Acne

Definition

Acne is a chronic inflammatory disease typically involving the face, neck, upper torso and shoulders and characterized by comedones (blackheads and whiteheads), oily skin, and inflammatory papules, pustules, cysts, or nodules.

Prevalence and Risk Factors

Affecting 40 to 50 million people in the United States, acne is the most common skin condition. It is predominantly a disease of teenagers and affects boys more commonly than girls. Resolution typically occurs by age 25 years. Adult acne occurs less often and is more common in women.¹ Mechanical or frictional forces (frequent washing, headgear, hats) and occlusion (cosmetics, hair products) can aggravate or induce acne. Numerous medications can produce acneiform eruptions (corticosteroids, anabolic steroids, anticonvulsants, lithium, potassium iodide, bromides, and isoniazid). Chloracne, a subtype of acne, occurs after exposure to chlorinated aromatic hydrocarbons.

Pathophysiology and Natural History

Acne is a follicular disease consisting of a comedonal and inflammatory stage. Defective keratinization produces a hyperkeratotic plug that blocks the opening of the pilosebaceous unit, forming a comedo. Seborrhea (increased sebum production) dilates the follicle and leads to subsequent bacterial overgrowth. Propionibacterium acnes, a colonizer of the follicle, proliferates, leading to leukocyte invasion and rupture of the follicle. The follicular contents and bacterial metabolites produce an inflammatory response, forming papules and pustules. Androgens, mainly dehydroepiandrosterone sulfate (DHEAS), stimulate sebaceous gland enlargement and secretion, which exacerbate the cycle.² Postinflammatory hyperpigmentation and scarring are common residua.

Signs and Symptoms

Acne often begins with open and closed comedones (whiteheads and blackheads) followed by inflammatory papules and pustules on the face, neck, chest, back, and shoulders (Fig. 1). Occasionally cysts and nodules are also present. Most patients have increased sebum production and oily skin.

Acne severity is commonly categorized as³:

• Mild: Comedones and some papules or pustules
• Moderate: Several papules, pustules, and comedones with increased truncal involvement
• Moderately severe: Many papules, pustules, and comedones; nodules; and widespread involvement (face, chest, shoulders, and back)
• Severe: Nodules and cysts

Acne conglobata is a severe form of truncal acne characterized by deep inflammatory cysts and nodules, often with interconnecting sinuses and fistulas (Fig. 2). Acne conglobata with systemic involvement, including fever, arthralgias, and leukocytosis, is referred to as acne fulminans.

Inflammatory and traumatized disease often yields hyperpigmentation and scarring, most commonly on the cheeks with an ice-pick or atrophic appearance. These residual changes are usually permanent but become less apparent with time.

Acne can affect a patient’s self-esteem, confidence, and sense of well-being. Some patients become depressed.

Diagnosis

Acne is a clinical diagnosis. Evaluation should include inquiry about current and previous treatments, cosmetics, and systemic medications. In female patients, hirsutism, menstrual irregularities, androgenic alopecia, perimenstrual flares, and recalcitrant or late-onset acne should suggest the possibility of androgen excess.

Laboratory tests are usually not necessary. However, signs of androgen excess deserve further evaluation for elevated serum DHEAS and free testosterone.

The differential diagnosis of acne includes rosacea, acneiform drug reactions, folliculitis, gram-negative folliculitis, and pseudofolliculitis (ingrown hairs).

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Summary

• Acne is a common, benign disease of the pilosebaceous apparatus.
• Acne is characterized by comedones, papules, and pustules in teenagers and young adults.

Treatment

The American Academy of Dermatology’s 2007 guidelines of care for managing acne vulgaris outline a multitiered approach to therapy tailored to the individual patient based on lesion type and severity.⁴ Box 1 gives recommended treatment guidelines.

Topical retinoids are a mainstay of treatment, reducing follicular obstruction in comedonal and inflammatory acne. Several formulations are available as creams and gels: tazarotene (Tazorac), tretinoin (Retin-A, Avita, Retin-A Micro), and retinoid-like adapalene (Differin). Nightly application of a thin film of medication is preferred but can lead to dryness and irritation. Implementing the medication three or four times weekly and increasing to nightly as tolerated enhances compliance. If irritation occurs, use should be decreased.

