Optimal management of recalcitrant disorders of hyperpigmentation in dark-skinned patients

Abstract

Alterations in skin pigmentation may often have a dramatic expression in individuals with a dark skin complexion and can be a source of significant emotional distress in these individuals. Hyperpigmented disorders such as melanosis (melasma), post-inflammatory hyperpigmentation, drug-induced hyperpigmentation, and erythema dyschromicum perstans tend to have a prolonged course and, in many cases, are refractory to treatment, further contributing to the psychological impairment of the affected patients. Melanosis, is a common form of facial pigmentation attributable to sunlight and hormonal factors. A range of treatment modalities, such as depigmenting agents, topical retinoids, and chemical peels in conjunction with rigorous sun protection, can improve the melanosis but the condition usually recurs. Combination regimens, including frequent applications of superficial- and medium-depth chemical peels, appear to be particularly effective and well tolerated in dark-skinned patients with melanosis. Post-inflammatory hyperpigmentation is the result of excess pigment deposition following an inflammatory skin disorder. Topical tretinoin, hydroquinone, azelaic acid, kojic acid, and glycolic acid peels have been employed with variable degrees of success. Drug-induced pigmentation is a frequent cause of acquired hypermelanosis, its clinical expression depending on the triggering molecule and the underlying pathogenetic mechanism. Identifying and discontinuing the offending agent is the main approach in this condition, although, recent reports have demonstrated the efficacy of Q-switched lasers in accelerating the pigment removal. Erythema dischromicum perstans is a characteristic dermal pigmentation occurring mainly in dark-skinned individuals. Immunomodulating agents, such as clofazimine and dapsone have been shown to lighten this disorder, although, the exact mode of action is not clear.