Pigmentation Disorders

Pigmentation disorders usually manifest as patchy skin discoloration with irregular borders mainly affecting face, neck, decolletage and hands.

Melasma (or Chloasma when present during pregnancy) is one of the most common pigmentation disorders.

It presents as patches of skin discoloration developing gradually over time. Most often it manifests as changes in the colour of pigmentation of the face mainly affecting cheeks, forehead and nose. Melasma can cause sufferers psychoemotional distress and interfere with normal social interaction as people may feel self-conscious of their uneven skin tone.

The skin disorder affects primarily women and all skin types can be affected but melasma is more common in darker skin complexions.

Various factors have been associated with melasma. Some of them include:

  • Genetic predisposition
  • Hormonal causes such as pregnancy, contraceptives, stimulation for I.V.F.
  • Exposure to sun can trigger or may act as an aggravating factor for melasma.
  • Post Inflammatory Hyperpigmentation (PIH) secondary to ordinary conditions such as acne or injury to the skin resulting from sunburns, surgery or cosmetic procedures such as chemical peels, dermabrasion, lasers and cryotherapy (liquid nitrogen treatments).
  • Thyroid and Addison’s disease
  • Other aggravating factors include certain cosmetic products e.g. exfoliating lotions and bleaching agents especially when used without sun protection, a wide range of medication such as corticosteroids, systemic retinoids or other systemic photosensitizing drugs such as certain antibiotics.

Skin colouring

Melanin, apart from being an excellent photoprotectant, is also the primary determinant of skin colour. There are two types of melanin; eumelanin and pheomelanin. The enzyme tyrosinase is required for melanocytes to produce melanin from the amino acid tyrosine.