SEARCH RESULTS FOR: Hidradenitis-Suppurativa

Hidradenitis Suppurativa

Genetic mutations causing impaired function of gamma-secretase (NCSTN, PSEN1 or PSENEN genes) Defective notch signaling pathway (a regulator of many cell processes) Hormones (excess androgen activity) Smoking (nicotine exposure) Skin to skin friction Systemic inflammation Hidradenitis Suppurativa: Pathogenesis and Clinical Findings Other unknown genetic factors Follicular occlusion HS nodule Epidermal layer Dermal- Epidermal Junction Dermal layer Inflammatory cytokine- mediated activation of nociceptors Inflammatory cytokines Sebaceous gland Apocrine sweat gland Hair follicle Pilosebaceous- apocrine unit Changes in gene expression of hair follicle and apocrine gland anti-microbial peptides Accumulation of corneocytes (dead keratinocytes) and sebum àfollicular occlusion and rupture ↑ Interleukin-36 (IL-36, a cytokine) Altered keratinocyte differentiation Hair follicle hyperkeratinization Abnormal structure and function of the pilosebaceous- apocrine unit Infiltration of normal skin flora microbes, macrophages, dendritic cells, and Th17 cells Increased density of nicotinic acetylcholine receptors in pilosebaceous-apocrine unit (see figure) Mechanism not fully understood Hyperhidrosis Pain Innate immune cells produce inflammatory cytokines: tumour necrosis factor alpha (TNF-α) and various interleukins (IL-1, IL-6, IL-12, IL-17, IL-22 and IL-23) IL-17 promotes neutrophil migration into the skin Formation of neutrophil extracellular traps (NETs) B-cell activation and IgG autoantibody formation against skin tissue antigens Scarring Ongoing inflammation impairs wound healing Granulocyte infiltration and activation, release of granulocyte colony-stimulating factor Accumulation of keratin, purulent and/or serosanguinous fluid in dermis Inflammatory papules, nodules, and abscesses Pro-inflammatory cytokine-mediated response, leading to epithelial hyperplasia with increased fibrosis and collagen remodelling in the dermis Formation of epithelial tissue tunnels in the dermis with two cavities on either end that open to the skin surface and fill with fluid or keratin Hidradenitis Suppurativa Chronic Inflammatory skin disease that occurs in areas with a high density of apocrine sweat glands, including the axilla, underneath the breasts, groin, and buttocks Sinus tracts (dermal connections between lesions) Double-ended comedones Authors: Leah Johnston Reviewers: Mehul Gupta Lauren Lee Stephen Williams Ben Campbell Laurie Parsons* * MD at time of publication Wound drainage and odour Psychological distress Legend: Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications Published January 30, 2023 on www.thecalgaryguide.com