Sunday, June 17, 2007

Pigmentation Disorders

Skin pigmentation disorders and irregularities are common. Hyperpigmentation problems are particularly prevalent and many are associated with aging. While the triggers may vary, hyperpigmentation occurs when pigment-producing cells (melanocytes) become more active than normal, which leads to the production and deposition of more pigment (melanin). Conversely, hypopigmentation occurs when melanocytes are destroyed or silenced. Following are the most common pigmentation problems.

Hyperpigmentation Disorders

Age spots / sun spots (solar lentigines): Age spots/sun spots (solar lentigines) are pigmented skin blemishes associated with aging, sun damage and, to a lesser degree, other forms of skin damage. Age spots range in color from light brown to black and are predominantly located in areas exposed to the sun, such as hands, face, and arms. It is not entirely clear how sun damage triggers age spots: most likely, UV radiation produces mutations, local inflammation and other changes that increase local proliferation of melanocytes and/or activate melanin-producing genes. Sun/Age spots are harmless but may be cosmetically frustrating.

Freckles : Freckles are small, pigmented spots containing more melanin than the surrounding skin. Freckles are not caused by aging and/or sun damage. As opposed to age spots, freckles tend to fade with age. Sun exposure, while not a cause of freckles, typically makes freckles much more prominent. Freckles are found mainly in fair skinned people and tend to run in families. The cause of freckles appears to be largely genetic. Freckles are not considered a skin disorder and are harmless. Some consider them a cosmetic nuisance.

Melasma / Chloasma: Melasma is a condition characterized by increased tan-like skin pigmentation typically having uneven, patchy distribution. Chloasma is a variant of melasma occurring mainly in women and associated with increased levels of certain hormones. Chloasma may be triggered by pregnancy, oral contraceptives and occasionally other hormonal imbalances.

While hormonal changes seem to be the most common cause of melasma / cholasma, other factors may have a role. In particular, a combination of sun damage and certain ingredients found in deodorants, toiletry and other personal care products may result in melasma - apparently due to local sensitization of melanocytes.

In some cases, melasma resolves on its own if the underlying hormonal imbalance is removed (e.g. when hormonal contraceptives are replaced by a non-hormonal method or after childbirth). If the cause is non-hormonal, avoiding sun exposure and reducing/eliminating suspect skin/body care products may improve melasma. In persistent cases, various methods of skin lightening may be used.

Hypopigmentation disorders: Hypopigmentation is far less common that hyperpigmentation. Hypopigmentation occurs when pigment-producing cells (melanocytes) are either destroyed or stunned into inactivity. This generally occurs either due to serious skin damage (e.g. a burn) or due to an autoimmune disease where the immune system erroneously attacks melanocytes

Prevention of pigmentation disorders: Most hyperpigmentation problems are either caused or exacerbated by sun exposure. Hence sun protection is important for preventing hyperpigmentation. Other measures of skin protection should also help. Women with history of chloasma may be able to prevent recurrence by using non-hormonal birth control methods. However, such step should be discussed with a physician and balanced against the disadvantages of the non-hormonal alternatives.

Treatment of pigmentation disorders: Hyperpigmentation problems may be improved or eliminated by a variety of treatments, including topical lightening agents, laser / intense pulsed light, cryotherapy and chemical peels.

Treating hypopigmentation may be a greater challenge. Hypopigmentation after a burn or similar skin injury may resolve itself over time as melanocytes migrate to the damaged area. Current treatments for vitiligo are of limited effectiveness. For many people, camouflaging hypopigmentaed areas with sunless tanning products represents a viable alternative

Next Article: About Cellulite………….

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