Granuloma Annulare: Causes and Treatment Options
Causes of Granuloma Annulare
Granuloma annulare is a benign, self-limited inflammatory skin condition with multiple potential triggers, though its exact etiology remains unclear. Common causes and associations include:
- Physical trauma, infections, immunizations, insect bites, and alterations in cell-mediated immune responses may trigger granuloma annulare 1
- Diabetes mellitus has been associated with granuloma annulare, particularly with the disseminated form 2
- Systemic diseases including dyslipidemia and malignancies have been documented in association with granuloma annulare 2
- Rare associations with other autoimmune conditions such as recurrent uveitis have been reported 2
- Purified protein derivative administration has been implicated in some case reports 1
Clinical Presentation
- Localized granuloma annulare typically presents as grouped papules in an annular (ring-shaped) pattern, commonly on the lateral or dorsal surfaces of hands and feet 3
- Disseminated/generalized granuloma annulare involves widespread papular eruptions primarily affecting the trunk, neck, and extremities 2
- Color ranges from flesh-colored to erythematous 3
- Lesions are usually asymptomatic but may be mildly pruritic in some cases 1
- Four main clinical variants exist: localized, generalized, subcutaneous, and perforating 1
Treatment Options
For Localized Granuloma Annulare:
- Mid to high potency topical corticosteroid ointment applied twice daily under occlusion is the first-line treatment for localized disease 4
- Intralesional triamcinolone acetonide (5-10 mg/cc) is recommended for persistent lesions 4
- Topical vitamin D analogs in combination with topical steroids are effective for persistent lesions 4
- Liquid nitrogen cryotherapy may be beneficial for limited lesions 3
- Topical tacrolimus or pimecrolimus can be considered for persistent lesions 4
- Localized disease is generally self-limited and resolves within one to two years, so reassurance may be sufficient in many cases 3
For Generalized/Disseminated Granuloma Annulare:
- Narrowband UVB (TL-01) phototherapy is recommended as first-line therapy for generalized disease due to its effectiveness and favorable long-term safety profile 4
- Photodynamic therapy (PDT) has shown a 52% complete response rate but may be impractical for widespread disease 4
- Systemic therapies for resistant or widespread disease include:
- Dapsone 5, 3
- Retinoids (including isotretinoin) 5, 2
- Niacinamide/nicotinamide 5, 3
- Antimalarials (hydroxychloroquine) 5, 3
- Methotrexate 4, 1
- Psoralen plus ultraviolet A (PUVA) therapy 5
- Fumaric acid esters 5
- Biological agents (etanercept, infliximab, adalimumab) for refractory cases 5
- Oral metronidazole has been reported effective in some cases 1
Treatment Considerations
- Localized disease often resolves spontaneously within 1-2 years, while generalized disease tends to persist longer 3
- There are no well-designed randomized controlled trials for granuloma annulare treatment; recommendations are based on case reports, expert opinion, and pathophysiology 3
- Treatment choice should be guided by disease extent, patient preference, and potential medication side effects 3
- Regular follow-up is necessary to assess treatment response 4
- Consultation with a dermatologist is recommended for disseminated disease due to potential toxicities of systemic agents 3