Benzoyl peroxide is an important acne therapy with its bactericidal, anti-inflammatory, and comedolytic properties. It is generally well tolerated and may be the most cost-effective acne treatment. Benzoyl peroxide is available in varying concentrations from 2.5% to 10% and as washes, gels, and cleansing pads. Its use helps to minimize antimicrobial resistance.⁵

Topical antibiotics, such as clindamycin 1% or erythromycin 2%, are helpful in inflammatory disease. However, given the increasing rates of bacterial resistance they should not be used as monotherapy. Combined use with a benzoyl peroxide prevents bacterial resistance, and a benzoyl peroxide or topical retinoid makes them more effective.³ Other topical agents, such as azelaic acid and products containing salicylic acid, sulfur, or sodium sulfacetamide, have minimal efficacy.

Most patients benefit from combination treatment using two or three agents. For mild to moderate acne, benzoyl peroxide and a topical retinoid with or without a topical antibiotic are often used. To facilitate treatment and patient compliance, combined formulations are available, such as benzoyl peroxide and clindamycin (Duac, BenzaClin) tretinoin and clindamycin (Ziana) & benzoyl peroxide & adapelene (Epiduo).

For more severe or extensive inflammatory acne, a systemic antibiotic is often warranted in addition to a benzoyl peroxide and/or topical retinoid. Doxycycline 100 to 200 mg/day, minocycline 100 to 200 mg/day, or tetracycline 500 mg to 1 g/day are effective options.⁴ Side effects are relatively uncommon, although gastrointestinal distress and vaginal candidiasis are possible. Doxycycline is a photosensitizer, and minocycline can induce pigmentation, dizziness, and a systemic lupus erythematosus (SLE)–like syndrome. These antibiotics should be avoided in children younger than 9 years, because dental or skeletal abnormalities can develop. Typically prescribed for rosaeia, submicrobial doxycycline (Oracea) 40 mg daily has anti-inflammatory properties and minimizes the potential for bacterial resistance. Sustained-release weight based minocycline (Solodyn) has exhibited good efficacy with minimal put Solodyn prior to oracea side effects. Alternatives to tetracycline include trimethoprim-sulfamethoxazole and erythromycin. Maximum improvement should not be expected for at least 3 months, regardless of the antibiotic chosen.³

For some women, hormonal therapy with low-progestin oral contraceptives or antiandrogenic agents can enhance treatment. FDA-approved oral contraceptives for acne include those containing norgestimate with ethinyl estradiol (Ortho Tri-Cyclen) and norethindrone acetate with ethinyl estradiol (Estrostep).⁴ Drospirenone with ethinyl estradiol (Yasmin, YAZ) has also been used effectively (Author’s first choice). Spironolactone (Aldactone), an antihypertensive with antiandrogenic properties, has been effective in some women by decreasing DHEAS.⁶

For severe or extensive disease, isotretinoin (Accutane), a vitamin A derivative, at a dose of 0.5 to 2 mg/kg per day for 20 weeks may be necessary. Potential side effects include skin dryness, bone and muscle pain, ocular dryness, headaches, pseudotumor cerebri, mood instability including depression, hyperlipidema, transaminitis, and teratogenicity. Highly regulated by the FDA, isotretinoin requires enrollment in a national registry, close follow-up including pregnancy testing, and sexual abstinence or two forms of birth control.

Adjunctive therapeutic measures include intralesional corticosteroids for inflammatory cysts and nodules, chemical peels (glycolic and salicylic acids), comedo extraction, photodynamic therapy (PDT), and diode (smooth beam) or pulsed-dye laser therapy. If postinflammatory hyperpigmentation is present the patient should avoid sun exposure and liberally use sunscreen to prevent further darkening.

Acneiform eruptions from the use of occlusive products, mechanical forces, corticosteroid application, or a medication reaction often respond to simply discontinuing the offending agent.

