Mitochondrial DNA and Alzheimer's disease: a first case-control study of the Tunisian population.

BACKGROUND: Alzheimer's disease (AD) is the most common neurodegenerative disorder in humans and presents a major health problem throughout the world. The etiology of AD is complex, and many factors are implicated, including mitochondria. Mitochondrial alteration has been proposed as a possible cause of AD. Therefore, several studies have focused on finding an association between inherited mitochondrial DNA variants and AD onset. METHODS: In this study, we looked, for the first time, for a potential association between mitochondrial haplogroups or polymorphisms and AD in the Tunisian population. We also evaluated the distribution of the major genetic risk factor for AD, the apolipoprotein E epsilon 4 (APOE ε4), in this population. In total, 159 single-nucleotide polymorphisms (SNPs) of mitochondrial DNA haplogroups were genotyped in 254 individuals (58 patients and 196 controls). An additional genotyping of APOE ε4 was performed. RESULTS: No significant association between mitochondrial haplogroups and AD was found. However, two individual SNPs, A5656G (p = 0.03821, OR = 10.46) and A13759G (p = 0.03719, OR = 10.78), showed a significant association with AD. APOE 4 was confirmed as a risk factor for AD (p = 0.000014). CONCLUSION: Our findings may confirm the absence of a relation between mitochondrial haplogroups and AD and support the possible involvement of some inherited variants in the pathogenicity of AD.

Extensive longitudinal myelitis due to cytomegalovirus infection.

Neurological cytomegalovirus (CMV) infections especially extensive longitudinal myelitis are extremely rare in immunocompetent adults. However, we hereby report a case of cervical, thoracic, and lumbosacral myelitis caused by CMV infection in a healthy adult patient. The patient was treated properly and had a good outcome. The etiopathogenesis and the prognostic factors for this affection are not well established and are still being debated by authors. Further clinical data would contribute to a better understanding of this pathology in order to provide a better prognosis.

Pseudotumoral neuro-behcet's disease: case series and review of literature.

BACKGROUND: Behcet's disease (BD) is a multisystem autoimmune relapsing vasculitis with an almost unknown etiology involving both large and small vessels. The neurological involvement called neuro-Behcet's disease (NBD) is rare. NBD can be responsible for tumor-like masses mimicking low-grade gliomas in only a few cases. METHODS: We report here the main characteristics, treatment, and outcome of 43 patients (4 personal cases and 39 patients from the literature) with a pseudotumoral presentation of NBD (PT NBD). We compared our findings with those of the classical form of NBD. RESULTS: The median age was 35.86 (12-59 years) years, with a male predominance (67.4%). PT NBD was the inaugural of the disease in 51.2% of cases. The neurological manifestations included headache (n = 31), pyramidal syndrome (n = 28), cerebellar syndrome (n = 5), behavioral changes (n = 5), and pseudobulbar signs (n = 2). Ophthalmologic examination revealed papilledema in 3 cases. On cerebral imaging, the most affected regions of the brain were the capsulothalamic region (n = 15, 37.5%) and the brainstem (n = 14, 35). Histological analysis revealed necrotic lesions with perivascular inflammatory infiltrate without signs of tumoral or infectious lesions. Treatment consisted of corticosteroids (n = 40, 93%) and immunosuppressive agents (n = 28, 65.11%), leading to complete clinical and imaging remission in 41.5% of patients. CONCLUSION: PT NBD is a rare but life-threatening condition.

Hepatic myelopathy neurological complication of chronic liver disease: two case reports.

