <b>Conclusion:</b> Our results indicate that <i>Aspergillus</i> PCR in BAL is of particular interest for both the diagnosis and the prognosis of IA. It is likewise an interesting tool for the diagnosis of non-invasive forms.