Review Paper Dermatology Hidradenitis Suppurativa: Disease Burden and Etiology in Skin of Color Dylan E. Lee a Ashley K. Clark b Vivian Y. Shi c a Creighton University School of Medicine, Omaha, NE, USA; b University of California Davis School of Medicine, Sacramento, CA, USA; c Division of Dermatology, Department of Medicine, University of Arizona, Tucson, AZ, USA Received: October 30, 2017 Accepted after revision: January 5, 2018 Published online: March 1, 2018 Vivian Y. Shi, MD Dermatology Division, Department of Medicine University of Arizona, 1515 N. Campbell Ave. PO Box 245024, Building 222, Levy Bldg., 1906E, Tucson, AZ 85724-5024 (USA) E-Mail vshi @email.arizona.edu © 2018 S. Karger AG, Basel E-Mail karger@karger.com www.karger.com/drm DOI: 10.1159/000486741 Keywords Hidradenitis suppurativa · Disease burden · Skin of color Abstract Hidradenitis suppurativa (HS) is a chronic, debilitating skin disease. Although most studies on HS are conducted in largely Caucasian populations, evidence demonstrates a higher prevalence in patients with skin of color, including African and Hispanic populations. These racial subgroups are likely at risk for greater disease burden due to a higher prevalence of components of the metabolic syndrome, co- morbid depression, and low socioeconomic status; however, there is a paucity of research in these populations. Addition- ally, studies examining the genetic and anatomical basis for HS, as well as the response to HS therapies, are lacking for patients with skin of color. Complicating this issue is the lim- ited access to effective medical care, including dermatolo- gists, for African and Hispanic populations as well as other minority groups. In this review, we identify gaps in the knowledge base, highlight the association between HS and patients with skin of color, and provide direction for much needed research into this condition. © 2018 S. Karger AG, Basel Introduction Hidradenitis suppurativa (HS), also known as acne in- versa, is a chronic, inflammatory skin disease that pres- ents with painful and often malodorous abscesses, nod- ules, sinus tracts, and scar formation, usually involving apocrine gland-bearing skin in the axillae, inguinal re- gion, and perianal and perineal regions [1]. The patho- genesis of HS is thought to involve follicular hyperkera- tosis with subsequent occlusion and dilatation of the hair follicle, leading to rupture, inflammation, abscess forma- tion, and, despite possible disease remission, dermal con- tractures and disfiguring scars (Fig. 1) [1]. Risk factors for HS include cigarette smoking, obesity, and metabolic syndrome (MetS) [2, 3]. Although the prevalence of HS varies (from 0.00033 to 4.1%), studies have reported an increased prevalence in African and Hispanic populations, as well as in women [4, 5]. The dis- ease burden of HS is largely due to a profound physical and psychological impact, which leads to depression and impaired quality of life (QoL) [6, 7]. Additionally, there are reports of HS being more common in individuals of low socioeconomic status (SES) [8]. The majority of the published studies on HS include largely Caucasian cohorts [9]. This may not represent the true prevalence of HS with respect to different racial sub- groups, both internationally and in different regions of the USA [10]. More significantly, evidence demonstrates an increased prevalence of HS in individuals with skin of color (SOC); however, there is insufficient research to ad- equately assess the severity, comorbidities, genetic basis, and response to treatment in these populations (Table 1). In this review, we identify these knowledge gaps, under- line the association between HS and minority popula- tions, and provide directions for future research in this