Factor V Leiden and prothrombin gene G20210A mutation in children with cerebral thromboembolism.

We investigated whether there is an association between factor V Leiden (FVL) and/or prothrombin gene G20210A mutation (PT20210A) and cerebral thromboembolism in a pediatric Argentinean population. From May 1992 to January 2002, 44 consecutive children with arterial ischemic stroke (AIS) and 23 children with cerebral sinovenous thrombosis (SVT) were prospectively studied at a single center. The prevalence of both mutations was compared with a 102 age-matched controls. In children with AIS, the frequencies (patients vs. controls), odds ratio (OR), and 95% confidence interval (95% CI) for the presence of FVL were as follows: 2.3% vs. 2%, OR/95% CI, 1.16/0.2 to 13.2; P value = 0.99. No cases of PT20210A were found in this group. In children with SVT, the frequencies (patients vs. controls), OR, and 95% CI were as follows: FVL (4.3% vs. 2%, OR/95% CI, 2.27/0.22 to 6.2; P value = 0.99) and PT20210A (4.3% vs. 1%; OR/95% CI, 4.6/0.3 to 76.3; P value = 0.3354). One child with PT20210A also had an inherited protein C deficiency. In 12 (18%) out of the 67 children with cerebral thromboembolism, without the aforementioned mutations, other prothrombotic disorders were detected. Although a multi-center prospective study with a large number of Argentinean pediatric patients is needed to obtain considerable evidence, no association between factor V Leiden and/or prothrombin gene G20210A mutation and cerebral thromboembolism was found in this pediatric series.

Polymorphism of the lipoprotein lipase gene and risk of atherothrombotic cerebral infarction in the Japanese.

BACKGROUND AND PURPOSE: Lipid and lipoprotein abnormalities have been implicated in the pathogenesis of ischemic cerebrovascular disease and atherosclerosis. Lipoprotein lipase (LPL) plays an important role in plasma lipoprotein metabolism. Several studies have recently reported the presence of a relationship between Ser447Stop mutation of LPL and coronary artery disease. Other polymorphisms (HindIII and PvuII) of the LPL gene have already been shown to correlate significantly with dyslipidemia. We investigated whether these polymorphisms are associated with increased risk of ischemic cerebrovascular disease (CVD). METHODS: We recruited 177 CVD patients (atherothrombotic infarction, n=71; cardioembolic infarction, n=30; lacunar infarction, n=76) and 177 healthy control subjects. Subjects were genotyped for the Ser447Stop mutation and for HindIII/PvuII restriction fragment length polymorphisms of the LPL gene, and the findings were investigated for associations with the clinical subtypes of CVD and with lipid levels. RESULTS: The Ser447Stop mutation correlated significantly with CVD (0.107 versus 0.158; P=0.035). For the CG+GG versus CC genotype, the odds ratio between control subjects and CVD patients with atherothrombotic infarction was 0.42 (95% CI, 0.18 to 0.99) (P=0.046). Serum HDL cholesterol and triglyceride levels did not correlate significantly with the Ser447Stop genotype. HindIII polymorphism correlated significantly with CVD (0.234 versus 0.169; P=0.031), but the frequency of PvuII polymorphism was not significantly different between groups. CONCLUSIONS: Our results suggest that the Ser447Stop mutation of the LPL gene is a novel genetic marker for low risk of atherothrombotic cerebral infarction.

4G/5G polymorphism of the plasminogen activator inhibitor-1 gene and insertion/deletion polymorphism of the tissue-type plasminogen activator gene in atherothrombotic stroke.

BACKGROUND AND PURPOSE: Decreased fibrinolytic capacity due to increased plasminogen activator inhibitor-1 (PAI-1) activity and decreased tissue-type plasminogen activator (t-PA) activity has been associated with hypertension or atherothrombotic disorders. The aims of this study were to observe associations of the genetic polymorphism for PAI-1 and t-PA with hypertension and atherothrombotic stroke, and to elucidate whether impaired fibrinolytic activity in atherothrombotic stroke was related to atherothrombosis per se or to other risk factors such as hypertension. METHODS: Patients with atherothrombotic stroke (n = 60), hypertension (n = 100), and control subjects (n = 100) were enrolled. We genotyped all subjects for 4G/5G polymorphism in the promoter region of the PAI-1 gene and the Alu-repeat insertion/deletion (I/D) polymorphism in intron h of the t-PA gene by polymerase chain reaction and endonuclease digestion. RESULTS: The frequency of the 4G/4G genotype of PAI-1 was significantly higher in the atherothrombotic stroke patients than the control subjects (41.7 versus 21%; p = 0.005), but not in the hypertensive subjects. There was a significant association between 4G/4G genotype of PAI-1 and atherothrombotic stroke (adjusted odds ratio = 3.11, 95% confidence interval 1.18-8.15), adjusting for age, sex, total cholesterol, low-density lipoprotein, triglyceride, and body mass index. However, the number of the I/I genotype of t-PA in the atherothrombotic stroke or hypertensive patients was virtually identical to the control subjects. CONCLUSION: Our results suggest that the 4G/4G genotype of the PAI-1 gene is significantly associated with an increased risk of atherothrombotic stroke. This finding also supports that impaired fibrinolytic activity in atherothrombotic stroke is related to atherothrombosis per se, but not to hypertension, one of the most important risk factors of atherothrombotic stroke.

