Acne

Understanding Acne: A Complex Skin Condition

Acne (AK-nee) is a long-term skin condition caused by dead skin cells and oil clogging hair follicles, leading to blackheads, whiteheads, pimples, oily skin, and possible scarring. It primarily affects areas with high oil glands, such as the face, chest, and back.

Imagine your skin as a bustling city where tiny factories (hair follicles) produce an essential resource (sebum). In some cities, these factories become overactive, producing too much sebum, which can lead to blockages. When dead skin cells join the party, they get stuck in these clogged pathways, forming comedones—those pesky blackheads and whiteheads that make your face look like a construction site.

Now, let’s dive into the factors that contribute to this complex condition. Genetics play a significant role; 80% of cases are hereditary. Hormones like androgens, bacteria such as Cutibacterium acnes, and diet may also be involved in triggering or exacerbating acne.

Acne affects approximately 633 million people globally, commonly occurring in adolescence, and persists in nearly half of affected individuals into their twenties and thirties. Severity can be classified as mild, moderate, or severe, depending on the presence of clogged skin follicles and inflammatory lesions. The term nodulocystic has been used in medical literature to describe severe cases of inflammatory acne, now known as severe nodular acne.

Acne inversa and acne rosacea are not forms of acne but rather skin conditions that resemble it. Hidradenitis suppurativa (HS) is a skin disorder that shares some features with acne vulgaris but lacks its hallmark features.

Signs, Symptoms, and Scarring

The signs and symptoms of acne include increased sebum secretion, microcomedones, comedones, papules, nodules, pustules, and often scarring. Scars are caused by inflammation within the dermis and can affect 95% of people with acne vulgaris.

Acne scars are classified into atrophic (lost collagen) and hypertrophic (increased collagen content). Boxcar, ice-pick, and rolling scars are subtypes of atrophic acne scars. Hypertrophic scars remain within the original margins of the wound, while keloid scars can form scar tissue outside these borders.

Pigmentation changes after an inflamed nodular acne lesion resolve, leading to postinflammatory hyperpigmentation (PIH). PIH occurs more frequently in people with darker skin color and can be prevented or fade with time. Risk factors for acne include genetics, hormones, infections, diet, and stress.

Acne appears to be highly heritable, with 81% of the variation in the population attributed to genetic factors. Hormonal activity, particularly during puberty and menstrual cycles, can contribute to acne. Infections with anaerobic bacteria Cutibacterium acnes and parasitic mites Demodex have been linked to the development of acne. Diet, particularly high-glycemic-load diets, may also play a role in the severity of acne.

Observational evidence suggests dairy milk consumption is positively associated with higher frequency and severity of acne due to components such as whey protein and hormones like bovine IGF-1, which promote insulin and androgen hormone production. Vitamin B12 may trigger skin outbreaks similar to acne when taken in excess doses.

There are few high-quality studies demonstrating stress causes or worsens acne, but some research suggests increased severity is associated with high-stress levels in certain contexts. Some individuals experience severe intensification of acne in hot humid climates, known as tropical acne.

Treatment and Management

Mechanical obstruction, certain medications, genetically susceptible individuals, and polymorphous light eruption can also cause acne or exacerbate existing conditions. Acne vulgaris is a chronic skin disease caused by blockages in the pilosebaceous unit due to factors such as increased oily sebum production, keratin deposition, C. acnes bacteria colonization, and pro-inflammatory chemical release.

The earliest pathologic change is the formation of a microcomedone driven by excessive growth and accumulation of skin cells in the hair follicle. In healthy skin, dead skin cells exit pores but in people with acne, oily sebum blocks pores, forming microcomedones that can become blackheads or whiteheads.

Hormonal drivers like dihydrotestosterone and DHEA-S stimulate sebaceous gland activity. The bacterium C. acnes grows in a sebum-rich environment, triggering inflammation by activating immune system receptors and altering fatty composition of oily sebum, leading to increased IL-1α levels and recruitment of inflammatory T cells.

Acne vulgaris is caused by a combination of factors including: – Conversion of sebum triglycerides to pro-inflammatory free fatty acids via lipase enzyme secretion. – Increased production of cathelicidin, HBD1, and HBD2 leading to further inflammation. – Inflammatory cascade leading to formation of acne lesions.

Bacteria C. acnes and Staphylococcus epidermidis play a role in the physiopathology of acne vulgaris. Acne vulgaris is diagnosed based on clinical judgment, medical history, and physical examination. Diagnosis criteria include presence of comedones (blackheads and whiteheads), hormonal influences, and other features such as onset between ages 20-30 and inflammatory/nodular acne lesions.

Several scales exist to grade the severity of acne vulgaris, including Cook’s scale, Leeds acne grading technique, and Pillsbury acne grading scale. Such conditions include angiofibromas, epidermal cysts, flat warts, folliculitis, keratosis pilaris, milia, perioral dermatitis, and rosacea, among others.

Age is one factor that may help distinguish between these disorders. Skin disorders such as perioral dermatitis and keratosis pilaris can appear similar to acne but tend to occur more frequently in childhood. Rosacea tends to occur more frequently in older adults. Facial redness triggered by heat or the consumption of alcohol or spicy food is also more suggestive of rosacea.

The presence of comedones helps health professionals differentiate acne from skin disorders that are similar in appearance. Chloracne and occupational acne due to exposure to certain chemicals & industrial compounds, may look very similar to acne vulgaris.

Treatment Options

Many different treatments exist for acne. These include alpha hydroxy acid, anti-androgen medications, antibiotics, antiseborrheic medications, azelaic acid, benzoyl peroxide, hormonal treatments, keratolytic soaps, nicotinamide (niacinamide), retinoids, and salicylic acid.

Acne treatments work in at least four different ways. Typical treatments include topical therapies such as antibiotics, benzoyl peroxide, and retinoids, and systemic therapies, including antibiotics, hormonal agents, and oral retinoids.

Recommended therapies for first-line use in acne vulgaris treatment include topical retinoids, benzoyl peroxide, and topical or oral antibiotics. Procedures such as light therapy and laser therapy are not first-line treatments.

People often view acne as a short-term condition, some expecting it to disappear after puberty. This misconception can lead to depending on self-management or problems with long-term adherence to treatment.

In general, people with acne should not wash affected skin more than twice daily. Fragrance-free moisturizers may reduce irritation. Non-comedogenic and oil-free cosmetic products are recommended for patients with acne.

Moisturizing is essential for acne-prone skin to support the skin’s moisture barrier. Ceramide-containing moisturizers are particularly helpful, as they enhance acne therapy adherence and complement existing acne therapies. The importance of preserving the acidic mantle is widely accepted for maintaining healthy skin conditions.

Conclusion

The battle against acne is a multifaceted one, involving genetics, hormones, bacteria, diet, and stress. Understanding these factors can help in managing this common yet complex condition. By recognizing the signs, seeking appropriate treatment, and adopting a holistic approach to skincare, you can take steps towards clearer skin.