Myositis in infiltrative lymphocytosis syndrome: clinicopathological observations and treatment.

Diffuse infiltrative lymphocytosis syndrome (DILS) is characterized by the presence of persistent circulating CD8 lymphocytosis and visceral CD8 lymphocytic infiltration, predominantly in the salivary glands and lungs in a subset of human immunodeficiency virus (HIV) patients. Myositis has been rarely documented in DILS. We report here the histopathological abnormalities and treatment response of an HIV patient with DILS associated myositis. Muscle biopsy revealed features of polymyositis but electron microscopy study showed intranuclear filamentous inclusions of 18 nm diameter, without intracytoplasmic inclusion. Treatment with intravenous immunoglobuline was useful.