Subcutaneous Granuloma Annulare: A Systematic Review on Current Treatments

Subcutaneous Granuloma Annulare (SGA) is a rare subset of Granuloma Annulare (GA), presenting most often in female children and young adults as a benign, nodular lesion. Etiology is unknown but can be linked to stress, immunologic disorders, connective tissue diseases and diabetes. We searched Scopus, PubMed, Embase, and OVID Medline to assess the current landscape of SGA treatment. We searched (“subcutaneous granuloma annulare” OR “pseudorheumatoid nodules” OR “deep granuloma annulare” OR “palisading granuloma”) AND (“treatment” OR “topical” or “injection”). Articles were limited to English language and human subjects. 302 unique studies were screened and assessed for eligibility by two reviewers working independently with disagreements resolved by a third reviewer’s decision. 33 articles met inclusion comprising case reports (n=27), case series (n=3) and retrospective case reviews (n=3) with a total of 149 patients involved. The most predominant treatment was surgical excision/biopsy (n=112) followed by steroid injection (n=6), topical steroid (n=5), and topical antibiotic (n=3). Reports of one patient responding to treatment (n=1) were reported for local hyperthermia, hydroxychloroquine, cyclophosphamide, oral isotretinoin, PUVA light therapy, and pentoxifylline. Of patients studied in these cases, 17 had spontaneous resolution of their lesions either after the treatment window or before starting treatment. One patient was refractory to targeted treatment but had resolution after achieving diabetic control. While surgical excision predominated, biopsy is standard for diagnosis but follow up was not consistent to assess recurrence. Our review calls for more trials and treatment options for SGA.