[Acute demyelinating motor neuropathy: an atypical form of the Guillain-Barre syndrome?]

A 33-year-old man presented an acute motor demyelinating neuropathy following Campylobacter jejuni enteritis. The patient was improved with an IgIV treatment. Clinical features and course time were compatible with the diagnosis of a Guillain-Barré syndrome. The electrophysiologic studies were in favor of multifocal motor neuropathy with conduction blocks. We discuss the nosologic group of this neuropathy.

High prevalence of CACNA1A truncations and broader clinical spectrum in episodic ataxia type 2

OBJECTIVE

To characterize the nature of CACNA1A mutations in episodic ataxia type 2 (EA2), to search for mutations in sporadic cases, and to delineate better the clinical spectrum.

BACKGROUND

EA2 is an autosomal dominant disorder characterized by recurrent acetazolamide-responsive attacks of cerebellar ataxia. The mutated gene, CACNA1A, located on chromosome 19, encodes the alpha1A subunit of a voltage-dependent calcium channel. So far, only three CACNA1A mutations have been identified-in two EA2 families and in one sporadic case. These three mutations disrupted the reading frame and led to truncated proteins. Interestingly, distinct types of CACNA1A mutations have been identified in familial hemiplegic migraine (missense mutations) and spinocerebellar ataxia type 6 (SCA-6) progressive cerebellar ataxia (expanded CAG repeats). However, except for SCA-6, these genotype-phenotype correlations relied on the analysis of very few families.

METHODS

To characterize CACNA1A mutations, eight familial and seven sporadic EA2 patients were selected. All 47 exons of CACNA1A were screened by a combination of single-strand conformer polymorphism and sequencing analysis. In addition, the length of the CAG repeat has been determined in all patients.

RESULTS

Seven new mutations were detected in four multiple case families and three sporadic cases. Six of them lead most likely to truncated or aberrant proteins. CAG repeat sizes were in the normal range.

CONCLUSION

These data clearly establish the specificity of EA2 mutations compared with SCA-6 and familial hemiplegic migraine. Detailed clinical analysis of the mutation carriers showed the highly variable penetrance and expression of this disorder: Several of the carriers did not show any clinical symptom; others displayed atypical or permanent neurologic symptoms (such as recurrent, transient diplopia or severe, permanent, and isolated cerebellar ataxia).

Neuropsychologic and adaptive functioning in adolescents and young adults shunted for congenital hydrocephalus

The major aim of this study was to assess whether the syndrome of nonverbal learning disabilities described in hydrocephalic children is observed in adulthood. Eleven adults shunted for congenital hydrocephalus related to spina bifida and eight adults shunted for hydrocephalus related to aqueductal stenosis were administered an extensive neuropsychologic battery to investigate discrepancies between verbal and visuospatial cognition, verbal and visuospatial long-term memory, and psycho-social adaptive abilities. The results showed no discrepancies between Wechsler Performance IQ or Verbal IQ in either hydrocephalic group. Nevertheless, the subjects with spina bifida appeared more cognitively impaired than the subjects with aqueductal stenosis, who performed normally on the Wechsler Adult Intelligence Scale-Revised. Memory assessment using Signoret's Memory Battery revealed no discrepancy between verbal and visuospatial memory in the hydrocephalic group. Nevertheless, the subjects with spina bifida had poorer verbal and visuospatial memory performance than the subjects with aqueductal stenosis. There were no differences on the Vineland Adaptive Behavioral Scale between subjects with spina bifida and those with aqueductal stenosis in autonomy, socialization, and daily living skills. These results suggest that shunted congenital hydrocephalus is not characterized by nonverbal learning disabilities syndrome in adolescence or in adulthood.

