This observational study aims to compare immune checkpoint expression in blood samples from patients with invasive fungal infections (IFI) against healthy controls.

Participating sites will screen patients with invasive aspergillosis for eligibility. The investigators will enroll patients with aspergillosis and healthy controls. Patients will be informed by study personnel. Samples for imune phenotyping will be obtained within 7 days after diagnosis of IFI. A bronchoalveolar lavage (BAL) biopsy is taken at initial diagnostic bronchoscopy or other biopsy during surgical debridement whenever applicable and feasible.

The following data items will be collected: Patient characteristics, details on invasive fungal infection (IFI), underlying disease, outcome after 90 days (response, remission, progress, death). All collected data will be interpreted at the end of the study. All patients must agree to participate and sign the informed consent form.

The primary objective is to compare immune checkpoint expression in blood samples from patients with IFI against healthy controls. Exploratively, lymphocytic immune phenotypes in BAL or other biopsy samples from patients with IFI will be assessed. Further, cytotoxic T cell responses in blood samples from patients with IFI shall be investigated and the level of immune checkpoint expression correlated with mortality.

Inclusion Criteria:

• Age ≥18 years
• Proven or probable, incl. PCR, positive IFI along 2019 EORTC/MSG criteria
• Signed ICF

Exclusion Criteria:

• None.

Patients with IFI and healthy controls