Cortico-juxtacortical involvement increases risk of epileptic seizures in multiple sclerosis

OBJECTIVES

Previous studies have reported an increased risk for epileptic seizures in multiple sclerosis (MS) patients. However, data on the pathogenesis of seizures remain inconclusive. The aim of our study is to evaluate prevalence, clinical and paraclinical features of epileptic attacks in our MS cohort and to search MS-specific risk factors for epileptic seizures.

MATERIALS AND METHODS

In this cohort of 428 MS patients, 13 patients were identified with epileptic seizures occurring at any point during the course of MS including at MS onset. As a control group, we selected 26 MS patients without seizures and matched for gender, age and date of MS onset. We compared demographic features and clinic-radiological findings between the both groups.

RESULTS

Thirteen patients (3%) were identified as having epileptic attacks. Ten patients (77%) experienced focal seizures, half of whom had confirmed secondary generalization. We did not find an association between seizures and disease course. Most patients had a single or few (2-5) seizures. MS patients with seizures had a significantly higher number of cortical and juxtacortical lesions on T2-weighted/fluid attenuation inversion recovery magnetic resonance imaging than control group [OR = 2.6 CI95% (1.0-6.5); P = 0.047].

CONCLUSIONS

Our findings support a credible role of cortical and juxtacortical involvement in the development of epileptic seizures in MS.

[Myasthenic crisis and Takotsubo syndrome: a non-chance relationship]

INTRODUCTION. Takotsubo syndrome (TTS) is a rare condition that mimics an acute myocardial infarction. It is associated with precordial pain, ST segment elevation, absence of coronary occlusion and reversible deformation of the left ventricle due to anteroapical dyskinesia that is reminiscent of a Japanese art of fishing octopuses (tako-tsubo). It is related with emotional and physical stress, and is thought to be mediated by an acute release of catecholamines. CASE REPORT. An 83-year-old woman with hypertension. She was admitted to the heart unit with a suspected acute coronary syndrome and respiratory failure, and thus required mechanical ventilation. An echocardiography scan showed severe ventricular dysfunction with apical dyskinesia. Cardiac catheterisation ruled out heart disease and a ventriculography scan revealed a bloated systolic deformation of the anterior and apical segments (TTS). Attempts to withdraw ventilation were unsuccessful and the neurology department was consulted. A directed medical history revealed that the patient had been suffering from generalised weakness, and progressive dysphagia and dyspnoea for several months. Results of an edrophonium test were positive. Single-fibre electromyography showed a pathological jitter and acetylcholine anti-receptor antibodies were positive. The patient was treated with immunoglobulins, corticoids and pyridostigmine. A control echocardiogram showed resolution of the TTS. CONCLUSIONS. TTS must be considered within the extra-neurological complications arising from myasthenic crisis. The neurologist must take this into account when faced with any symptom or sign of a potentially cardiac origin in myasthenic crisis and other neurocritical conditions.

Spasticity improvement in patients with relapsing-remitting multiple sclerosis switching from interferon-β to glatiramer acetate: the Escala Study

BACKGROUND

A recent pilot study suggested spasticity improvement during glatiramer acetate (GA) treatment in multiple sclerosis (MS) patients who previously received interferon-β (IFN-β).

OBJECTIVE

To evaluate changes in spasticity in MS patients switching from IFN-β to GA.

METHODS

Observational, multicentre study in patients with relapsing-remitting MS (RRMS) and spasticity switching from IFN-β to GA. The primary endpoint comprised changes on Penn Spasm Frequency Scale (PSFS), Modified Ashworth Scale (MAS), Adductor Tone Rating Scale (ATRS), and Global Pain Score (GPS) at months 3 and 6 after starting GA.

RESULTS

Sixty-eight evaluable patients were included (mean age,41.7±9.5 years; female,70.6%; mean time from MS diagnosis to starting GA,7.6±5.7 years). Previous treatments were subcutaneous IFN-β1a in 42.6% patients, intramuscular IFN-β1a in 41.2% and IFN-β1b in 32.4%, whose mean durations were 3.5±3.3, 2.7±2.5 and 4.4±3.6 years, respectively. Statistically significant reductions in mean scores on all spasticity measurements were observed from baseline to month 3 (PSFS, 1.7±0.9 vs 1.4±0.6, p<0.01; MAS, 0.7±0.5 vs 0.6±0.5, p<0.01; highest MAS score, 1.9±0.8 vs 1.7±0.8, p<0.01; ATRS, 1.6±0.6 vs 1.4±0.6, p<0.01; GPS, 29.4±22.1 vs 24.7±19.4, p<0.01) and from baseline to month 6 (PSFS, 1.7±0.9 vs 1.3±0.6, p<0.01; MAS, 0.7±0.5 vs 0.5±0.5, p<0.01; highest MAS score, 1.9±0.8 vs 1.5±0.9, p<0.01; ATRS, 1.6±0.6 vs 1.3±0.6, p<0.01; GPS, 29.4±22.1 vs 19.1±14.8, p<0.01).

