Electro-clinical features in epileptic children with chromosome 15q duplication syndrome.

OBJECTIVE: We aimed to describe epilepsy and EEG patterns related to vigilance states and age, in chromosome15-long-arm-duplication-syndrome (dup15q) children with epilepsy, in both duplication types: interstitial (intdup15) and isodicentric (idic15). METHODS: Clinical data and 70 EEGs of 12 patients (5 intdup15, 7 idic15), followed from 4.5 m.o to 17y4m (median follow-up 8y3m), were retrospectively reviewed. EEGs were analyzed visually and using power spectrum analysis. RESULTS: Seventy video-EEGs were analyzed (1-16 per patient, median 6), follow-up lasting up to 8y10m (median 4y2m): 25 EEGs in intdup15 (8 m.o to 12y.o, median 4y6m) and 45 EEGs in idic15 (7 m.o to 12 y.o, median 15 m). Epilepsy: 6 West syndrome (WS) (2intdup15, 4idic15); 4 Lennox-Gastaut syndromes (LGS) (1 intdup15, 3 idic15), 2 evolving from WS; focal epilepsy (3 intdup15). In idic15, WS displayed additional myoclonic seizures (3), atypical (4) or no hypsarrhythmia (2) and posterior predominant spike and polyspike bursts (4). Beta-band rapid-rhythms (RR): present in 11 patients, power decreased during non-REM-sleep, localization shifted from diffuse to anterior, peak frequency increased with age. CONCLUSION: WS with peculiar electro-clinical features and LGS, along with beta-band RR decreasing in non-REM-sleep and shifting from diffuse to anterior localization with age are recognizable features pointing towards dup15q diagnosis in children with autism spectrum disorder and developmental delay. SIGNIFICANCE: This study describes electroclinical features in both interstitial and isodicentric duplications of chromosome 15q, in epileptic children, including some recent extensions regarding sleep features; and illustrates how the temporo-spatial organization of beta oscillations can be of significant help in directing towards dup15q diagnosis hypothesis.

Prevalence and clinical features of opioid-induced constipation in the general population: A French study of 15,000 individuals.

BACKGROUND: Constipation is common during opioid therapy and can compromise analgesia. AIM: The aim of this article is to determine the prevalence and clinical characteristics of opioid-induced constipation (OIC) in France. METHODS: A questionnaire study was conducted in a representative sample of the French general population. Participants completed a 31-item questionnaire covering opioid use during the previous six months, and the occurrence of constipation (defined as <3 bowel movements per week, straining during defaecation, or both) during opioid treatment. RESULTS: Data were obtained from 15,213 participants, of whom 4753 (31.2%) reported opioid use. Most analgesics (96.5%) were classified as World Health Organization step II analgesics, and the remainder were step III. The most common indications for opioids were bone or joint pain, and soft tissue pain. Overall, 414/4753 (8.7%) opioid users reported OIC while the prevalence of OIC reached 21% in case of regular or prolonged (>1 month) opioid use. Other characteristics associated with OIC included female gender, age ≥50 years and use of step III opioids. Only 177/414 (42.8%) participants with OIC had used medications (most commonly osmotic laxatives) to treat constipation, and satisfaction with constipation medication was moderate (mean (SD) score 7.2 (1.3) on a scale of 0-10). CONCLUSIONS: Approximately one-third of a representative French population had used opioids within the previous six months, and 9% of users had experienced OIC, which is more frequent in case of regular use. OIC appears to be under-treated, and participants' satisfaction with their constipation medications was only moderate, suggesting that significant unmet need remains in OIC management.

Long-term EEG in children.

