Pigmentation disorders in Taiwanese skin: a clinical experience
Authors: Tsai T. F. 
Published: September 2010

Introduction

Difference in skin color is the most prominent features among different races. Skin of each ethnical group responds somewhat differently to the stimuli [1]. This unique feature of the skin is important in the management of skin diseases. Unlike the western worlds, a fair and uniform coloration is desirable by most women in Taiwan. Dyspigmentation, either in the form of hyperpigmentation or hypopigmentation is always more visible in the pigmented races, and results in greater psychosocial impacts among the affected individuals.

Hyperpigmentation disorders in Taiwan

The most common face and neck hyperpigmentation disorders in Taiwanese include melasma, freckles, solar lentigines, seborrheic keratosis, Ota nevus and nevus zygomaticus. Moreover, even common inflammatory or infectious disorders may result in very unsightly postinflammatory hyperpigmentation. Atopic dermatitis, for example, may cause red face syndrome and dirty neck syndrome. Riehl's melanosis is still occasional seen. Amyloidosis and lichen planus also rarely present as facial hyperpigmentation. The hyperpigmentation may be either nevoid or acquired, and even be iatrogenic. For example, a zebra‐like hyperpigmentation sometimes occur after intense pulsed light (IPL) therapy. Next to the face, hyperpigmentation of the dorsal hands is most disturbing, both to males and females. Hyperpigmentation of the forearms can be covered up by long‐sleeved dressings, but in the summer, this may also be very bothersome. Hyperpigmentation of specific sites including the nipples/areola, axillae, lips, genitalia and especially periorbital areas is sometimes disturbing, and poses therapeutic challenge. A pink nipple/areola is considered as a sign of virginity, and pink genitalia (in men, glans penis only) are also considered a symbol of youth and purity. Truncal dyspigmentation is usually better tolerated, but a change of leisure activity may be needed.

Other than melanin, hyperpigmentation may also result from iatrogenic pigment. Cosmetic tattoos of the eyebrows and eyelash lines are performed only by the tattoo artists, and may sometimes require removal. A special type of tattoo in Taiwan is done for political reason, and after the change of political milieu, removal of the tattoo is often inquired. And this is the only type of tattoo for which laser treatment is reimbursed by the medical insurance.

Dark face may also result from carotenemia and sallowness. Vegetarian diet is very common in Taiwan, and with the popularity of ‘healthy drinks’ containing carrot, papaya or tomato juice, it is becoming more common to see patients with carotenemia. The precise mechanism of sallowness is unknown, but a combination of decreased vascularity and a change in the quality of dermal collagen and/or elastin has been suggested.

Treatment of hyperpigmentation disorders

Many whitening ingredients can be seen in the cosmetics, but there are presently only six officially approved cosmetic whitening ingredients in Taiwan, i.e. kojic acid, arbutin, ascorbyl glucoside, magnesium ascorbyl phosphate, camomile and ellagic acid. Cosmetics not containing the above ingredients should not label whitening effects. Hydroquinone is the only whitening ingredient in drug category, and often used in conjunction with retinoic acid and steroid. Up to 4% of hydroquinone can be used. Hydroquinone is a very irritating chemical; however, no cases of exogenous ochronosis have been reported in Taiwan. Adulterated cosmetics containing drugs and even mercury are occasionally found on the market. Self‐application of home‐made topical whitening recipe is also very popular, and has resulted in an outbreak of contact leukomelanosis caused by the steamed leaves of Piper Betel [2]. A confetti hypopigmented spots within areas of pre‐existing hyperpigmentation is very characteristic. Because of the ready availability of most topical whitening preparation by the patients, whitening masks, chemical peeling [3] and instrumental whitening therapy using either iontophoresis or sonophoresis [4] are commonly provided in most private clinics, beauty saloons and hospitals. Electroporation is a recent addition to this category. Lasers and intense pulsed light are also used to treat hyperpigmentation other than melasma. It is important to warn the patients in advance the possibility of prolonged postinflammatory hyperpigmentation and even persistent hypopigmentation after treatment. Besides, systemic treatment is used as well, both in oral and intravenous forms. In the treatment of all types of facial hyperpigmentation, the importance of sunscreen is emphasized. Sunscreens with high SPF and adequate UVA protection are usually recommended. There is no regulation on the labeling of UVA protection and no capping for SPF value in Taiwan.

The treatment of pigmentation disorders in pigmented races is always challenging. For nevoid hyperpigmentation, destructive measures like lasers or IPL [5] can usually achieve satisfactory end results but repeated courses may be necessary. Acquired lesions like solar lentigines or freckles can also be treated as such, but recurrence is the rule despite vigorous or pain‐taking photoprotection. Medical treatment of hyperpigmentation is usually less than satisfactory and needs maintenance therapy. For lesions like melasma, medical treatment remains the only recommended therapy.

Other than cosmetic reason, many Chinese people are convinced that facial pigmentation reflects internal ‘disharmony’, most likely renal or hepatic disorders. ‘White’ traditional Chinese medicinal herbs are usually considered effective to treat the hyperpigmentation.

Hypopigmentation disorders

Compared with hyperpigmentation disorders, the available treatment for hypo‐ and de‐pigmentation disorders is relatively few. Idiopathic guttate hypopigmentation is the most common complaint followed by pityriasis alba and postinflammatory hypopigmentation. Reassurance is usually the only recommendation for the above conditions. Vitiligo, however, requires more aggressive early intervention. The diagnosis of vitiligo is often straightforward. However, special variants of vitiligo may pose diagnostic difficulty, such as the inflammatory or small macular types. On the other hands, diseases like imatinib mesylate may cause hypopigmentary conditions indistinguishable. And it is almost impossible to rule out chemical or contact leukoderma. This is the case for hair dye and paint‐on tattoo induced depigmentation. The treatment of vitiligo is often prolonged and complete repigmentation may often be a too optimistic goal. It is of paramount importance to look for early lesions by Wood's light when the treatment is only topical. Vitiligo is amenable to topical treatment of steroid, vitamin D, and newer immunomodulators (tacrolimus and pimecrolimus), often in combination with phototherapy. A topical antioxidant gel (Vitix®) is also used with some success in early facial lesions. Topical/systemic PUVA, narrow band UVB, and microphototherapy including X‐Trac and Blue Point are also available. Phototherapy is considered the gold standard of vitiligo therapy, but hyperpigmentation and photoaging is inevitable during the treatment and often discourages the patients from receiving the therapy. Systemic steroid is given to generalized vitiliginous patients who desire more aggressive therapy. For vitiligo universalis, depigmentation therapy of the few remaining normal skin often produces more cosmetically appealing result. For segmental lesions, low energy laser or superluminous diode is also effective [6]. Surgical treatment with suction blister graft, punch graft or autologous cultured melanocyte graft is used in segmental or stable generalized vitiligo [7].

Conclusion

Despite the availability of many new machines and chemicals used for pigmentary disorders, the therapeutic response is often less than satisfactory. Recent understanding of the pathophysiology of the skin pigmentary systems has indicated the need for different approaches than just developing stronger tyrosinase inhibitors for whitening effects. A holistic approach integrating the epidermal, dermal and systemic factors should be considered. We are already seeing. There are still many unmet needs in the management of pigmentary disorders, and much remains to be done.

References

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6. Yu, H.S., Wu, C.S., Yu, C.L. et al. Helium–neon laser irradiation stimulates migration and proliferation in melanocytes and induces repigmentation in segmental‐type vitiligo. J. Invest. Dermatol.120, 56–64 (2003).

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