Neurometabolic disorders are treatable causes of dystonia.

A broad range of rare inherited metabolic disorders can present with dystonia. For clinicians, it is important to recognize dystonic features, but it can be complicated by the mixed and complex clinical picture seen in many neurometabolic patients. Careful phenotyping is the first step towards the diagnosis of the underlying condition and subsequent targeted treatment, further supported by imaging, biochemical diagnostics and the availability of modern diagnostic techniques such as next generation sequencing. As several neurometabolic disorders are treatable causes of dystonia, these should have priority in the diagnostic process. In the symptomatic treatment of dystonia, several therapeutic options are available. Awareness for the occurrence and optimal treatment of dystonia and other movement disorders in neurometabolic conditions is important because these symptoms can have a substantial impact on the quality of life and daily functioning; this effect is not only exerted by the dystonia itself, but also by the frequently associated non-motor features. In this paper, the highlights and key concepts of neurometabolic forms of dystonia are discussed, with a focus on phenomenology, the diagnostic approach, the most important neurometabolic aetiologies, co-occurring non-motor features and therapeutic options.

Abnormal surface EMG during clinically normal wrist movement in cervical dystonia.

We investigated whether patients with cervical dystonia (CD) have abnormal muscle activation in non-dystonic body parts. Eight healthy controls and eight CD patients performed a flexion-extension movement of the right wrist. Movement execution was recorded by surface electromyography (EMG) from forearm muscles. Although patients had no complaints concerning wrist movement and had no apparent difficulty in executing the task, they demonstrated lower mean EMG amplitude (flexor: 0.32 mV and extensor: 0.61 mV) than controls (flexor: 0.67 mV; P = 0.021 and extensor: 1.18 mV; P = 0.068; borderline significant). Mean extensor muscle contraction was prolonged in patients (1860 ms) compared with controls (1334 ms; P = 0.026). Variation in mean EMG amplitude over movements tended to be higher in patients (flexor: 43% and extensor: 35%) than controls (flexor: 34%; P = 0.072 and extensor: 26%; P = 0.073). These results suggest that CD patients also have abnormal muscle activation in non-dystonic body parts at a subclinical level. This would support the concept that in dystonia, non-dystonic limbs are in a 'pre-dystonic state'.

Non-motor symptoms and quality of life in dopa-responsive dystonia patients.

BACKGROUND: In patients with GTP-cyclohydrolase deficient dopa-responsive dystonia (DRD) the occurrence of associated non-motor symptoms (NMS) is to be expected. Earlier studies report conflicting results with regard to the nature and severity of NMS. The aim of our study was to investigate the prevalence of psychiatric disorders, sleep problems, fatigue and health-related quality of life (HR-QoL) in a Dutch DRD cohort. METHODS: Clinical characteristics, motor symptoms, type and severity of psychiatric co-morbidity, sleep problems, fatigue and HR-QoL were assessed in DRD patients with a confirmed GCH1 mutation and matched controls. RESULTS: Twenty-eight patients were included (18 adults and 10 children), from 10 families. Dystonia symptoms were well-controlled in all patients. According to the DSM IV patients significantly more often met the criteria for a lifetime psychiatric disorder than controls (61% vs. 29%, p < 0.05). In particular the frequencies of generalized anxiety and agoraphobia were higher in patients (both 29% vs. 4%, p < 0.05). Patients scored significantly higher on daytime sleepiness than controls (ESS, 11.2 vs 5.7, p < 0.05). Adult patients had significantly lower scores on the mental component of the HR-QoL (47 vs. 54, p < 0.05) than controls mainly associated with (worse) quality of sleep. CONCLUSION: NMS were highly prevalent in our cohort of DRD patients, despite adequate treatment of motor symptoms. Our findings support the accumulating evidence of an important non-motor phenotype in DRD, with possible involvement of serotonergic mechanisms. This highlights the need to address NMS and the underlying neurobiology in patients with DRD.

Signalising psychosocial problems in cancer care :the structural use of a short psychosocial checklist during medical or nursing visits.