Long-term video-EEG corresponds to a recording ranging from 1 to 24 h or even longer. It is indicated in the following situations: diagnosis of epileptic syndromes or unclassified epilepsy, pre-surgical evaluation for drug-resistant epilepsy, follow-up of epilepsy or in cases of paroxysmal symptoms whose etiology remains uncertain. There are some specificities related to paediatric care: a dedicated pediatric unit; continuous monitoring covering at least a full 24-hour period, especially in the context of pre-surgical evaluation; the requirement of presence by the parents, technician or nurse; and stronger attachment of electrodes (cup electrodes), the number of which is adapted to the age of the child. The chosen duration of the monitoring also depends on the frequency of seizures or paroxysmal events. The polygraphy must be adapted to the type and topography of movements. It is essential to have at least an electrocardiography (ECG) channel, respiratory sensor and electromyography (EMG) on both deltoids. There is no age limit for performing long-term video-EEG even in newborns and infants; nevertheless because of scalp fragility, strict surveillance of the baby's skin condition is required. In the specific context of pre-surgical evaluation, long-term video-EEG must record all types of seizures observed in the child. This monitoring is essential in order to develop hypotheses regarding the seizure onset zone, based on electroclinical correlations, which should be adapted to the child's age and the psychomotor development.

[French guidelines on electroencephalogram]. / Recommandations françaises sur l'électroencéphalogramme.

Electroencephalography allows the functional analysis of electrical brain cortical activity and is the gold standard for analyzing electrophysiological processes involved in epilepsy but also in several other dysfunctions of the central nervous system. Morphological imaging yields complementary data, yet it cannot replace the essential functional analysis tool that is EEG. Furthermore, EEG has the great advantage of being non-invasive, easy to perform and allows control tests when follow-up is necessary, even at the patient's bedside. Faced with the advances in knowledge, techniques and indications, the Société de Neurophysiologie Clinique de Langue Française (SNCLF) and the Ligue Française Contre l'Épilepsie (LFCE) found it necessary to provide an update on EEG recommendations. This article will review the methodology applied to this work, refine the various topics detailed in the following chapters. It will go over the summary of recommendations for each of these chapters and underline proposals for writing an EEG report. Some questions could not be answered by the review of the literature; in those cases, an expert advice was given by the working and reading groups in addition to the guidelines.

Normal EEG in childhood: from neonates to adolescents.

The important EEG changes that occur throughout childhood are a major challenge for the neurophysiologist. These reflect brain maturation, which is especially fast during the first year of life. This article describes normal EEG features and variants, characteristic patterns of development, as well as some patterns that are unusual for age, from the neonatal period to adolescence. We also describe how to adapt techniques and prepare patients in order to get interpretable records of appropriate duration, in neonates, infants, and young children.

[Abnormal electroencephalography results and specific language impairment: towards a theoretical neurodevelopmental model?]. / Anomalies électroencéphalographiques paroxystiques et troubles spécifiques du langage de l'enfant : vers un modèle neurodéveloppemental ?

BACKGROUND: Specific language impairment (SLI) is a primary developmental disorder in which language is significantly more impaired than other developmental domains. Abnormal electroencephalographic recordings without clinical seizures are often observed. The aim of this retrospective study was to characterize the frequency of these abnormalities, to describe them and to analyze their association with anamnestic, clinical, paraclinical and evolution characteristics. METHODS: The cases of 35 children with a diagnosis of SLI, who also underwent electroencephalography and MRI, were systematically reviewed retrospectively. RESULTS: In this population, aged between 4 and 7 years, 49% (n=17) of patients exhibited a specific expressive language disorder and 51% (n=18) a specific receptive disorder. Forty-nine percent of the children featured abnormal electroencephalography results. Abnormalities were essentially localized on the left side of the brain and in two specific regions: the temporo-occipital (60%) and the frontorolandic (30%) regions. The groups with and without abnormalities were compared statistically with each other in terms of clinical, paraclinical and evolution characteristics. Evolution data were available for 24 patients through a telephone interview and for nine patients through a new complete language evaluation. The comparison of the two groups showed significant differences in terms of severity of the phonological disorder, a higher number of delayed acquisition of walking and cleanliness and a higher range of non specific psychomotor difficulties. DISCUSSION: A large proportion of children suffering from SLI present abnormal electroencephalography recordings with no clinical seizures. This rate is much higher than in the general population and the abnormalities are essentially localized on the left side of the brain in regions known for their specific role in language development. These abnormalities are more frequent in children with a severe phonological disorder, suggesting that they may share common pathophysiological features with SLI. CONCLUSION: The presence of EEG abnormalities in a large group of patients suffering from SLI associated with minor neurological abnormalities suggests a possible theoretical neurodevelopmental model. Minor neurodevelopmental abnormalities, genetically transmitted or acquired during the pre- or perinatal period, may create vulnerability towards SLI. This vulnerability, in conjunction with environmental influences such as family environment, linguistic stimuli, exposure to multiple languages, or transitory hearing loss, might take the form of SLI. This hypothesis underlines the importance of prevention and early detection of SLI when identifying vulnerable subjects. Monitoring the family early through parental guidance and early school support would facilitate the acquisition of language.

