Crystal Deposition in Hidradenitis Suppurativa

Histopathology of Hidradenitis Suppurativa: A Systematic Review

“…We found that follicular occlusion (Figure 2a), follicular hyperkeratosis, hyperplasia of follicular epithelium, epidermal psoriasiform hyperplasia, and perifolliculitis were among the most common reported histopathologic features [8,17,21,24]. phils, although few [13,17]. These findings were not consistent with previous studies, which did not report eosinophils in excision specimens.…”

“…Based on the review, 253 were excluded because they did not meet the inclusion criteria. After a thorough review of these remaining articles, 61 studies failed to meet the inclusion criteria or were found to be duplicates, resulting in a total of 15 articles for analysis and 3 additional articles were hand-searched ( Figure 1 ) [ 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ]. Of the 18 studies included in this review, all quantified and described the histopathology of HS.…”

“…One recent study that examined HS histopathologic changes reported eosinophils in 10 of 16 lesional specimens examined [ 19 ]. Two additional studies also reported eosinophils, although few [ 13 , 17 ]. These findings were not consistent with previous studies, which did not report eosinophils in excision specimens.…”

“…Follicular occlusion is expected to be directly proportional to perifolliculitis in this circuit, and our review showed they were directly proportional, supporting the important relationship between follicular occlusion and perifolliculitis [ 8 ]. Other findings in the epidermis and dermis include acute and chronic inflammation, plasmocytic infiltrate ( Figure 2 b), abscess, tunnels, cyst, fibrosis, pseudoeptheliomatous hyperplasia (PEH), and epidermal psoriasiform hyperplasia (EPH), which are not uncommonly seen ( Figure 3 and Figure 4 ) [ 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ].…”