[Hereditary occlusive cerebroretinal vasculopathy in two sisters]. / Hereditäre okklusive zerebroretinale Vaskulopathie bei zwei Schwestern.

BACKGROUND: Retinal microvascular abnormalities associated with multiorgan disease may be observed in a number of systemic illnesses and syndromes. PATIENTS: Two sisters with identical signs of a hereditary cerebroretinal vasculopathy (occlusive retinal angiopathy--cerebral vasculopathy--microcephalus) were treated at the University Hospital of Saarland. COURSE: Photocoagulation for treatment of neovascular complications secondary to retinal ischemia was performed. In one eye a vitrectomy became necessary because of persistent vitreal hemorrhage. One sister died because of non treatable intracranial hypertension at the age of 22 years. CONCLUSIONS: Interdisciplinary work-up is important in patients with cerebroretinal disease. Neuropathologic evaluation including brain biopsy and neuroimaging plus ophthalmoscopy and pedriatic findings lead to the diagnosis of this rare hereditary, in this case most likely autosomal recessive condition. Photocoagulation may limit neovascular complications secondary to retinal ischemia. A specific form of treatment has, however, not yet been found.

Resistance to activated protein C as an etiology for stroke in a young adult: a case report.

Resistance to activated protein C (R-APC) is an inherited, autosomal dominant, coagulation abnormality that is increasingly recognized as an important etiology for thromboembolic disease and stroke in young adults. This report describes the case of a 27-year-old woman taking oral contraceptives who experienced an acute thrombotic right hemispheric stroke. Three days after rehabilitation admission (33 days after stroke) she developed a left femoral deep venous thrombosis (DVT) despite appropriate prophylaxis. Further diagnostic workup for the stroke and DVT identified R-APC, possibly exacerbated by oral contraceptives, as the etiology. Hematology consultation recommended lifetime anticoagulation with warfarin. The patient's family history revealed that a 19-year-old cousin had died of a stroke several years earlier. Several months after discharge, an acute DVT occurred in the patient's 28-year-old brother, who tested positive for factor V Leiden, a genetic abnormality closely associated with R-APC. A thrombotic stroke occurred in her grandfather a few months later, but he was not tested. Her father demonstrated a "borderline" positive R-APC test and probably represents the genetic link. Indications for patient and family screening regarding R-APC and other forms of hereditary thrombophilia and implications for rehabilitation medicine physicians are discussed.

High risk of cerebral-vein thrombosis in carriers of a prothrombin-gene mutation and in users of oral contraceptives.

BACKGROUND: Idiopathic cerebral-vein thrombosis can cause serious neurologic disability. We evaluated risk factors for this disorder, including genetic risk factors (mutations in the genes encoding factor V and prothrombin) and nongenetic risk factors (such as the use of oral contraceptive agents). We compared the prevalence of these risk factors in 40 patients with cerebral-vein thrombosis, 80 patients with deep-vein thrombosis of the lower extremities, and 120 healthy controls. The G1691A mutation in the factor V gene and the G20210A prothrombin-gene mutation, which are established genetic risk factors for venous thrombosis, were studied. We also assessed the use of oral contraceptives and other risk factors for thrombosis. RESULTS: The prevalence of the prothrombin-gene mutation was higher in patients with cerebral-vein thrombosis (20 percent) than in healthy controls (3 percent; odds ratio, 10.2; 95 percent confidence interval, 2.3 to 31.0) and was similar to that in patients with deep-vein thrombosis (18 percent). Similar results were obtained for the mutation in the factor V gene. The use of oral contraceptives was more frequent among women with cerebral-vein thrombosis (96 percent) than among controls (32 percent; odds ratio, 22.1; 95 percent confidence interval, 5.9 to 84.2) and among those with deep-vein thrombosis (61 percent; odds ratio, 4.4; 95 percent confidence interval, 1.1 to 17.8). For women who were taking oral contraceptives and who also had the prothrombin-gene mutation (seven patients with cerebral-vein thrombosis but only one control), the odds ratio for cerebral-vein thrombosis rose to 149.3 (95 percent confidence interval, 31.0 to 711.0). CONCLUSIONS: Mutations in the prothrombin gene and the factor V gene are associated with cerebral-vein thrombosis. The use of oral contraceptives is also strongly and independently associated with the disorder. The presence of both the prothrombin-gene mutation and oral-contraceptive use raises the risk of cerebral-vein thrombosis further.

