Kinetics of anti-Aspergillus spp. IgG antibodies in COVID-19-associated pulmonary aspergillosis.

COVID-19-associated pulmonary aspergillosis (CAPA) is a recognized fungal superinfection, but diagnosis remains difficult due to non-specific clinical and radiological findings. While anti-Aspergillus spp. IgG antibodies (AspAb) are used for chronic aspergillosis diagnosis, their role in this context is unclear. We described AspAb kinetics in CAPA patients hospitalized in intensive care unit (ICU). We performed a retrospective study at Lille University Hospital from February 2020 to December 2021, enrolling ICU SARS-CoV-2 patients. Patients were included if they had at least one positive mycological marker-direct examination, culture, galactomannan antigen (GM) or Aspergillus fumigatus qPCR in bronchoalveolar lavage and/or serum-along with clinical and radiological findings consistent with CAPA, as defined by the 2020 European Confederation of Medical Mycology and the International Society for Human and Animal Mycology consensus criteria. Among 898 patients, 95 (10.6%) had at least one positive mycological marker; 47 fulfilled CAPA criteria (5.2%), and 43 had at least one AspAb measurement. One-quarter of CAPA patients (23.3%, 10 patients) had at least one positive AspAb measurement (one of whom had only one measurement). Among AspAb-positive patients, seven (70.0%) seroconverted a mean of 8.3 days (standard deviation, 8.5) after CAPA diagnosis; one had documented positivity prior to hospitalization. Seven patients (70.0%) reached AspAb rate ≥ 80 AU/ml. These results are the first observed in CAPA patients and need to be confirmed in a larger cohort of non-neutropenic patients hospitalized in ICU with viral pneumonia.