CONCLUSION

Spasticity improvement in terms of spasm frequency, muscle tone and pain can be noted after three months and prolonged for six months of GA treatment.

[Pseudo-conduction block in nonsystemic vasculitic neuropathy]

SUMMARY

Introduction. Nonsystemic vasculitic neuropathy (NSVN) is an inflammatory disorder of the vasa nervorum which usually is expressed as a mononeuritis multiplex. We present a patient with NSVN with histological confirmination focused on the neurophysiological findings at the early stages.

CASE REPORT

A 36 years-old woman presented with paresthesia and weakness in her right hand followed by left footdrop. The first neurophysiologic examination showed low amplitude of the right median nerve (RMN) CMAP with proximal stimulation. A second examination showed signs of axonal damage in several nerves, including the RMN.

CONCLUSIONS

The acute ischemic damage of a nerve can give a pattern of conduction block in the electroneurographic study as in the RMN of the presented case. This phenomenon is referred as "pseudo-conduction block", since it is transient and evolves towards a definite pattern of axonal neuropathy. When a vasculitic neuropathy is suspected, repeated neurophysiologic studies are necessary in order to ensure a proper (appropriate) characterization of the lesional patterns.

[Rhombencephalitis caused by Listeria: clinical-radiological correlation]

Rhombencephalitis due to Listeria is a serious and infrequent infection of the brainstem. It principally affects subjects who were previously healthy. It shows itself clinically in two phases: the first with unspecific symptoms, which could last one week, and the second with the appearance of focal neurologic signs at the level of the brainstem. We present the case of a patient with rhombencephalitis due to Listeria that began initially with headache, nauseas and fever and after ten days the patient showed an asymmetrical affection of cranial nerves, cerebellar signs and sensory deficits in the left hemibody. Subsequently this became complicated with acute respiratory insufficiency, requiring admission to the Intensive Care Unit, and with episodes of urinary retention that required exploration. The early magnetic resonance image showed hypertense patch lesions that were objectified in T2 sequences at the level of the bulb and the pons. Facing a clinical-radiological suspicion of rombencephalitis due to Listeria, treatment was begun with ampicillin and tombramycin. After some days a positive haemoculture for Listeria monocytogenes serotype 4B resistant to ampicilin was detected, therefore it was replaced with vancomycin. The patient survived and on discharge he had oculomotor disorder and micturition problems as sequels. We would like to emphasise the importance of early recognition of the clinical signs of the disease and the early permormance of magnetic resonance, with diagnostic support, to be able to start a suitable antibiotic treatment as quickly as possible.

[Internal carotid stenosis and giant cell arteritis]

We report on the case of a 69-year-old man admitted with a transient ischemic attack preceded by a two months history of severe headache. Giant cell arteritis was diagnosed by means of temporal artery biopsy. Angiography showed an intra- and extracranial stenosis of the left internal carotid artery. The possible relationship between this stenosis and vasculitis is discussed and stroke as a clinical manifestation of the giant cell arteritis is reviewed.

Acute carotid obliteration: a new vascular manifestation in POEMS syndrome

The case of a 65-year-old woman with polyneuropathy, organomegaly, skin changes and monoclonal gammopathy of IgG-lambda type is described. This patient developed an acute carotid obliteration during oral anticoagulation and despite absence of vascular risk factors. Macroangiopathy has been described as a rare systemic manifestation of POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal spike and skin changes), affecting the coronary and lower limbs arteries. To our knowledge, this is the second case of POEMS syndrome with a cerebrovascular manifestation.

[Variation of Mini-Mental-State examination scores due to age and educational level. Normalized data in the population over 70 years of age in Pamplona]

The Mini-Mental-State Examination (MMSE) is widely used as a screening tool for dementia in epidemiological studies. Its applicability in population-based studies is nevertheless limited by its low specificity. The effect of age and educational level have been usually ignored when cut-off scores have been selected. The aim of this study was to evaluate the effect of age and educational level on the MMSE scores in a representative sample of subjects older than 70 and provide adjusted normalised data according to these two variables, after excluding subjects with dementia or cognitive decline. Population-based, cross-sectional and longitudinal study of a representative cohort of 1367 subjects older than 70. All subjects with suspected dementia or cognitive decline received a neurological evaluation where clinical and etiological diagnosis were established. Normal MMSE scores, as defined by the 10th percentile, varied significantly across age and educational level groups. Exclusion of demented or cognitively declined patients from the reference population reduced the variability and "range of normality", but this remained excessively high in the older and less educated groups. The use of different cut-off points for each age and educational level groups may improve the specificity and applicability of the MMSE in population-based epidemiological studies. However, the wide amplitude of the range of normality suggests that different approaches, other than this vibariate analysis, may prove more adequate in the selection of cut-off scores for the MMSE.

