IFNG and tuberculosis: Of the participants who considered blood tests essential (Q25, N = 70 responses), 98.6% would request full blood count including complete white cell count; 97.1% clotting tests including PTT, INR, fibrinogen and D dimers, and 90.0% would order immunology tests including ANA, ENA, complement factors, cardiolipin antibodies and ANCA; 42.9% suggested blood tests for adenosine deaminase 2 activity (ADA2) and 41.4% for interferon gamma release assay (IGRA) to exclude tuberculosis (Table 5).