Quantitative histopathologic findings of erythromelanosis follicularis faciei et colli

Background: Even though only 33 cases of Erythromelanosis follicularis faci ei et colli (EFFC) hare been reported around the world, there have been no quantitative clinicopathological studies yet. The purpose of this study is to examine quantitatively clinical and histopathological evaluations of EFF C using image analysis system. Method: Clinical grading of its severity was assessed. Many parameters of t he horny layer, granular layer, epidermis and the dermal components were me asured and compared to controls by image analysis. The correlation between the histological findings and clinical grading was assessed. Result: Thickness and compactness of the horny layer was significantly incr eased in EFFC. There were no significant differences in the number of melan ocytes and severity of pigmentation between EFFC and controls; however, mel anization was slightly increased in EFFC. The percent area of the superfici al blood vessels was significantly increased and correlated with visual gra ding of erythema. Diameters of hair shafts and outer root sheaths, and thic kness of inner root sheaths were decreased. Basal layer pigmentation was co rrelated with the clinical features of pigmentation. Conclusion: This study supported the findings of hyperkeratosis and dilatat ion of superficial dermal blood vessels in EFFC. The pigmentation of the ba sal layer and the percent area of the inner spaces of the superficial derma l blood vessels may reflect the clinical severity more than the other param eters. Although follicular plugging is a characteristic clinical feature of EFFC, enlargement of hair follicles and hair shafts were not characteristi c pathologic changes EFFC in our study.