IFNG and lymphopenia: 1. Denial for written informed consent.2. Solid organ malignancy or lymphoma diagnosed the last five years.3. Treatment with oral or intravenous steroids.4. Severe immunodeficiency, neutropenia, history of solid organ and bone marrow transplantation, intake of chemotherapy, primary immunodeficiency, severe lymphopenia and treatment with anti-cytokine therapies.5. Positive IFN-γ Release Assay (IGRA)