Antibodies to phosphatidylserine/prothrombin complex as an additional diagnostic marker of APS?
Antiprothrombin antibodies can be measured by ELISA using either a prothrombin/phosphatidylserine complex (aPS/PT) or prothrombin alone (aPT) as antigen. We aimed to compare the clinical features of autoimmune patients with avidity of aPS/PT and determine the diagnostic efficiency of aPS/PT and aPT for assessing antiphospholipid syndrome (APS). aPS/PT were of low (n = 9), heterogeneous (n = 31) and high (n = 8) avidity out of 48 cases. None of the samples with low avidity were positive in aPT ELISA. Among patients with heterogeneous or high avidity aPS/PT, there was a significantly greater number of patients with APS as compared to patients with low avidity (38/39 vs. 7/9; p < 0.05). No SLE patients had high avidity antiprothrombin antibodies.
University Medical Centre, Department of Rheumatology, Immunology laboratory, Ljubljana, Slovenia. polona.zigon@guest.arnes.si
P
P
Žigon
S
S
Čučnik
A
A
Ambrožič
S
S
Sodin Šemrl
T
T
Kveder
B
B
Božič
D000915:Antibody Affinity; D016736:Antiphospholipid Syndrome / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology; D010718:Phosphatidylserines / Q000276:immunology*; D011516:Prothrombin / Q000276:immunology*
D001323:Autoantibodies; D015415:Biomarkers; D010718:Phosphatidylserines; D011516:Prothrombin