Brahim Nsiri

MémoireLa thrombose veineuse cérébrale : étude étiologique prospective de 26 patients tunisiensCerebral venous thrombosis: Prospective etiological study of 26 Tunisian patients

PURPOSE The aim of the present study is to provide a clinical and etiological analysis of cerebral venous thrombosis (CVT) in the Tunisian population. METHODS This is a prospective monocentric study including 26 patients referred to the Neurology Department of the Military Hospital of Tunis between January 2005 and January 2008. The diagnosis of CVT was confirmed in all patients by magnetic resonance imaging (MRI) and angiography. The clinical and biological risk factors of cerebral venous thrombosis were analyzed. The average follow-up was 18 months (range six to 30). The outcome was assessed clinically with the modified Rankin scale and with MRI. RESULTS Mean age was 38.26 years, predominantly females (sex-ratio 4.2). The clinical onset was acute in 88.46% of the cases. Headache was the most common inaugural sign (84.6%). Lateral and superior longitudinal sinuses were the most commonly involved with equal frequency (61.53%). Parenchymal lesions were frequently noted (77%), especially hemorrhagic infarcts (46.15%). The causes of CVT were variable and usually combined (85%). Specifically, thrombophilia and obstetric-gynecological causes were predominant with a prevalence of 61.5 and 42.3%, respectively. Septic causes (38.46%) are also frequent, mainly oral infections (27%). Outcome was favorable in 77% of patients given heparin therapy, followed by oral anticoagulants and antibiotics as needed. CONCLUSION Our Tunisian population presented distinct clinical features compared with previous studies, including a high frequency of thrombophilia and gyneco-obstetrical disorders as well as infectious causes.

La thrombose veineuse cérébrale: étude étiologique prospective de 26 patients tunisiens

PURPOSE The aim of the present study is to provide a clinical and etiological analysis of cerebral venous thrombosis (CVT) in the Tunisian population. METHODS This is a prospective monocentric study including 26 patients referred to the Neurology Department of the Military Hospital of Tunis between January 2005 and January 2008. The diagnosis of CVT was confirmed in all patients by magnetic resonance imaging (MRI) and angiography. The clinical and biological risk factors of cerebral venous thrombosis were analyzed. The average follow-up was 18 months (range six to 30). The outcome was assessed clinically with the modified Rankin scale and with MRI. RESULTS Mean age was 38.26 years, predominantly females (sex-ratio 4.2). The clinical onset was acute in 88.46% of the cases. Headache was the most common inaugural sign (84.6%). Lateral and superior longitudinal sinuses were the most commonly involved with equal frequency (61.53%). Parenchymal lesions were frequently noted (77%), especially hemorrhagic infarcts (46.15%). The causes of CVT were variable and usually combined (85%). Specifically, thrombophilia and obstetric-gynecological causes were predominant with a prevalence of 61.5 and 42.3%, respectively. Septic causes (38.46%) are also frequent, mainly oral infections (27%). Outcome was favorable in 77% of patients given heparin therapy, followed by oral anticoagulants and antibiotics as needed. CONCLUSION Our Tunisian population presented distinct clinical features compared with previous studies, including a high frequency of thrombophilia and gyneco-obstetrical disorders as well as infectious causes.

The Effect of ACE I/D Polymorphisms Alone and With Concomitant Risk Factors on Coronary Artery Disease:

Background: Coronary artery disease (CAD), also known as atherosclerotic heart disease, is a leading cause of mortality and morbidity throughout the world. The role of insertion/deletion (I/D) polymorphisms of the angiotensin-converting enzyme (ACE) gene in the etiology of CAD remains to be more completely clarified. The aim of this study was to determine the role of the ACE I/D polymorphism in patients with CAD and to study the association together with traditional risk factors in assessing the risk of CAD. Methods: Our study population included 145 Tunisian patients with symptomatic CAD and a control group of 300 people matched for age and sex. All participants in the study were genotyped for the ACE I/D polymorphisms obtained by polymerase chain reaction amplification on genomic DNA. Results: Our analysis showed that the ACE D allele frequency (P < 10−3; odds ratio [OR] = 5.2; 95% confidence interval [CI] = 3.6-7.6) and DD genotype (P < 10−3; OR = 6.8; 95% CI = 4.4-10) are significantly more prevalent among patients with CAD than in controls and may be predisposing to CAD. We further found that the risk of CAD is greatly potentiated by several concomitant risk factors (smoking, diabetes, hypertension, dyslipidemia, and a family history of CAD). Conclusion: The ACE D allele may be predictive in individuals who may be at risk of developing CAD. Further investigations of these polymorphisms and their possible synergisms with traditional risk factors for CAD could help to ascertain better predictability for CAD susceptibility.

Role of methylenetetrahydrofolate reductase A1298C polymorphism in cerebral venous thrombosis.

The association between the methylenetetrahydrofolate reductase (MTHFR) gene and cerebral venous thrombosis (CVT) remains controversial. This study principally investigated the potential role of the MTHFR A1298C variant and CVT. The genotyping of the A1298C variant of the MTHFR gene was performed in 35 CVT patients and 200 healthy controls. The frequency of A1298C genotype among CVT patients was significantly higher compared with controls (P < 10−3), suggesting an association between this polymorphism and CVT. To our knowledge, there are no previous reports assessing the correlation between the MTHFR A1298C variant and CVT. Large study populations would be required to understand the contribution of this marker in the risk of CVT.