OBJECTIVE: In this summary of literature, we evaluated 16 studies with respect to recognition and screening for psychosocial problems of cancer patients during nursing or medical visits, and with respect to the effects of providing quality of life information during these visits. METHODS: A review of the literature was conducted. To obtain the relevant literature, a search was made of two databases: Medline and Nursing and Allied Health Literature. The literature from the last 12 years - from 1993 till 2004 - was selected. RESULTS: The results show that in a number of studies a gap is demonstrated between the presence of cancer patients' psychosocial problems and health care providers' ability to signalise these problems adequately. The outcomes of these studies further show that the use of a psychosocial checklist is helpful in screening and communicating psychosocial problems, and that supplying information about quality of life facilitates provider-patient communication about these issues. CONCLUSION: None of the studies, however, provides extensive insight into the feasibility of a psychosocial checklist in daily oncology practice. Implementation projects have to be conducted focussing on conditions that block or facilitate the use of a psychosocial checklist in daily practice. PRACTICE IMPLICATIONS: By monitoring blocking and facilitating conditions strictly and, if necessary, by adjusting them, we can create guidelines to make the use of a psychosocial checklist feasible.

Clinical Pearls - how my patients taught me: The fainting lark symptom.

BACKGROUND: Compulsive movements, complex tics and stereotypies are frequent, especially among patients with autism or psychomotor retardation. These movements can be difficult to characterize and can mimic other conditions like epileptic seizures or paroxysmal dystonia, particularly when abnormal breathing and cerebral hypoxia are induced. CASE PRESENTATION: We describe an 18-year-old patient with Asperger syndrome who presented with attacks of tonic posturing of the trunk and neck. The attacks consisted of self-induced stereotypic stretching of the neck combined with a compulsive Valsalva-like maneuver. This induced cerebral hypoperfusion and subsequently dysautonomia and some involuntary movements of the arms. CONCLUSION: This patient suffered from a complex tic with compulsive respiratory stereotypies. His symptoms contain aspects of a phenomenon described in early literature as 'the fainting lark'.

Serotonergic perturbations in dystonia disorders-a systematic review.

Dystonia is a hyperkinetic movement disorder characterized by sustained or intermittent muscle contractions. Emerging data describe high prevalences of non-motor symptoms, including psychiatric co-morbidity, as part of the phenotype of dystonia. Basal ganglia serotonin and serotonin-dopamine interactions gain attention, as imbalances are known to be involved in extrapyramidal movement and psychiatric disorders. We systematically reviewed the literature for human and animal studies relating to serotonin and its role in dystonia. An association between dystonia and the serotonergic system was reported with decreased levels of 5-hydroxyindolacetic acid, the main metabolite of serotonin. A relation between dystonia and drugs affecting the serotonergic system was described in 89 cases in 49 papers. Psychiatric co-morbidity was frequently described, but likely underestimated as it was not systematically examined. Currently, there are no good (pharmaco)therapeutic options for most forms of dystonia or associated non-motor symptoms. Further research using selective serotonergic drugs in appropriate models of dystonia is required to establish the role of the serotonergic system in dystonia and to guide us to new therapeutic strategies.

Psychiatric co-morbidity is highly prevalent in idiopathic cervical dystonia and significantly influences health-related quality of life: Results of a controlled study.

INTRODUCTION: The aim of this study was to systematically investigate the prevalence of psychiatric disorders and factors influencing health-related quality of life (HR-QoL) in cervical dystonia (CD) patients, in the context of objective dystonia motor severity. METHODS: We studied 50 CD patients and 50 matched healthy controls. Psychiatric assessment included the MINI-PLUS interview and quantitative questionnaires. Dystonia motor severity (based on video evaluation), pain and disability were determined with the TWSTRS rating scale. In addition, severity of tremor and jerks was evaluated with the 7-point CGI-S scale. HR-QoL was determined with the RAND-36 item Health Survey and predictors of HR-QoL were assessed using multiple regression analysis. RESULTS: In CD patients, the MINI-PLUS revealed a significantly higher prevalence of psychiatric disorders (64% vs. 28%, p = 0.001), with substantially more depression (32% vs. 14%) and anxiety disorders (42% vs. 8%). This was confirmed by the quantitative rating scales. Disease characteristics did not differ between patients with and without a psychiatric diagnosis. HR-QoL in dystonia patients was significantly lowered. The most important predictors of HR-QoL appeared severity of depressive symptoms, pain and disability, but not severity of motor symptoms. CONCLUSION: Psychiatric co-morbidity is highly prevalent and is an important predictor of HR-QoL in CD patients, rather than dystonia motor severity. Our findings support the theory of a shared neurobiology for motor and non-motor features and highlight the need for systematic research into psychiatric disorders in dystonia. Adequate treatment of psychiatric symptoms could significantly contribute to better overall quality of life of CD patients.

