Granuloma annulare is a skin condition that causes a round, smooth bump. This will become ring-shaped with a center of clear skin. The affected skin can be pink or purple. Since this spot doesn’t peel or itch, it can often go unnoticed. With some people, a wider rash of flesh-colored or purple bumps can develop. Granuloma annulare can spread to other parts of the body before clearing. This is called “generalized” granuloma annulare. Children with this condition may develop, harmless lumps under their skin on the scalp, hands and legs.
Granuloma annulare can form anywhere on the skin, but it’s most likely to appear on the top of the hands, feet or on the elbows and knees. The cause of the condition isn’t known, however it’s believed by dermatologists and researchers that the immune system may be involved. A link between granuloma annulare and HIV, thyroid disease and diabetes. For some, insect bites, sun exposure and skin injuries can trigger granuloma annulare.
Anyone can develop localized granuloma annulare at any age, though it’s most common in females and those younger than 30. Older adults have a higher chance of developing generalized granuloma annulare. Infants rarely get this skin issue.
A board-certified dermatologist can diagnose this issue by examining the skin. If needed some of the infected skin may be scraped off for a biopsy, which involved microscopically examining the skin. A biopsy can help rule out other conditions such as:
A blood test may also be needed to rule out other diseases.