Amelia Ruffatti

Clinical course of high‐risk patients diagnosed with antiphospholipid syndrome

See also Galli M. The antiphospholipid triangle. This issue, pp 234–6.

Incidence of a first thromboembolic event in asymptomatic carriers of high-risk antiphospholipid antibody profile: a multicenter prospective study

Persistent antiphospholipid (aPL) antibodies are occasionally found in subjects without prior history of thromboembolic events (TEs), raising the dilemma of whether to initiate or not a primary thromboprophylaxis. A first TE is considered rare in aPL carriers, but previous studies did not consider the aPL profile nor was the test positivity confirmed in a reference laboratory. In this study, 104 subjects with high-risk aPL profile (positive lupus anticoagulant, anticardiolipin, and anti-β(2)-glycoprotein I antibodies, triple positivity) confirmed in a reference laboratory, were followed up for a mean of 4.5 years. There were 25 first TEs (5.3% per year): the cumulative incidence after 10 years was 37.1% (95% confidence interval [CI], 19.9%-54.3%). On multivariate analysis, male sex (hazard ratio = 4.4; 95% CI, 1.5-13.1, P = .007) and risk factors for venous thromboembolism (hazard ratio = 3.3; 95% CI, 1.3-8.5, P = .01) were independent predictors for TEs. Aspirin did not significantly affect the incidence of TE. In conclusion, the occurrence of a first TE in carriers of high-risk aPL profile is considerable; it is more frequent among male subjects and in the presence of additional risk factors for venous TE. These data can help in the decision to initiate primary thromboprophylaxis in these subjects.

The association between circulating antibodies against domain I of beta2-glycoprotein I and thrombosis: an international multicenter study

Summary.  Background: Diagnosis of the antiphospholipid syndrome (APS) is difficult as a result of limited specificity of existing assays for detecting clinically relevant antiphospholipid antibodies. Anti‐beta2‐glycoprotein I (beta2GPI) antibodies play a central role in the disease process of APS. Objectives: We have investigated the relation between antiphospholipid antibodies with specificity for domain I of beta2GPI and thrombosis/pregnancy morbidity in an international multicenter study. Patients/methods: Four hundred and seventy‐seven patients derived from nine different centres met the inclusion criterion of having anti‐beta2GPI antibodies in their plasma/serum. Clinical data and results of tests for lupus anticoagulant, anti‐cardiolipin antibodies and anti‐beta2GPI antibodies were established at the different centres of inclusion. After being re‐tested for the presence of IgG and/or IgM anti‐beta2GPI antibodies, the samples were tested for the presence of IgG‐directed against domain I of beta2GPI and results were correlated with the thrombotic and obstetric history. Results: Re‐testing for the presence of anti‐beta2GPI antibodies resulted in inclusion of 442/477 patients. IgG class anti‐domain I antibodies were present in plasma of 243/442 patients (55%). 201/243 (83%) had a history of thrombosis. This resulted in an odds ratio of 3.5 (2.3–5.4, 95% confidence interval) for thrombosis. Anti‐domain I IgG antibodies were also significantly correlated with obstetric complications [odds ratio: 2.4 (1.4–4.3, 95% confidence interval)]. Conclusion: In this multicenter study, the detection of IgG antibodies that are directed against domain I of beta2GPI proved to be more strongly associated with thrombosis and obstetric complications than those detected using the standard anti‐beta2GPI antibody assay.

Risk factors for pregnancy failure in patients with anti-phospholipid syndrome treated with conventional therapies: a multicentre, case–control study

OBJECTIVE To identify the risk factors associated with pregnancy failure in patients with APS treated with conventional therapy. METHODS A multicentre, case-control study was conducted to compare APS patients with successful and unsuccessful pregnancy outcomes. We retrospectively considered 410 pregnancies of women diagnosed with primary APS. The study focused on 57 unsuccessful pregnancies (considered the study population) and 57 successful pregnancies (considered the control population) matched for age and therapy. All the patients had been treated with conventional protocol treatments including low-dose aspirin and/or heparin. The clinical and laboratory features of the two groups of women diagnosed with APS were compared. RESULTS The independent risk factors for pregnancy failure were: (i) the presence of SLE or other autoimmune diseases [odds ratio (OR) 6.0; 95% CI 1.7, 20.8; P = 0.01]; (ii) history of both thrombosis and pregnancy morbidity (OR 12.1; 95% CI 1.3, 115.3; P = 0.03); and (iii) triple [Immunoglobulin (Ig) G/IgM aCLs plus IgG/IgM anti-β(2) glycoprotein I antibodies plus LA] aPL positivity (OR 4.1; 95% CI 1.0, 16.7; P = 0.05). APS patients diagnosed on the basis of a single positive test and/or history of pregnancy morbidity alone were generally found to have successful pregnancies. CONCLUSION It would seem from these findings that the risk of pregnancy failure in APS women planning to conceive can be stratified on the basis of some specific clinical and laboratory features.

