[Polymorphism of the plasminogen activator inhibitor type 1 gene, plasminogen level and thrombosis in patients with antiphospholipid syndrome].

The frequency of venous and arterial thromboses and plasminogen level were investigated in 78 patients with antiphospholipid syndrome (APS), 35 of whom with systemic lupus erythematosus (SLE+APS) and 43 - with primary APS (PAPS). The levels and genotype of plasminogen activator inhibitor type 1 (PAI-1) were determined in 45 patients with APS, of whom 21 patients with SLE + APS and 24 patients with PAPS. A control group included 10 healthy individuals without autoimmune disease signs and thromboses on period of investigation and in past history. It was shown for the first time that for one third of 67 patients with APS and thromboses high positive levels of antiphospholipid antibodies (aPL) are associated with low plasminogen levels. The levels of PAI-1 antigen measured by ELIZA method, which detects active, latent and bound with plasminogen activator PAI-1, were opposed with frequency of thromboses in APS patients. Correlation between the high and increased levels of PAI-1 and high positive aPL levels was found for one third of 43 patients with APS and thrombosis. One of the possible mechanisms of this interconnection was considered. It was shown that arterial and, to a more extent, venous thromboses are associated with the 4G/5G polymorphism of PAI-1 gene and high plasma level of the inhibitor in 79% of APS patients. At the presence of the 4G allele patients with SLE+APS had higher PAI-1 levels than patients with PAPS. The obtained results show that measuring the levels of plasminogen and PAI-1 as well as the 4G/5G polymorphism of PAI-1 gene which is associated with thromboses may have the practical significance for identification of high risk of thrombosis in APS patients.

[Plasminogen activator inhibitor type 1 gene polymorphism and thromboses in patients with antiphospholipid syndrome].

AIM: To estimate the prevalence of plasminogen activator inhibitor type 1 (PAI-1) gene polymorphism in patients with antiphospholipid syndrome (APS) and its implication in vascular disorders. SUBJECTS AND METHODS: The investigation enrolled 138 patients: 103 with APS, including 47 with systemic lupus erythematosus (SLE) + APS and 56 with primary APS (PAPS), 15 with SLE without APS, 20 with idiopathic thrombosis (IT), a control group (30 apparently healthy individuals). Thrombosis at various sites was recorded in 91 (88%) of the 103 patients with APS. The authors analyzed both the presence of thrombotic events in all the groups and the number of cases of thrombosis in each patient. Antiphospholipid antibodies, such as lupus anticoagulant, anticardiolipin antibodies, and anti-beta2-glycoprotein type 1 antibodies, were studied in all the patients. To diagnose a genotype in patients by the code encoding for PAI-1, DNA isolated from peripheral blood by standard methods was used and further investigated by real-time polymerase chain reaction. RESULTS: Out of 91 patients with APS and thrombosis, 27 (30%) had the 4G/4G genotype, which corresponded to homozygous mutation in the PAI-1 gene, 50 (55%) had the 4G/5G genotype (heterozygous mutation), and 14 (15%) had the 5G/5G (a normal genotype). The PAI-1 4G/5G genotype was present in 22 (70%) of 31 patients with SLE + APS and lower limb deep vein thrombosis versus 17 (470%) of 36 patients with PAPS (odds ratio (OR) 2.73; 95% confidence interval (CI), 0.89 to 8.59; p = 0.08) and in 9 (90%) of 10 patients with SLE + APS and pulmonary artery thromboembolism versus 8 (40%) of 20 patients with PAPS (OR 13,5; 95% CI, 1.23 to 344.98; p = 0.02). The incidence of thrombosis per 100 person-years was higher in the PAI-1 4G/4G and 4G/5G groups: 35.4 and 28.1 cases per 100 person-years, respectively. Thromboses were least often in the group of patients with the PAI-1 5G/5G genotype (18.6). CONCLUSION: The prevalence of the PAI-1 5G/5G genotype in patients with APS and thrombosis was significantly lower than in those with SLE without APS or thrombosis. The 4G/5G polymorphism in APS in the presence of SLE was associated with venous thromboembolisms whereas in PAPS there was no relationship between the PAI-1 genotype, a history of thrombosis, and its localization.

[Morphological signs of mitochondrial cytopathy in skeletal muscles and micro-vessel walls in a patient with cerebral artery dissection associated with MELAS syndrome].