A prospective open-labeled trial with levetiracetam in pediatric epilepsy syndromes: continuous spikes and waves during sleep is definitely a target.

Although LVT is currently extensively prescribed in childhood epilepsy, its effect on the panel of refractory epilepsy syndromes has not been entirely evaluated prospectively. In order to study the efficacy and safety of LVT as adjunctive therapy according to syndromes, we included 102 patients with refractory seizures (6 months to 15 years) in a prospective open-labeled trial. The responder rate was respectively 36% and 32% at 3 and 6 months with 6% and 7% patients becoming seizure free. Among the responders at 6 months (n=33), seizure frequency decreased by 66% and 79% at 3 and 6 months LVT compared to baseline. The highest benefit was for CSWS patients with 2/3 responders, 50% seizure free and no aggravation. LVT provided respectively 39% and 42% responders in focal and absence epilepsies. Infantile spasms and Dravet syndrome experienced the lowest efficacy. No patient with myoclonic-astatic epilepsy or Lennox-Gastaut syndrome was aggravated. LVT dose over 40 mg/kg/d was associated with a lower response rate. Tolerability was excellent. In spite of a small sample, we assume that CSWS is a good candidate for a randomized-controlled trial with LVT.

Inactivation of animal and human prions by hydrogen peroxide gas plasma sterilization.

Prions cause various transmissible spongiform encephalopathies. They are highly resistant to the chemical and physical decontamination and sterilization procedures routinely used in healthcare facilities. The decontamination procedures recommended for the inactivation of prions are often incompatible with the materials used in medical devices. In this study, we evaluated the use of low-temperature hydrogen peroxide gas plasma sterilization systems and other instrument-processing procedures for inactivating human and animal prions. We provide new data concerning the efficacy of hydrogen peroxide against prions from in vitro or in vivo tests, focusing on the following: the efficiency of hydrogen peroxide sterilization and possible interactions with enzymatic or alkaline detergents, differences in the efficiency of this treatment against different prion strains, and the influence of contaminating lipids. We found that gaseous hydrogen peroxide decreased the infectivity of prions and/or the level of the protease-resistant form of the prion protein on different surface materials. However, the efficiency of this treatment depended strongly on the concentration of hydrogen peroxide and the delivery system used in medical devices, because these effects were more pronounced for the new generation of Sterrad technology. The Sterrad NX sterilizer is 100% efficient (0% transmission and no protease-resistant form of the prion protein signal detected on the surface of the material for the mouse-adapted bovine spongiform encephalopathy 6PB1 strain and a variant Creutzfeldt-Jakob disease strain). Thus, gaseous or vaporized hydrogen peroxide efficiently inactivates prions on the surfaces of medical devices.

Management of gastroesophageal reflux disease by primary care physicians and gastroenterologists: a prospective study of patients' records.

