Granuloma annulare is a fairly common chronic skin condition that consists of one or more ring-shaped patches with pink or purple bumps or papules.
Granuloma annulare can often affect bony areas including backs of hands, elbows or ankles. The patches can feel like firm bumps on the skin but can appear flat. It can cause some mild itching as the patches form at first.
Image: Granuloma annulare on the leg.
The condition mainly affects children and young adults, but can occur at any age.
There is no cure for granuloma annulare, but it usually clears up within two years.
What causes granuloma annulare?
The cause is unknown but some forms of the condition are linked to diabetes or thyroid disease. It is not infectious, caused by allergies or inherited.
How is granuloma annulare diagnosed?
The condition will be diagnosed by a doctor or dermatologist by examining the rash at first. A skin biopsy may be arranged to confirm the diagnosis.
How is granuloma annulare treated?
There is no effective treatment for granuloma annulare. Steroid creams, ointments or injections may help with troublesome areas.
Light therapy called PUVA may help people with widespread patches. This involves taking a drug called psoralen then having ultraviolet A light treatment.