Antibodies to thromboplastin in systemic lupus erythematosus: isotype distribution and clinical significance in a series of 92 patients.
We determined the prevalence and relationship with clinical manifestations of antibodies to thromboplastin (aTP) in 92 patients with systemic lupus erythematosus (SLE). Thirty-two (35%) patients had aTP: 13 (14%) were positive for IgG aTP, 13 (14%) for IgM aTP, and 6 (7%) for both. Patients with aTP had an increased incidence of thrombosis (p = 0.01), thrombocytopenia (p < 0.001), hemolytic anemia (p < 0.001), and fetal losses (p = 0.03). When the IgG and IgM aTP isotypes were analysed separately, the IgG aTP were found to be associated with thrombosis (p < 0.001), thrombocytopenia (p < 0.001), and fetal losses (p = 0.02). The IgM aTP were associated with hemolytic anemia (p < 0.001). A correlation was found between the titers of aTP and those of anticardiolipin antibodies, in both IgG (p < 0.01, r = 0.6) and IgM (p < 0.01, r = 0.64) isotypes, and between the titers of IgG aTP and the diluted Russell's viper venom time used to detect the lupus anticoagulant (p < 0.001, r = 0.42). This test is a reliable, reproducible and sensitive assay for the detection of antiphospholipid antibodies, specially in those patients under anticoagulant therapy.
Font
J
J
Systemic Autoimmune Diseases Unit, Hospital Clínic, Barcelona, Catalonia, Spain.
López-Soto
A
A
Cervera
R
R
Casals
F J
FJ
Reverter
J C
JC
Muñoz
F J
FJ
Miret
C
C
Bové
A
A
Ordinas
A
A
Ingelmo
M
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000744:Anemia, Hemolytic, Autoimmune / Q000150:complications; D017153:Antibodies, Anticardiolipin / Q000097:blood; D016736:Antiphospholipid Syndrome / Q000150:complications; D001323:Autoantibodies / Q000097:blood*; D016022:Case-Control Studies; D015331:Cohort Studies; D004797:Enzyme-Linked Immunosorbent Assay / Q000706:statistics & numerical data; D005260:Female; D005313:Fetal Death / Q000150:complications; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007132:Immunoglobulin Isotypes / Q000097:blood*; D007075:Immunoglobulin M / Q000097:blood; D016682:Lupus Coagulation Inhibitor / Q000097:blood; D008180:Lupus Erythematosus, Systemic / Q000150:complications / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011247:Pregnancy; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013921:Thrombocytopenia / Q000150:complications; D013925:Thromboplastin / Q000276:immunology*; D013927:Thrombosis / Q000150:complications
D017153:Antibodies, Anticardiolipin; D001323:Autoantibodies; D007074:Immunoglobulin G; D007132:Immunoglobulin Isotypes; D007075:Immunoglobulin M; D016682:Lupus Coagulation Inhibitor; D013925:Thromboplastin