Description

• Acne vulgaris is a disorder of the pilosebaceous units. It is a chronic inflammatory dermatosis notable for open/closed comedones, papules, pustules, or nodules.
• System(s) affected: Skin/Exocrine

Geriatric Considerations
Favre-Racouchot syndrome: Comedones on face and head due to sun exposure

• May result in a flare or remission of acne
• Erythromycin can be used in pregnancy; use topical agents when possible.
• Isotretinoin is teratogenic; Class X
• Avoid topical tretinoin, although no good evidence exists that its use is teratogenic.
• Contraindicated: Isotretinoin, tazarotene, tetracycline, doxycycline, minocycline

• Neonatal acne (neonatal cephalic pustulosis) (1):
  • Newborn to 8 weeks, lesions limited to face
• Infantile acne:
  • Newborn to 1 year, lesions on face, neck, back, and chest
• Early childhood acne:
  • 1–7 years; rare, consider underlying hormonal pathology
• Preadolescent acne:
  • 7–11 years; common, 47% of children, usually due to adrenal awakening
• Do not use tetracyclines <8 years of age

Epidemiology

• Predominant age: Early to late puberty, may persist into 4th decade
• Predominant sex:
  • Male > Female (adolescence)
  • Female > Male (adult)

• ≈80–95% of adolescents affected. A smaller percentage will seek medical advice.
• 8% of adults aged 25–34; 3% at 35–44 years

Risk Factors

• Increased endogenous androgenic effect
• Oily cosmetics
• Rubbing or occluding skin surface (e.g., sports equipment such as helmets and shoulder pads), telephone, or hands against the skin
• Polyvinyl chloride, chlorinated hydrocarbons, cutting oil, tars
• Numerous drugs, including androgenic steroids (e.g., steroid abuse, some birth control pills)
• Endocrine disorders: Polycystic ovarian syndrome, Cushing syndrome, congenital adrenal hyperplasia, androgen-secreting tumors, acromegaly
• Stress
• High glycemic load diets may exacerbate acne.

• Familial association in 50%
• If a family history exists, the acne may be more severe and occur earlier.

Pathophysiology

• Immune changes and inflammatory responses may predate hyperkeratinization.
• Androgens (testosterone and dehydroepiandrosterone sulfate [DHEA]) stimulate sebum production and proliferation of keratinocytes in hair follicles.
• Keratin plug obstructs follicle os, causing sebum accumulation and follicular distention.
• Propionibacterium acnes, an anaerobe, colonizes and proliferates in the plugged follicle.
• P. acnes promotes chemotactic factors and proinflammatory mediators, causing inflammation of follicle and dermis.

Commonly Associated Conditions

• Acne fulminans
• Pyoderma faciale
• Acne conglobata
• Hidradenitis suppurativa
• Pomade acne
• SAPHO syndrome: Synovitis, acne, pustulosis, hyperostosis, osteitis
• PAPA syndrome: Pyogenic sterile arthritis, pyoderma gangrenosum, cystic acne
• Behçet syndrome
• Apert syndrome
• Dark-skinned patients: 50% keloidal scarring and 50% acne hyperpigmented macules

History

• Ask about duration, medications, cleansing products, stress, smoking, exposures, diet, family history.
• Females may worsen prior to menses.

Physical Exam

• Closed comedones (whiteheads)
• Open comedones (blackheads)
• Nodules or papules
• Pustules (“cysts”)
• Scars: Ice pick, rolling, boxcar, atrophic macules, hypertrophic, depressed, sinus tracts
• Grading system (American Academy of Dermatology, 1990):
  • Mild: Few papules/pustules; no nodules
  • Moderate: Some papules/pustules; few nodules
  • Severe: Numerous papules/pustules; many nodules
  • Very severe: Acne conglobata, acne fulminans, acne inversa.
• Most common areas affected are face, chest, back, and upper arms (areas of greatest concentration of sebaceous glands).

