Joan Carles Reverter

Clinical study and follow-up of 100 patients withthe antiphospholipid syndrome

Abstract Objectives: To study the clinical characteristics at diagnosis and during follow-upof patients with the antiphospholipid syndrome (APS) and to analyze the influence of treatment on their outcome. Patients: One hundred patients with APS were included (86% female and 14%male; mean age, 36 years). Sixty-two percent had primary APS and 38% had APS associated with systemic lupus erythematosus (SLE). The median length of follow-up was 49 months. Results: Fifty-three percent of the patients had thromboses, 52% had thrombocytopenia, and 60% of the women had pregnancy losses. Patients with APS associated with SLE had a higher prevalence of hemolytic anemia ( P = .02), thrombocytopenia (platelet count lower than 100 × 10 9 /L) ( P = .004), antinuclear antibodies ( P = .0002), and low complement levels. Fifty-three percent of the patients with thrombosis had recurrent episodes (86% in the same site as the previous thrombotic event). Recurrences were observed in 19% of the episodes treated with long-term oral anticoagulation, in 42% treated prophylactically with aspirin, and in 91% in which anticoagulant/antiaggregant treatment was discontinued ( P = .0007). Multivariate analysis showed that prophylactic treatment and older age had an independent predictive value for rethrombosis. Prophylactic treatment during pregnancy (usually with aspirin) increased the live birth rate from 38% to 72% ( P = .0002). Conclusions: Patients with APS have a high risk of recurrent thromboses. Long-term oral anticoagulation seems to be the best prophylactic treatment to prevent recurrences. Prophylactic treatment with aspirin during pregnancy reduced the rate of miscarriages remarkably.

Reversal of apixaban induced alterations in hemostasis by different coagulation factor concentrates: significance of studies in vitro with circulating human blood.

Apixaban is a new oral anticoagulant with a specific inhibitory action on FXa. No information is available on the reversal of the antihemostatic action of apixaban in experimental or clinical settings. We have evaluated the effectiveness of different factor concentrates at reversing modifications of hemostatic mechanisms induced by moderately elevated concentrations of apixaban (200 ng/ml) added in vitro to blood from healthy donors (n = 10). Effects on thrombin generation (TG) and thromboelastometry (TEM) parameters were assessed. Modifications in platelet adhesive, aggregating and procoagulant activities were evaluated in studies with blood circulating through damaged vascular surfaces, at a shear rate of 600 s−1. The potential of prothrombin complex concentrates (PCCs; 50 IU/kg), activated prothrombin complex concentrates (aPCCs; 75 IU/kg), or activated recombinant factor VII (rFVIIa; 270 μg/kg), at reversing the antihemostatic actions of apixaban, were investigated. Apixaban interfered with TG kinetics. Delayed lag phase, prolonged time to peak and reduced peak values, were improved by the different concentrates, though modifications in TG patterns were diversely affected depending on the activating reagents. Apixaban significantly prolonged clotting times (CTs) in TEM studies. Prolongations in CTs were corrected by the different concentrates with variable efficacies (rFVIIa≥aPCC>PCC). Apixaban significantly reduced fibrin and platelet interactions with damaged vascular surfaces in perfusion studies (p<0.05 and p<0.01, respectively). Impairments in fibrin formation were normalized by the different concentrates. Only rFVIIa significantly restored levels of platelet deposition. Alterations in hemostasis induced by apixaban were variably compensated by the different factor concentrates investigated. However, effects of these concentrates were not homogeneous in all the tests, with PCCs showing more efficacy in TG, and rFVIIa being more effective on TEM and perfusion studies. Our results indicate that rFVIIa, PCCs and aPCCs have the potential to restore platelet and fibrin components of the hemostasis previously altered by apixaban.