Skin and muscles biopsy specimens of a patient harboring A3243G mutation in mitochondrial DNA, with dissection of internal carotid and vertebral arteries, associated with MELAS were studied using histochemical and electron-microscopy techniques. Ragged red fibers, regional variability of SDH histochemical reaction, two types of morphologically atypical mitochondria and their aggregation were found in muscle. There was correlation between SDH histochemical staining and number of mitochondria revealed by electron microscopy in muscle tissue. Similar mitochondrial abnormality, their distribution and cell lesions followed by extra-cellular matrix mineralization were found in the blood vessel walls. In line with generalization of cytopathy process caused by gene mutation it can be supposed that changes found in skin and muscle microvessels also exist in large cerebral vessels causing the vessel wall "weakness", predisposing them to dissection.

[Polymorphism of 5,10-methylenetetrahydropholate reductase, prothrombin, and coagulation factor V genes in young patients with ischemic stroke].

The study included 142 patients (87 women, 55 men) (mean age 36.2 +/- 8.3 yr) after ischemic stroke caused by dissection of cerebral arteries (D) (n = 37), anti-phospholipid syndrome (APS) (n = 55) or cardiogenic embolism (CE) (n = 11). Stroke of unknown origin (cryptogenic) was diagnosed in 39 patients. Mutations of 5,10-methylenetetrahydropholate reductase (MTGPR), prothrombin, and coagulation factor V genes were documented by PCR in 38, 0, 3% of D cases, 55.9, 9, 13% of APS cases, 73, 9, 0 CE cases, 57, 5, 0% of cases with cryptogenic stroke compared with 43, 0, 0% in controls. Mutations in MTGPR gene in CE cases, prothrombin gene in APS and CE cases, coagulation factor V gene in APS cases occurred more frequently than in control (p < 0.05). They, were more frequent in APS/CE than in D (p < 0.05). Mutation rate in cryptogenic stroke was not significantly different from that in control (p < 0.05). It is concluded that the above mutations are not involved in pathogenesis of cryptogenic stroke, whereas those of prothrombin and coagulation factor V genes may enhance the thrombogenic potential in APS and CE patients. The role of MTGPR gene mutation in pathogenesis of cardiogenic stroke needs clarification.

[Recurrent thromboses and hemorrhagic complications in patients with antiphospholipid syndrome during therapy with warfarin plus aspirin].

AIM: To estimate the frequency of relapses of thrombotic and hemorrhagic complications during moderately intensive therapy for antiphospholipid syndrome (APS) with warfarin with and without aspirin. SUBJECTS AND METHODS: Eighty-two patients diagnosed as having the antiphospholipid syndrome were examined. Group 1 patients (n = 49) received warfarin alone as an antithrombotic drug; Group 2 patients (n = 33) had a combination therapy with warfarin plus aspirin. The efficiency of therapy was evaluated from the number and rate of recurrences of thromboses and transient ischemic attacks (TIA) and its safety was assessed from the frequency and number of hemorrhages during the study. The genetic variants of cytochrome P450 CYP2C9 were determined in 52 of the 82 patients; mutations in the gene for vitamin K epoxide reductase complex 1 (VCORC1) were revealed in 22 patients. RESULTS: During the follow-up, antithrombotic therapy was ineffective in 18.4 and 36.6% of the Groups 1 and 2 patients, respectively (p = 0.07). The rate of poor outcomes (thromboses and TIA) was 7 and 14.8 cases per 100 person-years, respectively. The first six months of warfarin therapy proved to be most risky for thrombotic events to occur--this period was responsible for 37% of bleedings. Hemorrhagic complications of antithrombotic therapy developed in 46.9 and 60.6% of Groups 1 and 2 patients, respectively (p = 0.26). Major hemorrhages were observed more frequently in the combination (warfarin plus low-dose aspirin) therapy group than in the warfarin monotherapy group. Mutant cytochrome P450 gene variants (CYP2C9*2 and CYP2C9*3) were present in 38.5% of the patients; VCORC1 gene mutations were observed in 27.3%. The number of nasal and gingival hemorrhages was increased in patients with CYP2C9*3 and homozygous VCORC1 gene mutations. CONCLUSION: Moderately intensive warfarin therapy (international normalized ratio 2.0-3.0) could generally reduce the frequency of recurrent thrombotic events by at least 2-fold as compared with that before warfarin administration. The efficiency of using warfarin alone or in combination with aspirin in APS was found to be similar; and its safety was higher during monotherapy therefore it is undesirable to combine warfarin with antiaggregants in real clinical practice. The determination of CYP2C9 and VCORC1 genotypes in patients with APS before warfarin use allows excessive hypocoagulation and related hemorrhages to be avoided.

