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.

Stroke disclosing primary aldosteronism: Report on three cases and review of the literature

OBJECTIVES

There is a growing evidence of increased risk of cerebrovascular events in primary aldosteronism (PA). Nevertheless, acute neurologic ailment as presenting feature of PA is uncommon. Our aim is to highlight the diagnosis challenges in stroke unmasking PA and to discuss the underlying physiopathology and management dilemmas.

MATERIALS AND METHODS

We hereby describe three consecutive rare cases of stroke revealing PA. All patients had brain imaging and thorough biological and morphological assessment to rule out other etiologies of stroke. The diagnosis of primary aldosteronism was established according to the Endocrine Society Clinical Practice Guideline, with a review of the literature on the spectrum of neurologic manifestations in PA.

RESULTS

We report on three cases, two women and a man, presenting with ischemic or hemorrhagic stroke, of early onset in two of them. All of the reported patients had hypertension and hypokaliemia. This association prompted the assessment of renin angiotensin aldosterone system (RAAS) disclosing PA, which was due to bilateral adenomas in the first one or bilateral adrenal hyperplasia in the two others. All patients refused the surgical option and received spironolactone with recurrence of stroke in one of them due to treatment incompliance.

CONCLUSION

Although cerebrovascular events are quite common in PA, their occurrence as initial feature can be misleading. The association of hypokaliemia and refractory hypertension in ischemic or hemorrhagic strokes should prompt an assessment of the RAAS to rule out PA and initiate adequate management as soon as possible in order to avoid further complications.

Association between an angiotensin-converting enzyme gene polymorphism and Alzheimer's disease in a Tunisian population

BACKGROUND

The angiotensin-converting enzyme gene (ACE) insertion/deletion (I/D or indel) polymorphism has long been linked to Alzheimer's disease (AD), but the interpretation of established data remains controversial. The aim of this study was to determine whether the angiotensin-converting enzyme is associated with the risk of Alzheimer's disease in Tunisian patients.

METHODS

We analyzed the genotype and allele frequency distribution of the ACE I/D gene polymorphism in 60 Tunisian AD patients and 120 healthy controls.

RESULTS

There is a significantly increased risk of AD in carriers of the D/D genotype (51.67% in patients vs. 31.67% in controls; p = .008, OR = 2.32). The D allele was also more frequently found in patients compared with controls (71.67% vs. 56.25%; p = .003, OR = 2.0). Moreover, as assessed by the Mini-Mental State Examination, patient D/D carriers were more frequently found to score in the severe category of dementia (65%) as compared to the moderate category (32%) or mild category (3%).

CONCLUSIONS

The D/D genotype and D allele of the ACE I/D polymorphism were associated with an increased risk in the development of AD in a Tunisian population. Furthermore, at the time of patient evaluation (average age 75 years), patients suffering with severe dementia were found predominantly in D/D carriers and, conversely, the D/D genotype and D allele were more frequently found in AD patients with severe dementia. These preliminary exploratory results should be confirmed in larger studies and further work is required to explore and interpret possible alternative findings in diverse populations.

Recurrent status epilepticus in posterior reversible encephalopathy syndrome as initial feature of pediatric lupus: A newly diagnosed case and literature review

INTRODUCTION

Posterior reversible encephalopathy syndrome (PRES) is a recently described clinico-neuroradiological syndrome with several predisposing conditions. Systemic lupus erythematosus (SLE), beginning in 15-20% in childhood, is considered as a potential underlying etiology of PRES. In children, status epilepticus (SE) rarely complicates PRES, and exceptionally occurs in SLE.

METHODS

We report on an illustrative case of PRES complicating pediatric lupus revealed by recurrent SE, and we further review through a Pubmed search the previously reported cases of pediatric SLE, PRES and SE.

RESULTS

We describe the case of a 12-year old girl who presented with recurrent status epilepticus associated to high blood pressure and renal involvement. Brain imaging showed classical aspects of PRES. Immunological tests including antinuclear, anti-DNA, and anticardiolipin antibodies were positive. The diagnosis of SLE was established. The Pubmed search identified a total number of 9 children with SE in SLE, and 26 with PRES, including our patient.

