Adults with a history of possible Dravet syndrome: an illustration of the importance of analysis of the SCN1A gene.

Most patients with Dravet syndrome have de novo mutations in the neuronal voltage-gated sodium channel type 1 (SCN1A) gene. We report on two unrelated fathers with severe childhood epilepsy compatible with a possible diagnosis of Dravet syndrome, who both have a child with Dravet syndrome. Analysis of the SCN1A gene revealed a pathogenic mutation in both children. One father exhibited somatic mosaicism for the mutation detected in his son. A relatively favorable cognitive outcome in patients with Dravet syndrome patients may be explained by somatic mosaicism for the SCN1A mutation in brain tissue. A mild form of Dravet syndrome in adult patients is associated with a high recurrence risk and possibly a more severe epilepsy phenotype in their offspring.

Motor function in children with cryptogenic localization related epilepsy.

INTRODUCTION: In CLRE specific learning difficulties and motor problems may occur. The aim of this study is to examine whether CLRE or the accompanying specific learning difficulties are associated with the occurring problems in motor function. METHODS: Motor functioning in 140 children with CLRE and without epilepsy, as well as with and without specific learning difficulties is compared using Chi-square. RESULTS: In the CLRE group 35% score below the 5th percentile (poor motor function). No correlations with epilepsy variables or the occurrence of specific learning difficulties is found. DISCUSSION: A subgroup of about one-third of children with CLRE are at risk for poor motor function. Their development is best monitored using a multi-dimensional approach, including cognitive development and motor functioning.

Tyrosine hydroxylase deficiency: a treatable disorder of brain catecholamine biosynthesis.

Tyrosine hydroxylase deficiency is an autosomal recessive disorder resulting from cerebral catecholamine deficiency. Tyrosine hydroxylase deficiency has been reported in fewer than 40 patients worldwide. To recapitulate all available evidence on clinical phenotypes and rational diagnostic and therapeutic approaches for this devastating, but treatable, neurometabolic disorder, we studied 36 patients with tyrosine hydroxylase deficiency and reviewed the literature. Based on the presenting neurological features, tyrosine hydroxylase deficiency can be divided in two phenotypes: an infantile onset, progressive, hypokinetic-rigid syndrome with dystonia (type A), and a complex encephalopathy with neonatal onset (type B). Decreased cerebrospinal fluid concentrations of homovanillic acid and 3-methoxy-4-hydroxyphenylethylene glycol, with normal 5-hydroxyindoleacetic acid cerebrospinal fluid concentrations, are the biochemical hallmark of tyrosine hydroxylase deficiency. The homovanillic acid concentrations and homovanillic acid/5-hydroxyindoleacetic acid ratio in cerebrospinal fluid correlate with the severity of the phenotype. Tyrosine hydroxylase deficiency is almost exclusively caused by missense mutations in the TH gene and its promoter region, suggesting that mutations with more deleterious effects on the protein are incompatible with life. Genotype-phenotype correlations do not exist for the common c.698G>A and c.707T>C mutations. Carriership of at least one promotor mutation, however, apparently predicts type A tyrosine hydroxylase deficiency. Most patients with tyrosine hydroxylase deficiency can be successfully treated with l-dopa.

Anxiety and mood disorders in narcolepsy: a case-control study.

INTRODUCTION: Narcolepsy is a primary sleeping disorder with excessive daytime sleepiness and cataplexy as core symptoms. There is increasing interest in the psychiatric phenotype of narcolepsy. Although many authors suggest an overrepresentation of mood disorders, few systematic studies have been performed and conflicting results have been reported. Anxiety disorders in narcolepsy have only received little attention. METHODS: We performed a case-control study in 60 narcolepsy patients and 120 age- and sex-matched controls from a previous population study. The Schedules for Clinical Assessment in Neuropsychiatry were used to assess symptoms and diagnostic classifications of mood and anxiety disorders. RESULTS: Symptoms of mood disorders were reported by about one third of patients. However, the prevalence of formal mood disorder diagnoses - including major depression - was not increased. In contrast, more than half of the narcolepsy patients had anxiety or panic attacks. Thirty-five percent of the patients could be diagnosed with anxiety disorder (odds ratio=15.6), with social phobia being the most important diagnosis. There was no influence of age, sex, duration of illness or medication use on the prevalence of mood or anxiety symptoms and disorders. DISCUSSION: Anxiety disorders, especially panic attacks and social phobias, often affect patients with narcolepsy. Although symptoms of mood disorders are present in many patients, the prevalence of major depression is not increased. Anxiety and mood symptoms could be secondary complications of the chronic symptoms of narcolepsy. Recent studies have shown that narcolepsy is caused by defective hypocretin signaling. As hypocretin neurotransmission is also involved in stress regulation and addiction, this raises the possibility that mood and anxiety symptoms are primary disease phenomena in narcolepsy.