BACKGROUND: We previously compared the perceptions and practices of primary care physicians (PCP) and gastroenterologists (GE) in the management of gastroesophageal reflux disease (GORD), but the data were only declarative statements. OBJECTIVE: The aim of the present study was to analyze the respective management of GORD by PCP and GE on the basis of patients' records, and to look for any discrepancies between the declared and actual practices in both groups of physicians in the management of GORD. METHODS: A representative sample of French physicians was asked to enroll two consecutive patients with frequent and typical symptoms of GORD into a prospective observational survey. RESULTS: A total of 136 PCP and 91 GE participated in the survey and enrolled 271 and 182 patients, respectively, with frequent GORD symptoms (453 patients in total). Patients consulting GE were slightly younger, and had waited longer before arranging a consultation despite having symptom severity and impact on daily life similar to those visiting PCP. Most patients enrolled by GE had undergone upper GI endoscopy (95% versus 64% from PCP, P<0.01). In both groups of physicians, recourse to endoscopy for their patients was more frequent than they estimated. Prescription therapies for GORD were usually Proton Pump Inhibitors (PPI) in both groups of physicians and were in keeping with the declared findings. CONCLUSIONS: Despite differences between patients' characteristics, the management of frequent GORD was similar by both groups of physicians. The reasons why both groups of physicians underrated their actual recourse to endoscopy for their patients warrant further investigation.

Nonsteroidal anti-inflammatory drug use as a risk factor for gastro-oesophageal reflux disease: an observational study.

BACKGROUND: Although the associations between nonsteroidal anti-inflammatory drugs (NSAIDs) and peptic ulcer disease or dyspepsia are well established, fewer data exist concerning the relationship between NSAIDs and gastro-oesophageal reflux disease (GERD). AIM: To examine the relationship between NSAIDs and GERD. METHODS: A self-administered questionnaire covering NSAID use and GERD symptoms (heartburn and acid regurgitation) was sent to a representative national sample of 10,000 French adults (> or = 18 years) between 14 October and 21 November 2005. Risk factors associated with GERD were identified by logistic regression analysis in respondents who were not taking aspirin or proton pump inhibitors. FINDINGS: A total of 7259 completed questionnaires were returned of which 6823 were evaluable. Overall, 2262 respondents (33%) reported using NSAIDs during the previous 3 months. The lifetime and 3-month prevalence rates of GERD symptoms were 37% and 21% respectively. GERD symptoms were significantly more common among NSAID users than among non-users (27% vs. 19%, P < or = 0.001) and a similar trend was seen for aspirin use. Proton pump inhibitors were received by 31% of respondents who reported experiencing GERD symptoms within the previous 3 months compared with 6% of those without symptoms (P < 0.01); however, only 20% of NSAID-treated respondents were receiving proton pump inhibitors. NSAID use, age and female gender were independent predictors of GERD symptoms. CONCLUSION: NSAID or aspirin use is a significant risk factor for GERD symptoms.

[Electrophysiological investigations in childhood epilepsy surgery]. / Explorations électroencéphalographiques préchirurgicales de l'enfant.

Epilepsy surgery in children is a functional surgery: its goal is to perform the resection of the epileptic brain tissue while sparing the eloquent cortex. Prolonged scalp video-EEGs allow recording of all types of seizures and play a crucial role in localizing the epileptogenic zone. Furthermore, EEG data correlation with clinical and radiological findings provides a guide for the surgical strategy: either resection without further investigations or an invasive recording procedure. In prehemispherotomy evaluation, EEG recordings confirm that limited resections are not indicated and demonstrate that the opposite hemisphere is not involved. If invasive recordings are needed, they consist in foramen ovale electrode insertion, which provides valuable information in mesial temporal lobe epilepsy, stereoelectroencephalography for children older than two years, and subdural grids associated with depth electrodes in infants or when the eloquent areas need to be carefully investigated. Such investigations allow tailoring surgery to each child.

Perceptions and practices on the management of gastro-oesophageal reflux disease: results of a national survey comparing primary care physicians and gastroenterologists.

