The signs and symptoms of granuloma annulare can vary, depending on the variety:
- Localized. This is the most common type of granuloma annulare. The bump (lesion) borders have a circular or semicircular shape, with a diameter up to 2 inches (5 centimeters). It occurs most commonly on the hands, feet, wrists and ankles of young adults.
- Generalized. Up to 15 percent of the people who have granuloma annulare have lesions over a large portion of their bodies — including the trunk, arms and legs. This type is more likely to be itchy and to affect adults.
- Under the skin. A type that usually affects young children is called subcutaneous granuloma annulare. It produces firm, usually painless, lumps under the skin instead of a rash. The lumps are usually less than 1.4 inches (3.5 centimeters) in diameter and appear on the hands, shins and scalp.
When to see a doctor
Call your doctor if your skin develops reddish bumps (lesions) in ring patterns that don't go away within a few weeks.
No one knows exactly what causes granuloma annulare. But in some people, the condition may be triggered by:
- Animal or insect bites
- Infections, including hepatitis
- Tuberculin skin tests
- Sun exposure
- Other minor injury to the skin
Granuloma annulare is not contagious.
Granuloma annulare is occasionally associated with diabetes or thyroid disease, most often when lesions are numerous or widespread.