Haemophagocytic Lymphohistiocytosis in an Elderly Patient after Recent Cardiac Surgery

INTRODUCTION: The underlying pathophysiology of haemophagocytic lymphohistiocytosis (HLH) is characterised by excessive inflammation and tissue destruction secondary to abnormal immune activation. The term primary HLH refers to a genetic abnormality that predisposes to the condition whereas secondary refers to HLH being triggered by an underlying condition such as infection (often Epstein Barr Virus), autoimmune, or neoplastic disease. Its variable clinical presentation poses an obstacle to prompt diagnosis in the elderly patient. CASE: A 70-year-old Caucasian man was admitted to hospital from a convalescence center with symptoms of fatigue, fever, decreased oral intake, and increasing shortness of breath on exertion. The patient was three weeks after coronary artery bypass grafting. Over the next two weeks, the patient continued to deteriorate both clinically and biochemically. The patient met criteria for haemophagocytic lymphohistiocytosis, likely driven by EBV infection. Bone marrow biopsy supported the diagnosis with evidence of active phagocytosis. The patient was commenced on high-dose dexamethasone and reviewed by haematology with further molecular testing confirming the diagnosis. Discussion. LH is becoming more common in older patients. We propose that new guidelines be developed to aid its prompt diagnosis in this age group.