Joan Monteagudo

A Randomized Unblinded Pilot Study Comparing Albumin Versus Hydroxyethyl Starch in Spontaneous Bacterial Peritonitis

The administration of albumin improves circulatory function, prevents hepatorenal syndrome, and reduces hospital mortality in patients with cirrhosis and spontaneous bacterial peritonitis. This randomized unblinded pilot study compared the effect of albumin (10 patients) and the synthetic plasma expander hydroxyethyl starch 200/0.5 (10 patients) on the systemic hemodynamics of patients with spontaneous bacterial peritonitis. Baseline measurements were performed within 12 hours after diagnosis of infection. Patients then received 2 doses of the volume expander (1.5 g/kg body weight after baseline measurements and 1 g/kg body weight on day 3). Measurements were repeated after infection resolution. Treatment with albumin was associated with a significant increase in arterial pressure and a suppression of plasma renin activity, indicating an improvement in circulatory function. This occurred in the setting of a significant expansion of central blood volume (increase in cardiopulmonary pressures and atrial natriuretic factor) and an increase in systolic volume and systemic vascular resistance. In contrast, no significant changes were observed in these parameters in patients treated with hydroxyethyl starch. Von Willebrand–related antigen plasma levels significantly decreased in patients treated with albumin but not in those treated with hydroxyethyl starch. Serum nitrates and nitrites increased in patients treated with hydroxyethyl starch but not in those treated with albumin. These data suggest an effect of albumin on endothelial function. In conclusion, albumin but not hydroxyethyl starch improves systemic hemodynamics in patients with spontaneous bacterial peritonitis. This effect is due not only to volume expansion but also to an action on the peripheral arterial circulation. (HEPATOLOGY 2005.)

Hypercoagulable State in Patients With Antiphospholipid Syndrome Is Related to High Induced Tissue Factor Expression on Monocytes and to Low Free Protein S

Antiphospholipid antibodies (aPLs) are associated with thrombosis, but the mechanisms of this thrombotic tendency are unknown. We studied 56 patients 612 with systemic lupus erythematosus [SLE] and aPLs and previous thrombosis, 12 with SLE and aPLs but no thrombosis, 15 with SLE without aPLs or thrombosis, 11 with primary antiphospholipid syndrome with thrombosis, and 6 asymptomatic subjects with aPLs) to investigate the ability of aPLs to induce tissue factor (TF) expression on human normal monocytes. A double direct immunofluorescence technique (anti-CD14 and anti-TF) was used, and procoagulant activity in viable and disrupted cells was measured after plasma incubation for 6 hours at 37 degrees C with normal mononuclear cells. Hemostasis regulatory proteins, prothrombin fragment 1 + 2, and thrombin-antithrombin III complex levels were determined. Increased TF expression and procoagulant activity were observed using plasma samples from SLE patients with aPLs and thrombosis (P < .01) and from primary antiphospholipid syndrome patients (P < .01) but not from patients with SLE and aPLs but no thrombosis, patients with SLE without aPLs, or asymptomatic patients with aPLs. Purified aPL immunoglobulins from one primary antiphospholipid syndrome and two SLE patients added to normal plasma showed a significant increase in both TF expression and procoagulant activity (P < .05) compared with purified aPL from two SLE patients without thrombosis. The addition of nonspecific IgG from three SLE patients without aPLs and from three control subjects did not increase TF expression. Low free protein S was seen in eight patients. Increased TF expression and low free protein S correlated with thrombosis (P < .01) and with higher prothrombin fragment 1 + 2 and thrombin-antithrombin III values (P < .01). These observations may contribute to a further understanding of the thrombotic risk in aPL patients.

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.

Double heterozygosity polymorphisms for platelet glycoproteins Ia/IIa and IIb/IIIa increases arterial thrombosis and arteriosclerosis in patients with the antiphospholipid syndrome or with systemic lupus erythematosus

