Raena Kaur¹, Benjamin Palladino¹, John Dyer¹, Edward Raby^{1, 2} 

¹Department of Infectious Diseases, Fiona Stanley Hospital, WA, Australia
²Department of Microbiology, PathWest, Fiona Stanley Hospital, WA, Australia
 

Inhaling airborne spores of the ubiquitous environmental mold Aspergillus can uncommonly cause a spectrum of pulmonary diseases, of which invasive aspergillosis (IA) is one of the most severe.¹ IA diagnosis is challenging owing to absent or non-specific clinical manifestations, non-pathognomonic radiology, and limited sensitivity of respiratory cultures. Fungal diagnostic advances beyond tissue histopathology and culture-based mycological methods include the non-invasive fungal biomarker galactomannan (GM). GM is produced by the Aspergillus cell wall, and can be tested in serum and bronchoalveolar lavage (BAL) fluid with high sensitivity. Bio-Rad’s Platelia Aspergillus ELISA GM assay is widely used, but several exposure factors including antibiotics, foods and nutrients, blood products, and non-Aspergillus fungi can cause result cross-reaction.^{2, 3}

 

An immunocompetent female with significant vape use experienced hypoxic respiratory failure, with extensive bilateral peribronchial nodular and ground glass densities on chest HRCT. Serum and BAL GM were highly elevated, but further testing including lung cryobiopsy failed to demonstrate Aspergillus. Ultimately her presentation was most compatible with e-cigarette or vaping-associated lung injury (EVALI), however given diagnostic uncertainty we recommended IA treatment. This case highlights ongoing clinical challenges in GM application, particularly in emergent pulmonary pathologies, and consequent ‘erring on the side of caution’ when facing diagnostic dilemmas.

1.       Latgé JP, Chamilos G. Aspergillus fumigatus and Aspergillosis in 2019. Clin Microbiol Rev. 2019;33(1).

2.       Hung YH, Lai HH, Lin HC, Sun KS, Chen CY. Investigating Factors of False-Positive Results of Aspergillus Galactomannan Assay: A Case-Control Study in Intensive Care Units. Front Pharmacol. 2021;12:747280.

3.       Adam O, Aupérin A, Wilquin F, Bourhis J-H, Gachot B, Chachaty E. Reply to Penack et al. and Wu. Clinical Infectious Diseases. 2004;39(9):1402-3.