A Diagnostic Dilemma of Secondary Hemophagocytosis Lymphohistiocytosis in an Elderly Patient.

Hemophagocytic lymphohistiocytosis (HLH) is a rapidly progressive fatal condition. Although well described in the pediatric population, cases of secondary HLH are seen in adolescents and young adults. In the elderly, HLH has been shown to have a poor prognosis. Owing to its varied presentation and multisystemic involvement, diagnosis is often delayed. Due to its high mortality, prompt diagnosis and treatment are crucial. Here we present a case of secondary HLH in a 69-year-old male, who presented with fever for one week. Initial laboratory workup revealed a bicytopenia and elevated creatinine. He was initially treated with broad-spectrum antibiotics; however, a comprehensive infectious workup was negative. CT scan of the abdomen revealed splenomegaly. Further investigations revealed an elevated ferritin and triglycerides. Due to the constellation of findings, he was started on corticosteroids for concerns of HLH. Bone marrow biopsy was obtained, which revealed dysplastic changes and hemophagocytosis, consistent with HLH. This case highlights the diagnostic challenge and prognosis of HLH in the elderly population, suggesting that diagnosis and treatment should not be delayed for histological confirmation.