Treatment of progressive macular hypomelanosis with narrow‐band ultraviolet B phototherapy

Treatment for progressive macular hypomelanosis (PMH) has been disappointing. Recently, Propionibacterium acnes had been postulated as the causative agent and narrow‐band ultraviolet B (NBUVB) had been shown to stimulate melanogenesis and has antibacterial properties. The aim of this study was to evaluate the effectiveness of NBUVB in the treatment of PMH. A retrospective analysis of PMH cases diagnosed and treated with NBUVB treatment from 1 January 2007 to 30 April 2009 at the National Skin Centre (NSC) was conducted. The diagnosis of PMH was clinical. Treatment with NBUVB (311 nm) was given twice to thrice weekly. The initial treatment dose was determined as 70% of the patients' individual 311 nm UVB minimal erythema dose. The dose was increased by 10–20% if previous treatment had caused no or slight erythema. Percentage repigmentation from baseline was assessed at each follow‐up. A total of six patients diagnosed with PMH were treated with NBUVB in NSC in the past 2 years. Three patients had good improvement and the remainder had moderate improvement. Recurrence did occur. No adverse events were documented. The success of NBUVB as a monotherapy provides a viable and relatively safe, albeit temporary relief, for these individuals.