Epstein-Barr virus-associated haemophagocytic lymphohistiocytosis complicated by neurological involvement in a patient with dermatomyositis: A case report and literature review.

Haemophagocytic lymphohistiocytosis (HLH) is an extremely high mortality condition that can occur at any age and lacks specific diagnostic characteristics. Despite its rarity, HLH is increasingly alarming because of the high mortality rate. It is a systemic hyperinflammatory immune response syndrome associated with abnormal activation of T cells and macrophages, which may be caused by genetic mutations or acquired factors, such as infection, autoimmune condition, and malignancy. Here, we present a fatal case of Epstein-Barr virus-associated HLH complicated by neurological involvement in a patient with dermatomyositis. We describe and discuss the pathological features, classification, and effective treatment options of HLH and discuss separately the special characteristics of Epstein-Barr virus-associated HLH and dermatomyositis-associated HLH.