Ocular myasthenia gravis: diagnosis often delayed

When a patient complains of a fluctuating ptosis or diplopia the diagnosis 'ocular myasthenia gravis' must be considered. The diagnosis can be difficult because of the subtle symptoms and less sensitive diagnostic testing. Because of this, there is often a patient and doctors delay. We describe 3 patients, a 63-year-old man, a 49-year-old woman and a 77-year-old woman, who received the right diagnosis only after 22 months, 4 months and even 9 years after the first symptom occurred. At the neurological examination the provocation tests are of high importance. Confirmation of the diagnosis can be established with the following diagnostic procedures: neostigmine test, serological testing for antibodies against acetylcholine receptors and single fibre EMG.     

Assessment of Prevalence of Persons with Down Syndrome: A Theory‐based Demographic Model

Background The Netherlands are lacking reliable empirical data in relation to the development of birth and population prevalence of Down syndrome. For the UK and Ireland there are more historical empirical data available. A theory‐based model is developed for predicting Down syndrome prevalence in the Netherlands from the 1950s onwards. It is likewise applied to Ireland and the UK for the purpose of validation. Furthermore, a prediction to 2050 is constructed. Materials and Methods Maternal age births data in the general population, maternal age related risk of Down syndrome, data on selective terminations of Down syndrome pregnancies and mortality rates (from 35 studies from the 1930s until today) were obtained to create this model. Results For the Netherlands, nowadays birth prevalence is estimated at 14 per 10 000 with around 275 total annual births. The impact of selective abortion is lower than in the UK. Present Dutch Down syndrome population prevalence is estimated, according to this theory‐based model, at 7.7 per 10 000 and the grand total at 12 600 individuals. The prevalence of ‘older’ persons with Down syndrome (over 40 years of age) in the Netherlands will reach a peak in 2010, a doubling compared to 1990, implying an increased demand on medical care and counselling. Validity of this theory‐based model was examined by comparison with relevant available empirical data from the three countries. The model shows a good fit with historical empirical research, notably four UK and two Irish population prevalence studies and eight birth prevalence studies. Conclusions A theory‐based model for Down syndrome prevalence provides supplementary data in situations with a lack of empirical material and can be used for understanding and predicting long‐term developments.     

Paroxysmal kinesigenic dyskinesia: cortical or non-cortical origin

Paroxysmal kinesigenic dyskinesia (PKD) is characterized by involuntary dystonia and/or chorea triggered by a sudden movement. Cases are usually familial with an autosomal dominant inheritance. Hypotheses regarding the pathogenesis of PKD focus on the controversy whether PKD has a cortical or non-cortical origin. A combined familial trait of PKD and benign familial infantile seizures has been reported as the infantile convulsions and paroxysmal choreoathetosis (ICCA) syndrome. Here, we report a family diagnosed with ICCA syndrome with an Arg217STOP mutation. The index patient showed interictal EEG focal changes compatible with paroxysmal dystonic movements of his contralateral leg. This might support cortical involvement in PKD.     

Exaggerated startle reactions

The origin of the startle reflex lies in the caudal brainstem; it can be elicited by an unexpected stimulus resulting in a bilateral activation of many muscles. Two subsequent responses can be measured during EMG recordings; after the initial motor reflex, lasting until about 150 ms, a second response can occur. The second response contains more emotional and voluntary behavioral responses. Clinically, syndromes with hyperstartling as common feature can be divided into three groups: hyperekplexia, stimulus-induced disorders, and neuropsychiatric disorders. Classification of startle syndromes within these three groups remains challenging. Generalized stiffness at birth, excessive startling and temporary generalized stiffness after being startled point towards hyperekplexia. Stimulus-induced disorders are distinguished by careful clinical and neurophysiological evaluation, including video recordings. Neuropsychiatric disorders usually have additional behavioural and psychiatric symptoms. Polymyographic EMG startle recordings exhibit an exaggeration of the initial motor startle reflex in hyperekplexia, while neuropsychiatric startle syndromes demonstrate a variable response pattern and abnormal behavioural features. Neurophysiological investigation of the startle reflex can help to further delineate between the startle syndromes and unravel the aetiology of neuropsychiatric startle disorders.     

