# Internal Medicine/Acne
## Acne Vulgaris

Acne vulgaris is a common, self-limiting skin condition primarily affecting teenagers and young adults, with a small percentage of adults continuing to experience it. The key trigger for acne during adolescence is the increased production of sebum (skin oil) by sebaceous glands due to puberty. This excess oil, combined with the retention of keratin and sebum in hair follicles, leads to the formation of small cysts called comedones. Bacteria, particularly Cutibacterium acnes, present in these comedones, release free fatty acids, causing inflammation within the cysts and leading to their rupture. As a result, an inflammatory response occurs due to the extrusion of oily and keratinous material from the cysts.
The primary feature of acne vulgaris is the comedone, which can be either closed (whiteheads) or open (blackheads). Closed comedones appear as small, raised white papules, while open comedones have a dilated follicular opening and contain darkened, easily expressible, oxidized debris. Comedones are often accompanied by inflammatory lesions such as papules, pustules, or nodules. Acne initially appears as mildly inflamed or noninflammatory comedones on the forehead in adolescence. Later, more typical inflammatory lesions develop on the cheeks, nose, and chin. The face is the most common site for acne, but it can also affect the chest and back. Most cases are mild and do not lead to scarring, but severe forms can result in significant and sometimes permanent scarring. Acne can have a significant impact on a person's quality of life, and early treatment is essential for severe cases.
Various external and internal factors can influence the development of acne, including friction or trauma, use of comedogenic cosmetics or hair products, topical exposure to certain industrial compounds, and certain medications. Genetic factors and conditions like polycystic ovary disease may also contribute to acne.
The treatment of acne vulgaris aims to eliminate comedones by normalizing follicular keratinization, reducing sebaceous gland activity, controlling Cutibacterium acnes population, and managing inflammation. Minimal to moderately inflamed acne can often be managed with topical therapy. It's important to keep the affected areas clean, but excessive scrubbing can worsen acne. Topical agents like retinoic acid, benzoyl peroxide, or salicylic acid can help prevent comedone formation and resolve existing cysts. Topical antibacterial agents (e.g., benzoyl peroxide, azelaic acid, erythromycin, clindamycin, or dapsone) can be used in combination with other treatments to prevent bacterial resistance.
Patients with moderate to severe acne and significant inflammation may benefit from oral antibiotics such as minocycline or doxycycline. These antibiotics have anti-inflammatory effects apart from their antibacterial properties. Female patients who don't respond to antibiotics might find hormonal therapy, including oral contraceptives, effective. Spironolactone is also emerging as a safe and durable antiandrogen treatment for women with acne.
In cases of severe, nodulocystic acne unresponsive to other treatments, isotretinoin, a synthetic retinoid, can be considered. It's administered based on body weight and cumulative dosage, with treatment duration determined by lesion remission. Isotretinoin has excellent results but is associated with potential severe side effects, including teratogenicity and depression. Its use is highly regulated to minimize these risks, including mandatory enrollment in a program to prevent pregnancy and monitor potential side effects.

## Acne Rosacea

Acne rosacea, commonly known as rosacea, is an inflammatory skin condition primarily affecting the central face. It's most commonly observed in Caucasians of northern European descent but can also affect individuals with darker skin tones. Unlike acne vulgaris, rosacea typically occurs in adults and rarely affects those under 30. It's more prevalent in women, but men often experience more severe forms. Rosacea is characterized by facial redness, visible blood vessels (telangiectasias), and superficial pustules. Unlike acne vulgaris, rosacea does not involve comedones. The condition can lead to connective tissue overgrowth, particularly on the nose (rhinophyma), and can also affect the eyes, potentially causing various inflammatory eye disorders.
Rosacea can be treated through topical or systemic approaches. Mild cases often respond well to topical treatments like metronidazole, sodium sulfacetamide, azelaic acid, ivermectin, brimonidine, or oxymetazoline. More severe cases may require oral tetracyclines in subantimicrobial doses or modified-release preparations. Laser therapy can be effective for treating residual telangiectasia. It's important to avoid using potent topical steroids as chronic use can exacerbate rosacea. Topical treatments are ineffective for ocular involvement, and such cases require specialized treatment from an eye specialist.