To cite this article: Dermoscopy in general dermatology (non-neoplastic dermatoses) of skin of colour: a comparative retrospective study by the International Dermoscopy Society.

Introduction: Frontal fibrosing alopecia (FFA) is a form of primary lymphocytic scarring alopecia characterized by a progressive recession of the fronto-temporal hairline. Although the clinical presentation of FFA is very typical, biopsy for histopathological examina­tion is still recommended to confirm the diagnosis. Currently, a growing number of skin and mucosal inflammatory diseases are diagnosed with modern noninvasive techniques such as dermoscopy without the necessity of a biopsy. Objectives: The International Dermoscopy Society (IDS) aimed to test the ability of its members to diagnose classic FFA through clinical and dermoscopic parameters and to compare acquired data to the largest cohort studies published since 1994. Methods: This is an observational, cross-sectional study describing patient demographics, clinical presentation and diagnostic tools used in a sample of FFA patients collected by IDS members. A literature search was then performed using Pubmed to review studies reporting more than 100 cases. Results: IDS members submitted 188 cases demonstrating a predominant female population (98.4%). In 71.8% of the cases, the clinical presentation and the trichoscopic findings allowed for the diagnosis. Out of 24 revised studies, 13 showed that clinical and trichoscopic features were decisive for the diagnosis in almost all cases. Conclusions: Demographic and clinical data of our cohort were mostly comparable to previous reported data on FFA. The relevant role of the clinical and trichoscopic features in diagnosing FFA was confirmed by our study and the reviewed literature. Trichoscopy could be considered a worldwide-acknowledged non-invasive technique for the diagnosis of FFA.

Background The International Dermoscopy Society (IDS) recently released a set of five basic dermoscopic parameters (vessels, scales, follicular findings, "other structures," and specific clues) encompassing a total of 31 subitems to standardize the use of dermoscopy in non-neoplastic dermatoses, yet they have been developed taking into account Caucasian/Asian skin, with consequent possible limitations if used in dark skin. Objectives To validate the abovementioned criteria for the use in dark-skinned patients (phototypes IV-VI) through an expert consensus. MethodsThe two-round Delphi method was adopted, with an iterative process consisting of two rounds of email questionnaires. Potential panelists were recruited via e-mail from all over the world based on their expertise on dermoscopy of non-neoplastic dermatoses in skin of color.Results Twenty-two panelists took part in the validation process. All of the five originally proposed parameters and subitems reached agreement during the first round, aside from "follicular red dots." Additionally, during round 1, five new subitems were proposed (perifollicular scales distribution, follicular openings obliteration, broken hairs, eccrine pigmentation, and eccrine ostia obliteration), along with the possibility to change the denomination of parameter 3 (from "follicular findings" to "follicular/eccrine findings") and split it into two subparameters ("follicular findings" and "eccrine findings"). All such proposals reached agreement during the second round and therefore were included in the final list, for a total of 37 items.Conclusions Although nearly all the dermoscopic criteria originally proposed by the IDS are applicable even to darker phototypes, several additional variables need to be assessed.