Hemophagocytic Lymphohistiocytosis Secondary to Dengue Fever.

: Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome often misdiagnosed due to its rarity and overlapping symptoms with sepsis or organ dysfunction. This case report describes a 52-year-old male who developed dengue-induced HLH after traveling to Barbados, presenting with multi-organ failure and laboratory abnormalities, including hyperferritinaemia and elevated IL-2R. Diagnosed via bone marrow biopsy, he was treated with corticosteroids and the IL-1R antagonist anakinra, leading to recovery. Dengue-associated HLH in adults is rare but rising due to increased global dengue incidence. Early recognition and tailored treatment are critical for improved outcomes.

Conclusions: Internists must maintain a high index of suspicion for hemophagocytic lymphohistiocytosis (HLH) in febrile patients with multi-organ dysfunction and hyperferritinaemia.This case addresses the diagnostic and therapeutic voids in adult HLH management, offering a practical framework for internists treating complex cases of infection-triggered hyperinflammatory syndromes.