BACKGROUND: Literature comparing generalist and specialist care is accumulating in many disease areas, but very few studies focussed on gastrointestinal diseases and little is known about gastro-oesophageal reflux disease. AIM: To compare the management of gastro-oesophageal reflux disease (GERD) by French primary care physicians and gastroenterologists. METHODS: A postal survey was conducted in a representative sample of French physicians who were asked to complete a questionnaire that consisted of 44 questions relating to their usual medical practice for the diagnostic and therapeutic management of frequent GERD. RESULTS: 136 primary care physicians and 91 gastroenterologists participated in the survey (54%). Alarm symptoms were identified more frequently by primary care physicians than gastroenterologists, but the appraisal of their seriousness was less acute by primary care physicians than gastroenterologists. Upper endoscopy was prescribed more frequently by gastroenterologists (64% vs. 38%, P < 0.01). Physicians in both groups mainly recommended lifestyle modification. For GERD treatment, most respondents declared using a 'step-down' strategy with proton pump inhibitors, and only slight differences in drug prescription were identified between primary care physicians and gastroenterologists. Both groups of physicians also have similar perception of symptom persistence after treatment, but satisfaction with treatments was slightly higher for gastroenterologists than primary care physicians (7.6 vs. 7.1 on a scale from 0 to 10, P < 0.01). CONCLUSIONS: Overall patterns of GERD diagnosis and management are comparable between primary care physicians and gastroenterologists. Both groups perceive that GERD therapy can still be improved.

[Indications of electroencephalogram in the newborn]. / Indications de l'électroencéphalogramme en période néonatale. Recommandations du groupe de neurophysiologie clinique de l'enfant.

The electroencephalogram (EEG), an easy-to-use and non invasive cerebral investigation, is a useful tool for diagnosis and early prognosis in newborn babies. In newborn full term babies manifesting abnormal clinical signs, EEG can point focal lesions or specific aetiology. EEG background activity and sleep organization have a high prognostic value. Tracings recorded over long period can detect seizures, with or without clinical manifestations, and differentiate them from paroxysmal non epileptic movements. The EEG should therefore be recorded at the beginning of the first symptoms, and if possible before any seizure treatment. When used as a neonatal prognostic tool, EEG background activity is classified as normal, abnormal (type A and type B discontinuous and hyperactive rapid tracing) or highly abnormal (inactive, paroxysmal, low voltage plus theta tracing). In such cases, the initial recording must be made between 12 and 48 h after birth, and then between 4 and 8 days of life. Severe EEG abnormalities before 12 h of life have no reliable prognostic value but may help in the choice of early neuroprotective treatment of acute cerebral hypoxia-ischemia. During presumed hypoxic-ischemic encephalopathy, unusual EEG patterns may indicate another diagnosis. In premature newborn babies (29-32 w GA) with neurological abnormalities, EEG use is the same as in term newborns. Without any neurological abnormal sign, EEG requirements depend on GA and the mother's or child's risk factors. Before 28 w GA, when looking for positive rolandic sharp waves (PRSW), EEG records are to be acquired systematically at D2-D3, D7-D8, 31-32 and 36 w GA. It is well known that numerous and persistent PRSW are related to periventricular leukomalacia (PVL) and indicate a bad prognosis. In babies born after 32 GA with clinically severe symptoms, an EEG should be performed before D7. Background activity, organization and maturation of the tracing are valuable diagnosis and prognosis indicators. These recommendations are designed (1) to get a maximum of precise informations from a limited number of tracings and (2) to standardize practices and thus facilitate comparisons and multicenter studies.

Chess-playing epilepsy: a case report with video-EEG and back averaging.

A patient suffering from juvenile myoclonic epilepsy experienced myoclonic jerks, fairly regularly, while playing chess. The myoclonus appeared particularly when he had to plan his strategy, to choose between two solutions or while raising the arm to move a chess figure. Video-EEG-polygraphy was performed, with back averaging of the myoclonus registered during a chess match and during neuropsychological testing with Kohs cubes. The EEG spike wave complexes were localised in the fronto-central region. [Published with video sequences].

