The color of the skin is determined by the presence of a pigment called melanin. The skin cells producing melanin are called melanocytes. Increased number or activity of melanocytes results in hyperpigmentation of the skin.
Other factors also play a role in determining the color of the skin. These are vascularity or blood supply of the skin, presence of other skin pigments like carotene and thickness of the skin’s upper layer (stratum corneum).
Causes of hyperpigmentation can include hormonal changes, acne, trauma to skin, heredity, and sun exposure.
Skin pigmentation disorders usually affect a part of the skin. In some conditions, they can affect the entire skin.
Post Inflammatory Hyperpigmentation
Skin darkening that follows injury and inflammation is referred to as post inflammatory hyperpigmentation. It often follows conditions like acne, psoriasis, atopic and contact dermatitis, chicken pox lichen planus, trauma, and fixed-drug eruptions. The resultant hyperpigmentation at the site of injury usually lasts for months or years. Post Inflammatory conditions could also result in hypopigmentation in some cases.
In this kind of hyperpigmentation, a tan or a brown patch is seen on the sun-exposed areas of the skin, most commonly the face and forearms. It is also seen in pregnant women; however it often times disappears after delivery. Some cases of melasam can have a dermal and epidermal component and be more resistant. It is sometimes seen in patients taking oral contraceptives or anticonvulsants like phenytoin. Melasma can be treated topically, with hydroquinone, kojic acid, azaleic acid, retinoids, and in some cases with laser therapy. Sunscreens help to prevent the development of melasma to some extent. Resistant melasma is a condition that we can control but cannot cure. Any source of heat can trigger melasma.
Solar lentigines are also called liver spots. They are small hyperpigmented spots that erupt after shorrt-term or chronic exposure to ultraviolet light. They are primarily seen on the face, hands, forearms, chest, back and shins. They are more commonly seen in Whites or Asians.
Ablative or topical therapy is used in treating this kind of hyperpigmentation. Ablative therapies include chemical peels, cryotherapy and laser therapy.
Ephelides or freckles are the small sharp macular lesions of red to light brown color seen on the face, neck, chest and arms. They usually occur during childhood after sun exposure. They usually fade in the winter. They can be treated using local medications or laser therapy.
This kind of hyperpigmentation is seen at birth or early in life. They are tan or brown in color, and are often found on the trunk. It can be effectively treated by laser therapy and surgery. More than 6 such lesions should raise the suspicion of the presence of disease conditions like tuberous sclerosis, Albright syndrome, or Fanconi anemia
- IPL (Photofacial) – Treatment with intense pulsed light, or a Photofacial, is frequently recommended to treat hyperpigmentation.
- Chemical peel – A variety of chemical peels can benefit in the treatment of hyperpigmentation.
- Laser Treatments – A variety of laser resurfacing treatments may be performed to reduce hyperpigmentation. These include ablative and non ablative laser treatments.
- Topical skin lightening products – Products containing skin lightening ingredients, such as hydroquinone, retinoids, kojic acid, azaleic acid , and Vitamin C are often used to reduce hyperpigmentation.
- Platelet Rich Plasma can be of benefit in some pigmentation disorders