Non-epileptic seizures: delayed diagnosis in patients presenting with electroencephalographic (EEG) or clinical signs of epileptic seizures.

The clinical differentiation between epileptic seizures (ES) and non-epileptic seizures (NES) is often difficult and mostly based on the presence or absence of widely recognized features of ES such as tongue biting, falling, incontinence or concomitant epileptic abnormalities in the electroencephalogram (EEG). We retrospectively analysed the records of all patients referred to our Epilepsy Centre for refractory epilepsy and finally diagnosed with NES between 1980 and 1999 ( n= 103), half of them also exhibiting ES. The mean time-lapse between first attack and NES diagnosis was 8.7 +/- 1.3 years and 16.5 +/- 1.4 years for the NES and NES + ES groups respectively. At least one of the usual signs associated with generalized tonic-clonic seizures (tongue biting, falling or incontinence) was reported by 66% and 60% of patients with NES or NES + ES respectively. Interictal EEG abnormalities were recorded in 16% of NES patients vs. 80% of NES + ES patients. In the NES group, delay before establishing the correct diagnosis was significantly longer when the patients exhibited > or =1 symptom(s) of generalized seizures, or when patients exhibited interictal EEG abnormalities. Upon admission, 72% of NES patients and all NES + ES patients were being treated with antiepileptic drugs (AEDs).We conclude that EEG or clinical abnormalities suggestive of epileptic seizures are common in undiagnosed NES patients. Such diagnostic pitfalls, besides considerably delaying NES diagnosis, also considerably delay appropriate treatment implementation.

A gene on chromosome 11q23 coding for a putative glucose- 6-phosphate translocase is mutated in glycogen-storage disease types Ib and Ic.

Glycogen-storage diseases type I (GSD type I) are due to a deficiency in glucose-6-phosphatase, an enzymatic system present in the endoplasmic reticulum that plays a crucial role in blood glucose homeostasis. Unlike GSD type Ia, types Ib and Ic are not due to mutations in the phosphohydrolase gene and are clinically characterized by the presence of associated neutropenia and neutrophil dysfunction. Biochemical evidence indicates the presence of a defect in glucose-6-phosphate (GSD type Ib) or inorganic phosphate (Pi) (GSD type Ic) transport in the microsomes. We have recently cloned a cDNA encoding a putative glucose-6-phosphate translocase. We have now localized the corresponding gene on chromosome 11q23, the region where GSD types Ib and Ic have been mapped. Using SSCP analysis and sequencing, we have screened this gene, for mutations in genomic DNA, from patients from 22 different families who have GSD types Ib and Ic. Of 20 mutations found, 11 result in truncated proteins that are probably nonfunctional. Most other mutations result in substitutions of conserved or semiconserved residues. The two most common mutations (Gly339Cys and 1211-1212 delCT) together constitute approximately 40% of the disease alleles. The fact that the same mutations are found in GSD types Ib and Ic could indicate either that Pi and glucose-6-phosphate are transported in microsomes by the same transporter or that the biochemical assays used to differentiate Pi and glucose-6-phosphate transport defects are not reliable.

[Bradycardia: an unrecognized complication of some epileptic crises]. / La bradycardie: une complication méconnue de certaines crises épileptiques.

A 36-year-old man, treated for epilepsy since early childhood, was hospitalized for nocturnal paroxysmal disorders. The EEG-EKG-video monitoring revealed complex partial seizures with bradycardia secondary to a sino-auricular block. The occurrence of autonomic disturbances during seizures is well known, mostly described in temporal epilepsy. Ictal bradycardia, with asystole, has been unfrequently reported, while tachycardia appears more common. A systematic investigation of cardiac data synchronized with EEG recordings, especially in case of aspecific fainting, could give a more accurate diagnosis and treatment, and so reducing sudden unexplained death in epileptic patients.

[Acute encephalomyopathy and persistent cerebellar syndrome after lithium salt and haloperidol poisoning]. / Encéphalomyopathie aiguë et syndrome cérébelleux persistant après intoxication par sel de lithium et halopéridol.

