THROMBOSIS RESEARCH 67; 601-606,1992 00493848/92 $5.00 + .OO Printed in the USA. Copyright (c) 1992 Pergamon Press Ltd. All rights reserved.
BRIEF ANTICARDIOLIPIN
Yves GRUEL’,
COMMUNICATION
ANTIBODIES IN HEPARIN-ASSOCIATED THROMBOCYTOPENIA
Alain RUPIN112, Herv6 WATIERZ,
Sandrine
VIGIERZ,
Pierre BARDOS2 and Jean LEROY1 1 Laboratoire
(Received
d’Hkmatologie, 2Laboratoire d’lmmunologie, Mbdecine, 37044 Tours Cedex, France.
11.51992;
accepted
in revised form 14.7.1992
Facultk
de
by Editor E. Angles Cano)
INTRODUCTION The antiphospholipid syndrome has been defined by the presence of antiphospholipid antibodies associated with thrombosis and/or thrombocytopenia (1). Heparin-associated thrombocytopenia (HAT) is another immune disorder related to heparin-dependent antibodies but also complicated in about 65 % of cases by arterial and/or venous thrombosis (2). Therefore, it was recently suggested that anticardiolipin antibodies might also be detected in HAT (3). In order to investigate this hypothesis, we looked for anticardiolipin antibodies (ACA) in a group of patients who had developed heparin-associated thrombocytopenia. MATERIAL AND METHODS Twenty-seven patients (13 females and 14 males, age range = 59-90) were All had a normal platelet count before heparin studied. administration for the prevention of postoperative thromboembolic disease (n = 16 with prosthetic surgery in 6 cases) or the treatment of deep vein thrombosis (n = 10) or myocardial infarction (n = 1). After 5 to 20 days of unfractionated heparin therapy, all patients exhibited a platelet In each case, the lower than 100.109/L. consistently count thrombocytopenia resolved within five days following discontinuation of ___-___-_-___-_-___-_~~~_-~~---_ Key Words: Anticardiolipin antibodies, Heparin, Thrombocytopenia 601
602
ANTICARDIOLIPIN
AND HEPARIN
Vol. 67, No. 5
unfractionated heparin and other causes (e.g. infection, other drugs) were excluded. Thrombotic complications were present in 16 cases with either previous venous thromboembolic disease (n = 6) or an aggravation of recent arterial thrombosis (n = 10). In 26 patients, heparin-induced aggregation tests performed as previously described (4), were found to be positive with the platelets from at least one normal donor. Samples for ACA assays in these patients were collected within12 to 72 hours after heparin discontinuation. We also studied 36 hospitalized patients with a normal platelet count (age range = 50-87) and receiving unfractionated heparin for 5 to 15 days either for cardiovascular surgery (coronary artery bypass graft or valvular prosthesis, n = 25) or an ischemic heart disease (n = 11). In this latter had a recent thrombotic event (5 acute myocardial group, 6 cases infarction and 1 deep vein thrombosis). In addition, ACA IgG and IgM were assayed both before and after 5 and10 days of heparin treatment. All samples (serum or plasma) were collected into vacutainer tubes, centrifuged (1,200 g, 15 mins), separated and kept frozen at -30°C until assays. Anticardiolipin antibodies of isotype IgG (ACA IgG) or IgM (ACA IgM) were assayed using a recently reported ELISA method (5). Results were expressed in GPL (ACA IgG) or MPL units (ACA IgM) after establishing standard curves using reference samples containing well-defined amounts of ACA. Finally and in order to seek for a crossreactivity of heparin-dependent antibodies with the cardiolipin molecules, all patients with HAT and found to have significant levels of ACA IgG or IgM were also tested after coincubation of samples with 5 different concentrations of unfractionated heparin, ie 0.25, 0.50, 0.75, 1 or 5 III/ml (6). RESULTS As shown in figure 1, seven patients with HAT exhibited significant levels of ACA IgG (Mean = 19.5, range = 7.5-72 GPL). In addition, two other cases having developed recent arterial thrombosis had high levels of ACA IgM (12.5 and 48.5 MPL). Among the 36 patients receiving heparin but without thrombocytopenia, 2 cases had, after 10 days of anticoagulation for an ischemic heart disease, significant levels of ACA IgG (7 and 30 GPL). Actually, one of these cases (with 30 GPL) had already and before the heparin treatment an ACA level of 45 GPL. On the other hand, 6 additional cases under heparinization and belonging to the group of patients having a cardiac surgery, had also a significant amount of ACA IgM (Mean = 17, range = 8-43 MPL) . For all patients having both heparin-associated thrombocytopenia and ACA, no significant modification of the anticardiolipin reactivity could be
Vol. 67, No. 5
ANTICARDIOLIPIN
AND HEPARIN
IgG
603
IgM
GPILr > 4(1
0 0 0
40
40
30
30
0
20
20
0 0
0
10
8
:
000 0
0
10
0
BRIEF ANTICARDIOLIPIN
Yves GRUEL’,
COMMUNICATION
ANTIBODIES IN HEPARIN-ASSOCIATED THROMBOCYTOPENIA
Alain RUPIN112, Herv6 WATIERZ,
Sandrine
VIGIERZ,
Pierre BARDOS2 and Jean LEROY1 1 Laboratoire
(Received
d’Hkmatologie, 2Laboratoire d’lmmunologie, Mbdecine, 37044 Tours Cedex, France.