Effects of the method of drawing regions of interest on the differential diagnosis of extrapyramidal syndromes using 123I-iodolisuride SPET

Various parameters are currently used for the semi-quantitative assessment of dopamine D2 receptors and differ according to the delineation of the striatal region of interest (ROI) and the choice of the reference ROI. The aim of this study was to assess the value of different ROI approaches in differentiating patients with normal or increased numbers of D2 dopamine receptors (group 1 = Parkinson's disease, n = 8) from patients with decreased dopamine D2 receptors (group 2 = other extrapyramidal syndromes, n = 9) using 123I-iodolisuride SPET (ILIS-SPET). 123I-iodolisuride (190 +/- 31 MBq) and 99Tcm-ethyl cysteinate dimer (99Tcm-ECD) perfusion SPET were performed in the same position, with a dual-headed gamera camera equipped with fan beam collimators. Both a geometric approach (ellipse, circle or rectangle) and an anatomical approach using the CT scan and perfusion SPET as anatomical guides were used to draw striatal and reference ROIs. A total of 33 different parameters were calculated for each patient, indicating the ratio of counts between the striatal and reference ROIs (frontal, occipital cortex or cerebellum) and the asymmetry between the right and left striatum. More significant differences between group 1 and group 2 were found by using geometric ROIs than by using anatomical ROIs. The most discriminant ratios were the caudate/occipital, caudate/frontal and striatum/occipital ratios (P = 0.001, P = 0.002, P = 0.003 respectively). A close correlation was found between the striatum/caudate and striatum/occipital ratios, but not between the striatum/frontal and striatum/occipital ratios or between the striatum/frontal and striatum/caudate ratios. We conclude that the occipital cortex is the best reference for the semi-quantitative evaluation of dopamine D2 receptors as the frontal cortex could include some dopamine D2 receptor-bound radioligand, and that the caudate/occipital ratio is an appropriate parameter for differentiating Parkinson's disease from non-Parkinson extrapyramidal syndrome by 123I-iodolisuride SPET.

[Anticonvulsants can aggravate idiopathic generalized epilepsy]

Antiepileptic drugs can sometimes worsen idiopathic generalized epilepsies. Relevant data are based on empirical experience of epileptologists and on few published case-reports according to the suspected drug with serious methodological limitations. Some animal models of epileptic syndromes such as genetic models of absence seizures in rat seem to be helpful for understanding the possible mechanisms underlying drug-induced syndrome aggravation. Adequate epileptic syndrome diagnosis is needed before starting antiepileptic drug.

Bilateral olivary hypertrophy and palatal myoclonus

We report on a case of palatal myoclonus associated with olivary hypertrophy on magnetic resonance imaging (MRI) in a 63-year-old man. This rare radiological finding must be differentiated from a brainstem tumor.

[Equilibrium disorders and neuropathy associated with serum anti-Mag activity]

We report the case of a 65 year-old man with a dysglobulinemic neuropathy associated with anti-Mag antibodies. Central (cerebellar) or peripheric (proprioceptive) origin of the gate disorder are discussed.

[Indications for emergency EEG. Focal neurologic deficits and partial epileptic seizures in adults]

A focal neurological deficit is defined as the clinical expression of a structural or functional, transient or permanent abnormality that can be ascribed to a particular brain region. In that context, the indications of an EEG as part of the emergency management may be summarized as follows: i) The EEG in not indicated for the diagnostic, prognostic or therapeutic management of transient ischemic attacks (TIA) or migraine; ii) The possible prognostic value of EEG during the acute phase of stroke has not yet been validated; iii) In partial epileptic seizures, especially complex partial epilepsy, the EEG is useful but not always indispensable for diagnosis. Its therapeutical and prognostic implications are still uncertain. Lastly, EEG is an absolute indication as part of the emergency management of focal deficits in a febrile context, where its diagnostic and prognostic value are unequaled.

[Cerebral achromatopsia without prosopagnosia, alexia, object agnosia]

A 62-year-old woman was admitted for a disorder of color vision. This cerebral achromatopsia was isolated, without prosopagnosia, alexia, object agnosia. MRI showed bilateral temporo-occipital infarcts, including lingual and fusiform gyrus. Neuropsychological examination and topographic hypotheses are discussed.

