Epidermal inflammatory activity is an important driver of hidradenitis suppurativa lesions

Hidradenitis suppurativa (HS) is an inflammatory skin disorder of the pilosebaceous unit defined by painful nodules, tunnels, and scarring. Previous studies documented dermal cell infiltrate and the abundance of inflammatory cytokines in HS lesions, including TNFα, IL-17, and IL-1β. However, not much is currently known about the contribution of keratinocytes and immune cell activity within the epidermis in HS. We found that the degree of epidermal inflammation in HS lesions positively correlated with Hurley stage of disease (r =0.746; p=0), indicating the evolution of epidermal responses with disease severity.