[Warfarin in the treatment of antiphospholipid syndrome].

AIM: To assess efficacy and safety of warfarin therapy and its combination with low-dose acetylsalicylic acid (ASA) in antiphospholipid syndrome (APS). MATERIAL AND METHODS: The trial enrolled 60 APS patients. They were divided into two groups: group 1 (n = 39) on antithrombotic therapy with warfarin; group 2 (n = 21) on combined therapy with warfarin and ASA. Efficacy of the treatments was assessed by the number and frequency of thrombosis recurrences and transient ischemic attacks (TIA) while safety was evaluated by frequency and number of hemorrhages during the study. Genetic variants of cytochrome P450 (CYP2C9*1, CYP2C9*2 and CYP2C9*3) were studied in 30 patients (25 females, 5 males) with APS. CYP2C9 gene genetic variants were determined by polymerase chain reaction and restrictase analysis. RESULTS: The thrombosis rate was 19.6 per 100 man-day, TIA rate was not less than 8 per 100 man-day, total rate of thrombotic complications (thromboses and TIA) before warfarin individual dose adjustment--27.6 per 100 man-day. Doses of anticoagulant were adjusted and the patients on treatment were followed up for 15.7 months, on the average. For this period thrombosis occurred in 6 cases (7.6 per 100 man-day), TIA also in 6 cases (7.6 per 100 man-day). This corresponded to thrombotic complications rate 15.1 per 100 man-year. Hemorrhages (major and minor) occurred in 19 (48.7%) patients of group 1 and in 13 (61.9%) patients of group 2 (p = 0.33). Total rate of CYP2C9*2 and CYP2C9*3 carriage was 36.7%. The CYP2C9*2 variant was detected in 7 (23.3%) patients, who were all heterozygous carriers. The CYP2C9*3 variant was seen in 4 (13.3%) patients: 3 heterozygous and 1 homozygous. Females of reproductive age with mutations had more frequent menorrhagies than carriers of a wild-type variant. Patients with CYP2C9*3 had also more frequent nasal hemorrhages and gingival bleeding (p = 0.005) compared to carriers of CYP2C9*1 and CYP2C9*2. Episodes of MHO rise > 5.0 in warfarin therapy were observed in 50% carriers of CYP2C9*3 and in none homozygous carriers of CYP2C9*1 (p = 0.024). CYP2C9*3 patients needed lower maintenance doses of warfarin, in CYP2C9*1 and CYP2C9*2 patients anticoagulant doses were comparable. CONCLUSION; Efficacy of warfarin for secondary prophylaxis of thrombosis was found similar to that of warfarin use in combination with low-dose ASA (MHO 2.0-3.0). Safety of monotherapy was higher. Determination of CYP2C9 genotype in APS patients before treatment with oral anticoagulants may help in planning individual policy and in reducing the risk of warfarin overdosage at the start of therapy.

[Mutations of genes associated with thromboses in ischemic stroke in patients with primary antiphospholipid syndrome].

AIM: To study factor V Leiden, prothrombin (G1691A), 5, 10-methylenetetrahydrofolate reductase (MTHFR, C677T) mutations in patients with primary antiphospholipid syndrome (PAPS) and cerebrovascular disease (CVD). MATERIAL AND METHODS: We studied 44 patients (38 female, 6 male, mean age 41.6 +/- 11.6 years) with PAPS and CVD. Detection of mutations was carried out using polymerase chain reaction. RESULTS: Heterozygous factor V Leiden mutation was found in 11% patients, heterozygous prothrombin mutation--in 9%, heterozygous and homozygous MTHFR mutation--in 50% and 9%, respectively. The severity of CVD, frequency of clinical manifestations related to non-cerebral arterial and venous thrombosis did not differ between the patients with and without mutations or there was a tendency to less frequent occurrence of these manifestations in patients with mutations. Patients with heterozygous factor V Leiden mutation, heterozygous prothrombin mutation or homozygous MTHFR mutation less frequently developed recurrent ischemic stroke than patients without these mutations (8% versus 44%, p < 0.02). CONCLUSION: It is suggested that mutations studied do not play a significant role in development of cerebral and systemic thrombosis in patients with PAPS. The leading role belongs to antiphospholipid antibodies (aPL). Sometimes these mutations may protect from thrombogenic aPL action. This could underlie less frequent development of recurrent ischemic stroke in patients with mutation.