A 44-year-old maniacodepressive woman developed acute encephalopathy due to the association of lithium carbonate and haloperidol. She was treated with lithium salts for many years and the serum level of lithium was within the therapeutic range. The encephalopathy was worsened by hyperthermia, dehydration, and reintroduction of haloperidol, 5 days after the first discontinuation of the neuroleptic. The clinical features were characterized by a persistent cerebellar syndrome, more than one year after the interruption of these medications.

Retarded and aberrant splicings caused by single exon mutation in a phosphoglycerate kinase variant.

The molecular abnormality of a phosphoglycerate kinase variant which was associated with severe tissue enzyme deficiency and episodes of muscle contractions and myoglobinuria was examined. Analysis of the patient's DNA showed the existence of a nucleotide transversion A/T - C/G in exon 7. No other nucleotide change was detected in the coding region of the variant gene. The mutation should produce a single amino acid substitution Glu - Ala at protein position 251 counting from the NH2-terminal acetyl serine residue. The protein abnormality caused by the amino acid substitution cannot explain the enzyme deficiency. Northern blot hybridization indicated that the PGK mRNA content of the patient's lymphoblastoid cells was only about 10% of that of normal. Nucleotide sequence analysis revealed the existence of two PGK mRNA components in the patient's cells. The major component corresponds to the normal PGK mRNA except for A - C change at nucleotide position 755 counting from adenine of the chain initiation codon. The minor component contains 5' region (52 bases) of intron 7 between exon 7 and exon 8. An inframe chain termination codon exists in the minor mRNA component, and the COOH-terminal half is expected to be deleted in the translation product. These results indicate that the low PGK activity in the patient's tissues is mainly due to retarded and aberrant pre-mRNA splicings caused by the change of the consensus 5' splice sequence AGgt to a nonconsensus sequence CGgt at the junction between exon 7 and intron 7 of the variant gene.

Inheritance of the S113L mutation within an inbred family with carnitine palmitoyltransferase enzyme deficiency.

Deficiency of carnitine palmitoyltransferase type II (CPT II) is a clinically heterogeneous autosomal recessive disorder of lipid metabolism. The most common mutation in the CPT II gene is the S113L mutation, which substitutes leucine for serine at amino acid position 113. We studied an inbred family with three affected cousins with CPT II deficiency and found the S113L mutation to be present in a homozygous state in all three patients. Pedigree analysis traced the S113L mutation back to one common ancestor. Although the patients in this family have an identical genotype at the CPT II locus, their clinical picture ranges from asymptomatic to lethal.

Bradycardia, an epileptic ictal manifestation.

Two patients with recurrent paroxysmal cardio-vascular symptoms are described. The first, an adult, suffered from syncopal events which did not respond to carbamazepine treatment and had a normal interictal EEG and ECG. The second, a child, presented with attacks of cyanosis, apnoea, and non-responsiveness in clusters, with normal interictal examinations. In both patients, prolonged simultaneous EEG and ECG monitoring demonstrated ictal bradycardia accompanied by paroxysmal discharges in the left temporal area.

On an autosomal dominant form of retinal-cerebellar degeneration: an autopsy study of five patients in one family.

We describe a family with an autosomal dominant form of retinal-cerebellar atrophy. There is an extreme variability in age of onset and severity of the clinical symptoms: some patients remain nearly asymptomatic throughout their entire life; others develop severe retinal and cerebellar symptoms after the age of 35 years; others suffer from a severe disorder with onset in adolescence and death during the third decade of life; in others the onset is in early childhood with prevalence of cerebellar symptoms. There is neither dementia nor epilepsy in any of the patients. Four out of five autopsies showed a severe retinal atrophy, and all five autopsies were also characterized by (1) a cerebellar atrophy affecting the spinocerebellar and olivocerebellar tracts, the cerebellar cortex and the efferent cerebellar pathways, (2) an involvement of the pyramidal pathways and of the motor neurons of brain stem and spinal cord, and (3) an atrophy of the subthalamic nucleus and to a much lesser extent of the pallidum, with also some damage to the substantia nigra. The posterior columns are much less affected except in one patient. In this family, we have excluded linkage with the two loci for spinocerebellar ataxia, i.e., SCA1 on chromosome 6p and SCA2 on chromosome 12q as well as with the locus for Machado-Joseph disease (MJD) on chromosome 14q. A genome-wide search is currently being performed to detect the disease locus responsible.

