Although in the usual language we call pimples a wide variety of acne lesions, they have different medical names, have different modes of formation, a different evolution, and can be treated through various treatment schemes. Knowing the type of acne lesions is important because it helps us understand the formation and evolution of acne, helps us assess the severity of acne and its prognosis. It also helps us to choose, under the guidance of a specialist, the most appropriate treatment.
Blackheads are the most common acne lesions. They can be found in two forms: closed comedones or white dots and open comedones or black dots. It is formed by the blockage of pores by accumulations of dead cells and sebum. There are also a variety of cosmetics and makeup that can cause this type of lesion, which is why they are listed as comedogenic.
Comedones can exist as such, causing comedonian acne, or they can be associated with other types of acne lesions. Comedonian acne is a mild form of acne that can be treated with over-the-counter cosmetics. In general, comedones do not cause scarring but can progress to inflammatory acne lesions.
Among the most effective active ingredients in the treatment and prevention of comedones are retinoids (retinol, retinaldehyde), azelaic acid, alpha, and beta hydroxy acids. It is also important to check the list of ingredients of cosmetics to exclude the comedogenic ones. Blackhead extraction can be done in medical offices, not at home, and can be useful in some cases.
The Papules are part of the category of inflammatory lesions found in acne and represent small swellings of the skin up to 5 mm, pink or reddish, which can sometimes be painful. The Pustules are swellings of the skin under 5mm, but larger than closed comedones, white in color, with a purulent content, and which may be surrounded by redness.
Papules and pustules are formed by the evolution of comedones. The accumulation of impurities and dead cells is accentuated to the point where the walls of the pilosebaceous follicle (pore) rupture and cause inflammation in the surrounding tissues. Propionibacterium acnes, the bacterium responsible for the appearance of inflammatory acne, is also involved in the production of inflammation. This type of lesion is present in papulo-pustular acne, a form of moderate to severe acne. Papules and pustules can cause scarring.
The treatment of papulo-pustular acne should be initiated and guided by a dermatologist. For the treatment of this type of lesions are used topical preparations containing retinoids (tretinoin, adapalene), benzoyl peroxide, antibiotics, and combinations thereof. If a good response is not obtained after a topical treatment, applied correctly and long enough, or if the form of papulo-pustular acne is severe, the dermatologist will prescribe a prescription with antibiotics or isotretinoin for internal administration. In some cases, the papules and pustules may indicate a hormonal disorder, which is why additional investigations and hormonal treatment will be recommended.
Nodules are papule-like inflammatory lesions, but larger in size, hard in consistency, and located deeper in the skin. They deform the skin more, are painful, and may be accompanied by more redness. Cysts are deep, large lesions with a purulent content. Cysts and nodules are inflammatory lesions present in severe forms of acne, called nodulo-cystic. Scars occur in their healing process. This type of lesion requires treatment with internal administration (isotretinoin, antibiotics).
Post-acne scars can be divided into red spots, brown spots, atrophic scars, and, less often keloid scars.
Red spots appear when inflammatory lesions persist for a longer period. The redness is due to small blood vessels in the skin that have dilated in response to the present inflammation. Redness may be on the skin or may be associated with atrophic scars. The redness left after the pimples have healed will go away on its own, but this can occur after a period of several months or even years. The resolution of this situation can be accelerated by the use of creams with niacinamide, linoleic acid, and oleic acid, physical and chemical sunscreens.
Brown spots are medically called postinflammatory hyperpigmentation. They appear after the healing of papules and pustules and are more common among people with darker skin, if the acne lesions have been squeezed or if the skin has been exposed to the sun while the acne lesions were active. These are superficial signs and will go away on their own over time. As their fading may take several months, to speed up their healing, cosmetics with depigmenting or exfoliating effect (azelaic acid, kojic acid, vitamin C, phytic acid, alpha, and beta hydroxy acids) may be used together with creams with SPF 30 or 50 during the day. Superficial peels or laser treatments can be performed in medical offices.
Atrophic scars are usually produced by nodules and cysts. Depending on their appearance, atrophic scars can be of 3 types. Rolling scars are rounded depressions of the skin, with a large surface area and variable depth, the skin having a wavy appearance. Boxcar scars have straight edges and various geometric shapes. Ice-pick scars are depressions of the skin with a small but deep surface as if the skin is pricked with a needle; are the most difficult type of scars to treat. Atrophic scars require complex treatments, in several sessions, in which laser procedures, deep peels, microneedling, subcision, and radiofrequency can be combined.
Dr. Alexandra Bațani, dermatologist
DermaExpert Clinic, Bucharest