Objective: We analysed the genetic polymorphisms in platelet glycoproteins (GP) Ib-α, Ia/IIa and IIb/IIIa and their correlation with the development of arterial thrombosis and preclinical arteriosclerosis in patients with antiphospholipid syndrome (APS) or with systemic lupus erythematosus (SLE). Methods: We included 131 patients with APS (86 with primary APS and 45 with APS associated with SLE), 102 patients with SLE and 160 healthy controls. GP Ib-α VNTR polymorphism, GP Ia/IIa 807 C/T polymorphism and GP IIb/IIIa PlA1/2 polymorphism were determined by polymerase chain reaction. Thrombotic events were assessed clinically and confirmed by objective methods. The presence of preclinical arteriosclerosis was evaluated by a carotid ultrasound study in a subgroup of 70 patients with SLE measuring the intima-media wall thickness and the presence of arteriosclerotic plaque. Results: A total of 50 episodes of arterial thrombosis in 36 patients with APS have been registered. We found a significant correlation between the 807 T/T genotype of GP Ia/IIa and arterial thrombosis (22% vs 7%, p = 0.04; OR 3.59, 95% CI 1.20 to 10.79). The VNTR Ib-α and P1A1/2 IIb/IIIa polymorphisms were not associated with arterial thrombosis in patients with APS when individually analysed. The coexistence of both 807 T and PlA2 alleles increased the arterial thrombosis risk (28% vs 7%, p = 0.005; OR 4.84, 95% CI 1.67 to 13.96). In patients with SLE, no relationship was found between the presence of carotid arteriosclerotic plaque and separate polymorphisms of platelet GP. The coexistence of alleles 807 T of GP Ia/IIa and PlA2 of GP IIb/IIIa was associated with the presence of carotid plaque (35% vs 4%, p = 0.002; OR 12.92, 95% CI 2.39 to 69.81). Conclusions: The T/T genotype of 807 C/T polymorphism of GP Ia/IIa may be an additional risk for the development of arterial thrombosis in APS. The coexistence of both 807 T and PlA2 alleles increased the arterial thrombosis risk in patients with APS and preclinical arteriosclerosis in patients with SLE.

Thrombin-activatable fibrinolysis inhibitor genetic polymorphisms as markers of the type of acute coronary syndrome.

INTRODUCTION In patients with coronary disease at risk of acute coronary events it is unclear which biological factors could predict the type of acute coronary syndrome clinical presentation. The aim of the study was to investigate the role of genetic polymorphisms in key proteins in fibrinolysis in the type of acute coronary syndrome. MATERIALS AND METHODS 248 patients with acute coronary syndrome (unstable angina or myocardial infarction) (77% male, mean age 60.75 SD 13.30years) were prospectively recruited. PAI-1 (type-1 plasminogen activator inhibitor) 4G/5G and TAFI (thrombin-activatable fibrinolysis inhibitor) Ala147Thr, C+1542G, and Thr325Ile polymorphisms were determined by PCR. RESULTS 147 (59.3%) patients presented with ST-segment elevation acute coronary syndrome (all Q-wave myocardial infarction), and 101 (40.7%) with non-ST-elevation acute coronary syndrome (52 non-Q wave myocardial infarction, and 49 unstable angina). Homozygous TAFI +1542G and TAFI 325Ile genotypes were less prevalent in patients with ST elevation acute coronary syndrome (p<0.001, OR: 0.22, 95% CI 0.10-0.50 and p<0.001, OR: 0.25, 95% CI 0.11-0.55, respectively). There were no differences in TAFI Ala147Thr or PAI genotype distribution between ST elevation and non-ST elevation acute coronary syndrome. In the multivariate analysis including clinical variables, the best model for ST elevation acute coronary syndrome included TAFI +1542GG (p<0.001, OR: 0.17, 95% CI 0.07-0.30), age (in years, p<0.005, OR: 0.97, 95% CI 0.94-0.98) and dyslipidemia (p<0.005, OR: 2.33, 95% CI 1.42-3.80). CONCLUSION TAFI polymorphism C+1542G and Thr325/Ile are related to the type of acute coronary syndrome. Patients with coronary disease would benefit from individualized cardiovascular prophylaxis based on genetic risk.

Solid cancer, antiphospholipid antibodies, and venous thromboembolism☆

The pathogenic role of antiphospholipid antibodies (aPL) in the development of venous thromboembolism (VTE) in patients with malignancies has not been established. From May 2006 to April 2008, 258 consecutive patients with solid-organ malignancies who developed VTE (VTE+) were recruited. A group of 142 patients matched for age, sex and tumor type cancer patients without VTE (VTE-) and an age-and-sex matched group of 258 healthy subjects were also included. A second blood sample was taken in positive aPL patients at least 12 weeks later. Twenty-one (8.1%) VTE+ patients, 2 (1.4%) VTE- patients (p=0.006) and 2 (0.8%) healthy subjects (p<0.001) were positive for aPL. Persistent aPL positivity was observed in only 4 out of 15 available VTE+ patients. No differences in demographic characteristics, clinical pattern and outcome were observed in VTE+ patients according to aPL status. The low prevalence and transience of aPL positivity in patients with solid-organ malignancies with VTE argues against a pathogenic role in the development of thrombosis in this setting. The published evidence of the relationship between cancer, aPL, and thrombosis is reviewed.