Sleep and the epilepsies

To review the numerous works concerning sleep and epilepsy, this review considers the effects of sleep, firstly on seizures and secondly on paroxysmal interictal EEG activity (PA), in the different types of epilepsy according to the International League against Epilepsy classification. Apart from the exceptions of the definite nocturnal preponderance of seizures in idiopathic rolandic epilepsy and of the mostly nocturnal occurrence of seizures in some types of familial or sporadic frontal-lobe epilepsy, assessing a seizure according to the time of day it occurs is of no diagnostic or predictive value. In generalised idiopathic epilepsy, as in partial symptomatic or cryptogenic epilepsy, only about 20% of the patients had a sleep increase in PA. This percentage is higher (75%) in idiopathic partial epilepsy. Stereoelectroencephalography demonstrates a relative stability of spiking within the focus across the states of vigilance and an increase in transmitted discharges during stages 3 and 4. In the Landau and Kleffner syndrome, as in the syndromes of continuous spike-waves during sleep, there is a huge, unexplained increase in PA during sleep. The neuropsychological consequences of this PA have some relationship with their localisation and the patient's age at the time of occurrence. Sleep PA has also been reported in several groups of non-epileptic subjects. As regards the effect of epilepsy on sleep, sleep may be lighter and abnormally discontinuous in the absence of seizures, particularly in temporal-lobe epilepsy.

[Paraneoplastic encephalomyeloneuritis with anti-Hu antibodies and cancer of the rectum]

We report the case of a 62-year-old man affected by anti-Hu-associated paraneoplastic encephalomyelitis. The underlying tumor was a neuroendocrine cancer of the rectum expressing Hu antigen. The neurologic presentation was limited to moderate sensitive neuropathy associated with two complex partial seizures (dreamy state) without any further signs of limbic encephalopathy. A paraneoplastic etiology should be considered in patients with moderate symptomatology. Paraneoplastic encephalomyelitis with anti-Hu antibodies is not always associated with small-cell lung cancer.

Paraneoplastic opsoclonus associated with cancer of the gall bladder

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[Treatment of juvenile myoclonic epilepsy with low-dose sodium valproate]

Eleven patients with Juvenile Myoclonic Epilepsy were treated using small doses of a sustained-release form of valproic acid (500 mg/day). This treatment has lasted for an average of 33 months (8-69) and has been continued in all of the patients. None of them has experienced a new generalized tonic-clonic seizure. The myoclonias have become considerably less frequent and less intense. No side-effects have been spontaneously reported by the group of patients. Thus, we suggest to start newly diagnosed patients on small doses of valproic acid.

Migraine and angina pectoris by coronary artery spasm

A migrainous patient who experienced chest pain attributed to angina pectoris by coronary artery spasm during a migraine attack is reported. Previous reports have already mentioned the association of these two conditions and suggested that it might be the manifestation of a generalized vasospastic disorder. This new report offers an opportunity to review and discuss the available data on such an association.

Study of unilateral hemisphere performance in children with developmental dysphasia

Hemisphere specialization for language was studied in 10 children with expressive developmental dysphasia (DD) (mean age 10 years 4 months) submitted to a dichotic listening task (in a word free-recall task and forced-attention task) and a finger tapping/vocalization dual-task paradigm. A nonsense shape dichaptic task was also introduced to control right hemispheric processing. Performances of dysphasic children were compared to those obtained from 15 normal children. The results showed that controls had a right ear advantage in free-recall (words) dichotic listening task and a significant right ear advantage in forced-right-attention task, with a change in ear asymmetry as a consequence of instruction. In the dysphasic group we observed a significant right ear advantage in the free-recall dichotic listening task and no change in ear asymmetry during forced right or forced left condition. Results in time sharing paradigm and nonsense dichaptic task are more difficult to interpret, because there was no interaction between group and condition. These results cannot support a complete left hemisphere dysfunction in developmental dysphasia.