BACKGROUND: Hepatic myelopathy is a very rare neurological complication of chronic liver disease. Patients habitually present with progressive pure motor spastic paraparesis. This neurological dysfunction is almost always due to cirrhosis and portocaval shunt, either surgical or spontaneous. CASES REPORT: We report two cases of a 57-year-old man and a 37-year-old woman with progressive spastic paraparesis linked to cirrhosis and portal hypertension. The two patients are of Tunisian origin (north Africa). Magnetic resonance imaging of the spinal cord of two patients was normal, while brain magnetic resonance imaging showed a T2 hypersignals of the pallidums. These signs, in favor of hepatic encephalopathy in the two patients with cirrhosis with isolated progressive spastic paraparesis without bladder or sensory disorders, help to retain the diagnosis of hepatic myelopathy. CONCLUSION: Hepatic myelopathy is a severe and debilitating neurological complication of chronic liver disease. The pathogenesis is misunderstood and seems to be multifactorial, including the selective neurotoxic role both of ammonia and other pathogenic neurotoxins. Usually a pathological brain magnetic resonance imaging showing a hepatic encephalopathy was documented, contrasting with a normal spinal cord magnetic resonance imaging that contributed to diagnosis of hepatic myelopathy. Conservative therapies such as ammonia-lowering measures, diet supplementation, antispastic drugs, and endovascular shunt occlusion show little benefit in improving disease symptoms. Liver transplantation performed at early stage can prevent disease progression and could probably allow for recovery.

Prevalence of human herpesvirus U94/REP antibodies and DNA in Tunisian multiple sclerosis patients.

Human herpesvirus 6 (HHV-6) has been linked to the pathogenesis of multiple sclerosis (MS). Based on antibody detection and quantitative HHV-6 polymerase chain reaction assay, this study aimed to analyze the possible association between infection with HHV-6 and MS. A total of 131 serum samples were analyzed by ELISA for the presence of specific antibodies to HHV-6 latency-associated U94/REP protein: 68 serum samples from 60 MS patients (20 in relapse and 48 in remission phase) and 63 serum samples from 63 healthy controls. Real-time quantitative PCR for HHV-6 U94/rep DNA was also performed in total blood of MS patients and healthy controls. The serological analysis by ELISA showed that MS patients had increased prevalence and titers of anti-U94/REP immunoglobulins in comparison with control group (seroprevalence 51.47 % versus 28.57 % and mean titer of positive samples 1:248 versus 1:110; p=0.0005), with significant difference between relapse and remission phases. HHV-6 DNA was detected in 4 of 60 MS patients (6.66 %) and in 2 of 63 healthy controls (3.17 %), confirming previous data of prevalence obtained by qualitative nested PCR. However, viral load was higher in MS patients compared to controls, and differences were statistically significant (p=0.02). The results show that, in spite of the low presence of HHV-6 DNA in peripheral blood, MS patients have increased prevalence and titer of IgGs reacting with HHV-6 latency-associated U94/REP protein.

Identification of human herpesviruses 1 to 8 in Tunisian multiple sclerosis patients and healthy blood donors.

Members of the human Herpesviridae family are candidates for representing the macroenvironmental factors associated with multiple sclerosis (MS) pathogenesis. To verify the possible role of human herpesviruses (HHVs) as triggering or aggravating factors in relapsing-remitting multiple sclerosis clinical outcome, we studied the prevalence of all eight human herpesviruses in whole blood samples collected from 51 MS patients and from 51 healthy controls. The presence of DNA of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), varicella zoster virus (VZV), Epstein-Barr virus (EBV), human cytomegalovirus (HCMV), human herpesvirus 6 (HHV-6), human herpesvirus 7 (HHV-7) and human herpesvirus 8 (HHV-8) was searched by specific nested polymerase chain reaction. HHVs were significantly more prevalent in the blood of MS patients than in those of the controls (P < 10(-4)). HSV-1, HSV-2, HCMV and HHV-8 were negative in both MS patients and controls samples. In MS patients, EBV, HHV-7, HHV-6 and VZV were detected in 31.3%, 33.3%, 5.8% and 7.8% of samples, respectively, compared with 3.9%, 9.8%, 1.96% and 1.96%, respectively, of samples from controls. We found a statistically significant difference only for EBV DNA and for HHV-7 DNA prevalence (P < 0.001 and P = 0.03). Although these results indicate lack of apparent association in terms of gender, type of diagnosis, symptoms, disease score and ß interferon treatment between EBV or HHV-7 to MS among Tunisian patients, heterogeneity related to genetic polymorphism as well as geographical distribution of the disease and of pathogens may be of significance.