CONCLUSIONS

We discussed the clinical and paraclinical features of PRES in SLE with epilepsy, their underlying pathophysiological aspects, and their management challenges. PRES should be considered in initial recurrent SE in children, justifying a battery of tests comprising immunological testing. Anticardiolipin antibodies seem to play a crucial role in epilepsy, PRES and renal involvement in pediatric SLE. Further studies are needed to clarify whether PRES should be considered one of the neuropsychiatric manifestations of SLE or a consequence of active disease in other organ systems or its treatment.

[Neurologic manifestations of sarcoidosis: A study of 18 cases]

INTRODUCTION

Sarcoidosis is a multisystemic granulomatous disease of unknown aetiology. Neurologic manifestations are found in 5 to 10% of cases.

PATIENTS AND METHODS

We conducted a retrospective study over 6-year period including 18 patients diagnosed with neurosarcoidosis in the Neurologic department of the Military Hospital of Instruction of Tunis. Clinical, radiological, therapeutic features and outcome were studied.

RESULTS

The mean age was 43.44 years. Neurologic signs were the first symptom in 10 cases. Peripheral nervous system impairment was often found. Meningitis was noted in 8 cases. Biological tests are not contributive for the diagnosis. The brain magnetic resonance imaging was pathologic in 10 cases. Corticosteroids were administrated in the majority of cases. Eight patients did not show any sign of improvement. Ten cases improved with treatment.

DISCUSSION AND CONCLUSION

Diagnosis of neurosarcoidosis is difficult because of its clinical and radiological polymorphism. It is based on a clinical history suggestive of neurosarcoidosis, laboratory, imaging and histological studies.

Limbic encephalitis associated with leucine-rich glioma-inactivated 1 antibodies

We describe the case of a patient with confirmed limbic encephalitis associated with leucine-rich glioma-inactivated 1 (LGI1) antibodies. A 59-year-old man presented to the Department of Neurology with bizarre behavior, memory loss, cognitive impairment, visual hallucinations, and myoclonus and facio-brachial dystonic seizures. A brain magnetic resonance imaging (MRI) revealed no hippocampal lesions. Blood tests showed hyponatremia. An electroencephalogram showed disorganization and slowing of background activity. Antiepileptic drugs were ineffective. The patient exhibited considerable improvement following immunotherapy. The diagnosis of limbic encephalitis associated with LGI1 antibodies should be considered in patients with clinical manifestations mimicking psychiatric disorders and in cases of refractory epilepsy especially with faciobrachial dystonic seizures. There is frequently hyponatremia, and cerebral MRI may be normal. Full recovery can be expected with early diagnosis and prompt treatment.

Clinical features and disability progression in multiple sclerosis in Tunisia: do we really have a more aggressive disease course?

BACKGROUND

Few epidemiological data are available on multiple sclerosis (MS) patients in North Africa (NA). Studies of immigrants from NA showed a more aggressive course compared to European patients.

OBJECTIVE

The aim of this study is to describe clinical and long term course characteristics of MS in Tunisia and to compare it to European cohorts.

METHOD

A total of 437 MS patients from three hospital based cohorts in Tunisia and having prospective follow up between 2010 and 2012 were analyzed. We considered as endpoints the time to reach EDSS scores of 3, 4 and 6 in the different clinical forms of MS and the beginning of a secondary progressive (SP) phase.

RESULTS

Sex ratio was 2.34. Mean age of onset was 30.3 years. The course was relapsing-remitting (RR) in 91% of patients and primary progressive (PP) in 9%. The most frequent isolated onset symptoms were respectively motor (28%), optic neuritis (20%) and sensory (16%) dysfunction. Median time to SP onset was 19.1 years. Median times from onset of multiple sclerosis to assignment of a score of 3, 4 and 6 were 8, 10.7 and 15 years respectively. Benign form of MS represented 31.5%. Median interval from the onset of the disease to EDSS score of 3, 4 and 6 was shorter in PP-MS than in RR-MS. However, there was no difference between these two groups for the median time from the assignment of EDSS 4 to the assignment EDSS 6.

