title: Improving acne keloidalis nuchae with targeted ultraviolet B treatment: a prospective, randomized, split-scalp comparison study.
abstract: BACKGROUND
  Acne keloidalis nuchae (AKN) is a chronic scarring folliculitis with fibrotic papules on the occipital scalp. Its treatment is limited and unsatisfactory.
  
  
  OBJECTIVE
  To determine whether targeted ultraviolet B (tUVB) phototherapy will (i) improve the clinical appearance of AKN and (ii) induce extracellular matrix remodelling in affected lesions.
  
  
  METHODS
  Eleven patients with AKN were enrolled in a prospective, randomized, split-scalp comparison study. One randomly selected side of the scalp was treated with tUVB up to three times weekly for 8 weeks. After week 8, both sides were treated for eight additional weeks. Assessment included lesion counts in two 3 × 3-cm regions of interest (ROIs), one on each side of the scalp (ROI-1: tUVB weeks 0-16, ROI-2: tUVB weeks 9-16), patient self-assessment and analysis of MMP1, MMP9, TGFB1 and COL1A1 mRNA expression by quantitative reverse-transcription polymerase chain reaction.
  
  
  RESULTS
  Before treatment, the mean lesion count was similar between tUVB-treated and untreated sides (14·8 vs. 15·0). After 8 weeks of tUVB, the mean lesion count decreased significantly to 9·4 ± 1·2 (P =  0·03), with no change on the untreated side. With continued treatment, the mean lesion count in ROI-1 decreased further to 7 ± 1·5 (P = 0·04) after 16 weeks of tUVB.
  
  
  CONCLUSIONS
  tUVB significantly improved the clinical appearance of AKN, led to patient satisfaction and was well tolerated.
authors.affiliation: Department of Dermatology, Johns Hopkins University School of Medicine, 1550 Orleans Street, Baltimore, MD, 21231, U.S.A.
authors.forename: G A
authors.initials: GA
authors.lastname: Okoye
authors.forename: B M
authors.initials: BM
authors.lastname: Rainer
authors.forename: S G
authors.initials: SG
authors.lastname: Leung
authors.forename: H S
authors.initials: HS
authors.lastname: Suh
authors.forename: J H
authors.initials: JH
authors.lastname: Kim
authors.forename: A M
authors.initials: AM
authors.lastname: Nelson
authors.forename: L A
authors.initials: LA
authors.lastname: Garza
authors.forename: A L
authors.initials: AL
authors.lastname: Chien
authors.forename: S
authors.initials: S
authors.lastname: Kang
mesh_terms: D000153:Acne Keloid / Q000532:radiotherapy*; D000328:Adult; D024042:Collagen Type I / Q000378:metabolism; D000090602:Collagen Type I, alpha 1 Chain; D005260:Female; D006801:Humans; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D008875:Middle Aged; D017060:Patient Satisfaction; D010865:Pilot Projects; D011446:Prospective Studies; D012536:Scalp Dermatoses / Q000532:radiotherapy*; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D016896:Treatment Outcome; D014467:Ultraviolet Therapy / Q000379:methods*
chemical_list: D024042:Collagen Type I; D000090602:Collagen Type I, alpha 1 Chain; C508960:TGFB1 protein, human; D053773:Transforming Growth Factor beta1; C579270:MMP9 protein, human; D020780:Matrix Metalloproteinase 9; C522360:MMP1 protein, human; D020781:Matrix Metalloproteinase 1