Overcash, Michael D. MPAS, PA-C
Michael D. Overcash is on the clinical faculty at the Medical University of South Carolina in Charleston, practices at Trident Dermatology in North Charleston, S.C., and is department editor of Dermatology Digest. The author has indicated no relationships to disclose relating to the content of this article.
A 50-year-old woman came to the office for evaluation of asymptomatic lesions that appeared on her hands over the past year. She worked at an airplane manufacturing plant and was concerned about contact with chemicals and carbon fibers used in the facility. The lesions failed to clear with application of 1% hydrocortisone or an over-the-counter antifungal cream recommended by her pharmacist. She had significant photodamage on her face, upper chest, and forearms. On her dorsal hands and digits, the provider noted multiple 1- to 4-cm smooth, annular, pink elevated plaques with central clearing, with a background of solar lentigines (Figures 1 and 2).
Palpation of the lesions revealed an indurated, elevated edge, and no tenderness or scale. No lesions were seen on the patient's face or in her mouth, and her nails had no dystrophy or discoloration.
THE LIKELY DIAGNOSIS IS
* cutaneous lupus erythematosus
* tinea corporis
* actinic granuloma
* basal cell carcinoma
The appearance and location of the patient's lesions point to actinic granuloma, a subset of granuloma annulare. Actinic is synonymous with solar, meaning sun-related. Granuloma annulare is benign and asymptomatic, involving grouped papules in an annular configuration. One of the most common types of granuloma annulare involves a localized distribution, for example, on the dorsal or lateral surfaces of the hands or feet.
Because the patient's lesions have no scale and did not respond to topical antifungal cream, tinea corporis is unlikely. A potassium hydroxide (KOH) test could easily be performed to support a lack of dermatophyte infection. Tinea incognito and Majocchi granulomas are caused by application of a topical corticosteroid to a fungal infection, and could be included in the differential. Basal cell carcinoma can present with a raised, rolled border but would not have a clear center.
Cutaneous lupus erythematosus must be considered, as it is often annular, infiltrative, and occurs on sun-exposed skin. A 3-mm punch biopsy was performed and sent to a dermatopathologist for evaluation. Histopathology revealed a granulomatous infiltrate of histiocytes and histiocytic giant cells, with elastophagocytosis, a reaction pattern seen in inflammatory processes in sun-damaged skin.
The presence of elastophagocytosis distinguishes actinic granuloma from granuloma annulare.1 Actinic granuloma is thought to be caused by a cell-mediated immune response to an unknown antigen, or elastotic fibers altered by chronic sun damage.2
Variants of granuloma annulare include:
* Generalized, which is widespread, often affects the trunk and extremities, and is often found in skin folds such as the groin and axillae
* Subcutaneous, which resembles rheumatoid nodules, is often found in children, is painless, and occurs on the scalp and extremities
* Perforating, which usually affects the hands, is associated with scarring, and may hurt or itch
* Atypical, such as photosensitive, facial, or severe granuloma.
Ruling out cutaneous lupus is important, not only because of the similar presentation, but because about 10% of patients with skin-only lupus eventually develop systemic lupus. A dermatopathologist will be able to determine the presence of a perivascular mononuclear cell infiltrate with involvement of the epidermis and appendages.3 A diagnosis of cutaneous lupus warrants serologic evaluation for systemic lupus erythematosus.
Squamous cell carcinoma in situ (Bowen disease) also should be considered in patients with persistent pink plaques on sun-damaged skin.
Treatment No treatment is necessary other than sun protection, and some cases of granuloma annulare resolve spontaneously. Interestingly, granuloma annulare often resolves after it is biopsied, due to an unconfirmed process.4
If the lesions cause pruritus or cosmetic concerns for the patient, ultrapotent topical corticosteroids may be helpful. Intralesional triamcinolone is the most effective option. Topical calcineurin inhibitors such as tacrolimus are an option in cases where atrophy is a concern. Small plaques have been treated with liquid nitrogen or imiquimod, but these treatments can produce significant pain or hypopigmentation. Treatment of disseminated granuloma annulare has been attempted with a large variety of systemic agents, with variable success.
1. Barnhill RL, Goldenhersh MA. Elastophagocytosis: a non-specific reaction pattern associated with inflammatory processes in sun-protected skin. J Cutan Pathol
2. McGrae JD Jr. Actinic granuloma. A clinical, histopathologic, and immunocytochemical study. Arch Dermatol
3. Hood AF, Farmer ER. Histopathology of cutaneous lupus erythematosus. Clin Dermatol
4. Levin NA, Patterson JW, Yao LL, Wilson BB. Resolution of patch-type granuloma annulare lesions after biopsy. J Am Acad Dermatol
© 2014 American Academy of Physician Assistants.