Disseminated granuloma annulare - Skin
In contrast to other variants of granuloma annulare, the generalized form predominantly affects children younger than 10 and adults older than 40, has a more prolonged course that may be greater than 3 to 4 years, and is more resistant to treatment. Granuloma annulare does not favor any particular ethnicity or region. Disseminated disease occurs in approximately 15% of patients with granuloma annulare, with a greater incidence in females than males.
Although the etiology of granuloma annulare is poorly understood, there are rare reports of associations with infections, systemic diseases, hematologic malignancies, and solid tumor malignancies. In particular, hypothesized infectious associations are tuberculosis, HIV, Epstein-Barr virus, hepatitis B and C virus, and herpes zoster virus. Systemic diseases reported to have a connection with granuloma annulare are type I diabetes and thyroid disease. Chronic stress has been reported as a trigger. There have also been cases of granuloma annulare following trauma or insect bites. Familial cases have led to the hypothesis of an association with HLA phenotypes. While these factors all may be initiators of granuloma annulare, the mechanism of lesion formation has many possibilities. Current hypotheses include a delayed-type hypersensitivity reaction, a cell-mediated immune response, a cytokine-mediated breakdown of connective tissue, or a primary degeneration of connective tissue with an ensuing granulomatous inflammation.
L92.0 – Granuloma annulare
402364005 – Generalized granuloma annulare
- Actinic granuloma produces annular plaques similar to those of granuloma annulare but is specifically located in sun-exposed skin.
- Necrobiosis lipoidica is characterized by shiny red-brown plaques on the lower legs of diabetics that progressively become more yellow and atrophic with time.
- Tinea corporis may manifest as annular, erythematous plaques with surface changes of scaling, crusting, papules, or vesicles in the advancing border. KOH prep will show branching hyphae.
- Erythema migrans is the classic targetoid lesion of Lyme disease that shows concentric rings of erythema with central clearing.
- Erythema annulare centrifugum presents with annular and erythematous plaques with central clearing and a classic trailing scale at the inner rim of the plaque.
- Urticaria may present with annular plaques, but these lesions will be fleeting in nature, lasting less than 24 hours.