Perforating granuloma annulare.

With more than 3 years' follow-up, dramatic clinical transfiguration of granuloma annulare was observed in a 59-year-old man with perforating granuloma annulare. The eruption was at first localized, then became generalized, developed perforations, and subsided in parallel with the improvement of associated diabetes mellitus. After reviewing 23 cases of perforating granuloma annulare from the literature, the authors divided the eruptions into two types according to their clinical features, naming one type papular perforating type (P-type) and the other ulcerative perforating type (U-type). U-type is strongly correlated with diabetes; patients with this type require detailed laboratory examination for the presence of diabetes mellitus.