title: Photodynamic therapy for the treatment of different severity of acne: A systematic review.
abstract: BACKGROUND
  Acne, a disease of pilosebaceous unit, is a common dermatologic disorder affecting about 80%-95% of people in both genders in adulthood. The available treatment options are conventional topical and/or oral medications, which are associated with adverse effects, partial response only, contraindications and reoccurrences. This necessitates the need for the introduction of novel treatment for improving acne lesions.
  
  
  OBJECTIVE
  The aim of writing this review is to provide evidence-based information regarding safety and efficacy of PDT in treating acne lesions.
  
  
  METHODS
  The search term 'Acne and PDT' were entered into a search of the National Library of Medicine's PubMed Database. The search returned a total of 143 sources among which 36 studies pertaining to the use of PDT in acne are included in this review article.
  
  
  RESULTS
  36 clinical trials were selected among which 24 trials were performed to see the effect of PDT in acne whereas 12 trials compared the effect of PDT with light or laser alone therapy. Among 24 trials that used PDT only, 3 were clinical trials with control, 14 were clinical trials without control, 6 were randomized controlled trials (RCT) and 1 was retrospective study. On the basis of results of these trials, it is seen that PDT is safe and effective method of treatment for acne lesions. Studies have shown that PDT can control both inflammatory and non-inflammatory acne lesions and can improve all severity of lesions from mild to severe.
  
  
  CONCLUSIONS
  Photodynamic therapy (PDT) has been extensively studied and found to be effective treatment modality for acne lesions. However, more RCTs are needed to establish standard guidelines regarding concentrations and incubation period of photosensitizers and optimal parameters of light sources. Further studies are needed to guide future research and help dermatologist to choose PDT as an effective treatment modality for treating acne lesions.
authors.affiliation: Institute of Photomedicine, Shanghai Skin Disease Hospital, Tongji University School of Medicine, Shanghai, PR China, PR China.
authors.forename: Uma
authors.initials: U
authors.lastname: Keyal
authors.affiliation: Institute of Photomedicine, Shanghai Skin Disease Hospital, Tongji University School of Medicine, Shanghai, PR China, PR China.
authors.forename: Anil Kumar
authors.initials: AK
authors.lastname: Bhatta
authors.affiliation: Institute of Photomedicine, Shanghai Skin Disease Hospital, Tongji University School of Medicine, Shanghai, PR China, PR China. Electronic address: xlwang2001@aliyun.com.
authors.forename: Xiu Li
authors.initials: XL
authors.lastname: Wang
mesh_terms: D000152:Acne Vulgaris / Q000628:therapy*; D019317:Evidence-Based Medicine; D006801:Humans; D010778:Photochemotherapy / Q000592:standards* / Q000639:trends; D012189:Retrospective Studies; D012720:Severity of Illness Index
keywords: Acne vulgaris; Light source; Photodynamic therapy; Photosensitizing agents