A Rare Case of Haemophagocytic Lymphohistiocytosis

Abstract Haemophagocytic lymphohistiocytosis (HLH) is an uncommon, life-threatening hyperinflammatory syndrome caused by severe cytokinemia, due to an excessively stimulated but ineffective immune process. Early recognition of HLH remains challenging due to its generic presenting symptoms that might lead to misdiagnosis of numerous disorders. This case is linked to an infection with hepatitis A. As HLH overlaps with hepatitis A infection, it was misdiagnosed as hepatitis A alone during the time of admission. As a result, delayed diagnosis and treatment can lead to poor outcomes. Here, we present a case of acute hepatitis A virus infection related to HLH, manifested with splenomegaly, pancytopenia, hyperferritinemia and haemophagocytosis in the bone marrow aspiration. In addition, the patient also experienced a persistent fever. This report contributes to the literature on HLH, emphasising the importance of documenting the rare case to enhance our understanding of this complex disorder. By sharing our case, it aims to shed light on the complexities of HLH in adults, exploring its clinical manifestations, diagnostic approaches and treatment strategies to improve recognition and management of this devastating disease.