Prevalence of hepatitis C virus infection in patients with antiphospholipid syndrome

BACKGROUND/AIMS The aim of this study was to determine the prevalence and clinical significance of hepatitis C virus (HCV) infection in patients with the antiphospholipid syndrome (APS). METHODS A series of 88 consecutive patients (78 female and 10 male), with a mean age of 39 years (range 15-79), was prospectively studied. All patients had been diagnosed with APS: 54 (61%) primary APS and 34 (39%) APS associated with systemic lupus erythematosus. A group of 200 apparently healthly blood donors was included in the study. Anti-HCV antibodies were investigated in the serum of all patients using a third-generation ELISA and confirmed by recombinant immunoblot assay. RNA-HCV was investigated in anti-HCV positive samples by polymerase chain reaction. Anticardiolipin, anti-beta2-glycoprotein I and antiprothrombin antibodies were evaluated by ELISA. Lupus anticoagulant was studied by coagulometric assays. RESULTS Only 2 (2.2%) patients showed positivity for anti-HCV antibodies, but none of them had clinical or biochemical signs of liver disease. Furthermore, RNA-HCV was not detected in serum of any of these patients. Lupus anticoagulant was positive in 57% of patients. Anticardiolipin antibodies were positive in 60% of patients, anti-beta2-glycoprotein I antibodies in 43% of patients, and antiprothrombin antibodies in 56% of patients. The prevalence of anti-HCV in blood donors was 1%. CONCLUSIONS The prevalence of anti-HCV in patients with APS is low and similar to that in healthy people in our area. HCV infection does not seem to be involved in the etiopathogenesis of this syndrome.

Budd-Chiari syndrome secondary to antiphospholipid syndrome: clinical and immunologic characteristics of 43 patients.

Budd-Chiari syndrome (BCS) is characterized by structural and functional abnormalities of the liver caused by obstruction to the outflow of hepatic venous blood (13). The consequent liver dysfunction depends on the extension and velocity of instauration of the obstruction. BCS is clinically characterized by abdominal pain, hepatomegaly, and ascites, and the clinical presentation may range from nearly asymptomatic to fulminant liver failure (9, 21). The etiology is unknown in a limited proportion of patients, and several myeloproliferative disorders and hypercoagulable states have been implicated, including polycythemia vera, essential thrombocythemia, paroxysmal nocturnal hemoglobinuria, antithrombin, protein C and protein S deficiency, resistance to activated protein C, factor V Leiden, G20210A factor II gene mutation, use of oral contraceptives, pregnancy, and postpartum state (11, 13, 34, 58). In some studies (41, 53), a relationship between BCS and elevated levels of antiphospholipid antibodies (aPL) has been suggested. The latter are a group of autoantibodies directed to a complex of phospholipids and proteins and include lupus anticoagulant (LA) and anticardiolipin antibodies (aCL). Several studies have shown that patients with aPL are prone to repeated episodes of thrombosis and spontaneous fetal losses. The association of aPL with these clinical events has been termed the antiphospholipid syndrome (APS) (28), and it is considered “primary” if not associated with other underlying disease (4) or “secondary” if it appears in association with other autoimmune disorders, mainly systemic lupus erythematosus (SLE) (17). In this report, we describe 4 new cases of patients with BCS and aPL. In addition, we review the literature supporting the idea that such an association may be a feature of APS, and present the clinical and immunologic characteristics of 43 patients with this association.

Thrombomodulin and induced tissue factor expression on monocytes as markers of diabetic microangiopathy: A prospective study on hemostasis and lipoproteins in insulin-dependent diabetes mellitus

Vascular complications are the main cause of morbidity in diabetes mellitus. To evaluate lipoprotein and hemostatic parameters and their relationship with clinically detectable microangiopathy, we studied 58 insulin‐dependent diabetes mellitus patients and 60 controls matched for age, sex, and body mass index. Thirteen patients presented clinically detectable microangiopathy (8 retinopathy and 5 both retinopathy and microalbuminuria). A cross‐sectional study of lipid profile, coagulation parameters, and a flow‐cytometric evaluation of tissue factor expression in normal monocytes induced by patient plasma were performed. Patients were re‐evaluated for microangiopathy in a 3‐year median follow‐up. Patients showed triglyceride enrichment in low (P = 0.00002) and high density lipoproteins (P = 0.004) and increased levels of D‐dimer (P < 0.00001), prothrombin fragment 1 + 2 (P < 0.00001), and thrombin‐antithrombin III complex (P = 0.0001). Patients with clinically detectable microangiopathy had increased type 1 plasminogen activator inhibitor (P = 0.00001), thrombomodulin (P = 0.02), and induced monocyte tissue factor expression (P < 0.00001). Nine patients developed clinically detectable microangiopathy in the follow‐up and the only predictive variable was increased induced tissue factor expression. In conclusion, in these patients elevated thrombin and fibrin generation reflects a hypercoagulable state but clinically detectable microangiopathy seems related to endothelial cell injury markers and to increased induced tissue factor expression on monocytes. Am. J. Hematol. 56:93–99, 1997.

