Skin is the largest organ of the body. It is made up of two layers, the upper 'epidermis' and the lower 'dermis'. The epidermis contains certain cells called melanocytes, which produce a pigment called 'melanin'. The colour of skin depends on melanin. The thickness of epidermis and vascularity of the epidermis are other factors affecting the colour of the skin.
Disorders of Pigmentation
Freckles: These are small, flat round lesions, which occur in the lighter skin types. They tend to turn darker in summer and lighter in winter. Causative factors are genetics and sun exposure.
Treatment: Various peels like glycolic and TCA help in lightening freckles. For more stubborn variety light systems like the IPL and lasers like the Q switched NdYag and KTP can be used. Minimal sun exposure, sunscreen and skin brightening and lightening cosmeceuticals will help to keep the pigment at bay.
Solar Lentigines: These are flat pigmented 1to 3cm lesions present mainly on sun exposed areas. They start to appear in the third decade of life.
Treatment: Everyday use of sunscreen is an absolute must. TCA peels, Intense Pulsed Light systems and lasers such as KTP and Q Switched NdYag can remove them completely.
Melasma: Is a stubborn pigmentation seen mainly in women. Occasionally, men too get affected by this condition. It is characterized by a patchy tan or brown discoloration that occurs over the upper lip, cheeks, forehead, chin and bridge of the nose. The areas affected are bilateral and frequently symmetrical.
The majority of cases are due to sun exposure, hormonal changes such as pregnancy, menopause, oral contraceptive pills and familial predisposition.
Treatment: Melasma is a stubborn condition and requires multiple sessions of treatments. Often 2 or more treatments are combined to give better results. Epidermal melasma (superficial) responds better and faster to treatment. Sunscreens form the most essential part of treatment of melasma. A variety of depigmenting agents such as Hydroquinone, Kojic acid, Glycolic acid, Retinoic acid etc can aid in the treatment of melasma.
In addition to this, superficial peels such as Glycolic acid peels and Salicylic acid peels; moderately deep peels such as 50% glycolic acid and TCA, as well as deeper peels such as Cosmelan can be used to treat melasma. Lasers such as Q switched NdYag show limited results. Light systems like the IPL, as well as Microdermabrasion, Meso therapy has also been successful in treating melasma depending upon the depth and intensity of pigment.
Some of the dermatological disorders are:
Pigmented Contact Dermatitis
This condition can occur both in men and women. The pigmentation occurs due to frequent and repeated contact with small amounts of sensitizing allergens primarily present in cosmetic and textile materials. It is characterized by a diffuse to reticulated (lace like) pattern of hyper pigmentation and its colour may vary from slate gray, gray brown to blue brown. The sites of Pigmented Contact Dermatitis depends on the allergen responsible and in case of cosmetics, it frequently involves the face and neck. Another common area is the underarms.
Pigmented Photo Contact Dermatitis
This condition occurs with musk containing fragrances, medications like anti diabetic medications, and certain antibiotics; Photodynamic substances in cosmetics on exposure to sunlight leave behind a reticulated pigmentation. Avoidance of the incriminating agents and lightening agents and procedures are part of the treatment plan.
Lichen Planus Pigmentsosus
This is a pigmentary disorder commonly seen in India. It involves mainly the face, neck, and upper limbs but can be more widespread. The pigmentation varies from slate gray to brownish black. It can be diffused or reticulate in pattern. This is a rather difficult condition to treat and it may take years for the pigment to fade.
This kind of pigmentation is very common in Indians. It usually involves both the arms, and the back. The common causes of this pigmentation are friction, hot showers, and use of loofah and bathing brushes. The pigmentation is usually brownish black with reticulate pattern.
All these conditions require a medical evaluation. Strict use of sunscreen and avoidance of triggering factors is the mainstay of treatment followed by applications of various skin lightening products and treatments to lighten he pigmentation.
