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AlexanderSalava

Acne

Essentials

  • The diagnosis is based on clinical presentation and patient history.
  • Treatment is chosen according to the subtype and severity of the patient's acne.
  • The treatment response usually requires time and the patient should be motivated towards a long term therapy.
  • The condition may cause cosmetic problems and it may have an impact on psychosocial health.

Epidemiology and aetiology

  • A common skin disease, with lifetime prevalence of 60-80%
  • In puberty acne is more common in males and in adulthood in females; acne may first manifest itself in adulthood
  • Endogeneous and multifactorial
  • Hereditary tendency; in a great majority of cases the disease can be encountered in close family members, especially in severe acne.

Clinical picture

  • A chronic skin disease with a fluctuating clinical course
  • Usually most prevalent on the face, upper back and chest.
  • May leave disfiguring scars and cause psychosocial problems.
  • Scar formation is individual; more common in severe acne.
  • Divided into subtypes, which may co-exist.
    • Comedonal acne (acne comedonica; pictures 1 2 3)
      • The main skin changes encompass both open and closed comedones. Only slight inflammatory changes on the skin.
    • Common acne (acne vulgaris), also known as papulopustular acne (pictures 45 6)
      • Lesions are mainly red papules and pustules, but also comedones occur.
    • Cystic acne (acne cystica; pictures 7 8 9 10 11)
      • Larger inflammatory nodules and deep burrowing lesions, often painful and sore, can be seen on the skin, in addition to comedones, papules and pustules.
    • Other variants of severe cystic acne
      • Acne conglobata is the chronic form of cystic acne, and it is associated with larger burrowing nodules and comedones. In addition to the typical sites of predilection for common acne lesions, these also appear on the buttocks and flexural areas. Double comedones are typical; one sebaceous gland duct opens onto the skin via two orifices.
      • Acne fulminans is a severe acne with rapid onset, which may include, in addition to severely inflamed and ulcerative acne lesions, also fever as well as joint and muscular pains.

Diagnosis

  • Diagnosis is clinical.
  • The presence of comedones (blackheads = open comedones, whiteheads = closed comedones; picture 2) suggests acne.
  • The patient should also be asked about factors that aggravate acne.
    • External factors (hygiene products and cosmetics including oily lotions, mechanical occlusion, rubbing, hot environment in some cases, sweaty work, holidays and sun exposure)
    • Internal factors (glucocorticoids, lithium, iodine, antiepileptic medication, testosterone, anabolic streroids)
    • Rare diseases causing hyperandrogenism (polycystic ovarian syndrome [PCOS] Polycystic Ovary Syndrome (PCOS); congenital adrenal hyperplasia, non-classic form)

Investigations

  • In a female patient, in the absence of other signs of hyperandrogenism (hirsutism, abnormal menstrual bleeding, infertility) no hormone testing is usually required.
  • Acne starting at a very young age might be a sign of an endocrine disease.
    • If hyperandrogenism is strongly suspected, the serum levels of free testosterone may be tested in a female patient.

Differential diagnosis

  • Rosacea Rosacea: pustules, mainly affects the central portion of the face, telangiectasias, flush reaction
  • Perioral dermatitis Perioral Dermatitis: often around the mouth, only papules
  • Folliculitis Skin Abscess and Folliculitis: single pustules around the beard area or more widespread pustules on the upper body
  • Acneiform drug reactions and rare rashes that resemble acne

Topical treatment Topical and Oral Treatments in People with Acne Vulgaris

  • Skin lesions are slow to heal. The topical treatment of the skin takes time, and the patient must be motivated to the treatment.
  • The skin is washed in the morning and evening with water and soap or with an antibacterial wash solution.
  • Treatment is chosen according to the subtype of the patient's acne.
  • Medicinal ointment is usually applied in the evening to all areas where acne has occurred.
  • The efficacy of treatment does not often become apparent until after several weeks, and consequently the patient may abandon the treatment too early as inefficient.
  • Topical treatment should be continued until the skin condition has subsided; the treatment is then, as required, continued long term, for example twice a week (using a medicinal ointment suitable for maintenance therapy, see below).
  • Medicinal ointments may cause skin dryness and redness particularly at the early stages of the treatment. Should this occur, the product should be applied more infrequently, the treatment should be stopped for a while or another topical product tried.
  • To reduce irritation a basic topical ointment with high water content may be applied over the medicinal ointment after a few minutes; the irritation usually subsides as the skin becomes accustomed to the topical skincare product.
  • Treatment may be started with a lower concentration and/or the patient may be advised to wash the medicine off the skin after a few hours in the early phase (for 2-3 weeks).
  • An effective and suitable topical treatment can usually be found by trying out different products. Each of these should be tried for a period of about 1-2 months (their effect takes time to appear).
  • There is no strong evidence on the difference in effectiveness of various products (the products below are shown in alphabetical order).
  • In comedonal acne, topical antimicrobial therapy is not recommended.
  • Acne vulgaris
  • Maintenance therapy

