Eosinophilic fasciitis is a rare disorder in which the skin of the arms and legs becomes painfully inflamed and swollen and gradually hardens.
The word eosinophilic refers to the initially high blood levels of a type of white blood cell called eosinophils. The word fasciitis refers to inflammation of the fascia, which is the tough fibrous tissue that lies beneath the skin.
The cause of eosinophilic fasciitis is unknown. The disorder occurs mainly in men aged 40 to 50, but it may occur in women and children.
The usual initial symptoms are pain, swelling, and inflammation of the skin, particularly over the inside of the arms and the front of the legs. The skin of the face, chest, and abdomen may occasionally be affected also. In contrast to systemic sclerosis, the skin of the feet and hands is not affected and Raynaud's syndrome does not occur.
Symptoms may first be noticed after strenuous physical activity. Symptoms usually progress gradually. After weeks, the inflamed skin begins to harden, eventually acquiring a texture similar to an orange peel.
As the skin gradually hardens, the arms and legs become difficult to move. Eventually, the arms and legs may become stuck in unusual positions. Weight loss and fatigue are common. Muscle strength does not usually decrease, but muscle and joint pain may occur. Rarely, if the arms are involved, the person may develop carpal tunnel syndrome (see Hand Disorders: Carpal Tunnel Syndrome).
Sometimes, the numbers of red blood cells and platelets in the bloodstream become very low, resulting in fatigue and a tendency to bleed easily.
A doctor suspects eosinophilic fasciitis because of its typical symptoms. The number of eosinophils is increased in the blood, as is the erythrocyte sedimentation rate (ESR). This increase indicates inflammation.
The diagnosis is confirmed by taking a biopsy of affected skin and the tissues underneath it (the fascia). The biopsy sample must include all skin layers down to the muscle. Magnetic resonance imaging (MRI) can also help make the diagnosis but is not as conclusive as muscle biopsy.
Prognosis and Treatment
The long-term outlook is unknown.
Most people respond rapidly to high doses of corticosteroids. Treatment should be started as early as possible to prevent scarring, tissue loss (atrophy), and contractures. Corticosteroids may not reverse atrophied and scarred tissue. Doses are gradually reduced, but corticosteroids may need to be continued at low levels for 2 to 5 years. For people who cannot use corticosteroids or do not fully respond to corticosteroids, other drugs (for example, hydroxychloroquine or cyclosporine) can be tried.
Monitoring with blood tests is advised because the occasional person develops another blood disorder.
Last full review/revision February 2008 by Rula A. Hajj-ali, MD