Abstract
The pathophysiology of hidradenitis suppurativa (HS) is not well understood. Some of our knowledge comes from clinical and epidemiological observations, along with studies of the histopathology and immunohistochemistry of affected skin. More recently, cutaneous molecular studies and transcriptomic analyses have provided additional information regarding inflammatory processes. The chronic cutaneous inflammation, systemic symptoms, and associated comorbidities suggest that HS should be classified as an immune-mediated disease, rather than a primary infectious disease. As such, a proposed integrated disease pathway is presented. At a fundamental level, there appears to be a primary abnormality in the pilosebaceous-apocrine unit, which leads to follicular occlusion, perifollicular cyst development that traps commensal microbes, and rupture into the dermis. This can trigger an exaggerated response of the cutaneous innate immune system. Initially this is an acute event, but ongoing intermittent disease activity can lead to recurrent inflammatory nodules and dermal tunnels. Once underway, the cutaneous inflammation is very difficult to turn off, leading to suppurative inflammation in whole anatomic regions. As the disease progresses, we propose that there is recruitment of the systemic immune system perpetuating the chronic cutaneous inflammatory process. There remains much to be done to understand the pathogenesis and immune signature of this challenging disease
Conclusion
As we are in the early stages of defining the pathophysiology of HS using modern molecular approaches, this review has focused on clinical observations and studies on lesional skin and the immune system to synthesize what they reveal about the causes of HS. It is clear that HS is a complicated disease, which results in great morbidity and impairment of quality of life. We do not yet have a complete understanding of the pathophysiology, and it is essential that we address this unmet need urgently. As we go forward, we can leverage our knowledge about other chronic immune-mediated diseases to guide future studies to help our suffering patients.
Full Research:
https://pubmed.ncbi.nlm.nih.gov/28538743/?from_term=Hidradenitis+innate+immune&from_pos=10