Role of the Apolipoprotein E Polymorphisms in the Development of Retinal Vein Occlusion in a Tunisian Population A Case–Control Study

Apolipoprotein E (APOE) is a member of the apolipoprotein gene family. APOE is polymorphic with 3 main allelic types: ∊2, ∊3, and ∊4. Certain of these alleles have been associated with higher vascular risk. However, the association of APOE genotypes with retinal biomarkers and risk of retinal stroke is less clear. This study evaluated the role of APOE polymorphisms in retinal vein occlusion (RVO). In the present study, 2-point mutations coding amino acid residues 112 and 158 were amplified using the polymerase chain reaction (PCR) from DNA extracted from Tunisian participants. APOE genotypes were determined by multiplex PCR followed by molecular hybridization. Eighty-eight patients (26 women and 62 men) and 100 age- and gender-matched healthy participants were enrolled. The statistical study revealed a higher frequency of the ∊4 allele in patients as compared to controls (27.3% vs 9%) with a significant association of the ∊4 allele with the disease (P < 10−3, Pa < 10−3, odds ratio [OR] = 3.8, 95% confidence interval [CI] = 2.1-6.8). The frequency of the ∊3 allele was significantly lower in the patients with RVO compared to the controls (60.2% vs 82.5%, respectively; P < 10−3, Pa < 10−3, OR = 0.32, 95% CI = 0.19-0.53). The ∊3 allele seems to be protective against the disease. There was no association between the APO ∊2 allele and RVO. The association of APOE allele and genotype with RVO requires further investigation in different populations.

HLA DRB1*03 as a possible common etiology of schizophrenia, Graves’ disease, and type 2 diabetes

BackgroundAutoimmune diseases and schizophrenia share many common features. Association studies confirm a shared genetic association in the human leukocyte antigen (HLA) region between schizophrenia and most autoimmune diseases. To our knowledge, the simultaneous syndromes of Graves’ disease (GD) and type 2 diabetes (T2D) in schizophrenia are rare in Tunisia.Case presentationWe report a case of a 42-year-old woman admitted to the department of psychiatry for an acute relapse of chronic schizophrenia. Her medical history revealed that she was followed for Graves’ disease and for a type 2 diabetes mellitus. A low-resolution HLA typing was performed by polymerase chain reaction sequence-specific primer (PCR-SSP) techniques according to determine the patient’s haplotype.ConclusionsOur study suggests that the HLA DRB1*03 allele may explain a common etiology underlying the co-morbidity of Graves’ disease, type 2 diabetes, and schizophrenia in our patient.

Association of FV G1691A Polymorphism but not A4070G With Coronary Artery Disease

Coronary artery disease (CAD) is one of the chief causes of death in the world. Several hypotheses have been promoted as for the origin of the disease, among which are genetic predispositions and/or environmental factors. The aim of this study was to determine the effect of factor V (FV) gene polymorphisms (Leiden, G1691A [FVL] and HR2 A4070G) and to analyze their association with traditional risk factors in assessing the risk of CAD. Our study population included 200 Tunisian patients with symptomatic CAD and a control group of 300 participants matched for age and sex. All participants were genotyped for the FVL and HR2 polymorphisms. Multivariate logistic regression was applied to analyze independent factors associated with the risk of CAD. Our analysis showed that the FVL A allele frequency (P < 10–3, odds ratio [OR] = 2.81, 95% confidence interval [CI] = 1.6-4.9) and GA genotype (P < 10–3, OR = 4.03, 95% CI = 2.1-7.6) are significantly more prevalent among patients with CAD compared to those controls and may be predisposing to CAD. We further found that the FVL mutation is an independent risk factor whose effect is not modified by other factors (smoking, diabetes, hypertension, dyslipidemia, and a family history of CAD) in increasing the risk of the disease. However, analysis of FV HR2 variation does not show any statistically significant association with CAD. The FVL polymorphism may be an independent risk factor for CAD. However, further investigations on these polymorphisms and their possible synergisms with traditional risk factors for CAD could help to ascertain better predictability for CAD susceptibility.

The Plasminogen Activator Inhibitor 1 4G/5G Polymorphism and the Risk of Alzheimer's Disease.

Objective: The aim of this study was to determine whether plasminogen activator inhibitor 1 (PAI-1) is associated with the risk of Alzheimer’s disease (AD) in Tunisian patients. Design and Methods: We analyzed the genotype and allele frequency distribution of the PAI-1 polymorphism in 60 Tunisian patients with AD and 120 healthy controls. Results: The results show a significantly increased risk of AD in carriers of the 4G/4G and 4G/5G genotypes versus the wild-type 5G/5G genotype (4G/4G: 28.33% in patients vs 10.0% in controls; P < 10−3; OR = 8.78; 4G/5G: 55.0% in patients vs 38.33% in controls; OR = 4.45; P < 10−3). The 4G allele was also more frequently found in patients compared with controls; P < 10−3; OR = 3.07. For all participants and by gender, homozygotic carriers (4G/4G) were at an increased risk of AD over heterozygotes and women were at an increased risk over their male genotype counterparts. The odds ratio for AD among 4G/4G carriers for any group was approximately twice that of heterozygotes in the same group. Women homozygotes ranked highest for AD risk (OR = 20.8) and, in fact, women heterozygotes (OR = 9.03) ranked higher for risk than male homozygotes (OR = 6.12). Conclusion: These preliminary exploratory results should be confirmed in a larger study.