PIP: The role of the prothrombin-gene mutation in idiopathic cerebral-vein thrombosis and its interaction with other risk factors was investigated in a study of 40 patients (9 men and 31 women) 15-64 years of age who presented to a thrombosis center in Milan, Italy, in 1991-97 after a first episode of this thrombosis. Also enrolled were 80 men and women randomly selected from patients screened at the same center during the study period after a first documented episode of proximal deep-vein thrombosis of the lower extremities. 120 healthy controls were matched to cerebral-vein thrombosis patients by sex, age, geographic origin, and education. 20% of patients with cerebral-vein thrombosis (odds ratio (OR), 10.2; 95% confidence interval (CI), 2.3-31.0), 18% of those with deep-vein thrombosis, and 3% of controls were carriers of the prothrombin-gene mutation. Factor V mutation was more prevalent in patients with cerebral-vein thrombosis (15%) than controls (3%) (OR, 7.8; 95% CI, 1.8-34.1), but the thrombotic risks associated with these two mutations were independent of each other. Oral contraceptive (OC) ever-use was more frequent among women with cerebral-vein thrombosis (96%) (OR, 22.1; 95% CI, 5.9-84.2) and deep-vein thrombosis (61%) (OR, 4.4; 95% CI, 1.1-17.8) compared with controls (32%). For the 7 women with cerebral-vein thrombosis who were both OC ever-users and had the prothrombin-gene mutation, the thrombotic risk rose to 149.3 (95% CI, 31.0-711.0). These findings show that there is a hypercoagulable state in 35% of patients with idiopathic cerebral-vein thrombosis. Although screening for the prothrombin-gene mutation in young women before they are prescribed OCs is unlikely to be cost-effective, carriers of the mutation who have had a thrombosis episode should discontinue OC use.

Increased rate of factor V Leiden mutation in patients with cerebral venous thrombosis.

We investigated the association between cerebral venous thrombosis and hereditary resistance to activated protein C (APC) in 12 consecutive German patients with non-fatal cerebral venous thrombosis and in 187 controls without a history of thrombotic disorder. Three patients (25%) had a mutation in the factor V Leiden gene against only one subject in the control group. This difference was significant (P < 0.05), with an odds ratio of 11.7 (1.5-87; 95% confidence interval). Two patients carrying the mutation had additional common risk factors for thrombosis, and 2 had a positive family history of thromboembolism. We conclude that inherited APC resistance by a mutation in factor V Leiden is an important risk factor in non-fatal cerebral venous thrombosis. We recommend testing for APC resistance and, if abnormal for factor V Leiden mutation in patients with cerebral venous thrombosis.

Bilateral renal vein thrombosis and venous sinus thrombosis in a neonate with factor V mutation (FV Leiden).

Bilateral renal vein thrombosis and venous sinus thrombosis were diagnosed within 3 weeks of birth in a full-term neonate. Heterozygosity for a factor V mutation leading to resistance against the anticoagulatory properties of activated protein C was found. Heparin therapy led to resolution of the thrombotic manifestations. With long-term oral anticoagulation, no relapse or other thrombotic event occurred during infancy.

Inherited prothrombotic risk factors and cerebral venous thrombosis.

Fifteen patients with cerebral venous thrombosis were ascertained retrospectively. Their case notes were reviewed, and stored or new blood was assayed for factor V Leiden (FVL) mutation, prothrombin gene mutation 20201A, and 5,10 methylene tetrahydrofolate reductase (MTHFR) C677T mutation. A clinical risk factor was identified in 13 patients--the oral contraceptive pill (5), puerperium (1), HRT (1), mastoiditis (1), dehydration (1), lumbar puncture and myelography (1), carcinoma (1), lupus anticoagulant (2). In addition, two patients had the FVL mutation and five (one of whom also had the FVL mutation) were homozygous for the MTHFR mutation. The latter showed a higher than expected frequency compared to 300 healthy controls from South Wales (OR 3.15.95% Cl 1.01-9.83). No patient had the prothrombin 20201A mutation. Two patients died and three had a monocular visual deficit following anticoagulation (13) or thrombolytic (2) treatment, but there was no association between the presence of a primary prothrombotic risk factor and outcome. These results confirm the importance of investigating patients for both clinical predisposing factors and primary prothrombotic states.

