Progressive macular hypomelanosis

Progressive macular hypomelanosis is an under-recognized disorder characterized by the presence of numerous ill-defined hypopigmented macules and patches on the trunk of young adults. Although common, particularly in Fitzpatrick skin types IV-VI, this condition is frequently misdiagnosed and treated inadequately with antifungals or topical steroids resulting in patient frustration. The exact pathogenesis of progressive macular hypomelanosis is unknown; however, recent studies suggest hypopigmentation results from decreased melanin formation and altered melanosome distribution in response to Proprionibacterium. While there are no well-established or consistently effective therapies for progressive macular hypomelanosis, our growing understanding of its pathogenesis urges consideration of alternative treatment strategies. Here, we report five patients with progressive macular hypomelanosis who benefitted from topical and systemic antimicrobial therapy and summarize the current clinical, pathological and treatment paradigms of this disorder.