The 4G/5G polymorphism of the type 1 plasminogen activator inhibitor gene and thrombosis in patients with antiphospholipid syndrome.

OBJECTIVE To investigate the relationship between the 4G/5G polymorphism of the type 1 plasminogen activator inhibitor (PAI-1) gene and thrombotic manifestations in patients with antiphospholipid syndrome (APS). METHODS We studied a total of 247 patients included in the following 4 groups: 70 patients with primary APS, 104 patients with systemic lupus erythematosus (40 with antiphospholipid antibodies [aPL] and clinical [secondary] APS, 13 with aPL but without clinical APS, and 51 with neither detectable aPL nor a history of thrombosis), 14 asymptomatic individuals with aPL, and 59 patients with thrombosis but without known thrombosis risk factors. A control group of 100 healthy individuals was also analyzed. PAI-1 4G/5G polymorphism was determined by polymerase chain reaction and endonuclease digestion. RESULTS The allele frequency of 4G/5G in controls was 0.47/0.53. There were no differences in allele distribution among patient groups or between patients and controls. However, a higher frequency of the 4G allele was observed in APS patients with versus those without thrombosis (0.57 versus 0.39; P < 0.05) (odds ratio [OR] 2.83, 95% confidence interval [95% CI] 1.18-6.76). This higher frequency of the 4G allele was attributable to the higher frequency in patients with versus those without arterial thrombosis (0.64 versus 0.43; P < 0.01) (OR 5.96, 95% CI 1.67-21.32), while patients with venous thrombosis had an allele distribution similar to that of those without venous thrombosis (0.49 versus 0.50; P not significant). There was a trend toward higher PAI-1 antigen and activity levels in APS patients and controls with the 4G/4G genotype, but this did not reach statistical significance. CONCLUSION The presence of the 4G allele of the 4G/5G polymorphism of the PAI-1 gene may be an additional risk factor for the development of arterial thrombosis in APS.

Antibodies to endothelial cells in Behçet's disease: cell-binding heterogeneity and association with clinical activity.

OBJECTIVES--To investigate the prevalence and characteristics of antibodies to endothelial cells (aEC) from large vessel and from microvasculature in a group of patients with Behçets disease (BD) to determine the relationship of these antibodies with clinical and laboratory features of the disease. METHODS--Thirty patients with BD were prospectively and consecutively studied. The aEC were determined by enzyme-linked immunosorbent assay (ELISA) using endothelial cells derived from human umbilical vein (large vessel) as well as from retroperitoneal adipose tissue (microvasculature). RESULTS--Fifteen patients (50%) had aEC, either directed to large vessel [8(26%) patients] or microvascular [13(43%) patients] endothelial cells. The percentage of active patients was significantly higher in the aEC-positive group [12(80%) patients] compared with the aEC-negative group [5(33%) patients] (p < 0.05). CONCLUSIONS--Patients with BD have a high prevalence of aEC when microvascular endothelial cells are used in the assay. These antibodies seem to be a marker of disease activity in this condition, previously considered as negative for autoantibodies.

