Symptoms and causes

Symptoms

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.

Causes

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
  • Vaccinations
  • Sun exposure
  • Other minor injury to the skin

Granuloma annulare is not contagious.

Risk factors

Granuloma annulare is occasionally associated with diabetes or thyroid disease, most often when lesions are numerous or widespread.