11.51992;
accepted
in revised form 14.7.1992
Facultk
de
by Editor E. Angles Cano)
INTRODUCTION The antiphospholipid syndrome has been defined by the presence of antiphospholipid antibodies associated with thrombosis and/or thrombocytopenia (1). Heparin-associated thrombocytopenia (HAT) is another immune disorder related to heparin-dependent antibodies but also complicated in about 65 % of cases by arterial and/or venous thrombosis (2). Therefore, it was recently suggested that anticardiolipin antibodies might also be detected in HAT (3). In order to investigate this hypothesis, we looked for anticardiolipin antibodies (ACA) in a group of patients who had developed heparin-associated thrombocytopenia. MATERIAL AND METHODS Twenty-seven patients (13 females and 14 males, age range = 59-90) were All had a normal platelet count before heparin studied. administration for the prevention of postoperative thromboembolic disease (n = 16 with prosthetic surgery in 6 cases) or the treatment of deep vein thrombosis (n = 10) or myocardial infarction (n = 1). After 5 to 20 days of unfractionated heparin therapy, all patients exhibited a platelet In each case, the lower than 100.109/L. consistently count thrombocytopenia resolved within five days following discontinuation of ___-___-_-___-_-___-_~~~_-~~---_ Key Words: Anticardiolipin antibodies, Heparin, Thrombocytopenia 601
602
ANTICARDIOLIPIN
AND HEPARIN
Vol. 67, No. 5
unfractionated heparin and other causes (e.g. infection, other drugs) were excluded. Thrombotic complications were present in 16 cases with either previous venous thromboembolic disease (n = 6) or an aggravation of recent arterial thrombosis (n = 10). In 26 patients, heparin-induced aggregation tests performed as previously described (4), were found to be positive with the platelets from at least one normal donor. Samples for ACA assays in these patients were collected within12 to 72 hours after heparin discontinuation. We also studied 36 hospitalized patients with a normal platelet count (age range = 50-87) and receiving unfractionated heparin for 5 to 15 days either for cardiovascular surgery (coronary artery bypass graft or valvular prosthesis, n = 25) or an ischemic heart disease (n = 11). In this latter had a recent thrombotic event (5 acute myocardial group, 6 cases infarction and 1 deep vein thrombosis). In addition, ACA IgG and IgM were assayed both before and after 5 and10 days of heparin treatment. All samples (serum or plasma) were collected into vacutainer tubes, centrifuged (1,200 g, 15 mins), separated and kept frozen at -30°C until assays. Anticardiolipin antibodies of isotype IgG (ACA IgG) or IgM (ACA IgM) were assayed using a recently reported ELISA method (5). Results were expressed in GPL (ACA IgG) or MPL units (ACA IgM) after establishing standard curves using reference samples containing well-defined amounts of ACA. Finally and in order to seek for a crossreactivity of heparin-dependent antibodies with the cardiolipin molecules, all patients with HAT and found to have significant levels of ACA IgG or IgM were also tested after coincubation of samples with 5 different concentrations of unfractionated heparin, ie 0.25, 0.50, 0.75, 1 or 5 III/ml (6). RESULTS As shown in figure 1, seven patients with HAT exhibited significant levels of ACA IgG (Mean = 19.5, range = 7.5-72 GPL). In addition, two other cases having developed recent arterial thrombosis had high levels of ACA IgM (12.5 and 48.5 MPL). Among the 36 patients receiving heparin but without thrombocytopenia, 2 cases had, after 10 days of anticoagulation for an ischemic heart disease, significant levels of ACA IgG (7 and 30 GPL). Actually, one of these cases (with 30 GPL) had already and before the heparin treatment an ACA level of 45 GPL. On the other hand, 6 additional cases under heparinization and belonging to the group of patients having a cardiac surgery, had also a significant amount of ACA IgM (Mean = 17, range = 8-43 MPL) . For all patients having both heparin-associated thrombocytopenia and ACA, no significant modification of the anticardiolipin reactivity could be
Vol. 67, No. 5
ANTICARDIOLIPIN
AND HEPARIN
IgG
603
IgM
GPILr > 4(1
0 0 0
40
40
30
30
0
20
20
0 0
0
10
8
:
000 0
0
10
0
