title: Assessment of blood clot formation and platelet receptor function ex vivo in patients with primary Sjogren's syndrome.
abstract: OBJECTIVE
  Primary Sjögren's syndrome (pSS) shares clinical features and pathogenetic mechanisms with systemic lupus erythematosus (SLE). SLE is associated with an increased thromboembolic risk; however, it is unclear whether pSS patients are susceptible to thromboembolic diseases. In this study, we examined ex vivo blood clot formation (clot strength, rates of clot formation and lysis) in pSS using thromboelastography (TEG) and platelet aggregation to common agonists using multiple electrode aggregometry (MEA). We also investigated the relationship between TEG/MEA parameters and clinical/laboratory features of pSS.
  
  
  METHODS
  Case control.
  
  
  METHODS
  Secondary care, single centre.
  
  
  METHODS
  34 pSS patients, 11 SLE patients and 13 healthy volunteers (all women) entered and completed the study.
  
  
  METHODS
  
  
  
  METHODS
  TEG and MEA parameters between three subject groups.
  
  
  RESULTS
  The relationships between TEG/MEA and clinical/laboratory parameters analysed using bivariate correlation analysis with corrections for multiple testing.
  
  
  RESULTS
  All TEG and MEA parameters were similar for the three subject groups. After corrections for multiple testing, interleukin (IL)-1α and Macrophage inflammatory proteins (MIP)-1α remain correlated inversely with clot strength (r=-0.686, p=0.024 and r=-0.730, p=0.012, respectively) and overall coagulability (r=-0.640, p=0.048 and r=-0.648, p=0.048). Stepwise regression analysis revealed that several cytokines such as MIP-1α, IL-17a, IL-1α and Interferon (IFN)-γ may be key predictors of clot strength and overall coagulability in pSS.
  
  
  CONCLUSIONS
  Clot kinetics and platelet receptor function are normal in pSS. Several cytokines correlate with clot strength and overall coagulability in pSS.
authors.affiliation: Musculoskeletal Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: K S
authors.initials: KS
authors.lastname: Collins
authors.forename: K
authors.initials: K
authors.lastname: Balasubramaniam
authors.forename: G
authors.initials: G
authors.lastname: Viswanathan
authors.forename: A
authors.initials: A
authors.lastname: Natasari
authors.forename: J
authors.initials: J
authors.lastname: Tarn
authors.forename: D
authors.initials: D
authors.lastname: Lendrem
authors.forename: S
authors.initials: S
authors.lastname: Mitchell
authors.forename: A
authors.initials: A
authors.lastname: Zaman
authors.forename: W F
authors.initials: WF
authors.lastname: Ng
keywords: Rheumatology