Psychotic symptoms in narcolepsy: phenomenology and a comparison with schizophrenia.

OBJECTIVE: Patients with narcolepsy often experience pervasive hypnagogic hallucinations, sometimes even leading to confusion with schizophrenia. We aimed to provide a detailed qualitative description of hypnagogic hallucinations and other "psychotic" symptoms in patients with narcolepsy and contrast these with schizophrenia patients and healthy controls. We also compared the prevalence of formal psychotic disorders between narcolepsy patients and controls. METHODS: We used SCAN 2.1 interviews to compare psychotic symptoms between 60 patients with narcolepsy, 102 with schizophrenia and 120 matched population controls. In addition, qualitative data was collected to enable a detailed description of hypnagogic hallucinations in narcolepsy. RESULTS: There were clear differences in the pattern of hallucinatory experiences in narcolepsy vs. schizophrenia patients. Narcoleptics reported multisensory "holistic" hallucinations rather than the predominantly verbal-auditory sensory mode of schizophrenia patients. Psychotic symptoms such as delusions were not more frequent in narcolepsy compared to population controls. In addition, the prevalence of formal psychotic disorders was not increased in patients with narcolepsy. Almost half of narcoleptics reported moderate interference with functioning due to hypnagogic hallucinations, mostly due to related anxiety. CONCLUSIONS: Hypnagogic hallucinations in narcolepsy can be differentiated on a phenomenological basis from hallucinations in schizophrenia which is useful in differential diagnostic dilemmas.

A cost-effectiveness decision model for antiepileptic drug treatment in newly diagnosed epilepsy patients.

OBJECTIVE: To establish cost-effectiveness of antiepileptic drug (AED) treatment strategies of newly diagnosed patients with epilepsy. METHODS: A decision analysis was carried out comparing effectiveness and treatment cost of six treatment strategies comprising carbamazepine (CBZ), lamotrigine (LTG), and valproate (VPA) as first-line and second-line drugs. Three outcome groups were defined: complete success, partial success, and failure. Data on seizure control and failure due to adverse effects were derived from the literature. Data on resource use and costs were collected for each outcome group by means of a patient survey. RESULTS: Cost data were obtained from 71 patients. Cost increased from complete success to failure outcome groups. The probability of obtaining complete success varied from 64% (VPA-CBZ strategy) to 74% (LTG-VPA strategy). The strategy LTG-VPA was more effective than the least expensive strategy CBZ-VPA, but at higher costs per additional effectively treated patient. Probabilistic sensitivity analysis confirmed these findings to be robust. Subsequent analysis showed that changing inclusion criteria used in the selection of the studies from the literature had a major effect on cost-effectiveness ratios of the various strategies. The probability that LTG first-line therapy is the most cost-effective option remains small, even defining a high cost-effectiveness threshold. Nevertheless, LTG second-line strategies can be cost-effective depending on the willingness to pay for patient improvement. CONCLUSIONS: Only a few studies satisfied our inclusion criteria for employment in our decision model. Our model supports the use of conventional AEDs as first-line options for patients with newly diagnosed epilepsy. LTG second-line therapy is likely to be the most cost-effective option in case society is willing to pay more than Euro 6000 for an additional successfully treated patient. This study also illustrates that, with the data presently available, the outcome of decision analysis for AED treatment choice depends on the inclusion criteria used to select trials. Prospective real-life studies are needed in which first- and second-line treatment strategies are compared with respect to both effectiveness and costs.

The validity of a separate classification of cryptogenic localization related epilepsy amongst childhood epilepsies.

