Macrophage activation syndrome as a complication of dermatomyositis: A case report

Macrophage activation syndrome (MAS) can be a fatal complication of rheumatic disorders, which occurs most commonly in patients with systemic juvenile idiopathic arthritis or systemic lupus erythematosus. It has rarely been reported in patients with dermatomyositis. Here, we describe a fatal case of MAS that developed in an adult patient with dermatomyositis.

A 44-year-old woman was admitted to our hospital with fever, generalized rash and muscle weakness. Fifteen days later, the fever persisted after the use of antibiotics, and repeat blood culture was negative. The patient then exhibited a typical Gottron sign and diffuse erythema on the face and neck, which were consistent with a diagnosis of dermatomyositis. The patient exhibited limb muscle strength of 2, and electromyography was suggestive of muscle-derived damage, which also supported a diagnosis of dermatomyositis. In addition, the patient exhibited high serum ferritin level, cytopenia, liver dysfunction, coagulopathy, enlarged spleen and hypertriglyceridemia, all of which are typical manifestations of MAS. The patient was diagnosed with dermatomyositis complicated by MAS. Although a high dose of methylprednisolone was administered for 15 d, the patient's condition continued to deteriorate and central nervous system symptoms developed. Eventually, treatment was discontinued, and the patient died.

MAS is an important, potentially fatal, complication of dermatomyositis. Although MAS is rare in dermatomyositis, it should be considered in the differential diagnosis of an unexplained change of hemoglobin, platelet, fibrinogen, ferritin and triglyceride, which may complicate dermatomyositis.