Eosinophilic fasciitis is a very rare condition in which muscle tissue underneath the skin, called fascia, becomes swollen and thick. Rapid swelling can occur in the hands, arms, legs, and feet. People with this condition have a buildup of eosinophils, a type of white blood cell, in the affected fascia and muscles. The exact cause of this condition is unknown. Corticosteroids and other immune-suppressing medications are used to relieve the symptoms. Eosinophilic fasciitis is similar in appearance to scleroderma. However, in contrast with systemic sclerosis, internal organ involvement in eosinophilic fasciitis is generally absent. Some researchers believe that eosinophilic fasciitis may be a variant of morphea (localized scleroderma).

About 10-20% of people with eosinophilicfasciitis recover spontaneously without treatment. For those who donot, glucocorticoids (0.5–1 mg/kg/d), such as prednisone, are themainstay therapy. Even with treatment, improvement in symptoms can takeweeks or months. Glucocorticoids are successful in treatingeosionophilic fasciitis in over 70% of cases. If glucocorticoids areunsuccessful, methotrexate at low doses(15–25 mg once weekly) is probably the most favored second-linetreatment, especially in people with reddish to purpleish (morphea-like) skin lesions. Other treatment options includeNSAIDs, D-penicillamine, chloroquine, cimetidine, azathioprine,cyclosporin A, infliximab, UVA-1, and bath PUVA.Physical therapy may help improve joint mobility and decrease contractures. Surgical release has been used in some severe cases to manage significant joint contractures.