Brain glucose metabolism in postanoxic syndrome due to cardiac arrest.

Using positron emission tomography (PET), thirteen studies of regional brain glucose utilization were performed in 12 patients with postanoxic syndrome due to cardiac arrest. Investigations were carried out at least one month after brain anoxia. Seven subjects were in a persistent vegetative state. The others had regained normal consciousness with various residual neurological signs. When compared with normal values obtained in 16 normal, age-matched subjects, mean cerebral glucose metabolism was drastically decreased (+/- 50%) in vegetative cases, and to a lesser degree (+/- 25%) in conscious subjects. The most consistent regional alterations were observed in the parieto-occipital cortex (9 cases), the frontier between vertebral and carotid arterial territories. Other selective anomalies were found in the frontomesial junction (5 cases), the striatum (3 cases with dystonia), and the visual cortex (2 cases with cortical blindness). This study suggests that cerebral anoxia results in a global brain hypometabolism, which appears related to the vigilance state, as well as in regional disturbances preferentially located in arterial border zones. Although our findings remain to be confirmed in larger series, they suggest that PET provides a useful index of residual brain tissue function after anoxia and may assist in the monitoring of postanoxic encephalopathies.

Progressive cardiac failure following orthotopic liver transplantation for type IV glycogenosis.

Orthotopic liver transplantation (OLT) has been proposed to treat patients with type IV glycogenosis because of early progressive cirrhosis. Reports have shown absence of disease progression in other organs after OLT and even regression of cardiac amylopectin infiltration in one case. We describe a 15-month-old child in whom a liver transplant was performed for type IV glycogenosis. There were no clinical signs of extrahepatic disease before OLT. Nine months later, the patient developed progressive cardiac insufficiency and died from cardiac failure. Because of massive amylopectin deposits, decreased myofibrils in cardiac cells, and exclusion of other causes of cardiac failure, death was attributed to amylopectionosis. Our observation contrasts with the Pittsburgh experience and suggests that cardiac amylopectionosis may progress after OLT.

[Polysaccharide amylopectin-type storage myopathy]. / Myopathie par surcharge en polysaccharide de type amylopectine.

We report a late onset form of polysaccharide myopathy with progressive limb girdle muscles weakness, without cardiomyopathy. Muscle biopsy showed a vacuolar myopathy in type 1 fibres. The PAS positive diastase resistant deposits were made of filamentous material at electron microscopy similar to long chain glycogen. Muscle glycogen levels and glycogen metabolism enzymes were normal. Numerous abnormal mitochondrial with paracrystalline inclusions were observed around the storage material. Twelve patients with polysaccharide amylopectin-like storage myopathy have previously been reported. This disease must be distinguished from other diseases with polysaccharide accumulation such as branching enzyme deficiency and some cases of phosphofructokinase deficiency. In other disorders, no deficient enzymes in the glycogen pathway was found. Some of them show systemic storage (Lafora disease, adult polyglucosan body disease). Corpora amylacea, Bielchowsky bodies and basophilic degeneration of the myocardium represent localised depositions. A few inclusions can also be observed in hypothyroid myopathy. In polysaccharide myopathy allosteric inactivation of phosphofructokinase by a mitochondrial dysfunction is considered by analogy with cases of polysaccharide storage related to phosphofructokinase deficiency.

[Clinical and biochemical correlations in certain metabolic myopathies]. / Corrélations cliniques et biochimiques dans certaines myopathies métaboliques.

Muscular glycogenosis is a disease resulting from genetical abnormalities altering an enzyme which is involved in glycogen metabolism. In addition to disorders of glycogenosis and glycolysis, there are other pathological processes such as alpha-glycosidase deficiency and diseases associated with abnormal polysaccharide structure. A short review of the various diseases with their particular features is reported.

A European head injury evaluation chart.