Ataxia, dystonia and myoclonus in adult patients with Niemann-Pick type C.

BACKGROUND: Niemann-Pick type C (NP-C) is a rare autosomal recessive progressive neurodegenerative disorder caused by mutations in the NP-C 1 or 2 gene. Besides visceral symptoms, presentation in adolescent and adult onset variants is often with neurological symptoms. The most frequently reported presenting symptoms of NP-C in adulthood are psychiatric symptoms (38 %), cognitive decline (23 %) and ataxia (20 %). Myoclonus can be present, but its value in early diagnosis and the evolving clinical phenotype in NP-C is unclear. In this paper we present eight Dutch cases of NP-C of whom five with myoclonus. METHODS: Eight patients with genetically confirmed NP-C were recruited from two Dutch University Medical Centers. A structured interview and neuropsychological tests (for working and verbal memory, attention and emotion recognition) were performed. Movement disorders were assessed using a standardized video protocol. Quality of life was evaluated by questionnaires (Rand-36, SIP-68, HAQ). In four of the five patients with myoclonic jerks simultaneous EEG with EMG was performed. RESULTS: A movement disorder was the initial neurological symptom in six patients: three with myoclonus and three with ataxia. Two others presented with psychosis. Four experienced cognitive deficits early in the course of the disease. Patients showed cognitive deficits in all investigated domains. Five patients showed myoclonic jerks, including negative myoclonus. In all registered patients EEG-EMG coherence analysis and/or back-averaging proved a cortical origin of myoclonus. Patients with more severe movement disorders experienced significantly more physical disabilities. CONCLUSIONS: Presenting neurological symptoms of NP-C include movement disorders, psychosis and cognitive deficits. At current neurological examination movement disorders were seen in all patients. The incidence of myoclonus in our cohort was considerably higher (63 %) than in previous publications and it was the presenting symptom in 38 %. A cortical origin of myoclonus was demonstrated. Our data suggest that myoclonus may be overlooked in patients with NP-C. All patients scored significantly lower on physical domains of HRQoL. Symptomatic treatment of movement disorders may improve physical functioning and subsequently HRQoL.

Transsexual subtypes: clinical and theoretical significance.

The present study was designed to investigate whether transsexuals can be validly subdivided into subtypes on the basis of sexual orientation, and whether differences between subtypes of transsexuals are similar for male-to-female (MF) and female-to-male transsexuals (FMs). Within a large transsexual sample (n=187), homosexual and nonhomosexual subjects were compared on a number of characteristics before the start of treatment. Differences within MF and FM groups were also investigated. Homosexual transsexuals were found to be younger when applying for sex reassignment, reported a stronger cross-gender identity in childhood, had a more convincing cross-gender appearance, and functioned psychologically better than nonhomosexual transsexuals. Moreover, a lower percentage of the homosexual transsexuals reported being (or having been) married and sexually aroused while cross-dressing. The pattern of findings was different for MFs and FMs. No differences between homosexuals and nonhomosexuals were found in height, weight, or body mass index. A distinction between subtypes of transsexuals on the basis of sexual orientation seems theoretically and clinically meaningful. The results support the notion that in the two groups different factors influence the decision to apply for sex reassignment. The more vulnerable nonhomosexual transsexuals may particularly benefit from additional professional guidance before and/or during treatment.

Non-motor symptoms in genetically defined dystonia: Homogenous groups require systematic assessment.

INTRODUCTION: Dystonia is a movement disorder involving sustained or intermittent muscle contractions resulting in abnormal movements and postures. Identification of disease causing genes has allowed examination of genetically homogenous groups. Unlike the motor symptoms, non-motor characteristics are less clearly defined, despite their impact on a patient's quality of life. This review aims to examine the evidence for non-motor symptoms, addressing cohort size and methods of assessment in each study. METHODS: A systematic and standardised search strategy was used to identify the published literature relating to psychiatric symptoms, cognition, sleep disorders, sensory abnormalities and pain in each of the genetically determined dystonias. Studies were divided according to cohort size, method of assessment and whether comparison was made to an appropriate control group. RESULTS: Ninety-five articles were identified including reported clinical histories (n = 42), case reports and smaller case series (n = 12), larger case series (n = 23) and case-control cohorts (n = 18). Psychiatric symptoms were the most frequently investigated with anxiety, depression and Obsessive-Compulsive disorder being most common. Cognitive impairment involved either global deficits or isolated difficulties in specific domains. Disturbances to sleep were most common in the dopa-responsive dystonias. Sensory testing in DYT1 cases identified an intermediate subclinical phenotype. CONCLUSION: Non-motor symptoms form an integral component of the dystonia phenotype. However, future studies should involve a complete assessment of all symptom subtypes in order to understand the frequency and gene-specificity of these symptoms. This will enable early symptom identification, appropriate clinical management, and provide additional outcome measures in future clinical trials.