Fibrinogen Kaiserslautern (gamma 380 Lys to Asn): a new glycosylated fibrinogen variant with delayed polymerization.

An adult woman diagnosed with cerebral thrombosis following a caesarean section was found to have severely prolonged thrombin and reptilase times. Five other family members also had prolonged, but variable, thrombin and reptilase times. Analysis of purified fibrinogen on reducing SDS-PAGE revealed an additional band, in all family members, which migrated immediately below the normal B beta band. Western blotting indicated that this band was a gamma chain and endoglycosidase-F digestion established that it contained an additional oligosaccharide side chain. Partial acid hydrolysis localized the new oligosaccharide to the C-terminus of the gamma chain. Amplification of this region by PCR and subsequent DNA sequencing demonstrated a single base substitution altering the normal 380 Lys (AAG) codon to Asn (AAT), producing a new Asn-Lys-Thr glycosylation site. The propositus and one other family member were homozygous for this mutation but the remaining four family members were heterozygous. The polymerization of purified fibrin monomers from the propositus was grossly abnormal; however, the polymerization curve was almost normalized by the removal of terminal sialic acid residues. This suggests that the polymerization defect was primarily caused by additional negatively charged sialic acid residues present on the new oligosaccharide. Further analysis of the D domain of purified fibrinogen established that calcium binding to the high affinity site remained unaffected by the bulky carbohydrate side chain or negatively charged sialic acid residues.

The apolipoprotein E and beta-fibrinogen G/A-455 gene polymorphisms are associated with ischemic stroke involving large-vessel disease.

The relationship between the apolipoprotein E (apoE) and beta-fibrinogen G/A-455 polymorphisms and cerebrovascular disease (CVD) was examined in the present study. We compared 227 patients with the subtypes of CVD (large-vessel disease, lacunar stroke, cardiac embolism, or undetermined pathomechanisms) with 225 control subjects. The occurrence of apoE isoforms (E2, E3, and E4) and the beta-fibrinogen G/A-455 genotype was determined in these individuals. No differences in apoE polymorphisms or allele frequencies between the CVD patients and control subjects were found. However, analysis of apoE genotypes as a function of stroke subtype revealed that the apoE4 allele was significantly more common in those patients with macroangiopathy-associated CVD. The only CVD risk factor that distinguished patients with the E4 allele from those with other apoE genotypes was elevated cholesterol. No association between the beta-fibrinogen G/A-455 polymorphism and CVD was found. However, homozygosity for the A allele was more common in patients with CVD resulting from large-vessel disease. These data demonstrate that the apoE4 allele and the AA genotype of the beta-fibrinogen G/A-455 polymorphism occur significantly more frequently in patients with CVD resulting from stenosis of large, brain-supplying vessels. Such genetic analyses may further our understanding of the etiology of cerebrovascular disease.

A mutation in plasma platelet-activating factor acetylhydrolase (Val279-->Phe) is a genetic risk factor for stroke.

BACKGROUND AND PURPOSE: Platelet-activating factor (PAF) is a phospholipid with multiple actions that include thrombosis and inflammation. It is inactivated by a plasma enzyme, PAF acetylhydrolase. Deficiency of this enzyme in plasma is caused by a missense mutation in the gene (Val279-->Phe). We have studied a possible association of this mutation with the risk of stroke. SUBJECTS AND METHODS: We studied 120 consecutive patients with cerebral thrombosis. The control group consisted of 134 patients matched for age and sex with minor complaints but without stroke. Genomic DNA was analyzed for the mutant allele by a specific polymerase-chain reaction. Plasma PAF acetylhydrolase activity was determined by the method of Stafforini et al. RESULTS: The prevalence of the mutant gene was 43.4% in stroke patients (39.2% heterozygotes and 4.2% homozygotes), which was significantly higher than the 25.4% in control subjects (22.4% heterozygotes and 3.0% homozygotes) (chi 2 = 9.22, P < .01). The prevalence was slightly higher in stroke patients without hypertension than those with hypertension, but the difference was not significant. The patients with family histories of stroke had a slightly higher but not a significant prevalence of the mutant gene as compared with those without family histories of stroke. Plasma PAF acetylhydrolase activity was higher in patients than in control subjects, in normal subjects, or patients with a heterozygous genotype. CONCLUSIONS: These results suggest that plasma PAF acetylhydrolase deficiency may be a risk factor for stroke. This may explain the relatively high prevalence of stroke in Japan, as the mutation is more common among Japanese than Caucasians.