Despite the lack of a cure, acne can be minimized with early and thoughtful treatment, and most patients ultimately do well. Any treatment regimen deserves at least 6 to 8 weeks of consecutive, diligent treatment to assess clinical responsiveness.³

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Summary

• Benzoyl peroxide or a topical retinoid, or both, are the first-line therapy for mild acne.
• Moderate to severe inflammatory acne often requires a systemic antibiotic.
• Severe and scarring acne might require isotretinoin.

Prevention and Screening

Acne cannot be prevented, but it can be minimized by therapy.

Considerations in Special Populations

Treatment should be minimized or avoided during pregnancy and is often limited to topical or oral erythromycin and azelaic acid. Epileptic and bipolar patients can develop severe acneiform eruptions secondary to their medications.

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Rosacea

Definition

Rosacea is a chronic inflammatory disease characterized by easy flushing, persistent erythema on the central face with telangiectasias, and occasional flares of inflammatory papules and pustules.

Prevalence and Risk Factors

Rosacea affects approximately 14 million Americans and primarily occurs in middle-aged, fair-skinned adults of northern European heritage. It has a female predominance, but men more commonly develop phymatous rosacea (rhinophyma).⁷

Besides a genetic predisposition, disease-aggravating factors include spicy foods, alcohol, caffeine, especially hot coffee or tea, exercise, stress, and extremes of temperature.

Pathophysiology and Natural History

The pathophysiology of rosacea remains unclear, although genetic predisposition and vascular reactivity are likely factors involved. Persistent disease often leads to sebaceous hyperplasia and soft tissue hypertrophy (phymatous rosacea).

Signs and Symptoms

Rosacea is a polymorphic disease often divided into four subtypes that commonly overlap (Table 1 and Figs. 3 and 4).^{7, 8} Unlike acne, seborrhea and comedones do not occur. Ocular rosacea may be subtle, exhibiting only ocular dryness and a foreign body sensation.

Diagnosis

Rosacea is a clinical diagnosis. The patient with rosacea deserves inquiry regarding frequency of flushing, possible triggers, and eye symptoms including dryness, irritation, and redness. Laboratory tests are usually not necessary unless lupus erythematosus, another connective tissue disease, or carcinoid syndrome enters the differential diagnosis. Physiologic flushing can mimic erythematotelangiectatic rosacea and can actually precede rosacea. The differential diagnosis of rosacea includes chronic sun damage, chronic use of topical corticosteroids, seborrheic dermatitis, carcinoid syndrome, mastocytosis, and some connective tissue diseases, such as SLE, dermatomyositis, and mixed connective tissue disease.⁸

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Summary

• Rosacea is a polymorphic disease characterized by facial erythema with telangiectasias, papules, and pustules.
• Rosacea is often exacerbated by alcohol, caffeine, spicy foods, exercise, stress, and extremes of temperature.

Treatment

The treatment of rosacea depends on the disease subtype (see Table 1).⁹ Erythematotelangiectatic rosacea responds well to vascular laser therapy. Beta-blockers can decrease the frequency and severity of flushing. For inflammatory disease, with papules or pustules, metronidazole 0.75% or 1% gel or cream, sodium sulfacetamide and sulfur agents, and azelaic acid are effective therapies.

Some patients, especially those with moderate to severe papulopustular, phymatous, or ocular disease, should receive oral antibiotics, such as doxycycline 100 to 200 mg/day, minocycline 100 to 200 mg/day, or tetracycline 250 mg to 1 g/day. Submicrobial doses of doxycycline, (Oracea) 40 mg daily, have also shown promising results from the anti-inflammatory properties of the drug while minimizing the potential for antibacterial resistance. For phymatous rosacea, especially rhinophyma, surgical treatment with ablative laser, dermabrasion, or heated scalpel excision can help to restore the normal skin contours.

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Summary

• Rosacea therapy is often multifactorial.
• Laser therapy is used for telangeictasias.
• Metronidazole, sodium sulfacetamide and sulfur combinations, azelaic acid, or oral antibiotics are used for the inflammatory papules and pustules.

Prevention and Screening

Rosacea can be minimized by avoiding its known triggers: alcohol, caffeine, and spicy foods. Therapy is directed at the telangiectasias and inflammatory papules and pustules.

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