Failure of intravenous immunoglobulin to prevent congenital heart block: Findings of a multicenter, prospective, observational study

OBJECTIVE Congenital heart block (CHB) is presumed to be caused by transplacental passage of maternal immunoglobulin against Ro and La ribonucleoproteins. The recurrence rate in subsequent pregnancies following the birth of a child with CHB is approximately 19%. The purpose of this study was to determine whether intravenous immunoglobulin (IVIG) therapy could prevent the development of CHB in the fetuses of high-risk pregnant women. METHODS A total of 24 pregnancies in 22 women who had a previous pregnancy in which CHB developed, were over the age of 18 years, were <12 weeks pregnant, and had anti-Ro, anti-La, or both antibodies were monitored in this multicenter, prospective, observational study. Fifteen patients received infusions of IVIG. The 9 pregnancies in the remaining 7 patients served as controls. IVIG was administered at a dose of 400 mg/kg at weeks 12, 15, 18, 21, and 24 of pregnancy. Echocardiograms were performed at least every 3 weeks from week 15 to week 30 of gestation. Electrocardiograms were obtained at birth. The outcome measure was the development of third-degree CHB detected by fetal echocardiogram. RESULTS CHB developed in 3 babies among the 15 pregnancies in the treatment group (20%) and in 1 baby among the 9 pregnancies in the control group (11%). CHB was detected at weeks 18, 23, and 26, respectively, in the 3 babies in the treated group and at week 19 in the baby in the control group. Three of the affected pregnancies ended in termination; 2 for reasons related to the fetal disease and 1 for reasons related to both maternal (severe pulmonary hypertension) and fetal disease (at 21 weeks of gestation). CONCLUSION IVIG at the dose and frequency used in this study was not effective as prophylactic therapy for CHB in high-risk mothers.

Antibody profile and clinical course in primary antiphospholipid syndrome with pregnancy morbidity

In women diagnosed as having category I primary obstetric antiphospholipid syndrome, clinical characteristics and the risk of subsequent thromboembolic events and further unsuccessful pregnancy has not been clearly documented. Women with unexplained obstetric complications and no definite autoimmune systemic diseases were tested for lupus anticoagulant (LA), IgG/IgM anticardiolipin (aCL) and IgG/IgM anti-human beta2-Glycoprotein I (abeta2GPI) antibodies and diagnosed as having primary antiphospholipid syndrome (APS) in classification category I on the basis of more than one laboratory criteria present in any combination. Characteristics at the time of diagnosis and risk factors for subsequent clinical events during a mean follow-up of 6.3 years were evaluated. Fifty-three of 600 women studied were found to fulfil obstetric criteria and had more than one positive laboratory test at the time of diagnosis. All the women were aCL and abeta2GPI positive, and 16 were also LA positive. This latter group (triple positivity) had distinct features and had more frequently experienced previous thromboembolism (OR = 122.5, 95% CI 16-957, p < 0.001). They also had an increased rate of late pregnancy loss (OR = 16.2, 95%CI 0.9-292, p = 0.01), and a higher IgG abeta2GPI titer at diagnosis (median, 25(th) and 75(th) percentile were 118, 37-962, vs. 23, 18-32, respectively, p < 0.0001). During follow-up, the rate of thromboembolic events was significantly higher in the group of women with triple positivity and/ or previous thromboembolism (OR = 57.5, 95% CI 2.7-1160, p = 0.0004) which were the only independent predictors of TE in the multivariate model. Recurrent pregnancy loss took place in seven out of 47 women who had a new pregnancy. Triple positivity and/or previous thromboembolism were again the only independent markers (OR = 34.4, 95% CI 3.5-335.1, p = 0.003) of an unsuccessful new pregnancy. In conclusion, in primary APS with pregnancy morbidity in classification category I, quite different groups of patients may be identified on the basis of laboratory tests. Triple positivity and/or a history of thromboembolism predict new TE events and new unsuccessful pregnancies.

