Sessa A, Meroni M, Battini G (eds): Systemic Lupus erythematosus: Renal Vasculitis Contrib Nephrol. Basel, Karger, 1992, vol 99, pp 118-122
Lupus Anticoagulants and Antiphospholipid Antibodies Monitoring in Systemic Lupus erythematosus C.C. Arianna, A. Salmeggia, D. Croci, E. Lampertie, P. Botteroe, Α. Castiglione`, E. Venegonib, L. La Mantiaa, M. Eolie °Istituto Neurologico C. Besta, Milano; hispedale G. Fornaroli, Magenta, ed `Ospedale Fatebenefratelh, Milano, Italia
The presence of acquired antiphospholipid (auto)antibodies is a wellknown feature of systemic lupus erythematosus (SLΕ). A significant relationship has been reported [1] between the presence of lupus anticoagulant factor (LAC) activity and anticardiolipin antibodies (ACA) and previous occurrence of venous or arterial thrombotic complications or recurrent fetal losses. No definitive agreement has been reached, however, about the prevalence of LAC or ACA, or about the correlation between serial antiphospholipid antibodies measurement and clinical disease activity and/or steroid treatment. In order to clarify these interrelationships, we have undertaken a prospective study in 15 patients with SLΕ, assessing LAC, ACA, antiphospholipid antibodies (APA) and routine clotting and hematologic assays.
Fifteen patients affected by SLΕ according to the American Rheumatism Association criteria [2] and recruited from the general Hospital of Magenta (Milan) and Fatebenefratelli Hospital (Milan) were studied. Clinical data of the patients are reported in table 1; patients were either untreated (3) or treated with antimalarial drugs (2) or with prednisone (0.1-1 mg/ kg/day) (10). Bimonthly clinical and laboratory analyses were performed: complete blood cell count with platelets, fibrinogen, and AP'AT. Antiphospholipid antibodies were investigated by (a) anticardiolipin antibodies, according to Harris et al. [3]; (b) antiphospholipid antibodies (by a commercially available method: Asserachrom apa Stago); (c) lupus anticoagulant activity was assessed by a new method [4] that was designed with the aim of specifically detecting antiphospholipid antibodies and minimizing the effects of other possible inhibitory factors (heparin, antiprothrombin antibodies, for example).
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Patients and Methods
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Table 1. Clinical data
Patients, n Age, years (range) Sex Disease duration, months (range) Prestudy involvement Renal Joint/cutaneous Sclerositís Hematologic Nervous system Thrombotic (including recurrent fetal losses)
Steroid treatment
Antimalarial treatment
No treatment
10 42 (26-69) 10F 109 (8-300)
2 43 (31-55) 2F 42 (12-72)
3 29 (17-35) 3F 56 (12-120)
5 4 3 6 6 6
0 2 2 0 0 0
1 3 1 1 0 0
Patients' plasma was centrifuged at 1 1,500 g for 10 min before coagulation tests. Different dilutions with normal plasma were studied; the two tests were (a) an APTT with micronized silica and a standard concentration of bovine phospholipids (IL), and (b) a modified APTT (Silica Clotting Time) with a reagent obtained by diluting (1/10) the normal reagent with a phospholipid-free silica suspension (IL). We then performed the following calculation for each dilution point: R (SCT)—R (APTT)/R (APTT) (R = ratio with normal pool) and named the resulting values DIR (Delta Normalized Ratio). Titers and indication of 'LAC activity were given as base 2 logarithms of the dilution with normal pool that normalized the tests.
Anticardiolipin or antiphospholipid antibodies or LAC activity were detected in 11/15 patients (8/10 steroid- and 1/2 antimalarial-treated and 2/3 untreated). However, in some of the patients serial analysis yielded only one or two positive values. The relationship between previous thrombotic events or vascular involvement during follow-up and anticoagulant activity is reported in table 2. Elevated values (excluding borderline points) of LAC were detected in 4/5 patients with and in 6/10 without previous thrombotic complications; 3/5 patients with and 6/10 patients without previous thrombotic complications had high ACA. 3/5 patients with and 3/10 patients without previous thrombotic complications had high APA. However, high ACA were frequently an isolated finding during the follow-up, while elevated APA and LAC activity were more constant in single patients. Considering together LAC, ACA and APA, 6/10 patients without and 5/5
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Results
Ariano et al.
120
Table 2. LAC, ACA, APA, and thrombosis Patient No.