Factor XIII-A subunit Val34Leu polymorphism is associated with the risk of thrombosis in patients with antiphospholipid antibodies and high fibrinogen levels

Recent reports have described the factor XIII A subunit (FXIII-A) Val34Leu polymorphism as a protective factor against venous and arterial thrombosis. The aim of this study was to investigate the association between the FXIII-A Val34Leu polymorphism, its interaction with fibrinogen concentration, and thrombosis in patients with antiphospholipid antibodies (aPL). We included 172 consecutive patients with aPL: 88 with primary antiphospholipid syndrome (APS), 38 with APS associated with systemic lupus erythematosus (APS-SLE), 32 with SLE and aPL but without APS (SLE-aPL), and 14 asymptomatic individuals with aPL (A-aPL). The FXIII-A Val34Leu polymorphism was assessed by polymerase chain reaction techniques. We found no significant differences in FXIII-A Leu34 allele frequencies between primary APS (allele frequency 0.22), APS-SLE (0.23), SLE-aPL (0.22) and A-aPL (0.32) patients, or between patients with (0.21) and without thrombosis (0.26). FXIII-A Leu34 allele frequencies were significantly lower in patients with thrombosis and those in the upper fibrinogen tertile (>3.40 g/l) (allele frequency 0.07) compared with patients without thrombosis in the upper fibrinogen tertile (0.29) and patients with (0.29) and without (0.25) thrombosis in the mid- and lower fibrinogen tertiles. The FXIII-A Leu34 allele had a protective effect against thrombosis in patients in the upper fibrinogen tertile (odds ratio [OR] = 0.20, 95% confidence interval [CI] 0.07-0.60) but not in those in the other tertiles (OR = 1.20, 95% CI 0.67-2.16). The FXIII-A Leu34 allele seems to have a protective effect on the development of thrombosis in patients with aPL, but only in those with high plasma fibrinogen values.

Asialo von Willebrand factor enhances platelet adhesion to vessel subendothelium.

Native von Willebrand factor (N-vWF) binds to platelets activated by thrombin, ADP or ristocetin. Asialo vWF (As-vWF) induces platelet aggregation in absence of platelet activators. N-vWF mediates platelet adhesion to vessel subendothelium at high shear rates. We have investigated the role of As-vWF in supporting platelet deposition to rabbit vessel subendothelium at a shear rate of 2,000 sec-1, using the Baumgartner perfusion system. We have studied the effects of the addition of As-vWF (from 2 to 12 micrograms/ml) to perfusates consisting of washed red blood cells, 4% human albumin and washed platelets. Our results show a significant increase in platelet deposition on subendothelium (p less than 0.01) in perfusions to which As-vWF had been added. Blockage of the platelet glycoproteins Ib and IIb/IIIa (GPIb and GPIIb/IIIa) by specific monoclonal antibodies (LJIb1 and LJCP8, respectively) resulted in a decrease of platelet deposition in both types of perfusates prepared with N-vWF and As-vWF. Our results indicate that As-vWF enhances platelet deposition to vessel subendothelium under flow conditions. Furthermore, they suggest that this effect is mediated by the binding of As-vWF to platelet membrane receptors, which in turn, promote platelet spreading and adhesion to the subendothelium.

Ristocetin induces platelet aggregation: a morphological demonstration

Changes in the morphology of human platelets induced by ristocetin in platelet‐rich plasma (PRP) have been analysed at the ultrastructural level by means of a tannic acid procedure. Studies were also undertaken to measure the release of serotonin. Modifications of the aggregation tests induced by apyrase, a monoclonal antibody (Mab) to GPIIb/ IIIa and by EDTA were also investigated. Transmission electron microscopy revealed that ristocetin precipitated adhesive proteins on the platelet membrane. An electron‐dense deposit was seen within 20s after ristocetin was added. When experiments were carried out in the aggregometer cuvette during stirring, groups of platelets became activated, changed their shape, and finally aggregated releasing part of their contents. The morphology of aggregates did not differ from those formed in the presence of ADP. Aggregation studies demonstrated that a Mab to GPIIb/IIIa modified the extent and the rate of the aggregation curve when RIPA was performed in citrated platelet‐rich plasma (c‐PRP), while apyrase modifies the extent, but not the slope, of the curve. Neither the antibody nor apyrase modified RIPA when it was performed in PRP obtained in the presence of EDTA. All this evidence suggests that RIPA in c‐PRP, besides reflecting the interaction of GPIb with vWF, may also test other mechanisms of the platelet function including: assembly of GPIIb/IIIa complex, interaction of fibrinogen with this glycoprotein complex, and possibly the release reaction.