Risk factors for a first thrombotic event in antiphospholipid antibody carriers: a prospective multicentre follow-up study

Objectives To assess risk factors for a first thrombotic event in confirmed antiphospholipid (aPL) antibody carriers and to evaluate the efficacy of prophylactic treatments. Methods Inclusion criteria were age 18–65 years, no history of thrombosis and two consecutive positive aPL results. Demographic, laboratory and clinical parameters were collected at enrolment, once a year during the follow-up and at the time of the thrombotic event, whenever that occurred. Results 258 subjects were prospectively observed between October 2004 and October 2008. The mean±SD follow-up was 35.0±11.9 months (range 1–48). A first thrombotic event (9 venous, 4 arterial and 1 transient ischaemic attack) occurred in 14 subjects (5.4%, annual incidence rate 1.86%). Hypertension and lupus anticoagulant (LA) were significantly predictive of thrombosis (both at p<0.05) and thromboprophylaxis was significantly protective during high-risk periods (p<0.05) according to univariate analysis. Hypertension and LA were identified by multivariate logistic regression analysis as independent risk factors for thrombosis (HR 3.8, 95% CI 1.3 to 11.1, p<0.05, and HR 3.9, 95% CI 1.1 to 14, p<0.05, respectively). Conclusions Hypertension and LA are independent risk factors for thrombosis in aPL carriers. Thromboprophylaxis in these subjects should probably be limited to high-risk situations.

Influence of different IgG anticardiolipin antibody cut‐off values on antiphospholipid syndrome classification

Summary.  Background: While medium to high titers of anticardiolipin (aCL) antibodies, defined as >40 GPL units or >99th percentile, is a laboratory criteria for the ‘definite’ diagnosis of antiphospholipid syndrome (APS), agreement between the two cut‐offs has not been validated. Objective: To validate the current aCL laboratory criterion by verifying the effect of the two cut‐offs on APS classification. Patients/methods: Ninety aCL positive APS patients were selected on the basis of their GPL values above the 99th percentile (17.4 GPL), which was calculated by testing 100 age‐ and sex‐matched healthy subjects. Results: A significant difference in the IgG positivity (P < 0.0001) was found between the APS laboratory profiles as 20 out of the 24 (83.3%) patients with single positivity (aCL alone), six out of the 23 (26.1%) with double positivity (aCL plus lupus anticoagulant or anti‐β2glycoprotein I), and none out of the 43 with triple positivity (aCL plus lupus anticoagulant and anti‐β2glycoprotein I) had titers between the 99th percentile and 40 GPL units. Moreover, the rate of aCL values between the 99th percentile and 40 GPL units was significantly higher (P < 0.0001) in patients with pregnancy morbidity (73.7%) as compared to those with vascular thrombosis (16.9%) and those with both conditions (16.7%). Conclusion: The 99th percentile cut‐off level seems more sensitive than the >40 GPL value for APS classification, as it includes subjects with aCL positivity alone as well as patients with pregnancy morbidity.

Laboratory classification categories and pregnancy outcome in patients with primary antiphospholipid syndrome prescribed antithrombotic therapy.

BACKGROUND A relationship between antibody profile and pregnancy outcome in patients with a previous diagnosis of primary antiphospholipid syndrome (APS) has not been clearly documented. METHODS Women attending our Center with primary APS characterized by the presence in the blood of one or more of the following: Lupus Anticoagulant (LA), IgG/IgM anticardiolipin (aCL), IgG/IgM anti-human beta2-Glycoprotein I (abeta2GPI) antibodies (confirmed after a minimum of 3 months) were considered eligible for this study. Women who became pregnant during the study period with the exception of those with congenital thrombophilia or other congenital abnormalities were included in our analysis. Primary outcome events, defined as early abortion or fetal death, were evaluated in relation to the laboratory classification category assigned to each patient at the time they were diagnosed with APS. RESULTS A total of 97 pregnancies occurring in 79 primary APS patients during the study period were analyzed. Twelve out of 97 pregnancies were unsuccessful, 11 out of 65 (16.9%) in category I patients (more than one positive laboratory test) and 1 out of 32 (3.1%) in category II patients (single positive test; adjusted hazard ratio 1.9; 95% CI, 0.2 to 18.9, p=0.6). Pregnancy loss took place in 10 out of 19 pregnancies (52.6%) in women belonging to category I with triple positivity and in 1 out of 46 pregnancies (2.2%) in patients with double positivity. The rate of pregnancy loss was more frequent in the 19 pregnancies of patients with triple positivity than in the 46 pregnancies of double positive patients (adjusted hazard ratio 23, 95% CI, 1.3 to 408, p=0.03). CONCLUSION Poor pregnancy outcomes occur more frequently in category I than in category II primary APS patients. However, it has been seen that a greater predictability is achieved when category I patients are grouped into triple and double positivity states.

Laboratory and clinical features of pregnant women with antiphospholipid syndrome and neonatal outcome

To evaluate the relationship between the antiphospholipid profile and clinical characteristics of pregnant women with antiphospholipid syndrome (APS) and neonatal outcome.