Melasma is a skin condition presenting as brown patches on the face of adults. Both sides of the face are usually affected. The most common sites of involvement are the cheeks, bridge of nose, forehead, and upper lip.
Who gets melasma?
Melasma mostly occurs in women. Only 10% of those affected are men. Dark-skinned races, particularly Hispanics, Asians, Indians, people from the Middle East, and Northern Africa, tend to have melasma more than others.
What causes melasma?
The precise cause of melasma is unknown. People with a family history of melasma are more likely to develop melasma themselves. A change in hormonal status may trigger melasma. It is commonly associated with pregnancy and called chloasma, or the "mask of pregnancy." Birth control pills may also cause melasma, however, hormone replacement therapy used after menopause has not been shown to cause the condition.
Sun exposure contributes to melasma. Ultraviolet light from the sun, and even very strong light from light bulbs, can stimulate pigment-producing cells, or melanocytes in the skin. People with skin of color have more active melanocytes than those with light skin. These melanocytes produce a large amount of pigment under normal conditions, but this production increases even further when stimulated by light exposure or an increase in hormone levels. Incidental exposure to the sun is mainly the reason for recurrences of melasma. Any irritation of the skin may cause an increase in pigmentation in dark-skinned individuals, which may also worsen melasma. Melasma is not associated with any internal diseases or organ malfunction.
How is melasma diagnosed?
Because melasma is common, and has a characteristic appearance on the face, most patients can be diagnosed simply by a skin examination. Occasionally a skin biopsy is necessary to differentiate melasma from other conditions.
How is it treated?
While there is no cure for melasma, many treatments have been developed. Melasma may disappear after pregnancy, it may remain for many years, or a lifetime. Sunscreens are essential in the treatment of melasma. They should be broad spectrum, protecting against both UVA and UVB rays from the sun. A SPF 30 or higher should be selected. In addition, physical sunblock lotions and creams such as zinc oxide and titanium oxide, may be used to block ultraviolet radiation and visible light. Sunscreens should be worn daily, whether or not it is sunny outside, or if you are outdoors or indoors. A significant amount of ultraviolet rays is received while walking down the street, driving in cars, and sitting next to windows.
Any facial cleansers, creams, or make-up which irritates the skin should be stopped, as this may worsen the melasma. If melasma develops after starting birth control pills, it may improve after discontinuing them. Melasma can be treatedwith bleaching creams while continuing the birth control pills.
A variety of lightening creams are available for the treatment of melasma. These creams do not "bleach" the skin by destroying the melanocytes, but rather, decrease the activity of these pigment-producing cells. Over-the-counter creams contain low concentrations of hydroquinone, the most commonly-used depigmenting agent. This is often effective for mild forms of melasma when used twice daily. A dermatologist may prescribe creams with higher concentrations of hydroquinone. Normally, it takes about three months to substantially improve melasma. Creams containing tretinoin, steroids, and glycolic acid are available in combination with hydroquinone to enhance the depigmenting effect. Other medications which have been found to help melasma are azelaic acid and kojic acid. It is important to follow the directions of your dermatologist carefully in order to get
the maximum benefit from your treatment regimen and to avoid irritation and other side effects. Remember, a sunscreen should be applied daily in addition to the lightening cream. Some lightening creams are combined with a sunscreen.
Chemical peels, microdermabrasion, and laser surgery may help melasma, but results have not been consistent. These procedures have the potential of causing irritation, which can sometimes worsen melasma. Generally, they should only be used by a dermatologist in conjunction with a proper regimen of lightening creams and prescription creams tailored to your skin type. People should be cautioned against non-physicians claiming to treat melasma without supervision because complications can occur. Chemical peels, microdermabrasion, and laser surgery may help melasma, but results have not been consistent. These procedures have the potential of causing irritation, which can sometimes worsen melasma. Generally, they should only be used by a dermatologist in conjunction with a proper regimen of lightening creams and prescription creams tailored to your skin type. People should be cautioned against non-physicians claiming to treat melasma without supervision because complications can occur.