RT Book, Section A1 Haggstrom, Anita N. A2 Rudolph, Colin D. A2 Rudolph, Abraham M. A2 Lister, George E. A2 First, Lewis R. A2 Gershon, Anne A. SR Print(0) ID 7032803 T1 Chapter 359. Disorders of the Dermis and Subcutaneous Tissue T2 Rudolph's Pediatrics, 22e YR 2011 FD 2011 PB The McGraw-Hill Companies PP New York, NY SN 978-0-07-149723-7 LK accesspediatrics.mhmedical.com/content.aspx?aid=7032803 RD 2024/11/04 AB Granuloma annulare is a common benign inflammatory disorder of uncertain pathogenesis that is classically characterized by asymptomatic, flesh-colored to pink or violaceous, nonscaly annular plaques typically located over the dorsa of the hands and feet. (Fig. 359-1) Less common variants include generalized, perforating, and subcutaneous granuloma annulare. The lesions of classic granuloma annulare are round to oval and are often misdiagnosed as tinea corporis (eFig. 359.1). However, unlike tinea infections, the lesions have a smooth, sometimes firm border that lack epidermal scale. Lesions of subcutaneous granuloma annulare appear as asymptomatic to slightly tender, flesh-colored nodules that can occur anywhere, although they are often on the lower legs and scalp. Atypical locations, including the palmar surfaces and eyelids, have reported (eFig. 359.2).1 The differential diagnosis of granuloma annulare includes tinea corporis, necrobiosis lipoidica, rheumatoid nodules, and cutaneous sarcoidosis. Adults who develop this disorder may be more likely to have diabetes, but this association is not seen in children. Histologically, granuloma annulare displays altered collagen and mucin surrounded by distinctive “palisade” of histiocytes. There are also interstitial variants where the collagen alteration is less obvious. In subcutaneous granuloma annulare, the inflammatory process primarily involves the fat. Treatment is generally unsatisfactory. Topical steroids or intralesional steroids can limit progression, but results are not dramatic. Systemic steroids, isotretinoin, hydroxychloroquine, dapsone, and ultraviolet light therapy have been attempted in patients with disseminated granuloma annulare with limited success. Fortunately, granuloma annulare is an indolent process that eventually stabilizes and resolves without scarring over several years.