Eosinophilic fasciitis

Definition:

A syndrome characterized by tenderness and swelling of the extremities caused by inflammation of the fascia and muscles.

Causes, incidence, and risk factors:

The cause of eosinophilic fasciitis is unknown. There is an infiltration of eosinophils, a type of white blood cell, into the affected fascia and muscles. Eosinophils are associated with allergic-type reactions, but their specific function is largely unknown. The arms, legs, trunk, and face may be affected by joint contractures, muscle weakness, and changes in the overlying skin. The syndrome in some cases appears to be precipitated by strenuous physical activity. Any age may be affected, but most people are between 30 and 60 years old.