Diagnostic Tests and Interpretation

Lab
Only indicated if there are additional signs of androgen excess; if so: Free testosterone, DHEA-sulfate (DHEA-S), luteinizing hormone, and follicle-stimulating hormone (2)[A]

Differential Diagnosis

• Folliculitis: Gram negative and gram positive
• Acne (rosacea, cosmetica, steroid-induced)
• Perioral dermatitis
• Chloracne
• Pseudofolliculitis barbae
• Drug eruption
• Verruca vulgaris and plana
• Keratosis pilaris
• Molluscum contagiosum
• Facial angiofibromas
• Sarcoidosis
• Seborrheic dermatitis

Medication (Drugs)

• Keratinolytic agents (side effects include dryness, erythema, scaling, and photosensitivity; start with lower strength; increase as tolerated) (2,4)[A].

• Tretinoin (Retin-A, Retin A Micro, Avita): Apply at bedtime; wash skin and let skin dry 30 minutes before topical application:
  • Retin-AMicro and Avita are less irritating; produce less phototoxicity.
  • May cause an initial flare of lesions; may be eased by 14-day course of oral antibiotics.
• Adapalene (Differin): 0.1%, apply topically at night:
  • Effective; less irritation than tretinoin or tazarotene (4)[A]
  • May be combined with benzoyl peroxide.
• Tazarotene (Tazorac): Apply at bedtime:
  • Most effective and most irritating; teratogenic
• Azelaic acid (Azelex, Finevin): 20% topically, b.i.d.:
  • Keratinolytic, antibacterial, anti-inflammatory
  • Reduces postinflammatory hyperpigmentation in dark-skinned individuals
  • Side effects: Erythema, dryness, scaling, hypopigmentation
  • Less effective in clinical use than in studies
• Salicylic acid: Less effective than tretinoin
• Alpha-hydroxy acids: Available over-the-counter
• Topical antibiotics and anti-inflammatories (4)[A]:
  • Topical benzoyl peroxide:
    • Bactericidal through direct toxic effect
    • No P. acnes resistance noted
    • 2.5% as effective as stronger preparations
    • When used with tretinoin, apply benzoyl peroxide in morning and tretinoin at night
    • Side effects: Irritation; may bleach clothes
• Topical antibiotics (2,4)[A]:
  • Erythromycin 2%
  • Clindamycin 1%
  • Metronidazole gel or cream: Apply once daily.
  • Azelaic acid (Azelex, Finevin): 20% cream: Enhanced effect and decreased risk of resistance when used with zinc and benzoyl peroxide
  • Benzoyl peroxide-erythromycin (Benzamycin): Especially effective with azelaic acid
  • Benzoyl peroxide-clindamycin (BenzaClin, DUAC, Clindoxyl): Effective combined
  • Benzoyl peroxide-salicylic acid (Cleanse & Treat, Inova): Similar in effectiveness to benzoyl peroxide-clindamycin
  • Sodium sulfacetamide (Sulfacet-R, Novacet, Klaron): Useful in acne with seborrheic dermatitis or rosacea
  • Dapsone (Aczone) 5% gel: May cause yellow/orange skin discoloration when mixed with benzoyl peroxide
• Oral antibiotics (2,4)[A]: Use for at least 6–8 weeks after initiation, discontinue after 12–18 weeks duration:
  • Tetracycline: 500–2,000 mg/d b.i.d.–q.i.d.; high dose initially, taper in 6 months, as tolerated. Side effects: Photosensitivity, esophagitis:
  • Avoid use with antacids, iron
  • Both antibacterial and anti-inflammatory (5)
  • Minocycline: 50–200 mg/d, q.i.d.–b.i.d.; side effects include photosensitivity, urticaria, gray-blue skin, vertigo, autoimmune hepatitis, pseudotumor cerebri, lupuslike syndrome. May be more effective than tetracycline (2)[A],(6).
  • Doxycycline: 50–200 mg/d, given b.i.d.–q.i.d.; side effects include photosensitivity.
  • Erythromycin: 500–1,000 mg/d; given b.i.d.–q.i.d.; decreasing effectiveness as a result of increasing P. acnes resistance
  • Trimethoprim-sulfamethoxazole (Bactrim DS, Septra DS): 1 daily or b.i.d.
  • Azithromycin (Zithromax): 500 mg 3 days/week × 1 month then 250 mg every other day × 2 months
• Oral retinoids:
  • Isotretinoin (Accutane) (2,4)[A]: 0.5–2.0 mg/kg/d b.i.d.; 60–90% cure rate; usually given for 12–20 weeks; maximum cumulative dose = 120–150 mg/kg; 20% of patients relapse and require retreatment:
    • Side effects: Highly teratogenic, pancreatitis, hypertriglyceridemia, hepatitis, blood dyscrasias, hyperostosis, premature epiphyseal closure, night blindness, erythema multiforme, Stevens-Johnson syndrome, suicidal ideation, psychosis
    • Avoid tetracyclines or vitamin A preparations during isotretinoin therapy.
    • Monitor for pregnancy, CBC, lipids, and liver function tests at baseline and every month.
    • Should be registered member of manufacturer’s iPLEDGE program