Benign paroxysmal positional vertigo

Benign paroxysmal positional vertigo is a common malfunction of the labyrinth, most frequently of the posterior canal, due to clot of debris in the endolymph. The attacks of vertigo are characterised by dependency on position, latency after positioning of the head, short duration, nystagmus, reversibility and fatiguableness. The diagnosis can be based on history, physical examination and provocative tilting of the head as described by Dix and Hallpike. In a typical case further investigations are not necessary. The symptoms often improve spontaneously. Half of the patients can be cured directly by stepwise tilting. This probably removes the clot from the canal of the labyrinth to the utriculus. Specific positional exercises also often have a good result, but not as quickly. Drug therapy has no place in the treatment.     

Polymorphisms in the brain-specific thyroid hormone transporter OATP1C1 are associated with fatigue and depression in hypothyroid patients

Introduction Some hypothyroid patients continue to have significant impairments in psychological well‐being, despite adequate treatment with levothyroxine (LT4). T4 transport across the blood–brain barrier is one of the crucial processes for thyroid hormone action in the brain. OATP1C1, a thyroid hormone transporter expressed at the blood–brain barrier, is considered to play a key role in delivering serum T4 to the brain. Objective To examine whether polymorphisms in OATP1C1 are determinants of well‐being, neurocognitive functioning and preference for replacement therapy with a combination of LT4 and liothyronine (LT3). Design and participants We studied 141 patients with primary autoimmune hypothyroidism, adequately treated with LT4 monotherapy and participating in a randomized clinical trial comparing LT4 therapy with LT4–LT3 combination therapy. Outcome measurements Different questionnaires on well‐being and neurocognitive tests were performed at baseline. Serum thyroid parameters, OATP1C1‐intron3C > T, OATP1C1‐Pro143Thr and OATP1C1‐C3035T polymorphisms were determined. Results Allele frequencies of the OATP1C1 polymorphisms in patients with primary hypothyroidism were similar to those of healthy controls. Both the OATP1C1‐intron3C > T and the OATP1C1‐C3035T polymorphism, but not the OATP1C1‐Pro143Thr polymorphism, were associated with symptoms of fatigue and depression. OATP1C1 polymorphisms were not associated with measures of neurocognitive functioning or preference for combined LT4–LT3 therapy. Conclusions OATP1C1 polymorphisms are associated with fatigue and depression, but do not explain differences in neurocognitive functioning or appreciation of LT4–LT3 combination therapy. Future studies are needed to confirm these findings.     

Cardiovascular disease in the Netherlands, 1975 to 1995: decline in mortality, but increasing numbers of patients with chronic conditions

OBJECTIVE: To examine the relation between trends over time in mortality and hospital morbidity caused by various cardiovascular diseases in the Netherlands. DESIGN: Trend analysis by Poisson regression of national data on mortality and hospital admissions from 1975 to 1995. SUBJECTS: The Dutch population. RESULTS: All cardiovascular diseases combined were responsible for 39% of all deaths and 16% of all hospital admissions in 1995. From 1975 to 1995, age adjusted cardiovascular mortality declined by an annual change of -2.0% (95% confidence intervals (CI) -2.1% to -1.9%), while in the same period age adjusted discharge rates increased annually by 1. 3% (95% CI 1.1% to 1.5%). Around 60% of the gain in life expectancy in this period was related to lower cardiovascular mortality. For mortality, major reductions were seen in coronary heart disease (annual change -2.9%) and in stroke (-2.1%), whereas the increase in hospital admissions was mainly caused by chronic manifestations of coronary heart disease (5.1%), heart failure (2.1%), and diseases of the arteries (1.8%). In recent years, the gap between men and women at risk of dying from coronary heart disease became smaller for those aged 相似文献