Ictal SPECT in children with epilepsy: comparison with intracranial EEG and relation to postsurgical outcome.

In order to validate the ability of ictal single photon emission computed tomography (SPECT) to localize the epileptogenic zone (EZ) in children, we compared in 20 patients aged from 10 months to 17 years (mean 6.5 years) the topography of the area of increased ictal perfusion (IPA), determined on the basis of ictal minus interictal scan values, with that of the EZ determined by intracranial EEG recordings and assessed its relationship with the postsurgical outcome. Eighteen patients had symptomatic epilepsy and 10 had extratemporal epilepsy. All patients except one had an ictal injection (mean time lag from clinical seizure onset was 18 s). Ictal and interictal SPECT images were successively co-registered, normalized, subtracted, smoothed and superimposed on MRI. All patients with ictal injection exhibited one or several IPAs. The topography of the 'highest' IPA, i.e. the maximal cerebral blood flow (CBF) change between ictal and interictal SPECT, significantly colocalized with the site of onset of the discharge, and that of the lower IPAs with that of the area of propagation (P < 0.0001). At a threshold of 30% of the maximal CBF change, the IPAs detected the onset of the discharge with a sensitivity of 0.80 and a specificity of 0.70. The highest IPA localized the EZ in 12 out of 15 patients. In the three others it missed the EZ and showed the area of propagation because of rapid seizure propagation or of infraclinical seizure onset. Among the patients with favourable surgery outcome, the highest IPA colocalized with the resected area in 70% of cases. Ictal SPECT could therefore plays an important role as a non-invasive presurgical method of investigation by optimizing the placement of intracranial electrodes, thus improving the postsurgery outcome of paediatric partial epilepsy.

A gene for pyridoxine-dependent epilepsy maps to chromosome 5q31.

Pyridoxine-dependent epilepsy (PDE) is a rare autosomal recessive disorder characterized by generalized seizures in the first hours of life and responding only to pyridoxine hydrochloride. The pathogenesis of PDE is unknown, but an alteration in the binding of pyridoxal 5-phosphate to glutamic acid decarboxylase (GAD) has been postulated in patients with PDE. Results are reported for genetic linkage analyses in four families with consanguineous parents and in one family with nonconsanguineous parents. The GAD1 (2q31) and GAD2 genes (10p23) were tested and excluded. A genomewide search was subsequently performed, using microsatellite markers at an average distance of 10 cM, and the search revealed linkage of the disease-causing gene to markers on chromosome 5q31.2-q31.3 (maximum LOD score [Z(max)] 8.43 at recombination fraction [theta] 0 and Zmax=7.58 at straight theta=0 at loci D5S2017 and D5S1972, respectively). A recombination event, between loci D5S638 and D5S463, in one family defined the distal boundary, and a second recombination event between loci D5S2011 and D5S2017 in another family defined the proximal boundary of the genetic interval encompassing the PDE gene (5.1 cM). Ongoing studies may lead to the identification of the disease-causing gene.

[Alternating hemiplegia of childhoood and oculomotor anomalies]. / Hémiplégies alternantes de l'enfant et leurs anomalies oculo-motrices.

