Table 3.

Diagnostic Methods Used for the Diagnosis of CAPA/IAPA. Advantages and Disadvantages.

Diagnostic Test	Comments for CAPA Patients	Advantages	Disadvantages
Lung biopsy	Post-mortem CT-guided biopsies have been used as an alternative to necropsy	Provides definitive CAPA/IAPA diagnosis	High risk of complications
BAL with FBC	In the first wave, practically dismissed due to risk to health personnel. Rarely used during the first wave due to risk to health personnel.	Visualization of trachea and bronchi BAL GM, LFD, and PCR Directed sample	Aerosol generation Potentially poor tolerance in some patients
Not bronchoscopic lavage Non-bronchoscopic lavage	Proposed as an alternative to BAL	Obtains sample from lower respiratory tract. Validated technique for VAP Closed technique	Not well validated for CAPA/IAPA Not well validated for GM/PCR Blind sample
Tracheal aspirate	Colonization in patients with COVID-19?	Easy to perform in MV patients	Sample is less representative of the lower respiratory tract Not validated for biomarkers
Sputum	Colonization in patients with COVID-19?	Easy to perform on all patients	Sample is less representative of the lower respiratory tract Not validated for biomarkers
Serum	Frequently negative in CAPA	Allows GM, LFD, 1-3-β-D-glucan, and PCR Easily obtained	1-3-β-D-glucan results not specific

BAL, bronchoalveolar lavage; GM, galactomannan; LFD, lateral flow device test; VAP, ventilator-associated pneumonia; MV, mechanical ventilation; PCR, polymerase chain reaction.