CONCLUSIONS

Our study shows that Tunisian MS patients have a quite similar clinical feature to European patients. Still, larger MS multicenter cohort studies in NA with longer follow-up duration could clearly respond to the issue.

Cerebral venous thrombosis: clinical features, risk factors, and long-term outcome in a Tunisian cohort

BACKGROUND

Data from African countries regarding diagnosis, prognosis, management, and outcome of patients with cerebral venous thrombosis (CVT) are limited. The aim of the present study is to characterize clinical presentation, predisposing factors, neuroimaging findings, and outcomes of the disease in the Tunisian population.

METHODS

This is a prospective study including patients referred to the Neurology Department of the Military Hospital of Tunis between January 2009 and December 2012. The diagnosis of CVT was confirmed in all patients using magnetic resonance imaging and magnetic resonance venography. The demographic, clinical, radiological, and outcome data were recorded and analyzed. Median follow-up was 16 months (range 6 months to 4 years). Primary outcome was death or dependency as assessed by modified Rankin score more than 2 at the end of follow-up.

RESULTS

This study included 41 patients with CVT. Mean age was 41.24 years, predominantly women (68%). The mode of onset was acute in 10 patients (24%), subacute in 26 (64%), and chronic in 5 (12%). The most common presenting features were headache, observed in 83% of the patients, followed by seizures, focal motor deficits, papilledema, and mental status changes. Lateral (56%) and superior longitudinal (51%) sinuses were the most commonly involved. Multiple sinuses were involved in 46% of cases. Nineteen patients (46%) had a D-dimer level more than 500 ng/mL. Major causes of CVT were thrombophilia (56%), either genetic or acquired, obstetric and gynecological (50%), and septic (34%). Outcome was favorable in 83% of patients. At the end of follow-up, 32 patients (78%) had complete recovery (modified Rankin Scale [mRs] score 0-1), 2 (5%) had partial recovery (mRs score 2), and 4 (10%) were dependent (mRs score 3-5). One patient (2.5%) had a recurrent sinus thrombosis.

CONCLUSIONS

Our Tunisian population presented distinct risk factors profile with high frequency of thrombophilia, infections, and postpartum state. Oral contraceptive use is not a major risk factor in our population. The overall prognosis was good.

Methylenetetrahydrofolate reductase (C677T and A1298C) polymorphisms, hyperhomocysteinemia, and ischemic stroke in Tunisian patients

OBJECTIVE

The present study evaluated the role of the methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C gene polymorphisms and correlated these results with plasma homocysteine (Hcy) levels in Tunisian ischemic stroke (IS) patients.

METHODS

Overall, 84 patients with IS were included and compared with 100 healthy controls. The most common stroke risk factors were investigated. Fasting plasma Hcy levels were measured. Genotyping of the MTHFR C677T and A1298 polymorphisms was studied by polymerase chain reaction.

RESULTS

Aside from tobacco and alcohol use, the other studied factors were significant risk factors for IS. Mean plasma Hcy levels were significantly higher in IS patients than in controls (16.1 ± 8.28 μmol/L versus 8.76 ± 3.48 μmol/L, P < 10(-3)). Significant associations were found with both the MTHFR 677(CT + TT) and 1298 (AC + CC) genotypes in comparison with controls (P < 10(-3)). A significant synergistic interaction was also found with the double heterozygote MTHFR 677CT/1298AC (P < 10(-3)). Homocysteine levels were significantly higher in IS patients with the MTHFR C677T variant (CT and TT genotypes) (P < 10(-3)); however, the difference was not significant with the MTHFR A1298C variant (AC and CC genotypes) (P = .31).

CONCLUSION

The MTHFR C677T and A1298 polymorphisms (individually or in concert) and hyperhomocysteinemia represent important risk factors for IS. Elevated Hcy levels were found to be associated with the MTHFR C677T variant; however, no significant association was found with the MTHFR A1298C variant.