Systemic treatment Topical and Oral Treatments in People with Acne Vulgaris

  • Indicated in widespread or severe acne vulgaris, or when correctly applied topical therapy alone has not proved sufficient.
  • May also be started in milder cases if the patient, for example, is concerned about acne induced scarring.
  • Topical treatment must continue during systemic treatment. Antimicrobial therapy alone, either systemic or topical, is not recommended in the treatment of acne; it should always be combined with topical treatment with either vitamin A (adapalene or tretinoin), benzoyl peroxide or azelaic acid, or a combination gel (adapalene and benzoyl peroxide, benzoyl peroxide and clindamycin, or tretinoin and clindamycin).
  • Systemic treatment is carried out with doxycycline 50-100 mg once daily, lymecycline 150-300 mg once or twice daily, or tetracycline 250-500 mg once or twice daily (no established differences in effectiveness).
    • Tetracyclines (particularly doxycycline and tetracycline) may sensitise the patient to sunlight.
    • Tetracyclines should not be given to children younger than 8 years, nor during pregnancy or breastfeeding.
    • If tetracyclines cannot be used, drugs of the macrolide group have been used (evidence is scarce in the treatment of acne): for example erythromycin 250-500 mg twice daily, azithromycin 500 mg once daily (3-day course that is repeated once or twice in a month), roxithromycin 150-300 mg once daily.
  • It is advisable to continue with systemic treatment until the acne has clearly settled down; this usually takes 1 to 3 months. The daily dose may be reduced when the acne has settled down.
  • Except in exceptional cases, the monitoring of laboratory parameters during the treatment is not necessary.

Other treatments

  • Hormonal contraception and hormonal therapy in women (see also article Hormonal contraception Hormonal Contraception)
    • Combined contraceptives (COCs) (pills, skin patch, vaginal ring)
      • Due to their oestrogen, all COCs may reduce greasiness of the skin and acne. The effect is individual.
      • Evidence in the treatment of acne is available particularly for the combinations of dienogest and ethinyloestradiol as well as drospirenone and ethinyloestradiol.
      • Luteal hormones differ between them with regard to their androgenic properties. Additional effect on acne may be obtained by selecting products that contain an antiandrogenic progestin or a progestin that is as mildly androgenic as possible.
      • Remember the contraindications of COCs Hormonal Contraception.
    • Antiandogenic COCs
    • COCs with low androgenic activity
    • Progestin contraception
      • Low-dose drospirenone (antiandrogenic) is usually suitable for a patient with acne. It may also have a suppressing effect on acne.
      • Other progestins used for contraception are mildly androgenic and, depending on the patient, may worsen acne. In such a case, change of product may be considered (different product, a product with less androgenic activity, different contraception method).
      • Progestin pills: mildly androgenic desogestrel or norethisterone are suitable for many patients with acne.
      • Hormonal intrauterine devices (IUD) contain mildly androgenic levonorgestrel but are suitable for many patients with acne. A more suitable alternative for some patients with acne may be an IUD with lower levonorgestrel dose or a copper IUD.
      • Subcutaneous conctaceptive implants contain mildly androgenic levonorgestrel and even more mildly androgenic etonogestrel; these are suitable for many patients with acne.
    • Where contraception is required, the antiandrogenic properties of combined oral contraceptives can be exploited (cyproterone acetate, drospirenone or desogestrel and oestrogen) Combined Oral Contraceptive Pills (Cocs) for Treatment of Acne.
    • Low dose oral progestogen only contraceptives with no androgenic properties are also suitable in acne.
  • Photo and laser therapies
    • There is no strong evidence on the efficacy of photo therapies (e.g. PDT, blue light, infrared) and laser therapies in acne, but they may be beneficial to some patients as additional therapyLight Therapies for Acne.
  • Acne scarring
    • Treatment of acne scars with laser or dermabrasion should not be considered until the active disease has become totally quiescent. An attempt may be made to flatten prominent keloid scars with glucocorticoid injections or cryotherapy Interventions for Acne Scars.
  • Collaboration with a cosmetician (beautician)
    • Correctly carried out deep skin cleansing by a cosmetician is often of benefit in the treatment of comedonal acne. A cosmetician will also give information about the correct make-up to use and skin cleansing.
  • There is no evidence on special diets (e.g. with low glycaemic index), herbal medicines, vitamins, trace elements or CAM treatments (e.g. acupuncture) in the treatment of acne Complementary (Cam) Therapies for Acne Vulgaris.