BACKGROUND: Alternating hemiplegia of childhood is a syndrome which begins in the first year of life. It is characterized by repeated attacks of uni-or bilateral hemiplegia or hemiparesia. In most cases paroxysmal manifestations are observed: movements or dystonia++ attacks, episodic nystagmus, abnormal eye movements and disturbance of the neurovegetative system, predominantly in the first year of life. ANALYSIS: In half of the cases, neurological anomalies begin during the neonatal period with a non characteristic aspect. Typical attacks take place after one year of life, sometimes associated with partial epilepsy. In a quarter of cases, the oculomotor anomalies have been known since early life. The diagnosis is made prior to one year on the basis of associated oculomotor anomalies and other symptoms without EEG arguments for epilepsy. Paroxysmal nystagmus is always found. One eye is affect in most cases, generally with horizontal and seldom with vertical movements of large variable pendular amplitude. One eye with nystagmus and the other with mydriasis is sometimes reported. Most attacks last from 30 sec to 3 min. Paroxysmal strabismus described in half of the cases seems to be generally unilateral internuclear transitory ophthalmoplegia. Finally, ocular deviations on the hemiparetic side are described. They are generally unique or sometimes associated with head deviation. Spontaneous blinking is reduced. CONCLUSION: Alternating hemiplegia of childhood is a non-epileptic sporadic, paroxysmal manifestation of unknown pathogenesis. Prognosis is poor. The presence of oculomotor signs suggests the diagnosis.

Callosotomy for epilepsy after West syndrome.

PURPOSE: To analyze the results of callosotomy in 17 children with symptomatic generalized epilepsy after West syndrome, according to the different seizure types and surgical procedures, to define selection criteria for candidates to callosotomy. METHODS: Callosotomy was performed in two successive stages. Partial callosotomy, anterior in 13 and posterior in three, was followed by completion in 14 cases in all but four patients (complete callosotomy in one stage in one, no completion in three). All patients had clinical, video-EEG, and neuropsychological evaluation before and after each stage of callosotomy, with a mean final follow-up of 4 years. RESULTS: Seizure frequency improved in only two of 13 patients after anterior callosotomy, in none of three after posterior callosotomy, but in nine of 14 after complete callosotomy. After complete callosotomy, spasms disappeared in 80% of the cases, and drop attacks, the most severe ictal event, completely stopped or were dramatically reduced in 90% of the children. One patient no longer had episodes of status epilepticus, and another one acquired the ability to walk after complete callosotomy. From the cognitive viewpoint, nine patients with improved seizure frequency after complete callosotomy also had improved behavior and cognitive functions, but two others experienced speech deterioration after posterior callosotomy at age 11 years and completion of callosotomy at age 16 years. CONCLUSIONS: As in other severe generalized epilepsies in childhood, drop attacks provide the best indication for complete callosotomy in patients with previous West syndrome. Because drop attacks can be identifiable by falls only, the previous acquisition of walking should be considered as a key feature for any benefit to be obtained.

Pyridoxine dependent epilepsy: a suggestive electroclinical pattern.

AIMS: To determine if there is an electroencephalographic pattern suggestive of pyridoxine dependent epilepsy that could be used to improve the chances of early diagnosis. METHODS: A retrospective study was made of all the clinical records and electroencephalograms of neonates identified with pyridoxine dependent seizures between 1983 and 1994, at this hospital. Neonates whose seizures began after more than 28 days of life were excluded; in all, five patients from four families were studied. Follow up ranged from 2 to 10 years. RESULTS: A history of miscarriage and neonatal death during an epileptic seizure had occurred in the siblings of two families. One mother reported rhythmic movements of her child during the last month of pregnancy. At birth, all babies were hypotonic; four had decreased visual alertness. All babies were agitated, irritable, jittery, hyperalert, and exhibited sleeplessness and a startle reaction to touch and sound. Age of onset of seizures varied from 30 minutes to 3 days. Seizures of various types were recorded in all cases on EEG tracings, including spasms, myoclonic seizures, partial clonic, and secondary generalised seizures. Burst-suppression patterns occurred in three cases, and a combination of continuous and discontinuous patterns in two others. Bilateral high voltage delta slow wave activity was observed in four patients. Psychomotor delay was severe in three patients, moderate in one, and mild in one. CONCLUSIONS: There is an identifiable EEG pattern that is highly suggestive of pyridoxine dependent epilepsy. Pyridoxine dependent epilepsy is probably underdiagnosed.