Hemophagocytic lymphohistiocytosis presenting with refractory thrombocytopenia after severe burn injury: a case report

Background Hemophagocytic lymphohistiocytosis is a rare but potentially fatal hyperinflammatory syndrome caused by uncontrolled immune activation. Although severe burn injury induces profound immune dysregulation and systemic inflammation, burn-associated hemophagocytic lymphohistiocytosis remains underrecognized because its clinical manifestations often overlap with those of sepsis and critical illness. Case presentation A 50-year-old man sustained flame burns involving 35% of the total body surface area. On day 4, he developed septic shock due to burn wound infection and underwent surgical debridement and skin grafting. On day 9, the platelet count decreased to 14,000/μL and subsequently progressed to transfusion-refractory thrombocytopenia with persistent inflammation. Disseminated intravascular coagulation, drug-induced thrombocytopenia, and heparin-induced thrombocytopenia were considered unlikely. Because hemophagocytic lymphohistiocytosis was suspected, bone marrow aspiration was performed on day 15 and revealed hemophagocytosis. Although the patient did not strictly fulfill the diagnostic criteria, hemophagocytic lymphohistiocytosis was clinically diagnosed based on persistent fever, multilineage cytopenia, hypertriglyceridemia and bone marrow hemophagocytosis. Corticosteroid-based therapy for suspected hemophagocytic lymphohistiocytosis was initiated on day 16, followed by an increase in platelet counts and improvement in inflammatory markers. An additional skin grafting procedure was subsequently performed without recurrence of thrombocytopenia. After recovery from the acute phase of burn injury and satisfactory wound healing, he was transferred to a rehabilitation hospital on day 55. Conclusions Hemophagocytic lymphohistiocytosis may be considered as a differential diagnosis in patients with severe burns who develop progressive or transfusion-refractory thrombocytopenia. When hemophagocytic lymphohistiocytosis is suspected, early bone marrow aspiration may support the clinical diagnosis and facilitate timely therapeutic intervention.