Localization of TNF-α13, IL-1232, IL-2332 and IL-324, TLR240, MMP213, MMP843 and LL-37/cathelicidin14,29 production to infiltrating dermal macrophages and lymphocytes as well as localization of IL-36 subtypes5, LL-37/cathelicidin14,29, IL-1β32 and IL-2232 to keratinocytes illustrate the feed forward mechanisms similar to those seen in psoriasis9 and atopic dermatitis10 which likely contribute to persistent inflammation in HS. This evidence concerns the gene CAMP and histiocytic sarcoma.