Polymorphism of the angiotensin-converting enzyme (ACE) gene in patients with thrombotic brain infarction.

The relationship between cerebrovascular disease and an insertion/deletion (I/D) polymorphism in intron 16 of the angiotensin-converting enzyme (ACE) gene is still being debated. We examined its role as a risk factor in patients with thrombotic brain infarction. The association between ACE polymorphism and ischemic stroke was examined in 181 patients with thrombotic brain infarction and 271 controls without strokes. The I/D polymorphism was examined using the polymerase chain reaction. Distributions of the ACE genotypes and alleles did not differ between the infarcted patients and the controls. Both distributions in patients with onset at age 60 years or younger were significantly higher than those in younger controls (genotype: chi 2 = 7.6, P = 0.02; allele: chi 2 = 5.6, P = 0.02). There were no significant differences in the distributions of ACE genotypes and alleles between the patients with lacunar infarcts and with cortical infarcts in all ages. There were also significant differences in the distribution of ACE genotypes and alleles between the younger and the elderly subgroup of patients with brain infarction (genotype: chi 2 = 12.9, P = 0.002; allele: chi 2 = 11.1, P = 0.0009). Furthermore, there was a significant decline in the frequency of the ACE D allele with increasing age in all patients with thrombotic brain infarction. These observations demonstrated a significant association between the ACE gene polymorphism and thrombotic brain infarction in patients age 60 years or younger in a Japanese population. Furthermore, there may be an association between the ACE D allele and mortality after cerebral infarction.

The factor V Leiden mutation: spectrum of thrombotic events and laboratory evaluation.

PURPOSE: This study aims to describe the spectrum of clinical thrombotic events and to compare the methods of laboratory evaluation for the newly described prothrombotic factor V Leiden mutation. METHODS: Specimens from 1376 patients with thrombotic events or their relatives were tested for the factor V Leiden mutation by polymerase chain reaction plus restriction digest from Jan. 1, 1995, to Mar. 31, 1996. Activated protein C (APC) resistance test data was available for 554 of these patients. Clinical information was available for 166 patients with the mutation. RESULTS: Of 1376 patients tested for factor V Leiden mutation, 270 (19.6%) were positive, with 12 homozygotes and 258 heterozygotes. Of 554 patients for whom APC resistance data was available, 221 (39.9%) had low APC resistance ratios (< or = 2.4); of these only 97 (43.9%) were factor V Leiden-positive. Among 333 samples with normal or elevated APC resistance ratios, 19 (5.7%) were later identified with the factor V Leiden mutation, despite the normal screening test. One hundred fourteen of 166 patients (68.7%) with the mutation had at least one thrombotic event, most commonly deep venous thrombosis and pulmonary embolus. Arterial cerebrovascular thrombotic events occurred in 11 patients (10%), and myocardial infarctions in eight (7%). The mean age of all patients with arterial thrombotic events was 45.4 years. CONCLUSIONS: The factor V mutation is a common cause of venous thromboses but may also be associated with the early presentation of arterial thrombotic events. The APC resistance test is a sensitive screening assay but has limitations of its specificity in clinical practice.

Vascular cell adhesion molecule-1 mRNA is expressed in immune-mediated and ischemic injury of the rat nervous system.

In this study we used nonradioactive in situ hybridization for the cellular localization of vascular cell adhesion molecule-1 (VCAM-1) mRNA in immune-mediated, ischemic and degenerative diseases of the rat nervous system. In the acute phase of experimental autoimmune encephalomyelitis and neuritis VCAM-1 mRNA was expressed not only on the luminal surface of inflamed vessels but also in perivascular cells suggesting a functional role of VCAM-1 in both endothelial adhesion and local restimulation of autoantigen-specific T cells. Accordingly, perivascular T cell accumulation was most pronounced at sites of local VCAM-1 mRNA expression. In addition, VCAM-1 mRNA was detected in the border zone around photochemically induced cerebral infarcts which is the predeliction site of T cell infiltration and expression of immune activation markers during the first week after ischemia. VCAM-1 mRNA was absent from the center of the infarcts as well as axotomized central and peripheral nerves undergoing Wallerian degeneration. These data indicate that VCAM-1-mediated adhesion processes are involved in immune-mediated and ischemic diseases of the nervous system but not in T cell-independent macrophage recruitment during Wallerian degeneration.