Patient isolation in multichannel bioelectric recordings by digital transmission through a single optical fiber.

A design for patient isolation in 64-channel ECG recordings is presented. Small dimensions of the isolated section and the use of an optical fiber as the only connection between the isolated section and the grounded section of the measurement system ensured a minimal capacitance between the patient and the environment. The consistent low-power design of the isolated section resulted in a power consumption of 210 mW, which enabled a 10 h continuous operating time of the battery powered isolated section. The system handles 64 signals with a dynamic range of 75 dB. Analog to digital conversion is performed in the isolated section with a sample rate of 1 kHz per channel. The receiver interfaces to a commercially available DMA board for a standard personal computer.

[Preferential posture in infants; serious demands on health care]. / Voorkeurshouding bij zuigelingen; groot beroep op de gezondheidszorg.

OBJECTIVE: To determine the prevalence of preferential posture in infants up to the age of six months; to determine the percentage of referrals for diagnostics and (or) treatment; to gather information about risk factors. SETTING: Infant Health Care (IHC) centres in the Netherlands. DESIGN: Descriptive controlled investigation. METHOD: During September 1995 a total of 7609 infants were examined by 167 IHC doctors for the presence of preferential posture. Data on the physical examination and on the occurrence of risk factors were registered for every child with preferential posture (n = 623) and for a next child of the same age and the same sex without preferential posture. Six months later 468 children with preferential posture were re-examined. RESULTS: The prevalence of preferential posture was 8.2% and was highest in children below 16 weeks of age. The ratio boy:girl was 3:2. Firstborns, premature children and children in breech position at the time of delivery, had a higher risk for preferential posture. The position of the child after the first week of life and the way of feeding proved to be significant risk factors. After six months 32% of the children with preferential posture had been referred for additional diagnostics and, if necessary, treatment. CONCLUSION: Preferential posture is frequently observed and leads to referral, additional diagnostics and (or) treatment in 2.5% of all children up to 6 months of age.

[No asymmetry of head rotation and shape found in three quarters of 2-3 year olds exhibiting postural preference in infancy]. / Geen asymmetrie van de hoofdrotatie en -vorm bij driekwart van de 2-3-jarigen die als zuigeling een voorkeurshouding hadden.

OBJECTIVE: Assessment of the course of signs of asymmetry in toddlers who had a preferential posture as infants. DESIGN: Descriptive. METHOD: Children who at the age of 1-6 months showed a preferential posture (n = 623) and at the age of 7-14 months displayed asymmetry of the shape and/or the rotation of the head (n = 259 of 468 children examined; 55%), were invited in 1997/'98 at the age of 2-3 years by 71 physicians of Infant Health Care Centres in the Netherlands. These physicians examined 129 children for asymmetry of the rotation and shape of the head. The parents of children with asymmetry were questioned about their reaction to the condition. RESULTS: Of the 129 children examined, 53% still had signs of asymmetry: active rotation was restricted in 6%, passive rotation in 2%, 45% had an asymmetric flattening of the occiput and 21% of the forehead. Of the 68 parents, 4 (6%) regarded the asymmetry of their child's head as a problem. CONCLUSION: Asymmetry in infants runs a favourable course with respect to rotation and shape of the head; the condition had disappeared in three-quarters of the toddlers who had shown a preferential posture as infants. Flattening of the occiput is the most persistent sign. Parents infrequently experience the asymmetry at the age of 2 to 3 years as a problem.

[Recommendations of vitamin D supplements for toddlers frequently disregarded]. / Aanbevolen vitamine-D-suppletie bij peuters veelal niet toegepast.