INTRODUCTION: One-third of children with epilepsy are classified as having a cryptogenic localization related epilepsy (CLRE). In cohort studies CLRE is often grouped together with either symptomatic localization related epilepsy (SLRE) or idiopathic generalized epilepsy (IGE). Therefore, this categorization is not specific enough and will not lead to prognostic or treatment information. We objectified the classification differences between these categories. METHODS: A total of 114 children admitted to our epilepsy centre underwent a standardized clinical analysis, which yielded age at onset, duration of the epilepsy, seizure frequency, seizure type, percentage of interictal epileptiform activity on EEG (IEA), type of treatment, and full scale IQ. These variables are regarded the characteristics of the epilepsy, and used in a discriminant function analysis. RESULTS: IEA was found to be the only variable to distinguish between groups of epilepsy. SLRE could easily be distinguished significantly from IGE and CLRE, while the latter two did not differ significantly. Discriminant function analysis combined the variables into two functions, applicable to classify the children. By applying this statistical analysis method, the groups clinically classified as SLRE and IGE were mostly classified as SLRE (71.4%) and IGE (57.9%). However, CLRE appeared difficult to classify (49.2%), and most children were classified as either SLRE (19%) or IGE (31.7%). CONCLUSION: The current opinion that CLRE is 'probably symptomatic' cannot be confirmed in all cases in this study. It is most likely that the current CLRE population consists of both children with eventually SLRE, as well as yet to be described syndromes to be classified as idiopathic epilepsies. We emphasize the need for separate studies regarding children with 'probably symptomatic' (cryptogenic) localization related epilepsy, as this will maximally help children, caretakers and treating physicians to achieve the best possible outcome.

Cryptogenic localization related epilepsy in children from a tertiary outpatient clinic: is neurological and neuropsychological outcome predictable?

OBJECTIVES: Up to one-third of the children with epilepsy are diagnosed with cryptogenic localization related epilepsy (CLRE). As yet, there is a lack of studies that specify the short- and long-term prognosis for this group. In this study, we systematically established neurological outcome (represented by seizure frequency) as well as neuropsychological outcome in a cohort of 68 children with CLRE who had been referred to our tertiary outpatient clinic. Also, we analysed correlations with risk and prognostic factors. PATIENTS AND METHODS: A systematic cross-sectional open clinical and non-randomized design was used including 68 children admitted to our epilepsy centre in a child neurological programme between January 1999 and December 2004. A model was defined, distinguishing risk factors with a potential effect on epileptogenesis (history of febrile seizures, family history of epilepsy, history of early mild development delay and serious diagnostic delay) and prognostic factors, with a potential effect on the course of the epilepsy (neurological symptoms or soft signs, age at onset, duration of epilepsy, seizure type, percentage of time with epileptiform activity, localization of epileptiform activity, treatment history and treatment duration). Seizure frequency was used as the primary outcome variable, whereas three neuropsychological outcomes (IQ, psychomotor delay and educational delay) were used as secondary outcome variables. RESULTS: The children experienced a broad range of seizure types with the 'absence-like' complex partial seizure as the most commonly occurring seizure type. Almost half of the children of the study sample had a high seizure frequency. They experienced several seizures per month, week or even daily seizures. Also a substantial impact on neuropsychological outcome was observed. Mean full scale IQ was 87.7, mean academic delay was almost 1 school year and 27 children showed psychomotor delay on the Movement ABC. Only 'having more than one seizure type' showed a prognostic value for seizure frequency, and no factors were found to be correlated with the secondary outcome measures. None of the risk factors show a differential impact on seizure outcome. CONCLUSION: CLRE has a non-predictable course; clinical variability is high and prognosis in many children with CLRE is obscure. Having more than one seizure type was the only factor correlated to seizure frequency. Further longitudinal studies are needed.

Compulsive spitting as manifestation of temporal lobe epilepsy.

Spitting as a seizure manifestation is described in an autistic child with a mild expression of epilepsy. Spitting became a predominant automatism of in seizure manifestation. In contrast to most cases in the literature, the epileptic discharges were localized in the left temporal lobe, an uncommon side to cause spitting seizures. By increasing the dose of carbamazepine, spitting behaviour disappeared.

The mystery of the Doctor's son, or the riddle of West syndrome.

Although the eponym "West syndrome" is used widely for infantile spasms, the originators of the term and the time frame of its initial use are not well known. This article provides historical details about Dr. West, about his son who had infantile spasms, and about the circumstances leading to the coining of the term West syndrome.