Progressive macular hypomelanosis pathogenesis and treatment: a randomized clinical trial

Abstract

BackgroundProgressive macular hypomelanosis (PMH) is a cosmetically disturbing skin disorder that is poorly understood with indefinite treatment. The aim of the present study was to clinically outline PMH and study its pathogenesis. Based upon the literature suggesting improvement of PMH with antibiotic therapy to decrease Propionibacterium acnes (P. acnes) colonization, different treatment modalities were tried to reach the best treatment option. Patients and methodsThis study included 12 newly diagnosed PMH selected patients who attended Tanta University Hospital outpatient clinic of Dermatology and Venereology from June 2009 to March 2010. Patient's lesions were subjected to wood's lamp and potassium hydroxide (KOH) examination as well as biopsies used in histological, immunohistochemical, bacteriological and electron microscopic examination. A randomized clinical trial with different treatment modalities was applied. ResultsThe patient's mean age was 25±10.8 with significant female predominance (P=0.0001). Reduction of epidermal melanosomes and tyrosine activity together with difference in distribution of S100 proteins in hypopigmented skin was demonstrated. Abnormal distribution of tonofilaments was noticed inside keratinocytes with increased apoptosis. P. acnes were detected in hair follicles of 83.3% hypopigmented lesions. Administration of local and systemic antimicrobial treatment with narrow band ultraviolet B (NBUVB) phototherapy for 3 months was the best treatment modalities. ConclusionThe etiology of PMH is multifactorial where genetic predisposition, the presence of P. acnes and hormonal imbalance play the main role. Administration of local and systemic antimicrobial treatment with NBUVB phototherapy for 3 months is an effective treatment regimen for PMH.