Bilateral pallidostriatal necrosis caused by a wasp sting: a clinical and pathological study

A previously healthy man developed an acute encephalopathy with coma after a single wasp sting on his chin. Brain CT showed bilateral pallidostriatal radio-lucencies. He died 72 hours after the sting with no evidence of primary cardiorespiratory failure or allergic reaction. Pathological findings were bilateral pallidostriatal necrosis and diffuse neuronal damage in the frontal, temporal, and parietal cortex. The neurotoxic effect of the poison, together with a hypersensitivity are the most likely explanations for this unusual encephalopathy.

Prevalence of Alzheimer's disease and other dementing disorders in Pamplona, Spain

We investigated the prevalence of dementing disorders in the city of Pamplona, Spain, using a door-to-door two-phase approach. We first administered the Cambridge Examination of Mental Disorders of the Elderly (CAMDEX) to all survivors, as of March 1, 1991, of a probability sample of the total population identified in 1989 (n = 1,127). Using specified diagnostic criteria, the study neurologists extensively investigated those subjects who screened positive on CAMDEX. We found 194 subjects affected by dementia, 119 had Alzheimer's disease; 51 vascular or mixed dementia, and 16 secondary dementia. The prevalence of both dementia and Alzheimer's disease increased steeply with advancing age and was consistently higher in women. The prevalence of combined vascular and mixed dementia increased less rapidly with age, and was generally higher in men. Alzheimer's disease was the most common type of dementia. Our prevalence figures for dementia and Alzheimer's disease are similar to those previously reported in Europe.

Temporal discrimination is abnormal in Parkinson's disease

Temporal discrimination thresholds (TDT) for recognition of paired sensory (tactile, auditory and visual) stimuli given over a wide range of time intervals were assessed in 44 patients with Parkinson's disease (PD) and 20 age-matched normal subjects. A significant increment in TDT for all three sensory modalities was found in PD patients compared with controls. This abnormality was greatly attenuated for about 2 h by a single levodopa/carbidopa (250/25 mg) tablet. A significant correlation was found between disease severity as assessed clinically and TDT. Patients with more severe PD had higher TDT values. The study of the peripheral median nerve and cortical somatosensory evoked potential recovery curves following double electrical stimulation of the index finger showed no differences between patients and control subjects, nor changes from 'off' to 'on' motor state which could explain the findings. These results indicate the existence of an abnormality of timing mechanisms in PD.

The anatomical basis of somaesthetic temporal discrimination in humans

Somaesthetic temporal discrimination (STD) is the ability to perceive as separate two successive somaesthetic stimuli applied to the same or different parts of the body. Paired electrical stimuli were applied to the index finger, using different time-intervals, to study the STD threshold (STDT) in 84 normal subjects and 51 patients with focal cerebral lesions. Abnormal STDT values were found on the affected side of patients with a lesion of the primary somatosensory cortex, and internal capsulethalamus. Lesions which did not produce sensory impairment but caused abnormal STDT were located in the posterior parietal cortex, the head of the caudate nucleus, the putamen, the medial thalamus and the lenticular nucleus. Frontal, temporal and occipital cortex lesions did not produce any abnormality in the STDT, but one patient with a bilateral lesion of the supplementary motor area (SMA) had abnormal STDT. These results indicate that normal perception of two somaesthetic stimuli as separate in time depends not only upon the integrity of the somatosensory pathway and primary somaesthetic cortex, but also of the posterior parietal cortex, SMA and subcortical structures such as the striatum and thalamus.

[Brain photon emission tomography. Value of the corticocerebellar index and gammagraphic patterns in Alzheimer's disease and other diseases]

Brain single photon emission computed tomography (SPECT) with 99mTc-HMPAO is a diagnostic tool for evaluating regional cerebral blood flow. Recently, the diagnostic possibilities of the method are being investigated in some neurologic disorders, such as cerebrovascular accidents, seizures and dementia. This work has been carried out with 54 subjects, 9 healthy volunteers and 45 patients (31 dementia and 14 epileptics), in order to evaluate gammagraphic patterns and the utility of cortico/cerebellar activity indexes. An interesting diagnostic finding is a significant decrease (p less than 0.001) in perfusion of temporoparietal regions in the patients with Alzheimer's disease in relation with the healthy volunteers' group. We have not found significant changes in perfusion in the group of epileptic patients during the interictal phase. We conclude emphasizing the interest of the SPECT in the differential diagnosis of dementia.