Disseminated eruptive interstitial granuloma annulare mimicking lichen nitidus

ARTICLE

ejd.2011.1417

Auteur(s) : Taner Tanyildizi, Sevgi Akarsu sevgi.akarsu@deu.edu.tr, Turna İlknur, Banu Lebe, Emel Fetil

Department of Dermatology, Dokuz Eylul University Faculty of Medicine, 35340 Inciraltý Izmir, Turkey

Granuloma annulare (GA) is a benign, inflammatory and usually self-limited cutaneous disease. Its classic clinical presentation is a slightly erythematous papule that tends to expand into an annular plaque with a papular border. However, several morphologic forms have been reported including localized, disseminated, linear, nodular, pustular, perforating, lichenoid and subcutaneous. Numerous micropapules, as well as lichenoid papules in some cases, have only rarely been reported in the literature [1-5]. The various types of GA share similar histologic findings that are characterized by necrobiotic collagen associated with an infiltration of histiocytes, lymphocytes and a variable number of multinucleated giant cells in superficial and mid-dermis. Additionally, three histopathologic patterns including necrobiotic granulomas, interstitial/incomplete form, and granulomas of sarcoidal or tuberculoid type, can be seen in GA. In interstitial/incomplete GA, histopathologic findings are subtle. In this form, increased numbers of histiocytes and lymphocytes, located in the perivascular area and between collagen bundles, are seen in the dermis, although there is no necrobiosis [6]. Here, we present a rare case of disseminated interstitial GA presenting with an extremely eruptive manifestation characterized by discrete skin-coloured and lichenoid papules.

A 45-year-old man visited our hospital with a 5-month history of multiple, occasionally pruritic, papular skin lesions, which initially began on his hands and gradually spread to his upper extremities and trunk. He denied any history of drug intake and his family history was unremarkable. Clinical examination revealed widespread, symmetrically distributed, skin-coloured to slightly erythematous, minute, 1- to 2-mm discrete papules on the upper trunk and extremities. The colour of the papular lesions on the upper back and chest, shoulders, and the extensor surfaces of the proximal arms and legs was mostly skin-coloured, but violaceous erythema was found in lesions on the dorsal hands and feet, wrists and ankles (figure 1A).

Hematologic and biochemical investigations revealed no abnormalities. Tests for hepatitis B virus, hepatitis C virus and HIV were negative. Blood glucose level and an oral glucose tolerance test were also normal. We made the differential diagnosis of lichen nitidus primarily, but also sarcoidosis and other lichenoid dermatoses such as lichen planus and lichenoid drug eruption were considered. The skin biopsies taken from both skin-coloured and erythematous papules revealed dermal interstitial infiltration with CD68-positive and S100-negative histiocytes between collagen bundles, and focal myxoid degeneration in collagen was detected by Alcian blue stain. There were no formed areas of necrobiosis. These histopathological findings were consistent with interstitial/incomplete GA (figure 1B). The patient refused oral PUVA therapy, and so we opted for treatment with acitretin at 50 mg/day. Because this therapeutic option yielded no marked result after 3 months, acitretin treatment was discontinued. Subsequently, he did not accept another therapy and was lost to follow-up.

Disseminated GA, which is a rare skin condition, represents 8.5-15% of all cases of GA diagnosed. It was reported to be differentiated from the localized form by its morphology, a wide distribution of lesions, a later age of onset, a protracted course and a poor response with therapy, as in our case. In most cases, it exhibits variously sized individual lesions from one case to another. It consists of occasionally pruritic, numerous skin-coloured to erythematous papules with or without annular configuration, which occur on the trunk and extremities [1-3, 5]. Disseminated eruptive GA is well-known but is rare in the form of micropapules. Recently, some cases of disseminated GA presenting with hundreds of symmetrically scattered, skin-coloured to slightly erythematous micropapules have been reported in association with diabetes mellitus, HIV infection and chronic hepatitis B virus infection [1-3]. There was no definitive causative factor for the existence of GA in our case. In this case of disseminated GA with a distinct clinical presentation, lesions primarily mimic lichen nitidus; however, the histopathology is characteristic for interstitial or “incomplete” GA.

Disclosure

Financial support: none. Conflict of interest: none.

References

1. Ine K, Kabashima K, Koga C, Kobayashi M, Tokura Y, Kabashima K. Eruptive generalized granuloma annulare presenting with numerous micropapules. Int J Dermatol 2010 ; 49 : 104-105.

2. Marzano AV, Ramoni S, Alessi E, Caputo R. Generalized granuloma annulare and eruptive folliculitis in an HIV-positive man: resolution after antiretroviral therapy. J Eur Acad Dermatol Venereol 2007 ; 21 : 1114-1116.

3. Ma HJ, Zhu WY, Yue X.Z. Generalized granuloma annulare associated with chronic hepatitis B virus infection. J Eur Acad Dermatol Venereol 2006 ; 20 : 186-189.

4. Dimitrowa J, Obreschkowa E, Al Jraivi S.S. Follicular lichenoid generalized granuloma annulare. Z Hautkr 1984 ; 59 : 421-425.

5. Grupper C, Elalouf C. Generalized lichenoid papular granuloma annulare. Bull Soc Fr Dermatol Syphiligr 1968 ; 75 : 774-777.

6. Werchau S, Enk A, Hartmann M. Generalized interstitial granuloma annulare-response to adalimumab. Int J Dermatol 2010 ; 49 : 457-460.