OBJECTIVE: To inventory the use of colecalciferol in children aged 1-4 years. DESIGN: Cross-sectional. METHOD: Fifteen health centre physicians throughout the Netherlands in April 1998 collected data on the use of colecalciferol among children aged 1 to 4 years. At the periodical medical examination, parents were asked if their child was given colecalciferol and if so, the name of the preparation and the dosage. The child's age and the mother's country of origin were also recorded. RESULTS: 660 Children were evaluated: 190 aged 1 year, 200 aged 2 years, 220 aged 3 years and 50 aged 4 years. There existed a 'top five' of preparations used by 72% of the parents. Fifty-seven per cent of the children (almost) daily received the dose of colecalciferol recommended by the Dutch Health Council (10-15 micrograms). Fifteen per cent received no suppletion at all. The percentage of nonusers increased with age from 9% of those aged 1 year to 26% of those aged 4 years. Of the children given some form of suppletion (almost) every day, 81% received the recommended dose, 16% too little and 3% too much. Suppletion according to the recommendations was found more often for children of European mothers than for children of non-European mothers. Enquiries among all university hospitals left the impression that rickets is infrequent among otherwise healthy children.

Reproducibility over a 1-month period of 1H-MR spectroscopic imaging NAA/Cr ratios in clinically stable multiple sclerosis patients.

N-acetylaspartate/creatine (NAA/Cr) ratios, assessed with proton magnetic resonance spectroscopy, are increasingly used as a surrogate marker for axonal dysfunction and degeneration in multiple sclerosis (MS). The purpose of this study was to test short-time reproducibility of NAA/Cr ratios in patients with clinically stable MS. In 35 MS patients we analysed NAA/Cr ratios obtained with (1)H-MR spectroscopic imaging at the centrum semiovale either with lateral ventricles partially included (group 1; n=15) or more cranially with no ventricles included (group 2; n=20). To test short-term reproducibility of the NAA/Cr measurements, patients were scanned twice 4 weeks apart. We determined mean NAA/Cr and Cho/Cr ratios of 12 grey matter and 24 white matter voxels. Mean NAA/Cr ratios of both the white and grey matter did not change after 4 weeks. Overall 4-week reproducibility of the NAA/Cr ratio, expressed as coefficient of variation, was 4.8% for grey matter and 3.5% for white matter. Reproducibility of cranial scanning of the ventricles was slightly better than with cerebrospinal fluid included. Our study shows good short-term reproducibility of NAA/Cr ratio measurements in the centrum semiovale, which supports the reliability of this technique for longitudinal studies.

Substrate-accelerated death of Saccharomyces cerevisiae CBS 8066 under maltose stress.

When Saccharomyces cerevisiae CBS 8066 was grown under maltose limitation, two enzymes specific for maltose utilization were present: a maltose carrier, and the maltose-hydrolysing alpha-glucosidase. The role of these two enzymes in the physiology of S. cerevisiae was investigated in a comparative study in which Candida utilis CBS 621 was used as a reference organism. Maltose pulses to a maltose-limited chemostat culture of S. cerevisiae resulted in 'substrate-accelerated death'. This was evident from: (1) enhanced protein release from cells; (2) excretion of glucose into the medium; (3) decreased viability. These effects wee specific with respect to both substrate and organism: pulses of glucose to maltose-limited cultures of S. cerevisiae did not result in cell death, neither did maltose pulses to maltose-limited cultures of C. utilis. The maltose-accelerated death of s. cerevisiae is most likely explained in terms of an uncontrolled uptake of maltose into the cell, resulting in an osmotic burst. Our results also provide evidence that the aerobic alcoholic fermentation that occurs after pulsing sugars to sugar-limited cultures of s. cerevisiae (short-term Crabtree effect) cannot solely be explained in terms of the mechanism of sugar transport. Both glucose and maltose pulses to maltose-limited cultures triggered aerobic alcohol formation. However, glucose transport by S. cerevisiae occurs via facilitated diffusion, whereas maltose entry into this yeast is mediated by a maltose/proton symport system.

Competition for glucose between the yeasts Saccharomyces cerevisiae and Candida utilis.

The competition between the yeasts Saccharomyces cerevisiae CBS 8066 and Candida utilis CBS 621 for glucose was studied in sugar-limited chemostat cultures. Under aerobic conditions, C. utilis always successfully completed against S. cerevisiae. Only under anaerobic conditions did S. cerevisiae become the dominant species. The rationale behind these observations probably is that under aerobic glucose-limited conditions, high-affinity glucose/proton symporters are present in C. utilis, whereas in S. cerevisiae, glucose transport occurs via facilitated diffusion with low-affinity carriers. Our results explain the frequent occurrence of infections by Crabtree-negative yeasts during bakers' yeast production.