Successful Treatment of Extensive Vitiligo with Monobenzone

Vitiligo is one of the most common dermatological disorders, appearing as one or more white macules or patches and affecting up to two percent of the population worldwide. The undesirable aesthetic properties of vitiligo, especially facial, may result in significant negative psychosocial effects, particularly a rate of depression twice that of the general population. While there is no cure, there are several treatment options, notably depigmentation in severe cases. Monobenzone is the most potent depigmenting agent. However, its use is limited due to the permanent and potent nature of the drug. This case presents an example of when timely and aggressive treatment with monobenzone is warranted, demonstrating excellent clinical response, which resulted in a significant increase in the quality of life in a patient with severe vitiligo.Vitiligo is among one of the most common dermatological disorders, affecting up to two percent of the population worldwide.1,2 A chronic and usually progressive disorder, vitiligo presents discretely before 20 years of age, although first presentation in later life may occur as well.2 Clinically, it appears as one or more well-circumscribed, hypopigmented, white macules or patches. This is due to the acquired autoimmune destruction of melanocytes, most often in areas of greater pigmentation, such as the face and dorsum of the hands where they are most exposed to UV radiation.2 Apart from the cosmetic appearance, it is usually asymptomatic, although there is a greater tendency for sunburns and pruritis.2The undesirable aesthetic properties of vitiligo, especially facial, may result in significant negative psychosocial effects, notably a rate of depression twice that of the general population.3 In some cultures, vitiligo is not well understood. The depigmentation of vitiligo is thought to result from sexually transmitted infections, or of leprosy, and can have a damaging effect on educational, social, and employment opportunities.1,2,4 Patients may feel embarrassed or ashamed of such a visible disorder. Studies have shown that vitiligo is associated with a greater burden of disease to patients, especially those in populations with dark skin.1,2,4 Therefore, treatment, although not medically necessary, provides large psychosocial gains for the patient, increasing their quality of life.There is no cure for vitiligo. Current treatment for vitiligo attempts to either increase or decrease pigmentation in order to achieve cosmetically pleasing results and increase the patient''s self-esteem.5 Repigmentation tends to require a prolonged treatment course and yield minimal positive results.6 Strong topical steroids are generally the first line of treatment, with only a 50- to 75-percent repigmentation rate.5,6 Tactrolimus, an immunosuppressive, and calcipotriene, a vitamin D analogue, are alternative topical repigmenting agents, with a similar efficacy as the topical steroids.6 When such treatment fails, psoralen plus ultraviolet A radiation (PUVA) and narrow-band ultraviolet B radiation (NB-UVB) are effective alternatives.5,6 However, PUVA can be carcinogenic and NB-UVB has low efficacy; both require prolonged treatments.6,7 Alternative treatments exist, such as melanocyte transplantations. However, despite the type of treatment, repigmentation still remains difficult and time consuming, especially with advanced vitiligo.Due to the difficulties with repigmentation, it is often easier to achieve depigmentation, especially when vitiligo affects more than 50 percent of the body.5–7 It is, however, a more aggressive approach and its use is considered on an individual basis because of the irreversible changes and increased sensitivity to sunburn of the treated areas. Several treatment modalities exist. Phenols, lasers, cryotherapy, and depigmenting systemic agents, such as imatinib, imiquimod, and diphencyprone, are often considered.7 Monobenzone (monobenzyl ether of hydroquinone, MBEH) is usually the treatment of choice of depigmentation therapy for severe cases of vitiligo, and MBEH is usually used in concentrations of 20 to 40 percent to achieve the desired permanent depigmentation.5,7 It achieves its effects by inducing the necrotic death of melanocytes.7 Topical all-trans-retinoic acid (RA), a vitamin A derivative, causes mild depigmentation and when used in combination with MBEH, has synergistic effects, yielding depigmentation in a short amount of time.7 Nair et al8 have proposed that the RA enhances the absorption of monobenzone by melanocytes through the inactivation of their glutathione-dependent defense mechanisms.7,8 Side effects of MBEH include skin irritation, contact dermatitis, ocular side effects, exogenous ochronosis, and difficulties in predicting response.5,9–11 There can be repigmentation because of sun exposure or rarely as a reaction to the drug.5,7,10,11 Due to these side effects, MBEH treatment can be somewhat controversial, and its use has been limited in some countries, such as the Netherlands, which has restricted it since 1990.7 MBEH has been approved by the United States Food and Drug Administration since 1952 for permanent depigmentation of extensive vitiligo.