|
A 50-year-old woman presents for the evaluation and treatment of brown patches on her dorsal forearms. On examination, she has irregularly shaped brown patches on both forearms. She said these have been developing over the past several years. She notices that they seem to get darker with sun exposure. On careful examination, she has similar, very faint brown patches on her bilateral upper cheeks, forehead and glabellar region, and upper lip. I asked her when she first noticed the patches on her face and she said “after my first pregnancy”. Biopsy confirmed the suspected diagnosis.
Diagnosis:
Melasma
Discussion
Sometimes I forget that melasma can occur on other areas of the body including the arms, as is this case. I tell my patients that melasma is a very rapid, uneven suntan. Under the exposure of ultraviolet radiation, sensitized melanocytes will aggressively and rapidly produce melanin. In my experience, sensitization is related to pregnancy and/or exogenous hormones such as birth control pills. I have noticed in a smaller yet significant percentage of patients with birth control pill associated melasma, if they stop the birth control pills, the melasma will improve. Unfortunately, in the majority of cases, even the cessation of oral contraceptives will not produce a significant diminution in melasma activity. I also tell patients that the cells that produce color in our skin (melanocytes) only represent about 2 to 3% of our total skin cells. I explain that they have long arms like an octopus that feed 40+ other skin cells around them with little packets of color. Unfortunately, sometimes patients have melanocytes that reside very deep in the skin and the topical medications that we use including hydroquinone containing products to fade away melanin can’t penetrate that far. I explain that is why melasma is such a difficult condition to treat. As one of my colleagues recently stated at a “skin-of-color” conference, in some of my most difficult melasma cases I don’t think I could get rid of the excess color even with an atom bomb!”
My initial approach is a good explanation with the patient about using a product hydroquinone twice daily (pea-sized) for no more than five months. I use a cream compounded with hydroquinone 6%, kojic acid 3%, tretinoic acid 0.05% and hydrocortisone 0.05%. After 5 months, I always give it a two month break/washout period using an ammonium lactate containing lotion with a kojic acid product to maintain fading activity. This must be coupled with meticulous sun protection, and I tell patients that are very concerned about the condition to use a double sunscreen. I use Vanicream SPF 30 with ultraviolet A protection as a base and I use MelaShade sunscreen on top. MelaShade actually contains melanin derived from marine sources. I instruct them to apply it at least 30 minutes before sun exposure and reapply every 60 minutes, and even more frequently if swimming or perspiring. I also explain that if they use hydroquinone for too long, it actually will block an enzyme and cause the skin to become darker (exogenous ochronosis). If topical hydroquinone products are partially successful and the patient needs additional treatment, I use the Skin Active program by NeoStrata with a series of 12 increasing strength chemical peels done twice monthly for six months. Finally, if that doesn’t work or if patients want to be aggressive initially, I use a system called the Melanage peel system. It contains Arbutin (a.k.a. arbutase, a glycosylated hydroquinone at approximately 14%), Vitamin C, Kojic acid, beta glucosidase and ferulic acid. using 14% hydroquinone. In my experience, the topical prescription strength hydroquinone-containing products work about 60% of the time, the chemical peels work about 70% of the time, and the deep intense Melanage peel works about 80% of the time. I define “works” as the patients report they are happy with the results. Nevertheless, no matter how effective they are, if they are not coupled with meticulous sun protection, the condition will return.
|
