Pigmentary disorders refers to all skin disorders that result from pigmentation issues. This includes both excessive and lack of pigment conditions. Pigment is called melanin in Latin and is produced through a specialised cell in the skin called the melanocyte. The number of melanocytes is more or less constant. Melanin is produced through an enzymatic process converting the amino acid tyrosine to melanin. Once produced melanin is then stored in small packets called melanosomes which are then transferred to nearby skin cells through specific melanocytes finger-like projections. The amount of melanin that is produced and transferred will ultimately determine our skin colour. Ultraviolet light is one of the key stimulants to the melanocytes leading to increased melanin production.
Pigmentary disorders with excessive pigmentation relate either to increased number of melanocytes such as brown birthmarks or an increase in the production of pigment as a result of excessive sun exposure or various inflammatory conditions. Examples are melasma, post-inflammatory hyperpigmentation or the pigmentation which is observed in common sun damage, referred to as photodamage.
Skin conditions that present clinically with lack of pigmentation include vitiligo and some skin diseases that result in either temporary or permanent loss of melanin such as leukoderma and pityriasis versicolor. Vitiligo is a relatively common condition in which the immune system targets one’s own melanocytes. Treatment is with light exposure, anti-inflammatory topical creams and in some cases melanocytes transfer performed surgically.
Pigmentary disorders with excessive melanin can be treated with pigment-specific lasers that target the melanin and breaks it as well as the use of creams that slow down or block the conversion of tyrosine to melanin. These topical creams are called lightening creams or pigment inhibitors and may required to be used for a prolonged period. During any form of treatment the use of sun protection is advised to limit any potential melanocyte stimulation.
In all pigmentary disorders an accurate diagnosis is essential prior to commencing the treatment and in some cases further tests may be required to establish this. The different treatments available should be discussed with the dermatologist outlining the prognosis.
Dr. Firas Al-Niaimi has published many articles related to pigmentary disorders and these publications can be found in the publications section of the website.