In 1988, 40 experts (physicians, psychologists, social workers, lawyers, family association representatives...) coming from the E.E.C., the United States, Canada and Sweden met in Brussels to derive the guidelines for a minimal assessment of head injured people. This workshop led to a research contract between E.B.I.S. (European Brain Injury Society) and the E.E.C. Directorate for Science regarding a European evaluation document. The aims of the document are both clinical and scientific. Hence the document has to be simple, specific and feasible. The document has two parts: initial state and repeated follow-up. It ends with final comments and action plan. The first statistical data of the validation study concern mainly the link between initial severity of injury and final handicap, cognitive and behavioural troubles, familial and professional aspects of handicap.

[Muscular glycogenoses]. / Les glycogénoses musculaires.

Muscular glycogenosis is a disease resulting from genetic abnormalities altering an enzyme which is involved in glycogen metabolism. In addition to disorders of glycogenolysis and glycolysis, there are other pathological processes such as acid maltase (alpha-glucosidase) deficiency and diseases associated with abnormal glycogen structure. Glycolysis is the only metabolic pathway that can produce ATP in the absence of oxygen. It is then easy to understand that any disturbance in this energy pathway can result in dysfunction of the muscle machine and in a number of symptoms which are common to these abnormalities. An overall review of the various diseases know to exist on the glycogenolytic and glycolytic pathway will enable the reader to acquire a better knowledge of their particular features.

Bilateral tonic pupils and polyneuropathy in Sjögren's syndrome: a common pathophysiological mechanism?

One case associating tonic pupils and Sjögren's syndrome is reported. Neurophysiological examination also demonstrated a purely sensory neuropathy. This rare association raises the issue of a common process destroying the ciliary and spinal root ganglia in these patients.

Neuronal ceroid-lipofuscinosis: preferential metabolic alterations in thalamus and posterior association cortex demonstrated by PET.

Regional brain glucose utilisation was investigated with positron emission tomography (PET) and fluorodeoxyglucose (FDG) in four siblings with neuronal ceroid-lipofuscinosis. A consistent pattern was found, namely a decrease of glucose utilisation in all grey structures but more marked at the level of the thalamus and posterior association cortex. The severity of metabolic anomalies was correlated with the degree of clinical impairment and with disease duration; they were the most severe in the oldest patient, who was also the most affected clinically, intermediate in two others, and minimal in the subject with the shortest period of development of the disease. These observations suggest that PET is useful for the definition of anatomical targets of metabolic diseases and for the investigation of their pathophysiology.

Event-related potentials and cognitive functions in epileptic treated patients.

Antiepileptic drugs as well epilepsy itself are known to induce some cognitive impairment. Thirty-six epileptic patients under unchanged and reduced therapy conditions were followed from a clinical (seizures' evaluation, reaction times [RTs], memory tests) and neurophysiological (EEG, BAEPs, ERPs) point of view, weekly as inpatients (mean stay 8.9 weeks) and after 1 and 3 months as outpatients. This study showed on one hand no clear correlation between RTs and ERPs components, and on the other hand an improvement of the most complex RT after reduction of polytherapy or stabilization of seizures by the introduction of carbamazepine-CR in newly treated patients. These data suggest that in epileptic patients there exists a slowing of cognitive processes between the stimulus evaluation time and the motor response and that this step is improved when a reduced but efficient therapy is given.

Brain glucose metabolism in postanoxic syndrome. Positron emission tomographic study.

Thirteen positron emission tomographic studies of cerebral glucose utilization were carried out in 12 patients with postanoxic syndrome due to cardiac arrest. Seven subjects were in a persistent vegetative state. The 5 other subjects were normally conscious, but disclosed focal neurological signs. When compared with normal values, mean cerebral glucose metabolism was drastically decreased (+/- 50%) in vegetative subjects, and to a lesser degree (+/- 25%) in conscious patients. The most consistent regional alterations were found in the parieto-occipital cortex (9 cases), the frontier between vertebral and carotid arterial territories, followed by the frontomesial junction (5 cases), the striatum (3 cases with dystonia), thalamus (2 cases), and visual cortex (2 cases with cortical blindness). These data suggest that brain anoxia can result in global brain hypometabolism, which appears related to the vigilance state, as well as in regional alterations preferentially located in arterial border zones.