[Diagnostic strategy of metachromatic leukodystrophy in Tunisia]. / La leucodystrophie métachromatique : stratégie diagnostique en Tunisie.

We recruited a 44-year-old woman who had a dementia with behavioral and personality troubles. A biochemical analysis which includes a qualitative study of urinary sulfatides by thin layer chromatography followed by the determination of the enzymatic activity of arylsulfatase A (ARSA) was performed. The Molecular analysis concerned the research of the most frequent mutations (459 +1 G> A, p.P426L, p.I179S). The profile that has revealed the presence of 3-O-sulfogalactosylceramide fraction was in favor of metachromatic leukodystrophy. The activity of arylsulfatase A was collapsed in the index case which confirmed the phenotype of the adult form of the diagnosed MLD. The molecular study showed the presence of the mutation p.I179S in the homozygous state in the index case.

Association of the IL-10 receptor A536G (S138G) loss-of-function variant with multiple sclerosis in Tunisian patients.

Interleukin-10 (IL-10), a potent anti-inflammatory T-cell cytokine, has been shown to be a regulatory cytokine that is associated with disease remission in multiple sclerosis (MS) and exerts its activity through its cognate cell surface receptor complex, IL-10 receptor 1 (IL-10R1) and IL-10R2. The purpose of this study was to investigate the IL-10R1 S138G loss-of-function polymorphism (A536G: rs3135932) for possible influence on susceptibility and outcome of MS in Tunisian patients. A total of 103 Tunisian MS patients and 160 control subjects were studied. Genomic DNA samples were extracted from leukocytes and used to investigate S138G polymorphism in IL-10R1 gene by multiplex allele-specific polymerase chain reaction. Associations between G allele [odds ratio (OR) = 5.57; 95% confidence intervals (CI) = 3.26-9.54; p = 10-7 ], GG genotypes [OR = 10.41; 95% CI = 2.28-47.58; p = 0.0007] and AG genotype [OR = 4.14; 95% CI = 2.16-7.93; p = 0.000016] with the risk development of MS were found. In contrast, the AA genotype seemed to be associated with protection against MS [OR = 0.17; 95% CI = 0.09-0.30; p = 10-7 ]. No association was found between S138G SNP and clinical features or disease activity of MS patients. In conclusion, our results suggest that S138G loss-of-function polymorphism of the IL-10R1 may be important risk factor in increasing susceptibility to MS.

[Risk factors of mental disorders in epileptic patients: case-control study]. / Facteurs de risque des troubles mentaux chez les patients epileptiques: etude cas-temoins.

The aim of this study was to analyse the risk factors of mental disorders in epileptic patients. It was a case-control study concerning 200 epileptic out-patients examined in the department of Neurology of Monastir University Hospital during four months. Patients had been divided into two groups: the first (study-group) included 100 epileptic patients with mental disorders compared with a control-group of 100 epileptic patients without mental disorders. General seizures were significantly more frequent in the study-group (78%) than in the control-group (57%) (p=0,001). In the study-group, mental disorders were dominated by the behavioraland character disorders. Existence of temporal focus in electroencephalography or structural abnormality in tomodensitometry was more frequent in epileptic patients with mental disorders. The medium term course of epilepsy was significantly longer in the study-group (15.38 years versus 10?35 years; p=0.00007). Association of antiepileptic agents was significantly more frequent in study-group (38% versus 15%; p= 0,0002). However, no correlations were found between mental disorders and sex, age at onset of epileptic seizures and seizures frequency. The results of our study suggest that epilepsy characteristics and anti-epileptic treatment seem to be the principal factors of mental disorders in epileptic patients.

The association between functional HLA-G 14bp insertion/deletion and +3142 C>G polymorphisms and susceptibility to multiple sclerosis.