ACA
Previous Thrombosis thrombosis during study
LAC
+ -
+
+
+
0 0 0 0 ++ (6/6) ++ (3/6) ± (2/6) ± (2/6) + (4/6) +++ (7,ι7) + (5/6) + + + (6/6) 0 +++ (6/6) + (3/5) + (6/6) + (1/6) + (3/6) ++± (6/6) + (1/6) + (6/6) ± (1/6) + + + (6/6) + (1 /6) 0 0 + (2/6) +++ (6/7) 0 +++ (6/7)
APA
Sirria] (recOmen!
1
2 3 4 5 6 7 8 9
ιο
Antimalarial treatmeni Il
2 Untreated 13 14 15
+ + -+
+
+
+ (5/7) 0
+ ( /7) 0
0 0
± (2/7) ± (1/6) ++ (4/5)
+ (3/7) + (1/6) ++ (5/5)
± (3/7) ± (1/6) + (5/5)
patients with previous thrombosis had at least 1 abnormal finding during the follow-up. Steroid-treated patients with vascular involvement during follow-up had higher LAC and APA but not significantly higher ACA than steroid-treated patients without vascular involvement during follow-up (table 3). Relationships among LAC, ACA, APA, APTT and steroid dose were investigated by linear regression in all patients: steroid dose was positively correlated with LAC (r = 0.7), APA (r = 0.43) and APTT (r = 0.47), but not with ACA. Analysis of LAC, ACA, APA, fibrinogen and APTT values in steroidtreated versus untreated or antimalarial-treated patients is reported in table 4. Serial analysis in single-steroid-treated patients (fig. 1) showed that the steroid dose was related to LAC; steroid reductions were often followed by increases in LAC. In some cases, this increase preceded disease exacerbation which led to further increase in steroid dose. No relationships were detected between platelet number or WBC count and the various clotting tests analyzed, either in treated or untreated patients (data not shown).
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Symbols: 0, ±. +, + +, + + + corresponded to titers (arbitrary units) of: 3. respectively. Number of abnormal values out of total determinations in parentheses.
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Table 3. LAC, ACA, and ΑPΑ in steroid-treated patients Steroid-treated patients with vascular involvement during study (4) LAC ACA APA
4.3 + 2.9 0.9 ± 1.1 2.6 ± 1.8
p 0.0001 0.06
Lupus Anticoagulants and Antiphospholipid Antibodies Monitoring in Systemic Lupus erythematosus C.C. Arianna, A. Salmeggia, D. Croci, E. Lampertie, P. Botteroe, Α. Castiglione`, E. Venegonib, L. La Mantiaa, M. Eolie °Istituto Neurologico C. Besta, Milano; hispedale G. Fornaroli, Magenta, ed `Ospedale Fatebenefratelh, Milano, Italia
The presence of acquired antiphospholipid (auto)antibodies is a wellknown feature of systemic lupus erythematosus (SLΕ). A significant relationship has been reported [1] between the presence of lupus anticoagulant factor (LAC) activity and anticardiolipin antibodies (ACA) and previous occurrence of venous or arterial thrombotic complications or recurrent fetal losses. No definitive agreement has been reached, however, about the prevalence of LAC or ACA, or about the correlation between serial antiphospholipid antibodies measurement and clinical disease activity and/or steroid treatment. In order to clarify these interrelationships, we have undertaken a prospective study in 15 patients with SLΕ, assessing LAC, ACA, antiphospholipid antibodies (APA) and routine clotting and hematologic assays.
Fifteen patients affected by SLΕ according to the American Rheumatism Association criteria [2] and recruited from the general Hospital of Magenta (Milan) and Fatebenefratelli Hospital (Milan) were studied. Clinical data of the patients are reported in table 1; patients were either untreated (3) or treated with antimalarial drugs (2) or with prednisone (0.1-1 mg/ kg/day) (10). Bimonthly clinical and laboratory analyses were performed: complete blood cell count with platelets, fibrinogen, and AP'AT. Antiphospholipid antibodies were investigated by (a) anticardiolipin antibodies, according to Harris et al. [3]; (b) antiphospholipid antibodies (by a commercially available method: Asserachrom apa Stago); (c) lupus anticoagulant activity was assessed by a new method [4] that was designed with the aim of specifically detecting antiphospholipid antibodies and minimizing the effects of other possible inhibitory factors (heparin, antiprothrombin antibodies, for example).
