Granuloma annulare (GA) is a skin condition that affects people of all ages and tends to grow on the skin over the joints, especially on the back of the hands, knuckles, and fingers.
Granuloma annulare appears as one or more smooth, firm, reddish, ring-shaped bumps. Sometimes the bumps will cluster into a ring-shaped growth with depressed centers. There are two types: disseminated GA, a type of GA where there are multiple widespread lesions on the body, and subcutaneous GA, which appears as rubbery lumps on the skin and most often occurs in children.
The exact cause of GA is unknown. Most people with GA are otherwise healthy. Localized GA can be associated with autoimmune inflammation of the thyroid gland, while disseminated GA is associated with diabetes, elevated blood levels of fat and cholesterol, and in rarer cases lymphoma, internal tumors, and HIV infection.
GA is likely to resolve on its own over the span of many months but sometimes it can persist for years. Nevertheless, GA can be located in cosmetically sensitive locations on the body. A health care professional may initiate some of the following medications:
- Anti-inflammatory agents: This includes the use of topical steroid creams and ointments as well as steroid injections into the GA lesions. Other anti-inflammatory agents include topical calcineurin inhibitors (tacrolimus and pimecrolimus).
- Antibiotics: Although GA is not due to infection, antibiotics can have an anti-inflammatory effect.
- Medications that alter the immune system may be used as treatments. Some examples include methotrexate, hydroxychloroquine, dapsone, cyclosporine, and the tumor necrosis factors inhibitors, such as adalimumab and infliximab.
- Cryotherapy with liquid nitrogen may be applied to the lesions.
- Lasers may be used to treat GA.[1
1. Verne SH, Kennedy J, Falto-Aizpurua LA, et al. Laser treatment of granuloma annulare: a review. Int J Dermatol.2016;55(4):376-381; PMID: 26474922.