title: High frequency ultrasound of skin involvement in systemic sclerosis - a follow-up study.
abstract: BACKGROUND
  High-frequency ultrasound offers a potential for objective and quantitative assessment of skin thickness and skin echogenicity in systemic sclerosis (SSc). Few studies have however assessed the longitudinal changes of skin involvement using ultrasound. The aim of the study was to investigate changes in skin thickness in early SSc using high frequency ultrasound during one year of follow-up in comparison to other measurements of skin fibrosis.
  
  
  METHODS
  This retrospective study comprised 75 consecutive patients with disease duration shorter than 3 years, in whom ultrasound examination of skin thickness was performed at baseline and at the one year follow-up at five predefined sites.
  
  
  RESULTS
  Repeated ultrasound examination identified significant changes in a majority of patients. In 21 patients, the total sum of skin thickness (TST) increased, while TST decreased in 37 patients. On a group level there were significant decreases in skin thickness of the chest (p = 0.024) and in the TST (p = 0.011) during the observation time. Both baseline and follow-up TST correlated to serum-COMP (rS: 0.41; p = 0.001; rS: 0.49; p < 0.001), modified Rodnan skin score (mRSS; rS: 0.48; p < 0.001; rS: 0.48; p < 0.001) and hand mobility in scleroderma (HAMIS; rS: 0.30; p = 0.043; rS: 0.64; p < 0.001). Changes in TST correlated with changes in serum-COMP (rS: 0.30; p = 0.034), changes in mRSS (rS: 0.43; p < 0.001) and changes in HAMIS (rS: 0.53; p = 0.001) during follow-up.
  
  
  CONCLUSIONS
  In early SSc, skin thickness measured by high frequency ultrasound develops in parallel with serum-COMP, mRSS and the HAMIS test. Ultrasound examination of the skin allows for objective assessment of one facet of the complex process of skin fibrosis in early SSc.
authors.affiliation: Department of Clinical Sciences, Section of Rheumatology, Lund University, Lund, Sweden. roger.hesselstrand@med.lu.se.
authors.forename: Roger
authors.initials: R
authors.lastname: Hesselstrand
authors.affiliation: Department of Clinical Sciences, Section of Rheumatology, Lund University, Lund, Sweden. johannacarlestam@hotmail.com.
authors.forename: Johanna
authors.initials: J
authors.lastname: Carlestam
authors.affiliation: Department of Clinical Sciences, Section of Rheumatology, Lund University, Lund, Sweden. marie.wildt@med.lu.se.
authors.forename: Marie
authors.initials: M
authors.lastname: Wildt
authors.affiliation: Department of Clinical Sciences, Section of Rheumatology, Lund University, Lund, Sweden. gunnel.sandqvist@med.lu.se.
authors.forename: Gunnel
authors.initials: G
authors.lastname: Sandqvist
authors.affiliation: Department of Clinical Sciences, Section of Rheumatology, Lund University, Lund, Sweden. kristofer.andreasson@med.lu.se.
authors.forename: Kristofer
authors.initials: K
authors.lastname: Andréasson
mesh_terms: D000328:Adult; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D019220:High-Energy Shock Waves; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012595:Scleroderma, Systemic / Q000000981:diagnostic imaging*; D012867:Skin / Q000000981:diagnostic imaging*; D014463:Ultrasonography