Diagnosis of invasive pulmonary aspergillosis (IPA) is challenging. The objective of the study was to assess the value of microbiological tests to the diagnosis of IPA in the absence of non-specific radiological data. A retrospective study of 23 patients with suspicion of IPA and positivity of some microbiological diagnostic tests was performed. These tests included conventional microbiological culture, detection of Aspergillus galactomannan (GM) antigen and in some patients (1 → 3)-β-D-glucan (BDG) and Aspergillus fumigatus DNA using the LightCycler® SeptiFast test. In 10 patients with hematological malignancy, 6 cases were considered 'probable' and 4 'non-classifiable.' In 8 patients with chronic lung disease, 7 cases were classified as 'probable' and 1 as 'proven,' and in 5 patients with prolonged ICU stay (>7 days), there were 2 'proven' cases, 2 'non-classifiable' and 1 putative case. Microbiological culture was positive in 17 cases and 18 Aspergillus spp. were isolated (one mixed culture). A. fumigatus was the most frequent (44.4%) followed by A. tubingensis. The Aspergillus galactomannan (GM) antigen assay was positive in 21 cases (91.3%). The GM antigen and the (1 → 3)-β-D-glucan (BDG) assays were both performed in 12 cases (52.2%), being positive in 9. The SeptiFast test was performed in 7 patients, being positive in 4. In patients with non-classifiable pulmonary aspergillosis and one or more positive microbiological tests, radiological criteria may not be considered a limiting factor for the diagnosis of IPA.
Keywords: (1 → 3)-β-D-glucan; Chronic lung disease; Galactomannan antigen; Hematological malignancy; Invasive pulmonary aspergillosis; Microbiological culture; Prolonged ICU stay; SeptiFast test.