Effect of recombinant human erythropoietin treatment on circulating reticulated platelets in uremic patients: Association with early improvement in platelet function

Recombinant human erythropoietin improves platelet function in uremia through the correction of anemia, but this effect can be seen also before the hematocrit rise. We studied 12 hemodialyzed patients (seven men, five women) who received recombinant human erythropoietin (40 IU kg−1 i.v., three times weekly) and were evaluated before treatment and after three doses; 24 control subjects were used. Platelet aggregation induced by adenosine 5′‐diphosphate (ADP), epinephrine, collagen, arachidonic acid, and ristocetin, and reticulated platelets determined by flow cytometry after staining with thiazole orange were measured. Platelet aggregation induced by all the agonists were impaired in uremic patients (P < 0.01), but ADP and ristocetin‐induced aggregations improved after treatment (P < 0.01). Hemodialyzed patients had less reticulated platelets than controls (P < 0.01). Reticulated platelets increased after three doses of treatment (P < 0.01). In conclusion, improvement of platelet function at early stages of recombinant human erythropoietin treatment may be attributed to the increase in young platelets detected as reticulated platelets. Am. J. Hematol. 59:105–109, 1998.

Vitamin K-dependent proteins GAS6 and Protein S and TAM receptors in patients of systemic lupus erythematosus: correlation with common genetic variants and disease activity

IntroductionGrowth arrest-specific gene 6 protein (GAS6) and protein S (ProS) are vitamin K-dependent proteins present in plasma with important regulatory functions in systems of response and repair to damage. They interact with receptor tyrosine kinases of the Tyro3, Axl and MerTK receptor tyrosine kinase (TAM) family, involved in apoptotic cell clearance (efferocytosis) and regulation of the innate immunity. TAM-deficient mice show spontaneous lupus-like symptoms. Here we tested the genetic profile and plasma levels of components of the system in patients with systemic lupus erythematosus (SLE), and compare them with a control healthy population.MethodsFifty SLE patients and 50 healthy controls with matched age, gender and from the same geographic area were compared. Genetic analysis was performed in GAS6 and the TAM receptor genes on SNPs previously identified. The concentrations of GAS6, total and free ProS, and the soluble forms of the three TAM receptors (sAxl, sMerTK and sTyro3) were measured in plasma from these samples.ResultsPlasma concentrations of GAS6 were higher and, total and free ProS were lower in the SLE patients compared to controls, even when patients on oral anticoagulant treatment were discarded. Those parameters correlated with SLE disease activity index (SLEDAI) score, GAS6 being higher in the most severe cases, while free and total ProS were lower. All 3 soluble receptors increased its concentration in plasma of lupus patients.ConclusionsThe present study highlights that the GAS6/ProS-TAM system correlates in several ways with disease activity in SLE. We show here that this correlation is affected by common polymorphisms in the genes of the system. These findings underscore the importance of mechanism of regulatory control of innate immunity in the pathology of SLE.

Incidental versus symptomatic venous thrombosis in cancer: a prospective observational study of 340 consecutive patients

BACKGROUND The clinical significance of incidental venous thrombosis (IVT) is uncertain. The objective of this study was to compare the clinical characteristics and the outcome of cancer patients with IVT with those of patients with symptomatic venous thrombosis (SVT). PATIENTS AND METHODS Prospective observational study enrolling consecutive cancer patients newly diagnosed with venous thromboembolism (May 2006-April 2009). Diagnosis of IVT was based on vascular filling defects in scheduled computed tomography scans in the absence of clinical symptoms. Anticoagulant therapy was routinely prescribed regardless of SVT or IVT. RESULTS IVT was diagnosed in 94 out of 340 (28%) patients. Patients with IVT were older (63.7 ± 10.5 versus 60.8 ± 10.5 years, P = 0.035), more frequently had metastatic cancer (82% versus 65%, P = 0.01) and were less likely to be receiving chemotherapy at the time of the thrombotic event (53% versus 67%, P = 0.018). Mean follow-up was 477 days. A lower risk of venous rethromboses was observed in patients with IVT (log-rank P = 0.043), with no differences in major bleeding and overall survival compared with SVT patients. CONCLUSIONS A high proportion of venous thrombotic events in cancer patients are diagnosed incidentally during scheduled imaging. Prospective controlled trials evaluating the optimal therapy in this setting are required.