Sarcoidal Variant of Granuloma Annulare: An Unusual Presentation
Year: 2025
Type: article
Study design: Case Report
Abstract: Sir, Granuloma annulare (GA) is a benign, inflammatory granulomatous skin disease of unknown etiology. It typically presents in two variants: localized and generalized.[1] Localized GA typically presents as clusters of small, skin-colored to erythematous papules that gradually coalesce to form annular plaques. These lesions are usually asymptomatic or mildly pruritic. Common sites of involvement include the dorsum of the hands, elbows, and feet.[2] On the other hand, generalized GA extends beyond these typical locations affecting larger areas of the body and, in some cases, the entire body. Histopathologically, GA exhibits three diverse patterns – An infiltrative pattern, a palisading granuloma pattern, and a sarcoidal granuloma pattern. The infiltrative pattern is the most frequently encountered, in this pattern, there is an infiltration of inflammatory cells within the dermis.[1,2] The sarcoidal granuloma pattern is the rarest. We describe here a biopsy-proven case of GA (Sarcoidal variant) in a 73-year-old female. The patient presented with a history of insidious onset, asymptomatic skin lesions that had been developing over 8–9 months. Her lesions initially appeared on the nose and gradually extended to involve her back and extremities. She had no history of systemic complaints or any known comorbidities. Cutaneous examination revealed erythematous infiltrated papules and plaques over the back, and bilateral lower limbs, predominantly over the shins and ankles [Figures 1 and 2]. Few lesions over the forearms had annular morphology [Figures 3 and 4]. The rest of the mucocutaneous examination revealed no abnormality. The patient was initially started on oral steroids, tablet ivermectin, and emollients. Considering the clinical features of the patient, we suspected sarcoidosis and GA as differential diagnoses. To confirm the diagnosis, a 4 mm punch biopsy was taken from a skin lesion on her right forearm and was sent for a histopathological examination.Figure 1: Clinical photograph showing erythematous infiltrated papules over the noseFigure 2: Clinical photograph showing erythematous papules coalescing to form plaques over the medial aspect of the left footFigure 3: Clinical photograph showing posttreatment - postinflammatory hyperpigmentation over the noseFigure 4: Clinical photograph showing erythematous papules arranged in annular pattern (site of biopsy)The biopsy revealed a sarcoidal granuloma in the superficial dermis surrounding a focus of mucin deposition and incomplete collagen deposition [Figures 5-7]. The granuloma was comprised lymphocytes, histiocytes, and giant cells of the Langerhans type [Figure 8]. The overlying epidermis was flattened with focal parakeratosis, and the rest of the dermis showed a moderate superficial and interstitial lymphohistiocytic infiltrate [Figure 5]. This histopathology is consistent with sarcoidal variant of GA. We initiated the treatment with tablet hydroxychloroquine (300 mg) and mometasone furoate cream for the initial month. At present, the patient is maintained on tablet hydroxychloroquine (200 mg) and tacrolimus ointment.Figure 5: Histopathology picture showing sarcoidal granuloma in the superficial dermis around the focus of mucin deposition and incomplete collagen degeneration, Magnification Scanner view (4X)Figure 6: High power PAS stain showing granuloma, Magnification 40 XFigure 7: Special stain showing foci of necrobiosis, Magnification 10 XFigure 8: High power H and E, Magnification 10 XThe sarcoidal variant of GA is particularly intriguing. It often resembles systemic sarcoidosis, a multisystem granulomatous disorder that can affect various organs, including the lungs, skin, and eyes. Clinically, sarcoidal GA may present as erythematous annular or arc-shaped plaques, much like sarcoidosis. However, it is crucial to differentiate the two, as systemic sarcoidosis can have systemic involvement, whereas GA remains localized to the skin.[3] The basic pathology of GA and sarcoidosis is mononuclear histiocytic cellular reactions. Sarcoidal GA displays noncaseating granulomas consisting of epithelioid histiocytes. Moreover, there’s an increased deposition of mucin between collagen bundles, a unique feature not seen in systemic sarcoidosis. The absence of asteroid or giant cell inclusions further differentiates sarcoidal GA from systemic sarcoidosis.[1,4] Therefore, it is important to be cognizant of this histologic pattern that may be mistaken for cutaneous sarcoidosis. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Authors’ contributions Literature search: V.R.S, S.R.D; Data acquisition: V.R.S, S.R.D; Manuscript preparation: V.R.S, S.R.D; Manuscript editing: V.R.S, S.R.D; Manuscript review: V.R.S, S.R.D. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.
Source: Clinical Dermatology Review
Authors: Vidyadhar R Sardesai, Shimoni Rahul Doshi
Institution: Bharati Vidyapeeth (Deemed to be University)
Language: English
Topic: Skin Diseases and Diabetes
Subfield: Dermatology
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W4409185652