Clinical and pathological features of generalized granuloma annulare with their correlation: a retrospective multicenter study in Korea

Generalized granuloma annulare (GGA) is a benign skin disorder of an unknown etiology. Though some cases of GGA have been reported, few systemic reviews of the clinical and pathological features of GGA have been performed. The purpose of this study is to analyze and correlate the clinical and pathological characteristics of GGA in Korean patients. We conducted a retrospective study that included 54 biopsy specimens of Korean GGA patients, and the clinical and pathological features of GGA were reviewed and analyzed for their correlation. The cutaneous lesions could be divided into the annular (24, 44%) and nonannular types (30, 56%), and the lesions were more common in males than in females (29 males and 25 females). The incidence of GGA showed a bimodal age distribution. The number of patients who presented within the first decade was 24 cases (44%), and 24 cases (44%) were over the fifth decade. Eight patients (15%) had systemic diseases. Especially, diabetes mellitus (DM) occurred only in the adult GGA patients over forty years old. The pathological findings showed dermal granulomatous lesions that consisted of either a palisading pattern (28, 52%) or an interstitial pattern (26, 48%). In contrast to the previously reported studies, the age of GGA onset showed a bimodal distribution, and GGA was observed more often in males. The prevalence of DM in the GGA affected individuals was higher than that found in the general Korean population. Therefore, it is recommended to perform a work-up for DM in the GGA affected patients who are over forty years old.