Why Is Rosacea Considered to Be an Inflammatory Disorder?
The Primary Role, Clinical Relevance, and Therapeutic Correlations of Abnormal Innate Immune Response in Rosacea-Prone Skin

June 2012 | Volume 11 | Issue 6 | Original Article | 694 | Copyright © June 2012

which is upregulated and hyper-responsive in facial skin of patients with rosacea as compared to normal skin. Studies in rosacea have demonstrated enhanced receptor recognition through increased expression of TLR-2, and increases in both the AMP cathelicidin and SC serine protease activity (KLK-5), which leads to greater production of pro-inflammatory and vasoactive peptides (ie, LL-37). Clinical manifestations of rosacea correlate with the augmented immune response including erythema associated with diffuse dermal infiltration with lymphocytes (Th1) and macrophages, vascular inflammation with vasodilation and perivascular edema, and in some cases inflammatory lesions related to the chemoattraction of neutrophils with perifollicular inflammation. Other mechanisms associated with rosacea interface with the innate immune response such as MMPs, ROS, and SC permeability barrier function. Ultimately, the major presentations of rosacea appear to be inflammatory dermatoses with a variety of mechanisms contributing to the underlying pathophysiology. Current evidence supports that the presence of a microbial organism is not a primary or mandatory component of the pathogenesis of rosacea. Currently, available therapies for rosacea exhibit modes of action that appear to correlate with the inhibition of inflammatory cascades involved in the pathophysiology of at least some presentations of rosacea. Additional studies are needed to further clarify the pathogenesis of rosacea and modes of action of therapeutic agents used in treatment, including new therapies.


This article is based on an academic rountable discussion completed in New York City in August 2011 chaired by the lead author with participation by all the authors listed on this article. Much of the discussion was based on research presented by Dr. Richard Gallo as well as information from literature review. The paper was mostly written by the lead author with input from the other authors, with administrative support from Educational Awareness Solutions (Norwalk, Connecticut) and without input from any other sources. The participants at the roundtable did receive an honorarium for their attendance and involvement at the roundtable, and in the case of the chairperson, for assisting in review and preparation of a large body of references provided to the participants. None of the authors received honoraria related to writing of the article. The project was supported by an educational grant from Galderma Laboratories provided to Educational Awareness Solutions (Norwalk, Connecticut).
Dr. Del Rosso has served as a consultant, speaker, and/or researcher for Allergan, Bayer (Intendis), Galderma, LeoPharma, Medicis, Nitro- Bio, Obagi Medical Products, Onset Dermatologics, Pharmaderm, Primus, Promius, Ranbaxy, TriaBeauty, Triax, Unilever, Valeant, and Warner-Chilcott.
Dr. Gallo completed research that was funded by the National Institutes of Health and US Veterans Affairs and in the past by the National Rosacea Foundation. He has served as a consultant, and/or researcher for Allergan, Bayer (Intendis), Galderma, Novartis, Johnson and Johnson, Colgate-Palmolive, Sente, and Skin Epibiotics.
Dr. Kircik has served as a speaker, consultant, and/or researcher for Abbott, Acambis, Allergan, Amgen, Assos Pharma, Astellas Pharma, Asubio, Bayer (Intendis), Biogen-Idec, Biolife, Biopelle, Breckinridge Pharma, Colbar, Centocor, Combinatrix, Dusa, Embil, EOS, Ferndale, Galderma, Genentech, GlaxoSmithKline, Innovail, Johnson & Johnson, Laboratory Skin Care, LeoPharma, Medical International Technologies, Medicis, Merz, NanoBio, Novartis, Nucryst Pharmaceutical, Obagi Medical Products, Onset Dermatologics, Promius, PharmaDerm, Quatrix, Serono, SkinMedica, ToleRx, Triax, UCB, Valeant, Warner-Chilcott, and ZAGE.
Dr. Thiboutot has served as a consultant for Galderma and Bayer (Intendis) and as a researcher for Galderma.
Dr. Baldwin has served as a speaker, consultant and/or researcher for Allergan, Galderma, GlaxoSmithKline, Medicis, Onset Dermatologics, Ranbaxy, and Valeant.
Dr. Cohen has served as consultant, for Brickell Biotech, Dermira, Dr. Tattoff, Ferndale, Galderma, Johnson and Johnson, LeoPharma, Onset Dermatologics, Topica, and Vyteris. He serves on the Board of Directors of Brickell Biotech, Topica, and Vyteris. He owns stock or stock options with Brickell Biotech, and Dermira.


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