title: Circulating thrombopoietin in systemic sclerosis.
abstract: OBJECTIVE
  To investigate circulating thrombopoietin (TPO) concentrations in systemic sclerosis (SSc).
  
  
  METHODS
  TPO concentrations were measured by ELISA in serum samples of 13 patients (11 female, 2 male) with diffuse SSc, 15 healthy controls (13 female, 2 male), and 15 patients (13 female, 2 male) with rheumatoid arthritis (RA). Thrombocyte counts of patients with SSc and RA and controls were recorded.
  
  
  RESULTS
  Median TPO concentrations were 115 (164) in SSc, 76 (32) in RA, and 62 (34) pg/ml in controls. Median serum TPO concentration in the SSc group was significantly higher than other groups; there was no difference between controls and patients with RA (p<0.001 for both comparisons). Median platelet counts of SSc, RA, and controls were 224+/-58x10(9)/l, 238+/-44x10(9)/l, and 272+/-35x10(9)/l, respectively. There was no correlation between thrombocyte counts and TPO levels in any group.
  
  
  CONCLUSIONS
  We show that patients with SSc have higher serum TPO concentrations compared to healthy controls and patients with RA. It can be hypothesized that TPO mediated release of particular growth factors may participate in the pathogenesis of the fibrotic process of SSc.
authors.affiliation: Department of Internal Medicine, Hacettepe University Medical School, Ankara, Turkey.
authors.forename: I
authors.initials: I
authors.lastname: Ertenli
authors.forename: S
authors.initials: S
authors.lastname: Kiraz
authors.forename: H
authors.initials: H
authors.lastname: Ertürk
authors.forename: I C
authors.initials: IC
authors.lastname: Haznedaroglu
authors.forename: I
authors.initials: I
authors.lastname: Celik
authors.forename: M
authors.initials: M
authors.lastname: Calgüneri
authors.forename: S
authors.initials: S
authors.lastname: Kirazli
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010976:Platelet Count; D012016:Reference Values; D012595:Scleroderma, Systemic / Q000097:blood*; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D013926:Thrombopoietin / Q000032:analysis / Q000097:blood*
chemical_list: D015415:Biomarkers; D013926:Thrombopoietin