Several skin conditions are more common in darker skin tones. This can be due to the differences in cutaneous structure and function, which can result in skin conditions with distinct presentations and varying prevalence.
PIH is a reactive pigmentation of the skin that occurs as a consequence of skin inflammation. Common causes include acne, eczema, psoriasis, accidental burns, and insect bites but it may also occur after chemical peels and laser treatments.
It is more common in people with a darker skin tone and it can be very distressing for those affected by the PIH. In almost all cases, PIH tends to improve spontaneously but PIH on the legs tends to improve much slower and may in fact persist for years.
Basic simple measures like sun avoidance, sun protection, and sunscreens are essential for all cases. Topical treatments would include products containing the following ingredients: Hydroquinone, Retinoids, Azelaic acid, Vitamin C, Niacinamide, Kojic acid, Tranexamic acid, and Arbutin.
This is common in women with a darker skin tone, especially between the ages of 20-40 years. Common trigger factors include sun exposure, hormonal factors such as taking an estrogen-containing oral contraceptive, and pregnancy.
There are essentially three types of melasma namely:
Epidermal: This is where the excess pigment is in the epidermis.
Dermal: This is where the excess pigment has fallen from the top layer of the skin into the dermis.
Mixed: This is where you get a mixture of the epidermal and dermal forms of melasma. The mixed form is the most common.
The epidermal form of melasma is the easiest to treat as it is superficial. It may disappear completely just with sun avoidance and using a high factor, broad-spectrum sunscreen.
Unfortunately, deep dermal melasma is very difficult to treat and can persist for many years.
This is where lifelong, year-round sun protection is essential. Wearing a broad-brimmed hat in the sun and being meticulous about the regular application of a high factor, broad-spectrum sunscreen that includes the ingredients that block out Visible Light (VL). It may be necessary to consider stopping oestrogen-containing oral contraceptives.
Topical treatments are very similar to the treatment of PIH as listed above.
Medical micro-needling and fractional laser can also benefit but make sure these treatments are performed by those with experience in these treatments and who understand the risks to darker skin.
Hypertrophic and Keloid Scars
The below scars are more common in persons with a darker skin tone.
→ A Hypertrophic scar is a raised, red scar that does not extend beyond the margins of the original wound.
→ A Keloid scar is a raised lesion that extends beyond the borders of the original wound.
Common sites for both these types of scars to develop are the upper chest and back above the nipple line, along the jawline, and the ears.
If a person is prone to keloid formation they should avoid unnecessary surgery to these high-risk sites, one example is to avoid ear piercings.
Early effective treatments would include Micropore tape to be applied immediately after the sutures have been removed from a surgical wound. A good quality silicone gel that is not too greasy should be applied but it should also allow a high factor, broad-spectrum sunscreen to be applied on top of the gel, especially in sun-exposed areas. If a good quality sunscreen is not applied, you may be left with a pigmented scar.
If the scar is more established and thick, a cortisone injection into the scar can flatten the scar but may leave it still looking red with broken veins (telangiectasia). If the scar is flat and red, then Intense Pulse Light (IPL) can be useful to reduce the redness. If the scar is flat but pigmented, prescription topical Hydroquinone will lighten the pigmentation.
This is a mechanical folliculitis which is more common in men of African ancestry, where after a close shave the hair follicle retracts, and when it grows out it curls back on itself penetrating the skin causing local trauma and possible infection.
Common sites include the beard area and the nape of the neck in men but it can also occur in the bikini line and legs in women. Pseudofolliculitis may lead to post-inflammatory hyperpigmentation (PIH) as well as keloid formation. A specific sub-type called Acne Keloidalis Nuchae occurs in the nape of the neck, especially of African men.
Treatment would include allowing all the hairs to grow out i.e. grow a beard and if this is not cosmetically desirable, then trim the hair with an electrical clipper and leave a stubble. Avoid a close shave especially by pulling on the skin. If the hair is dark, laser hair removal is an excellent option. For the inflamed lesions one can use a topical spot treatment containing Azelaic acid, Tea tree oil, or Salicylic acid.
Acral Lentiginous Melanoma
This sub-type of melanoma accounts for less than 5% of all melanomas. It is however the most common type of melanoma that occurs in people of a darker skin tone and who are at lower risk for the more sun-related melanoma subtypes. It can occur on the palms of the hands, on the soles of the feet, and under the nails.
The cause of Acral LentigInous Melanoma is not clear but it could be due to repetitive trauma to these areas and be possibly due to thermal injury to the soles of the feet i.e. walking barefoot on a hot surface like hot sand.
Unfortunately, because one does not generally relate a malignant melanoma to a person with a darker skin type, ALM is often only diagnosed late with a poor prognosis. Therefore, if you have a darker skin tone and notice an enlarging freckle on the palms of your hands, on the soles of the feet, or under the nails, please consult your local Dermatologist. It is interesting to note that the musician, Bob Marley, died at the age of 36 years of an Acral Lentiginous Melanoma.