ABSTRACT
Hemophagocytic Lymphohistiocytosis (HLH) is a rare but life-threatening disease that can occur either as a primary condition or as a consequence of a variety of triggers, including infectious diseases. Here we present a case of secondary HLH triggered by systemic Mycobacterium tuberculosis infection in a 59-year-old immunocompromised Hairy Cell Leukemia and previous SARS-CoV2 infected patient. This case report underlines the role of Etoposide-based chemotherapy in treating the severe inflammation that is the defining factor of HLH, suggesting how, even when such therapy is not effective, it may still give the clinicians time to identify the underlying condition and start the appropriate targeted therapy. Moreover, it gives insight on our decision to treat the underlying haematological condition with a BRAF-targeted therapy rather than purine analog-based chemotherapy to reduce the risk of future severe infections.