What causes hidradenitis suppurativa?

Abstract

Hidradenitis suppurativa (HS)--a rather common, very chronic and debilitating inflammatory skin appendage disorder with a notoriously underestimated burden of disease--has long been a playground for the high priests of nomenclature: Ask a bunch of eminent dermatologists and skin pathologists to publicly share their thoughts on what causes HS, and they will soon get entrenched in a heated debate on whether this historical term is a despicable misnomer. Fortunately, the recently founded Hidradenitis Suppurativa Foundation (HSF; http://www.hs-foundation.org), to which EXP DERMATOL serves as home journal, has broken with this unproductive tradition and has encouraged publication of the current CONTROVERSIES feature. This is exclusively devoted to discussing the pathobiology of this chronic neutrophilic folliculitis of unknown origin. Although traces of terminological bickering remain visible, it does the HS experts in our virtual debate room credit that they engage in a constructive and comprehensive dissection of potential pathogenesis pathways that may culminate in the clinical picture we know under the competing terms HS or acne inversa. These experts sketch more often complementary than mutually exclusive pathogenesis scenarios, and the outlines of a conceivable consensus on the many open pathobiology questions begin to emerge in these CONTROVERSIES. Hopefully, this heralds a welcome new tradition: to get to the molecular heart of HS pathogenesis, which can only be achieved by a renaissance of solid basic HS research, as the key to developing more effective HS therapy.

A cross‐sectional epidemiological study of hidradenitis suppurativa in an Irish population (SHIP)

“…The disease is characterized by painful, inflammatory nodules or boils that may progress to abscesses, sinus tract formation and scarring 2, 3. Although the aetiology of HS is largely unknown, it is likely that multiple factors contribute to the development of the disease 4…”

The Effect of Combined Treatment with Oral Clindamycin and Oral Rifampicin in Patients with Hidradenitis Suppurativa

“…It has a significant impact on the patients’ quality of life [2, 3]. The exact cause of HS remains unclear [4]. Histopathological studies have suggested occlusion of the follicular infundibulum as an important factor [5, 6].…”

“…HS is currently thought of as being a sterile inflammation, but bacteria are suspected of playing a role in the disease process, although not that of a simple infection. It is speculated that bacteria may play a part through immune-mediated mechanisms of inflammation in association with a dysregulated immune response in the hair follicles [4]. Antibiotic therapy is however widely used and mentioned in all textbooks of dermatology as a prominent form of treatment for HS.…”

Hidradenitis Suppurativa Complicating Naevus Comedonicus: The Possible Influence of Mechanical Stress on the Development of Hidradenitis Suppurativa

“…It is rare in children. While its aetiology remains unknown, the organs involved and the pathogenesis of the disease are thought to be well understood [2]. Several studies have identified the hair follicle as the core element of hidradenitis, prompting some authors to suggest that the disease be renamed acne inversa, although substantial differences exist between the 2 diseases [1,3,4,5,6].…”