SKIN March 2019 Volume 3 Issue 2 Copyright 2018 The National Society for Cutaneous Medicine 141 RISING DERM STARS® Characterizing the Alopecia Areata Microbiome Margit Juhász, MD, MSc1, Natasha Atanaskova Mesinkovska, MD, PhD 1University of California, Irvine, Department of Dermatology, Irvine, CA Background: Alopecia areata (AA) is an inflammatory, non-scarring hair loss resulting from autoimmune attack of the hair follicle, affecting as much as 2% of the population. Researchers have not determined the exact pathogenesis of AA, but hypotheses include imbalances in innate immunity, environmental insults, and genetic predisposition. The microbiome is a community of commensal and pathogenic microorganisms that live on and within our bodies. With growing evidence that the microbiome plays a significant role in inflammatory skin conditions such as atopic dermatitis and psoriasis, recent cases postulate that the gut microbiome plays a role in AA development. Methods: In this pilot study, we aim to characterize the local (scalp) and global (gut) microbiome of AA patients and determine if there are significant differences when compared to healthy controls. Microbiome samples were collected from 25 subjects with AA and 25 healthy controls living in Southern California at a single, academic medical center; controls were age, gender and race- matched to alopecia patients. At the time of sample collection, all subjects were required to have no active gastrointestinal disease. Scalp swabs and stool samples were obtained from each subject. After DNA was isolated from each sample, 16s RNA and internal transcribed spacer (ITS) libraries were created to identify bacterial and fungal taxonomy, respectively. Multi-variant analysis comparing the alopecia to control microbiomes was performed. Results: AA subjects were 40.3 ± 14.7 years old, female (72%) and identified as Caucasian (60%). There were no significant differences noted in the demographic make- up of the alopecia and control groups. Significant differences were noted in both the scalp and gut microbiome of alopecia patients compared to controls. Alopecia patients’ scalp samples had significantly decreased Firmicutes (p<0.05) and increased Actinobacteria trending to significance, while their gut microbiome was significant for decreased Bacteroides (p<0.05) and increased Firmicutes trending to significance. Conclusion: Microbiome dysbiosis may cause inappropriate systemic immune response and inflammation leading to autoimmune alopecia in predisposed patients. It is our hope that this preliminary data may be used in the future to characterize changes in the scalp and gut microbiome that may be related to AA disease severity, patient dietary practices, and even predict prognosis and/or therapeutic response. SKIN March 2019 Volume 3 Issue 2 Copyright 2018 The National Society for Cutaneous Medicine 142 References: 1. Adams, RL, Miletto, M, Taylor, JW, Bruns, TD. The diversity and distribution of fungi on residential surfaces. Plos One. 8:e78866, 2013. 2. Findley, K, Oh, J, Yang, J, Conlan, S, et al. Topographic diversity of fungal and bacterial communities in human skin. Nature. 498:367-70, 2013. 3. Hayashi, A, Mikami, Y, Miyamoto, K, Kamada, N, et al. Intestinal dysbiosis and biotin deprivation induce alopecia through overgrowth of Lactobacillus murinis in mice. 20(7):1513-24, 2017. 4. Rebello, D, Wang, E, Yen, E, Lio, P, Kelly, C. Hair growth in two alopecia patients after fecal microbiota transplant. ACG Case Reports Journal. 4(e107):doi:10.14309/crj.2017.107, 2017. 5. Sinha, R, Chen, J, Amir, A, Vogtmann, E, et al. Collecting fecal samples for microbiome analyses in epidemiology studies. Cancer Epidemiol Biomarkers Prev. 25(2):407-16, 2016. SKIN March 2019 Volume 3 Issue 2 Copyright 2018 The National Society for Cutaneous Medicine 143 Figure 1: Comparison of the scalp bacterial microbiome from alopecia patients to healthy controls reveals significantly decreased Firmicutes (p=0.00063) in alopecia samples.