Follicular neutrophilic inflammation (Hidradenitis Suppurativa)

Follicular neutrophilic inflammation or Hidradenitis Suppurativa (HS), also known as acne inversa, is a chronic-relapsing, debilitating inflammatory disease of the hair follicle that usually presents after puberty, affecting apocrine gland-bearing skin, most commonly the axillae, inguinal regions and anogenital area [1]. It is clinically characterized by recurrent, painful, deep-seated nodules commonly ending in abscesses and sinus tracts with suppuration and hypertrophic scarring. Estimates of the prevalence of HS range from less than 0.1% to 4%. Treatment depends on the stage and severity of the disease, ranging from topical and systemic antibiotics for early and benign disease to biologic agents, particularly the tumour necrosis factor (TNF)-α blocker adalimumab for more severe cases; for advanced and recalcitrant lesions, complete removal by surgical excision is regarded as the most effective procedure. Recently, an upregulation of interleukin (IL)-1β and IL-17, which are pivotal cytokines in autoinflammation, has been demonstrated in the lesional skin of patients with both isolated and syndromic HS, suggesting an important autoinflammatory component in the pathogenesis of this disease.