Granuloma annulare is a chronic skin disorder in which small, firm, raised bumps appear and spread out to form a ring with normal or slightly sunken skin in the center.
(See also Overview of Hypersensitivity and Reactive Skin Disorders.)
Granuloma annulare may be the result of an immune system reaction.
People may have one ring or several and colors vary.
The diagnosis is usually based on the appearance of the skin and can be confirmed with a skin biopsy.
Granuloma annulare usually heals without treatment.
The cause of granuloma annulare is not clear, but doctors suspect it is the result of an immune system reaction. Many disorders, infections, medication use, and environmental factors have been noted in people who have granuloma annulare, but having granuloma annulare does not mean that another disorder is present.
Granuloma annulare occurs twice as often in women as in men.
Symptoms of Granuloma Annulare
The bumps are usually red but may be slightly bluish, yellowish tan, or the color of the surrounding skin. Bumps may appear to be lighter than the surrounding skin in people who have dark skin.
A person may have one bump or several. The bumps may be tender but usually cause no pain or itching. They most often form on the feet, legs, hands, or fingers of children and adults.
The bumps often expand outwardly to form rings. The center of each ring may be clear or be slightly sunken and sometimes pale or light brown. In some people, the rings become widespread.
Diagnosis of Granuloma Annulare
A doctor's evaluation
Sometimes a skin biopsy
Doctors usually diagnose granuloma annulare by its appearance.
A sample of skin may be removed and examined under a microscope (called a skin biopsy) to confirm the diagnosis.
Treatment of Granuloma Annulare
For widespread rings, sometimes other medications
Most often, granuloma annulare heals without any treatment, so people who have no symptoms usually require no treatment. However, healing may take years.
Phototherapy (exposure to ultraviolet light) and cryotherapy (exposure to cold) are other treatments that may also be used.
