Hidradenitis suppurativa lesions are associated with decreased collagen, decreased elastin, and increased neovascularization.

Hidradenitis suppurativa (HS) is a dermatological condition characterized by ruptured hair follicles inducing a localized, but massive chronic inflammatory response. Analysis of 104 HS lesions in formalin-fixed paraffin-embedded tissues identified the most common histologic features found associated with HS were migrating epithelial sheets, acute and chronic inflammation, perivascular chronic inflammation in regions adjacent to active lesions, and granulation tissue. Additionally, using a modified Masson's trichrome stain principally for collagen, Verhoeff van Gieson elastic stain, and CD34 immunohistochemistry assay for endothelium, lesional areas in the dermis with chronic inflammation exhibited a significant decrease in collagen and elastin, and an increase in neovascularization.