Granuloma annulare (GA) is a long-term (chronic) skin disease consisting of a rash with reddish bumps arranged in a circle or ring. GA most often affects children and young adults. It is slightly more common in girls. The condition is usually seen in otherwise healthy people. Occasionally, it may be associated with diabetes or thyroid disease. Its cause is unknown.
GA is usually asymptomatic, but the rash may be slightly itchy. Patients usually notice a ring of small, firm bumps (papules) over the backs of the forearms, hands or feet. Occasionally, multiple rings may be found. Rarely, GA may appear as a firm nodule under the skin of the arms or legs.
Your doctor may consider the diagnosis of fungal infection when looking at your skin. A skin scraping and KOH test can be used to tell the difference between the two conditions. A skin biopsy may also be necessary to confirm the diagnosis of GA.
Because GA is usually asymptomatic, treatment may not be necessary except for cosmetic reasons. Strong topical steroid creams or ointments are sometimes used to speed the disappearance of the lesions. Injections of steroids directly into the rings may also be effective. Some physicians may choose to freeze the lesions with liquid nitrogen. In severe cases, ultraviolet light therapy (PUVA) or oral medications may be needed.
Most lesions of GA disappear with no treatment within two years. Sometimes, however, the rings can remain for many years. The appearance of new rings years later is not uncommon.