Downloaded by: National Univ. of Singapore 137.132.123.69 - 3/27/2017 5:27:41 AM
Patients and Methods
Lupus Anticoagulants and Antiphospholipid Antibodies Monitoring in SLE
119
Table 1. Clinical data
Patients, n Age, years (range) Sex Disease duration, months (range) Prestudy involvement Renal Joint/cutaneous Sclerositís Hematologic Nervous system Thrombotic (including recurrent fetal losses)
Steroid treatment
Antimalarial treatment
No treatment
10 42 (26-69) 10F 109 (8-300)
2 43 (31-55) 2F 42 (12-72)
3 29 (17-35) 3F 56 (12-120)
5 4 3 6 6 6
0 2 2 0 0 0
1 3 1 1 0 0
Patients' plasma was centrifuged at 1 1,500 g for 10 min before coagulation tests. Different dilutions with normal plasma were studied; the two tests were (a) an APTT with micronized silica and a standard concentration of bovine phospholipids (IL), and (b) a modified APTT (Silica Clotting Time) with a reagent obtained by diluting (1/10) the normal reagent with a phospholipid-free silica suspension (IL). We then performed the following calculation for each dilution point: R (SCT)—R (APTT)/R (APTT) (R = ratio with normal pool) and named the resulting values DIR (Delta Normalized Ratio). Titers and indication of 'LAC activity were given as base 2 logarithms of the dilution with normal pool that normalized the tests.
Anticardiolipin or antiphospholipid antibodies or LAC activity were detected in 11/15 patients (8/10 steroid- and 1/2 antimalarial-treated and 2/3 untreated). However, in some of the patients serial analysis yielded only one or two positive values. The relationship between previous thrombotic events or vascular involvement during follow-up and anticoagulant activity is reported in table 2. Elevated values (excluding borderline points) of LAC were detected in 4/5 patients with and in 6/10 without previous thrombotic complications; 3/5 patients with and 6/10 patients without previous thrombotic complications had high ACA. 3/5 patients with and 3/10 patients without previous thrombotic complications had high APA. However, high ACA were frequently an isolated finding during the follow-up, while elevated APA and LAC activity were more constant in single patients. Considering together LAC, ACA and APA, 6/10 patients without and 5/5
Downloaded by: National Univ. of Singapore 137.132.123.69 - 3/27/2017 5:27:41 AM
Results
Ariano et al.
120
Table 2. LAC, ACA, APA, and thrombosis Patient No.
ACA
Previous Thrombosis thrombosis during study
LAC
+ -
+
+
+
0 0 0 0 ++ (6/6) ++ (3/6) ± (2/6) ± (2/6) + (4/6) +++ (7,ι7) + (5/6) + + + (6/6) 0 +++ (6/6) + (3/5) + (6/6) + (1/6) + (3/6) ++± (6/6) + (1/6) + (6/6) ± (1/6) + + + (6/6) + (1 /6) 0 0 + (2/6) +++ (6/7) 0 +++ (6/7)
APA
Sirria] (recOmen!
1
2 3 4 5 6 7 8 9
ιο
Antimalarial treatmeni Il
2 Untreated 13 14 15
+ + -+
+
+
+ (5/7) 0
+ ( /7) 0
0 0
± (2/7) ± (1/6) ++ (4/5)
+ (3/7) + (1/6) ++ (5/5)
± (3/7) ± (1/6) + (5/5)
patients with previous thrombosis had at least 1 abnormal finding during the follow-up. Steroid-treated patients with vascular involvement during follow-up had higher LAC and APA but not significantly higher ACA than steroid-treated patients without vascular involvement during follow-up (table 3). Relationships among LAC, ACA, APA, APTT and steroid dose were investigated by linear regression in all patients: steroid dose was positively correlated with LAC (r = 0.7), APA (r = 0.43) and APTT (r = 0.47), but not with ACA. Analysis of LAC, ACA, APA, fibrinogen and APTT values in steroidtreated versus untreated or antimalarial-treated patients is reported in table 4. Serial analysis in single-steroid-treated patients (fig. 1) showed that the steroid dose was related to LAC; steroid reductions were often followed by increases in LAC. In some cases, this increase preceded disease exacerbation which led to further increase in steroid dose. No relationships were detected between platelet number or WBC count and the various clotting tests analyzed, either in treated or untreated patients (data not shown).
Downloaded by: National Univ. of Singapore 137.132.123.69 - 3/27/2017 5:27:41 AM
Symbols: 0, ±. +, + +, + + + corresponded to titers (arbitrary units) of: 3. respectively. Number of abnormal values out of total determinations in parentheses.
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121
Table 3. LAC, ACA, and ΑPΑ in steroid-treated patients Steroid-treated patients with vascular involvement during study (4) LAC ACA APA
4.3 + 2.9 0.9 ± 1.1 2.6 ± 1.8
p 0.0001 0.06