We aimed to investigate two main polymorphisms in the 3' untranslated region (3'UTR) of the HLA-G gene [14bp insertion/deletion (INS/DEL) and +3142 C>G] and to assess their impact on the soluble HLA-G (sHLA-G) production in patients with multiple sclerosis (MS). This study included 60 patients with relasping-remitting (RR) MS and 112 healthy donors (HD). Mutations were identified by PCR and PCR-RFLP, and serum sHLA-G quantification was performed by ELISA. For the 14bp INS/DEL polymorphism, variants frequencies were similar in patients and controls, whereas a significant increased frequency of the +3142 G allele was found in MS patients compared to HD (63.4% vs 52.3%, p=0.04; OR=1.58, 95%CI=1.003-2.48). In addition, an association was found between MS susceptibility and the haplotypes regrouping both studied polymorphisms. Indeed, the 14bp DEL/+3142 G haplotype frequency was significantly increased in MS patients compared to HD (20.8% vs 12.5%, p=0.04, OR=1.84). On the other hand, no associations were detected between both polymorphisms and clinical parameters, except the lower age of disease onset (ADO) in patients with the +3142 C/C genotype. Moreover, our study doesn't show any significant variation of sHLA-G serum levels between patients and controls. Our findings showed that the +3142 C>G, but not the 14bp INS/DEL, polymorphism may constitute a genetic susceptibility factor to MS in the Tunisian population. However, no association was found between the two polymorphisms and sHLA-G serum levels.

[Type 1 neurofibromatosis and epilepsy]. / Neurofibromatose de type 1 et epilepsie.

Epilepsy has been rarely reported with type 1 neurofibromatosis (Reckling Hausen disease). It may occur in 3 to 6% of cases. We report in this study three cases of patients with type 1 neurofibromatosis associated with epilepsy. The patients were respectively 23, 30 and 35 years old. Epilepsy was focal and complex in one patient, generalized in one case and simply focal in another one. Cerebral MRI showed sphenoidal dysplasia and temporal lobe ectopy compressing orbital structures in one patient and normal in the other cases. We discuss trough these three cases the relationship between Reckling Hausen disease and epilepsy.

[Posterior cerebral encephalopathy]. / Encephalopathie posterieure reversible.

Posterior reversible encephalopathy (PRE) is a recent syndrome characterized by headache, vomiting, seizures, visual loss, altered mental status with or without motor or sensitive deficit. Neuroimaging demonstrates symmetrical posterior cortical and subcortical lesions. The aetiology remains uncertain but vascular hypotheses is the most retained. We report a case of a 21 year old man with posterior cerebral encephalopathy, the toxic hypo these remains the most probable.

[Ischemic strokes in young adults]. / Accidents vasculaires cérébraux ischémiques du sujet jeune.

OBJECTIVES: The purpose of this study was to determine etiologies and outcome of strokes in young adults. PATIENTS AND METHODS: We studied retrospectively 48 cases of patients with transient ischemic attack or arterial ischemic stroke aged between 15 and 48 years admitted in the Neurology and Cardiology Departments of the University Hospital of Monastir from 1987 to 1996. The study variables included the full clinical spectrum, spanning historical, laboratory, radiological and outcome parameters. RESULTS: Thirty four were female and 14 male, the mean age was 33 +/- 8.8 years, with a peak in the 4th decade. Our series is characterised by the higher incidence of cardioembolic dominated by prosthetic valve. 62.5% of patients had common vascular risk factors. Non-atherosclerotic arteriopathies were observed in six cases uncommon etiologies of ischemic stroke (Moya-Moya disease, Takayasu's disease...). Etiology remain undetermined in four cases. Mortality rate was 8.5%. Reccurrences were observed in 12.5%. 29% of patients have recovered complete autonomy while 26% have conserved severe handicap. CONCLUSION: We found a higher incidence of cardioembolic diseases dominated by prosthetic valve.

Evaluation of the implication of KIR2DL2 receptor in multiple sclerosis and herpesvirus susceptibility.

