From the Guidelines
Hidradenitis suppurativa is a chronic inflammatory skin condition primarily caused by blockage of hair follicles in areas with apocrine sweat glands, such as the armpits, groin, buttocks, and under the breasts, with the exact cause remaining unclear but several factors contributing to its development, as supported by the most recent study 1. The condition is characterized by painful, recurrent nodules and abscesses that rupture and lead to the formation of sinus tracts and scarring, having a psychologically meaningful and clinically significant negative effect on the patient’s quality of life 1. Key factors that contribute to the development of hidradenitis suppurativa include:
- Genetic predisposition, with about one-third of patients having a family history of the condition
- Hormonal factors, as the condition often begins after puberty and can worsen during menstruation or pregnancy in women
- Obesity, creating more skin friction and increasing inflammation
- Smoking tobacco, which strongly correlates with hidradenitis suppurativa development and severity
- An abnormal immune response, driving the inflammation, with the body overreacting to normal bacteria on the skin
- Bacterial infection, which is not the primary cause but can complicate existing lesions
- Certain medications like lithium and hormonal contraceptives, which may trigger flares in some individuals
- Environmental factors such as heat, humidity, and tight clothing, which can exacerbate symptoms by increasing friction and sweat production in affected areas
- Stress, which may worsen symptoms through its effects on the immune system and inflammation, as suggested by the epidemiology of hidradenitis suppurativa and its comorbid conditions 1. It is essential to consider these factors when managing hidradenitis suppurativa, as they can impact the effectiveness of treatment and the patient's quality of life.
From the Research
Causes of Hidradenitis Suppurativa
The causes of hidradenitis suppurativa (HS) are complex and multifaceted, involving various factors. Some of the key factors associated with the development of HS include:
- Genetic factors: Studies have identified several genetic variants associated with HS, including those involved in gamma-secretase subunits, autoinflammatory genes, and keratinization genes 2, 3.
- Hormonal factors: Hormonal changes, particularly androgen signaling, have been linked to the development of HS 3.
- Lifestyle factors: Lifestyle factors such as obesity and smoking have been associated with an increased risk of developing HS 4, 5.
- Immunologic factors: Immunologic derangements, including innate and adaptive immunity, have been implicated in the pathogenesis of HS 6, 3.
- Environmental factors: Environmental factors, such as the cutaneous and gut microbiomes, may also play a role in the development of HS, although the exact relationship is unclear 3.
- Metabolic factors: Metabolic syndrome, insulin resistance, and adipose tissue have been linked to the development of HS, particularly in relation to hormonal changes 3.
Pathogenesis of Hidradenitis Suppurativa
The pathogenesis of HS is complex and involves the interplay of multiple factors, including:
- Inflammatory dysregulation: Chronic inflammation is a hallmark of HS, leading to irreversible skin damage and scarring 6.
- Stem cell fate aberrations: Aberrations in hair follicle stem cell fate have been linked to the development of HS 3.
- Activation of inflammatory fibroblast subsets: Activation of inflammatory fibroblast subsets has been implicated in the pathogenesis of HS 3.
- Tertiary lymphoid organs: Tertiary lymphoid organs have been observed in chronic HS, suggesting a role for adaptive immunity in the disease 3.