Summary
Definition
Granuloma annulare (GA) is an uncommon benign condition of unknown etiology.[1] Lesions are typically described as dermal papules, which coalesce to form rings, and may be skin-colored, pink, or violaceous; commonly found on the back of hands, ankles, knees, and elbows.[Figure caption and citation for the preceding image starts]: Classic localized granuloma annulareFrom the collection of Susmita Mukherjee, BSc, MBBS, MRCP; used with permission [Citation ends].
A number of clinical variants exist.[2] Histology is characteristic. Most cases are self-limited.[3]
History and exam
Key diagnostic factors
- asymptomatic grouped annular pink or flesh-colored dermal papules
Other diagnostic factors
- flesh-colored, pink, or brown macules or small papules
- soft-tissue nodules
- perforating papules, crusting or ulcerated lesions
- erythematous patches
Risk factors
- diabetes mellitus
- hematologic malignancy
- herpes zoster
- HIV
- hepatitis
- hyperlipidemia
- thyroid disease
- medications
Diagnostic investigations
1st investigations to order
- clinical diagnosis
Investigations to consider
- skin biopsy
- fasting blood sugar
- thyroid function tests
- lipid screening
- hepatitis screen
- HIV testing
Treatment algorithm
localized variant (classic annular rash)
generalized variant (widespread macular rash)
perforating variant (crusted or ulcerated lesion)
subcutaneous variant (soft nodule)
patch variant (erythematous plaques)
Contributors
Authors
Misha Rosenbach, MD
Associate Professor
Dermatology and Internal Medicine
University of Pennsylvania
Philadelphia
PA
Disclosures
MR has received consulting fees from Merck, aTyr Pharma, and Processa Pharma, not related to granuloma annulare. He has received grant support from Processa Pharma, not related to granuloma annulare. MR has received salary support from the AMA/JAMA for his role at JAMA Dermatology as Deputy Editor. MR is an author of references cited in this topic.
Acknowledgements
Dr Misha Rosenbach would like to gratefully acknowledge Dr Susmita Mukherjee, a previous contributor to this topic. SM declares that she has no competing interests.
Peer reviewers
Aisha Sethi, MD
Assistant Professor of Medicine
Associate Residency Program Director
University of Chicago
Chicago
IL
Disclosures
AS declares that she has no competing interests.
Robert Herd, MSc, MD, FRCP
Consultant Dermatologist
Department of Dermatology
Nuffield Hospital
Glasgow
UK
Disclosures
RH declares that he has no competing interests.
Brenda L. Pellicane, MD
Dermatologist
Wayne State University School of Medicine
Department of Dermatology
Detroit
MI
Disclosures
BLP declares that she has no competing interests.
Differentials
- Annular lichen planus
- Dermatophyte infections
- Mycosis fungoides
More Differentials
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