To evaluate the possible effect of cell immunoglobulin-like receptors (KIRs) on viral infection in multiple sclerosis (MS) patients, we performed genotyping of KIR2DL2 and his HLA-C1 ligand and we analyzed the presence of all eight human herpesviruses (HHVs) in 60 MS patients and 112 healthy controls. Significantly higher frequencies were found for KIR2DL2 enhanced in the presence of its ligand HLA-C1 in MS patients. Moreover, a significant association was observed between an increase in HHV risk of infection in KIR2DL2 and HLA-C1 positive patient. Our results confirm a possible effect of KIR2DL2 on viral infection susceptibility in MS patients.

Seizures and movement disorders induced by hyperglycemia without ketosis in elderly.

BACKGROUND: Non-ketotic hyperglycemia (NKHG) may increase the probability of seizures and movement disorders. METHODS: We describe a series of 14 elders admitted for seizures and movement disorders linked to NKHG. RESULTS: Twelve patients developed motor seizures and two others movement disorders. Glucose levels varied 9.28 to 32 mmol/l, while osmolarity values varied from 302.28 to 328 mosmol/l. All patients responded well to insulin therapy and four of them needed anti-epileptic drugs. CONCLUSION: Seizures or movement disorders in elderly with NKHG could be misdiagnosed as neurological diseases. Blood glucose must be audited whenever patients with seizures or movement disorders are encountered, as the condition may quickly resolve when NKHG is controlled.

Cerebral Aneurysms: A Rare Feature of Behçet's Disease-A Case Report and Review of the Literature.

Behçet's disease (BD) is a multisystem vascular inflammatory disease with several clinical manifestations. Intracranial aneurysms are an extremely rare but nevertheless severe complication of BD. We report a case of a 44-year-old man. The diagnosis of BD was made based on the presence of recurrent oral aphthous ulcers and positive human leukocyte antigen (HLA-) B51 in the absence of evidence of other diseases. MRI showed an ancient ischemic right capsulolenticular lesion, subacute white matter hypersignals of the left capsule lenticular region, and multiple arterial aneurysms. The patient underwent two-month systemic high-dose corticosteroids and immunosuppressive therapy associated with severe neurological deficiency upon admission and severe impairment upon discharge. A thorough review of the literature showed 20 case reports of intracranial aneurysms in BD.

Brain MRI and biological diagnosis in five Tunisians MLD patients.

Metachromatic leukodystrophy (MLD) is a recessive autosomal disease which is characterized by an accumulation of sulfatides in the central and peripheral nervous system. It is due to the enzyme deficiency of the sulfatide sulfatase i.e. arylsulfatase A (ASA). we studied 5/200 cases of MLD and clearly distinguished three clinical forms. One of them presented the juvenile form; two presented the late infantile form; and two other presented the adult form. The Magnetic Resonance Imaging (MRI) of these patients showed a diffuse, bilateral and symmetrical demyelination. The biochemical diagnosis of MLD patients evidencing the low activity of ASA and sulfatide accumulation. PATIENTS AND METHODS: We studied 5/200 MLD patients addressed to us for behavioral abnormalities and progressive mental deterioration. All of them were diagnosed at first by brain MRI evidencing a bilateral demyelination, then the measurement of ASA activity using P-nitrocathecol sulfate as substrate, finally the sulfatiduria was performed using thin-layer chromatography using alpha-naphtol reagent. RESULTS: In this study, from 200 patients presenting behavioral abnormalities and a progressive mental deterioration, we reported just 2 patients were diagnosed as late-infantile form of MLD. Only1 case presented as the juvenile form; and 2 patients with the adult-type of MLD. The brain magnetic resonance imaging (MRI) of all patients showed characteristic lesions of MLD with extensive demyelination. Biochemical investigations of these patients detected a low level of ASA activity at 0°C and 37°C; the excess of sulfatide in sulfatiduria. CONCLUSION: MRI is required to orient the diagnosis of MLD patients; the latter must be confirmed by the biochemical investigations which is based on the measurement of ASA activity and the excess of sulfatide showed in the sulfatiduria. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here:http://www.diagnosticpathology.diagnomx.eu/vs/1791578262610232.