Eosinophilic fasciitis (Shulman’s syndrome) involves inflamed fascia (layer of fibrous tissue below the skin) and muscles of the extremities due to eosinophil (a certain type of white blood cells) infiltration, which causes tenderness and swelling. It is classified as a diffuse connective tissue disease. The arms and forearms are affected more often than are the thighs and legs. Presence on the trunk of the body occurs in approximately 50% of the cases, but the face is usually spared. The etiology of this disease has been linked to aberrant immune responses as well as toxic, environmental, or drug exposures. Another cause is thought to be due to sudden, strenuous physical exertion in an otherwise sedentary person.
Inflammation of muscle fascia, associated with eosinophilia, pain, and swelling.