Acne usually appears in adolescence and can persist in adulthood. Men and urbanites are more affected. About 20% of patients affected by the condition develop severe acne, which can result in scarring. Patients of African descent tend to develop severe acne, while mild acne is more common in those of European descent. In general, populations with darker skin also tend to develop hyperpigmentation.1
Most mild-to-moderate acne cases (see Table 1) can be treated in primary care, while patients with severe or recalcitrant acne, who do not respond to first-line treatments, have severe scarring, or psychological or physical distress, should be referred to a specialist physician.1,4
Grading of acne
Acne is a chronic inflammatory condition resulting in pimples, erythema, scars, and hyperpigmentation in areas like the face, neck, and upper torso. Acne presents as polymorphic lesions starting with comedones.1,2
Diagnosis is clinical and routine microbiologic testing is not recommended in the evaluation and management of acne but is recommended for patients who exhibit acne-like lesions suggestive of Gram-negative folliculitis.5,6
Although routine endocrinologic evaluation (eg for androgen excess) is not recommended for the majority of patients with acne, it is recommended for patients with additional signs of androgen excess. Patients with abnormal test results, or in whom there is a persistent concern for a hormonal disorder, should be further evaluated by an endocrinologist.5
The use of a grading/classification scale (encompassing the numbers and types of acne lesions as well as disease severity, anatomic sites, and scarring) may be useful when having to decide on a management approach. Acne is graded as:1,5
Grade 1: Comedones. They are of two types, open and closed. Open comedones are due to plugging of the pilosebaceous orifice by sebum on the skin surface. Closed comedones are due to keratin and sebum plugging the pilosebaceous orifice below the skin surface.
Grade 2: Inflammatory lesions present as a small papule with erythema.
Grade 3: Pustules.
Grade 4: Many pustules coalesce to form nodules and cysts.
Guideline recommendations for the management of acne
The 2021 National Institute for Health and Care Excellence (NICE) and the American Academy of Dermatology (AAD) guidelines recommend the following treatment for patients with acne:5,6
Acne scars result from an altered wound healing response to cutaneous inflammation. Inadequate deposition of collagen leads to the formation of an atrophic scar while, if the healing response is excessive, a hypertrophic scar is formed.8,9
Patients at highest risk of developing scars are those:10
- With inflammatory (swollen, reddish, and painful) acne: These often include acne cysts and nodules. This type of acne tends to penetrate deep into the skin, which damages the skin.
- Who delays or does not treat inflammatory acne: The longer a person has inflammatory acne, the greater the risk of scarring.
- Who picks, squeezes, or pops acne: This increases inflammation, which increases the risk of scarring.
- Has a blood relative who developed acne scars: Genes play a large role.
Aggressive, early treatment of active acne remains the best way to prevent or limit acne-related scarring.9
Most patients (80%–90%) develop atrophic scars. Atrophic scars (appear indented and develop when the skin cannot regenerate tissue correctly) are associated with a loss of collagen. Other types include hypertrophic (appears in an area of increased induration and often dyspigmentation over the site of a wound) and keloid (thick raised tissue) scars.8
Icepick scars are the most common form of atrophic scars (60%-70%). These narrow, <2mm, V-shaped epithelial tracts have a sharp margin that extends vertically to the deep dermis or subcutaneous tissue. Icepick scars can be treated with skin resurfacing therapies depending on their depth.9
Boxcar scars are the second most common type of atrophic scars (20%-30%). These scars are wider (1.5mm-4mm) and appear as round-to-oval depressions with sharply demarcated vertical edges. Shallow boxcar scars (0.1mm-0.5mm) can be treated with skin resurfacing therapies, while deep boxcar scars (≥0.5mm) are resistant to this type of treatment.9
Rolling scars (15%-20%) are the widest and may reach up to 5mm in diameter. Fibrous anchoring of the dermis to the subcutis results in superficial shadowing and an undulating appearance of the scars. Treatment must focus on the correction of the subdermal component.9
Expectation management is important when treating patients. Complete resolution of acne scarring is the exception rather than the rule.9
The effective management of scars requires a patient-centred, stepwise approach:9
Step 1: Address residual erythema if present.
Step 2: Address generalised atrophic scars, tailoring the treatment method to the predominant scar type present.
Step 3: Any remaining scars should be treated according to the most suitable method for the individual scar. Surgical techniques and injectable fillers may suffice for solitary scars. However, most patients require field treatment for broad areas of scarring, for which lasers and other resurfacing agents remain the mainstay of treatment.9
Acne is a common, inflammatory disease with a general onset in adolescence. Acne negatively impacts the quality of life of patients and may result in psychological distress. Therefore, guidelines recommend that all patients presenting with acne should be treated. A number of treatment options are available and treatment decisions should be guided by the type and severity of acne. Some patients are at high risk of developing scars. The risk can be mitigated by the early and aggressive treatment of acne. A number of therapies are also available for patients with scars. Expectation management is important when dealing with a patient with scars because complete resolution is the exception rather than the rule.
- Sutaria AH, Masood S, Schlessinger J. Acne Vulgaris. [Updated 2023 Feb 16]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK459173/
- American Academy of Dermatology Association. Acne can affect more than your skin. Available from: https://www.aad.org/public/diseases/acne/acne-emotional-effects#:~:text=In%20research%20studies%2C%20people%20with,makes%20them%20feel%20on%20edge.
- Xu SMM, Zhu YMM, Hu HMB, et al. The analysis of acne increasing suicide risk. Medicine, 2021.
- Moosa AS, Lim SF, Koh YLE, Aau WK, Tan NC. The management of acne vulgaris in young people in primary care: A retrospective cohort study. Front Med (Lausanne), 2023.
- Zaenglein AL, Pathy AL, Schlosser BJ, et al. Guidelines of care for the management of acne vulgaris. JAAD, 2016.
- National Guideline Alliance (UK). Management options for moderate to severe acne – pairwise comparisons: Acne vulgaris: management: Evidence review F2. London: National Institute for Health and Care Excellence (NICE); 2021 Jun. (NICE Guideline, No. 198.) Available from: https://www.ncbi.nlm.nih.gov/books/NBK573054/
- NICE. Guidance - Isotretinoin for severe acne: uses and effects. Available from: https://www.gov.uk/government/publications/isotretinoin-for-severe-acne-uses-and-effects/isotretinoin-for-severe-acne-uses-and-effects
- Bikash C and Sarkar R. Topical management of acne scars: The uncharted terrain. JCD, 2023.
- Connolly D, Vu HL, Mariwalla K, Saedi N. Acne Scarring-Pathogenesis, Evaluation, and Treatment Options. J Clin Aesthet Dermatol, 2017.
- American Academy of Dermatology. Acne scars: who gets and causes. Available from: https://www.aad.org/public/diseases/acne/derm-treat/scars/causes