Learn about why dark spots develop after scene lesions go away in darker skin


Rebecca Quinonez
AUTHOR

Raja Sivamani, MD MS AP
EDITOR
Skin pigmentation is one of the most variable and distinguishing factors in humans. With the ever-growing cultural diversity in the U.S., becoming familiar with skin conditions and their presentation of various skin pigmentation is key to this growing field of dermatology.
In the case of acne, it is reported to be one of the more prevalent dermatologic conditions in people of color. The causes of acne in darker skin does not differ from that in those with lighter skin;[1] however, the question that should be asked is: How is acne different in darker skin?
Darker Pigmentation
Darker skin has a greater production of melanin, synthesized by pigment producing cells in the epidermis known as melanocytes. Interestingly, there exists a direct correlation between the geographical distribution of UV radiation and skin pigmentation.[2] A greater degree of melanin is a form of adaptation and serves as a natural form of sun protection.[2] It turns out, people with darker skin seek dermatologists when they have changes in their skin that lead to skin conditions or changes with darker or lighter pigment.[1]
Inflammation and Pigmentation
Acne is the consequence of various factors, such as increased production of oils from the skin’s oil glands (known as sebocytes), clogged pores, and bacterial overgrowth in the pores.[3] Eventually, the body reacts to these “offending agents” by releasing inflammatory signals as a protective mechanism. The skin reacts to inflammation by producing more of the melanin pigment. The melanin is then either transferred to the surrounding cells or is lost to the dermal second layer of the skin, thus causing the darkened pigmentation (known as hyperpigmentation) in acne.[4] As a result, dark spots known as post inflammatory hyperpigmentation (PIH) are often seen in areas of acne inflammation and is more common in darker skin types compared to Caucasian patients.[5]
PIH typically forms after an acne outbreak, although it is also seen along with active acne lesions. The healing process for PIH is somewhat unique to every individual but typically takes months to years to go away. It is described as blue-gray or dark brown lesions.[6] Keloid scarring, although rarer, can develop in the African American population,[7] due to excessive scarring that occurs after acne.
Acne Treatment Approach is Different
Special considerations must be taken during the treatment of acne in patients of darker skin tones. The steps for treating acne in those with darker skin are the following:
- The first strategy is to treat any active lesions of acne.[8] This step is similar in those with or without darker skin. Controlling the acne is an important first step.
- The second strategy is to reduce the formation of dark spots. This is accomplished by reducing the production of the melanin pigment. One example is the use of a topical medication known as azelaic acid. Topical azelaic acid 20% cream is FDA approved for the treatment of acne[9] but also blocks the pigment-making enzyme tyrosine from making melanin.[10]
- The third strategy is to diligently protect the skin from ultraviolet light and sun exposure, both of which stimulate the production of the melanin pigment. For those with darker skin color and acne, sun and ultraviolet light exposure can lead to more post inflammatory hyperpigmentation (dark spots).
Pomade Acne
One variant of acne that is seen more commonly among the African American population is pomade acne. Pomade acne, typically found along the hairline areas of the African American population, is due to the common use of hair products (sometimes known as pomades).[11] Pomades block and plug hair follicles, often causing acne along the hairline.[12] Decreasing the use, or finding a less dense hair product, along with the management of acne, may reduce the severity and potential complications of this type of acne.
* This blog is for general skin, beauty, wellness, and health information only. This post is not to be used as a substitute for medical advice, diagnosis, or treatment of any health condition or problem. The information provided on this Website should never be used to disregard, delay, or refuse treatment or advice from a physician or a qualified health provider.
REFERENCES
1. Davis EC, Callender VD. A review of acne in ethnic skin: pathogenesis, clinical manifestations and management strategies. J Clin Aesthet Dermatol. 2010;3(4):24-38; PMID: 2921746.
2. Jablonski NG, Chaplin G. Human skin pigmentation as an adaptation to UV radiation. Proc Natl Acad Sci USA. 2010;107(2):8962-8968. PMID: 3024016.
3. Kurokawa I, Danby FW, Ju Q, et al. New developments in our understanding of acne pathogenesis and treatment. Exp Dermatol. 2009;18(10)821-832;PMID: 19555434.
4. Makino ET, Kadoya K, Sigler ML, et al. Development and clinical assessment of a comprehensive product for pigmentation control in multiple ethnic populations. J Drugs Dermatol. 2016;15(12)1562-1570. PMID: 28095579.
5. Bhate K, Williams HC. Epidemiology of acne vulgaris. Br J Dermatol. 2013;168(3):474-485; PMID: 23210645.
6. David EC, Callender VD. Postinflammatory hyperpigmentation: a review of the epidemiology, clinical features, and treatment options in skin color. J Clin Aesthet Dermatol. 2010;3(7):20-31; PMID: 20725554.
7. Shah SK, Alexis AF. Acne in skin of color: practical approaches to treatment. J Dermatolog Treat. 2010;21(3):206-211. PMID: 20132053
8. Rutledge BJ. Adjust Treatment of Skin Disorders in Black Patients. Internal Medicine News. 2008 Feb 15;41(4):13.
9. Link to research. Accessed March 26, 2017.
10. Nazzaro-Porro M. Azelaic acid. J Am Acad Dermatol.1987;17(6):1033-1041; PMID: 2963038.
11. Williams DF, Kaplan DL. Common dermatoses of black skin: a guide to recognition and therapy. Consultant. 1998; 189.
12. Taylor SC, Heath C. Cultural competence and unique concerns in patients with ethnic skin. J Drugs in Dermat. 2012; 11(4):460-465. PMID: 22453582

Rebecca Quinonez
AUTHOR

Raja Sivamani, MD MS AP
EDITOR