title: Role of anti-annexin A5 in pathogenesis of hypercoagulable state in patients with antiphospholipid syndrome.
abstract: OBJECTIVE
  Despite several attempts made during the last decade, the exact pathogenesis of exceedingly high thrombotic events and bad obstetric outcome in antiphospholipid syndrome (APS) remains elusive. Anti-annexin A5 (aANX IgG) is thought to have a role in pathophysiology of APS. We studied role of aANX IgG in the pathogenesis of hypercoagulable state in APS patients.
  
  
  METHODS
  We estimated levels of aANX IgG in 112 patients with APS (86 primary and 26 secondary). We also estimated aANX IgG levels in 40 age- and sex-matched healthy controls, 10 patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) each, without any history of thrombosis or pregnancy morbidity, 10 patients of non-APS thrombosis and 10 patients of pregnancy loss without APS.
  
  
  RESULTS
  Only three healthy controls, two SLE (P = 0.239), one RA patient (P = 0.794), three non-APS thrombosis patients (P = 0.086) and two patients with pregnancy loss without APS (P = 0.258) had marginally elevated values, whereas 53 primary APS (P < 0.001) and 16 secondary APS (P < 0.001) were positive. We also compared aANX IgG levels in different groups. Mean ± standard errors of the mean of healthy controls was 3.77 ± 0.49, in SLE patients it was 4.88 ± 1.17 (P = 1.000), in RA patients it was 4.67 ± 0.97 (P = 1.000), in non-APS thrombosis it was 7.93 ± 0.88 (P = 0.488) and in pregnancy loss without APS it was 6.80 ± 0.93 (P = 0.789). However, it was significantly elevated in primary APS (12.87 ± 1.07, P < 0.001), secondary APS (11.98 ± 1.41, P = 0.001) and total APS patients (12.68 ± 0.88, P < 0.001).
  
  
  CONCLUSIONS
  From the above observations it appears that aANX IgG plays a significant role in producing a hypercoagulable state in primary and secondary APS.
authors: Department of Medicine, Banaras Hindu University, Varanasi, India. singhnk20@yahoo.co.in
authors: Nand K
authors: NK
authors: Singh
authors: Dawesh Prakash
authors: DP
authors: Yadav
authors: Anurag
authors: A
authors: Gupta
authors: Usha
authors: U
authors: Singh
authors: Manoj
authors: M
authors: Godara
mesh_terms: D000022:Abortion, Spontaneous / Q000097:blood / Q000276:immunology; D000293:Adolescent; D000328:Adult; D017304:Annexin A5 / Q000097:blood / Q000276:immunology*; D016736:Antiphospholipid Syndrome / Q000097:blood / Q000150:complications / Q000175:diagnosis / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood*; D001777:Blood Coagulation; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D011247:Pregnancy; D012307:Risk Factors; D019851:Thrombophilia / Q000097:blood / Q000175:diagnosis / Q000276:immunology*; D055815:Young Adult
chemical_list: D017304:Annexin A5; D001323:Autoantibodies
keywords: anti‐phospholipid antibody syndrome; disease aetiology and pathogenesis; human anti‐phospholipid antibody syndrome