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CMAJ
CMAJ
9711805
CMAJ : Canadian Medical Association Journal
0820-3946
1488-2329
CMA Impact Inc.

10.1503/cmaj.231728
196e1013
Practice
Clinical Images
Generalized granuloma annulare
Lobo Carol MD
Kaimal Sowmya MD
Department of Dermatology, St John’s Medical College, Bangalore, India.
Correspondence to: Carol Lobo, carol.lobo@stjohns.in
9 9 2024
09 9 2024
196 29 E1013E1013
© 2024 CMA Impact Inc. or its licensors
2024
https://creativecommons.org/licenses/by-nc-nd/4.0/ This is an Open Access article distributed in accordance with the terms of the Creative Commons Attribution (CC BY-NC-ND 4.0) licence, which permits use, distribution and reproduction in any medium, provided that the original publication is properly cited, the use is noncommercial (i.e., research or educational use), and no modifications or adaptations are made. See: https://creativecommons.org/licenses/by-nc-nd/4.0/
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pmcA 57-year-old woman with no known comorbidities presented to our dermatology clinic with a 6-month history of asymptomatic lesions on her upper back and upper limbs. Examination revealed well-defined, annular, non-scaly plaques with raised erythematous borders and central clearing over the dorsum of her hands, arms, forearms, and upper back in a predominantly photo-distributed pattern (Figure 1). Histopathology showed central necrobiotic collagen surrounded by dermal histiocytic infiltrate in a palisaded arrangement, with mucin deposition, indicative of generalized granuloma annulare. We prescribed topical clobetasol propionate (0.05%) cream and the lesions improved by around 50% after 8 weeks of treatment.

Figure 1: Annular plaques on (A, B) the dorsum of the hands and (C) forearm of a 57-year-old woman with generalized granuloma annulare, as well as (D) well defined annular plaques on her upper back.

Granuloma annulare is an inflammatory dermatosis that affects people of all ages, particularly females, with an annual incidence of 37.9 per 100 000 people.1 Generalized granuloma annulare accounts for 15% of cases and typically manifests as erythematous or skin-coloured annular plaques with a raised, rope-like border and central clearing, predominantly affecting the trunk and extremities. Localized granuloma annulare is the most common variant. Other variants include perforating, subcutaneous, patch, papular, photo-distributed, and drug-induced granuloma annulare. Potential triggers include drug exposure and viral infections. Reported associations include diabetes, malignancy, dyslipidemia, hypothyroidism, and genetic predisposition (i.e., human leukocyte antigen [HLA] B35 in generalized variant).2 Patients should be investigated for these conditions as clinically indicated.

Differential diagnoses for granuloma annulare vary based on the clinical variant. Isolated annular lesions may be attributed to tinea corporis, sarcoidosis, annular lichen planus, and erythema annulare centrifugum. Tinea corporis is characterized by annular scaly plaques with central clearing and presence of hyphae on potassium hydroxide mount. Sarcoidosis presents as skin-coloured papules and annular plaques with characteristic features on pathology. Annular lichen planus presents with violaceous pruritic papules that often involve the genitalia. Erythema annulare centrifugum typically presents with a trailing scale and distinctive histopathological features. Diagnosis is usually clinical and can be supported by biopsy when there is diagnostic uncertainty. When granuloma annulare does not resolve spontaneously, treatment can be challenging. Options include potent topical steroids, intralesional corticosteroids, and calcineurin inhibitors. In extensive disease, oral retinoids, methotrexate, phototherapy, and, more recently, tofacitinib have been found to be beneficial.3

Competing interests: None declared.

This article has been peer reviewed.

The authors have obtained patient consent.
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References

1 Barbieri JS Rodriguez O Rosenbach M . Incidence and prevalence of granuloma annulare in the United States. JAMA Dermatol 2021;157 :824–30.34106215
2 Piette EW Rosenbach M . Granuloma annulare: clinical and histologic variants, epidemiology, and genetics. J Am Acad Dermatol 2016;75 :457–65.27543209
3 Joshi TP Duvic M . Granuloma annulare: an updated review of epidemiology, pathogenesis, and treatment options. Am J Clin Dermatol 2022;23 :37–50.34495491
