Active screening of COVID-19-associated pulmonary aspergillosis with serum beta-glucan and endotracheal aspirates galactomannan and fungal culture

Background: Since February 2021 active screening of COVID-19-associated pulmonary aspergillosis (CAPA) has been implemented in our institution.

Objectives: To evaluate CAPA incidence in our centre and evaluate performance of our screening protocol.

Methods: We screened once per week, collecting endotracheal aspirates for fungal culture and galactomannan (GM) and serum for 1,3-ß-D-glucan (BG). In case of positivity (GM more than 4.5, platelia assay, and/or BG >7 pg/ml, wako and/or positive fungal culture), second-level investigations were performed to pursue CAPA diagnosis according to ECMM/ISHAM criteria: bronchoalveolar lavage (BAL) fungal culture and GM, chest computed tomography (CT), serum GM.

Results: A total of 102 patients were screened (median age 64 years, range 39-79; 28 (27.4%) females). Twenty-two patients were diagnosed with CAPA (21%). 12 patients were positive for serum BG, 17 patients were positive for endotracheal aspirates GM and 27 patients were positive for endotracheal aspirates fungal culture. Thirty-two BALs were performed, and 26 patients underwent CT chest. Following the second level investigations 61% of the patients with positive screening tests were diagnosed with CAPA. Serum BG above 20 pg/ml or positive serum GM were always associated with typical CT chest signs of aspergillosis. Compared with 1 single positive test, having 2 positive screening test was significantly more associated with CAPA diagnosis (p = .0004).

Conclusions: Active CAPA screening with serum 1,3-ß-D-glucan and endotracheal aspirates galactomannan and fungal cultures and consequent second level investigations led to high number of CAPA diagnosis. Combining more positive fungal biomarkers was more predictive of CAPA diagnosis.