Comedonal acne

Medically reviewed by The Dermatologists and written by Dr. Alexander Börve

Comedonal acne is a subtle yet significant skincare concern many people face. In fact, according to a study done in 2021, the International Journal of Women’s Dermatology reports 79.2% of pre pubertal acne detected were comedonal acne.^[1] It is one of many presentations of acne vulgaris, with the characteristic feature of numerous “comedones”.

What is Comedonal Acne?

Comedonal acne is characterized by the presence of comedones, which are small, non-inflammatory bumps that occur when hair follicles become clogged with oil, dead skin cells, and other debris.^[2] This process is called ‘comedogenesis’, and could be the result of cells in your pilosebaceous ducts (tiny canal in the skin that connects the hair follicle to the sebaceous gland) proliferating too quickly.^[3] Initially these are not visible to the naked eye, therefore given the name ‘microcomedones’, but later become bigger and visible forming the characteristic comedones.^[4]

What does comedonal acne look like?

Chances are, you would not recognize these comedones as acne most of the time because they do not look like your typical acne. They can present in one of two ways; open comedones (blackheads) or closed comedones (whiteheads).

Also, they can be single or multiple depending on the type of comedones present and the location in the body. Black heads are usually few in number whereas white heads are often seen clustered together in bigger numbers.^[5] White heads are commoner than black heads.^[2]

Image of forehead with comedonal acne, showing multiple small white bumps known as whiteheads, white due to trapped oil and skin cells beneath the skin’s surface

Also, in areas like face, back and chest where oil production from sebaceous glands is high, there will be clusters of comedones rather than a single comedo.

Comedonal acne on the face, with visible inflammation, red slightly raised spots (papules), and pus-filled lesions (pustules)

Blackheads usually don’t cause inflammation unless you disturb them by squeezing. So, it’s important you do not to touch or pick at your skin, to prevent irritation and worsening of the condition. Because of this milder presentation and the lack of symptoms of typical acne, especially pain and redness, people often do not recognize comedonal acne.

Types of Comedonal Acne

When the hair follicles are closed, they form skin-colored or whitish bumps called closed comedones or whiteheads. As comedones grow, the follicular openings may widen, leading to open comedones or black heads, with a dark or black spot at the center due to melanin buildup.^[4]

Microcomedones are in the initial stage, which is identified when a biopsy from the normal looking acne prone skin is checked under light microscope for histology. In other words, this stage cannot be seen from the naked eye. Macrocomedones are those that measure > 1mm in size.^[4]

Giant Comedones are exceptionally large comedones that can reach several millimeters in size. They are often seen in adolescents and young adults and can occur on the face, neck, or upper trunk. In rare cases, there is evidence of giant comedones being associated with basal cell cancer.^[4]

Solar Comedones are comedones that develop as a result of prolonged sun exposure, particularly in individuals with fair skin. They appear as widespread yellowish tint accompanied by significant deep wrinkles, furrows and large, open blackheads on sun-damaged, thinning skin, especially symmetrically distributed around the temples and around the eyes.^[4]

There is another entity called ‘missed comedones’, where even regular blackheads and whiteheads might not be recognized if the correct technique is not followed when examining. In every patient, it’s important to gently pull the skin and use bright light at a low angle. Stretching the skin reveals about 20% more comedones that would otherwise go unnoticed.^[4]

Causes for Comedonal Acne

As explained above, the reason behind comedones is the clogged pores that normally secrete sebum. This can result from a number of causes. Genetic predisposition, altered lipids in sebaceous secretions, hormonal fluctuations, and environmental influences, like humidity or exposure to pollutants, play pivotal roles in its development.^[3] Increased sebum production, abnormal shedding of skin cells, and hormonal imbalances lead to follicular obstruction, giving rise to blackheads and whiteheads. Cosmetic ingredients like isopropyl myristate, lanolin, or oleic acid, along with excessively oily bases in topical products, contribute to comedogenicity.^[4]

Diagnosis of Comedonal Acne

Diagnosing comedonal acne primarily relies on visual examination of the skin. Healthcare providers identify the presence of characteristic blackheads and whiteheads, often clustered on the face, chest, or back. It is important to follow correct examination techniques and have good lighting in order to make the accurate diagnosis. However, if typical treatments fail to yield results, conditions such as folliculitis, seborrheic dermatitis, fungal infections, or rosacea may need to be ruled out through further evaluation and diagnostic tests to ensure accurate management. Additional tests like microbiological and endocrine testing to detect certain hormone levels will be used to differentiate comedonal acne from these conditions that might mimic it.^[4]

Treatment for Comedonal Acne

Treatment for comedonal acne encompasses various options, ranging from over-the-counter (OTC) to prescription medications. OTC choices often include topical treatments containing ingredients like azelaic acid or benzoyl peroxide, which help unclog pores and reduce inflammation.^[4] For more severe cases, healthcare providers may prescribe stronger medications, such as retinoids or hormonal therapy.

Retinoids are crucial in treating comedonal acne due to their ability to promote skin cell turnover, preventing the buildup of dead skin cells within hair follicles, and reducing the formation of new comedones. This is termed as ‘comedolytic effect’ of retinol, which is achieved by creating a vitamin A excess in the epithelial cells and inhibiting the abnormal cell differentiation.^[4] Adapalene is the recommended over isotretinoin or tretinoin for treatment of comedonal acne.^[4]

The timeline for treatment efficacy varies from person to person, depending on factors such as the severity of the acne and individual response to medication. While some individuals may notice improvements within a few weeks, others may require more extended treatment durations. Therefore, it is essential to adhere to the prescribed treatment regimen consistently and avoid discontinuing treatment prematurely.

There are some surgical options for treating persistent comedonal acne. Emily M.W. and Emmy M.G. report a case of repeated manual extraction of macrocomedones while the patient remained on isotretinoin treatment, which led to a significant improvement in the lesions, with no scarring remaining afterward.^[4] Other office procedures like fulguration (the destruction of small growths or areas of tissue using heat produced by high frequency electric currents with diathermy) and electrocautery are also practiced as treatment methods for comedonal acne.^[4]

Prevention of Comedonal Acne

Preventing comedonal acne involves adhering to a diligent skincare routine. Opt for non-comedogenic products to avoid pore-clogging ingredients. Maintain proper hygiene by washing your face twice daily with a gentle cleanser. After sweating, promptly cleanse the skin to prevent pore congestion. Choose lightweight, breathable makeup and remove it thoroughly before bedtime to prevent buildup. Consistency in these practices is key to minimizing comedonal acne outbreaks.

Conclusion

Comedonal acne is a type of mild and early-stage presentation of acne vulgaris. Understanding this condition involves recognizing its distinct characteristics and causes, such as excess oil production and follicular obstruction. Treatment options, including retinoids and proper skincare routines, target these underlying factors for clearer skin. Prevention strategies emphasize the use of non-comedogenic products and consistent hygiene practices. By addressing these aspects comprehensively, and consistently adhering to the treatment regime, you can effectively manage and minimize the impact of comedonal acne.