Specialist consultation

  • A dermatologist should be consulted in severe forms of acne (cystic acne, for example)
  • In severe acne with a significant number of inflammatory lesions leading to scarring, isotretinoin therapy is used, guided by a dermatologist.
    • Can also be started if the patient fails to respond to all other, properly carried out, treatment options or if acne causes scarring or if it recurs despite adequate treatment.
    • Teratogenicity is a particular problem. Women of childbearing age must use effective contraception for at least one month before starting treatment and for one month after the end of treatment (two methods, e.g. hormonal contraception or an IUD and a condom).
    • Before treatment is started the following laboratory parameters should be checked, this can be done by the referring physician in primary care: ALT, cholesterol, triglycerides and, in women, additionally the serum level of human chorionic gonadotropin (qualitative).
      • A negative pregnancy test must always be obtained before treatment and 5 weeks after the end of treatment, also during the treatment if considered necessary.
      • Liver enzymes and lipid values must be checked before the treatment is started
    • Acne that starts at a very young age may need the involvement of an paediatrician or a paediatric endocrinologist.

References

  • Liu H, Yu H, Xia J, et al. Topical azelaic acid, salicylic acid, nicotinamide, sulphur, zinc and fruit acid (alpha-hydroxy acid) for acne. Cochrane Database Syst Rev 2020;(5):CD011368. [PubMed]
  • Yang Z, Zhang Y, Lazic Mosler E, et al. Topical benzoyl peroxide for acne. Cochrane Database Syst Rev 2020;(3):CD011154. [PubMed]
  • Samuels DV, Rosenthal R, Lin R, et al. Acne vulgaris and risk of depression and anxiety: A meta-analytic review. J Am Acad Dermatol 2020;83(2):532-541. [PubMed]
  • Williams NM, Randolph M, Rajabi-Estarabadi A, et al. Hormonal Contraceptives and Dermatology. Am J Clin Dermatol 2020;():. [PubMed]
  • Costa CS, Bagatin E, Martimbianco ALC, et al. Oral isotretinoin for acne. Cochrane Database Syst Rev 2018;(11):CD009435. [PubMed]
  • Thiboutot DM, Dréno B, Abanmi A, et al. Practical management of acne for clinicians: An international consensus from the Global Alliance to Improve Outcomes in Acne. J Am Acad Dermatol 2018;78(2 Suppl 1):S1-S23.e1. [PubMed]
  • Vallerand IA, Lewinson RT, Farris MS, et al. Efficacy and adverse events of oral isotretinoin for acne: a systematic review. Br J Dermatol 2018;178(1):76-85. [PubMed]
  • Barbaric J, Abbott R, Posadzki P, et al. Light therapies for acne: abridged Cochrane systematic review including GRADE assessments. Br J Dermatol 2018;178(1):61-75. [PubMed]
  • Hauk L. Acne Vulgaris: Treatment Guidelines from the AAD. Am Fam Physician 2017;95(11):740-741. [PubMed]
  • Bienenfeld A, Nagler AR, Orlow SJ. Oral Antibacterial Therapy for Acne Vulgaris: An Evidence-Based Review. Am J Clin Dermatol 2017;18(4):469-490. [PubMed]
  • Fiedler F, Stangl GI, Fiedler E, et al. Acne and Nutrition: A Systematic Review. Acta Derm Venereol 2017;97(1):7-9. [PubMed]
  • Stuart B, Maund E, Wilcox C et al. Topical preparations for the treatment of mild-to-moderate acne vulgaris: systematic review and network meta-analysis. Br J Dermatol 2021;185(3):512-525. [PubMed]
  • Samuels DV, Rosenthal R, Lin R et al. Acne vulgaris and risk of depression and anxiety: A meta-analytic review. J Am Acad Dermatol 2020;83(2):532-541. [PubMed]
  • Liu H, Yu H, Xia J et al. Evidence-based topical treatments (azelaic acid, salicylic acid, nicotinamide, sulfur, zinc, and fruit acid) for acne: an abridged version of a Cochrane systematic review. J Evid Based Med 2020;13(4):275-283. [PubMed]

Evidence Summaries