From the Guidelines
Acne is primarily caused by a multifactorial pathogenesis involving follicular hyperkeratinization, microbial colonization with Cutibacterium acnes, sebum production, complex inflammatory mechanisms, and genetic and nongenetic factors. The development of acne is influenced by various factors, including:
- Increasing age during adolescence
- Family history of acne
- Oily skin type
- Hormonal changes, particularly during puberty, pregnancy, or with certain medical conditions, which stimulate increased oil production 1
- Genetics, which play a significant role in determining susceptibility to acne
- Certain medications, such as corticosteroids, androgens, and lithium
- Diet, with high-glycemic foods and dairy potentially worsening acne in some individuals
- Stress, which can increase hormone production
- Improper skincare routines
The bacteria Cutibacterium acnes naturally lives on the skin but multiplies rapidly in clogged pores, triggering inflammation 1. The combination of excess oil production, clogged hair follicles, bacteria, and inflammation ultimately leads to the development of acne. Regular gentle cleansing, avoiding pore-clogging products, and treatments containing ingredients like benzoyl peroxide, salicylic acid, or retinoids can help manage acne by addressing these underlying causes 1.
From the Research
Causes of Acne
- Acne is a chronic inflammatory disease of the pilosebaceous unit resulting from androgen-induced increased sebum production, altered keratinisation, inflammation, and bacterial colonisation of hair follicles on the face, neck, chest, and back by Propionibacterium acnes 2
- The pathogenesis involves altered follicular growth and differentiation, microbial colonization with Cutibacterium acnes, increased sebum production influenced by androgen levels, and inflammation 3
- Other factors such as diet have been implicated, but not proven 2
- Family history and body mass index are evidence-based risk factors for acne 3
Triggers of Acne
- Early colonisation with P acnes and family history might have important roles in the disease, but exactly what triggers acne remains unclear 2
- Androgen-induced increased sebum production is a key factor in the development of acne 2, 3
- Inflammation and bacterial colonisation of hair follicles also play a role in the development of acne 2, 3
Types of Acne
- Acne can be classified based on patient age, lesion morphology (comedonal, inflammatory, mixed, nodulocystic), distribution (location on face, trunk, or both), and severity (extent, presence or absence of scarring, postinflammatory erythema, or hyperpigmentation) 4
- Acne can be mild, moderate, or severe, and can persist into adulthood with detrimental effects on self-esteem 2, 4