• Isotretinoin is a teratogenic; Class X.
• Medications for women only:
  • Oral contraceptives (2,4)[A],(7):
    • Norgestimate/Ethinyl estradiol (OrthoTricyclen), norethindrone acetate/ethinyl estradiol (Estrostep), drospirenone/ethinyl estradiol (Yaz, Yasmin) are approved by US FDA for this indication.
    • Levonorgestrel/Ethinyl estradiol (Alesse) and most others are also effective.
  • Spironolactone (Aldactone); 25–200 mg/d; antiandrogen; reduces sebum production
  • Flutamide (Eulexin) 250–500 mg/d; potentially hepatotoxic

Additional Treatment

Acne hyperpigmented macules:

• Topical hydroquinones (1.5–10%)
• Azelaic acid (20%) topically
• Topical retinoids as, above
• Corticosteroids: Low dose, suppresses adrenal androgens (2)[B]
• Dapsone 5% gel (Aczone): Topical, anti-inflammatory use in patients >12 years

Consider referral/consultation to dermatologist:

• Refractory lesions despite appropriate therapy
• Consideration of isotretinoin therapy
• Management of acne scars

Light-based treatments:

• Ultraviolet A/Ultraviolet B (UVA/UVB), blue or blue/red light, pulse dye laser, KTP laser, infrared laser
• Photodynamic therapy for 30–60 minutes with 5-aminolevulinic acid × 3 sessions is effective for inflammatory lesions:
  • Greatest utility when used as adjunct to medications or in patient who can't tolerate medications

Complementary and Alternative Therapies

• Topical tea tree oil is effective, slow onset (2)[B].
• Nicotinamide 4% gel (Nicam): As effective as clindamycin in moderate inflammatory acne

Surgery/Other Procedures

• Comedo extraction after incising the layer of epithelium over comedo (2)[C]
• Incision and drainage for abscesses
• Inject large cystic lesions with 0.05–0.3 mL triamcinolone (Kenalog 2–5 mg/mL); use 30-g needle to inject and slightly distend cyst (2)[C].
• Acne scar treatment: Retinoids, steroid injections, cryosurgery, electrodessication, micro/dermabrasion, chemical peels, laser resurfacing

Follow-Up Recommendations

Use oral or topical antibiotics for 3 months; stop if inflammatory lesions resolve. Can switch abruptly from oral to topical without taper. Do not use topical and oral together.

• Pretreatment and monthly lipids, liver function tests, and pregnancy tests when on isotretinoin
• Consider antibiotic resistance (60% overall) or gram-negative folliculitis if treatment fails.

Diet

Special diets do not diminish acne (2)[B].

Patient Education

• There may be a worsening of acne during first 2 weeks of treatment.
• Results are typically seen after a minimum of 4 weeks.

Prognosis

Gradual improvement over time (usually within 8–12 weeks after beginning therapy)

Complications

• Acne conglobata: Severe confluent inflammatory acne with systemic symptoms
• Facial and psychological scarring
• Gram-negative folliculitis: Superinfection due to long-term oral antibiotic use; treatment with ampicillin, trimethoprim-sulfa, or isotretinoin

See Also

• Acne Rosacea
• Algorithm: Acne

ICD-9

706.1 Other acne

ICD-10

• L70.0 Acne vulgaris

SNOMED

• 88616000 Acne vulgaris (disorder)