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Biomedical subjects

J H J Wokke

Publications and source records attributed to J H J Wokke.

At least 19 recordsLinked to original sources

Neurologic and hematologic response to fludarabine treatment in IgM MGUS polyneuropathy.

We studied the efficacy of fludarabine in 16 patients with immunoglobulin M monoclonal gammopathy of unknown significance polyneuropathy in a prospective uncontrolled trial. The modified Rankin scale improved in 5/16 patients, all of whom had a demyelinating polyneuropathy. The motor conduction velocity improved by more than 10% in two or more nerves for four of five of these patients. Hematologic response in bone marrow occurred in three of five of these patients, whereas two of five already had small polyclonal B cell populations. There were no serious side effects.

Aged↗

[Clinical reasoning and decision-making in practice. A patient with loss of vision and painful legs].

A 69-year-old man was admitted to the Department of Ophthalmology with bilateral loss of vision. For a few months he had also had shooting pains in both legs and instability of gait. Neurological examination showed loss of vision bilaterally and minor sensory disturbances of the legs with diminished tendon reflexes. As extensive further examination showed no specific abnormalities, the tentative diagnosis 'arteriitis temporalis' was made. Despite treatment with corticosteroids his condition deteriorated. Only after a repeat medical history had been taken did it become clear that in the past he had had homosexual contact with a number of partners. This increased the likelihood of a sexually transmitted disease in the differential diagnosis. In the meantime the results from serological tests became known: there were strongly elevated titres for syphilis in both serum and cerebral spinal fluid. Eventually the patient was diagnosed with neurosyphilis with ocular involvement and tabes dorsalis. He recovered almost completely in a few months after treatment with doxycycline.

Aged↗

Intake of polyunsaturated fatty acids and vitamin E reduces the risk of developing amyotrophic lateral sclerosis.

BACKGROUND: To assess whether the premorbid dietary intake of fatty acids, cholesterol, glutamate or antioxidants was associated with the risk of developing amyotrophic lateral sclerosis (ALS). METHODS: Patients referred to our clinic during 2001-2002, who had definite, probable or possible ALS according to El Escorial criteria, without a familial history of ALS, were asked to participate in a case-control study (132 patients and 220 healthy controls). A food-frequency questionnaire was used to assess dietary intake for the nutrients of interest. Multivariate logistic regression analysis was performed with adjustment for confounding factors (sex, age, level of education, energy intake, body mass index and smoking). RESULTS: A high intake of polyunsaturated fatty acid (PUFA) and vitamin E was significantly associated with a reduced risk of developing ALS (PUFA: odds ratio (OR) = 0.4, 95% confidence interval (CI) = 0.2 to 0.7, p = 0.001; vitamin E: OR = 0.4, 95% CI = 0.2 to 0.7, p = 0.001). PUFA and vitamin E appeared to act synergistically, because in a combined analysis the trend OR for vitamin E was further reduced from 0.67 to 0.37 (p = 0.02), and that for PUFA from 0.60 to 0.26 (p = 0.005), with a significant interaction term (p = 0.03). The intake of flavonols, lycopene, vitamin C, vitamin B2, glutamate, calcium or phytoestrogens was not associated with the risk of developing ALS. CONCLUSION: A high intake of PUFAs and vitamin E is associated with a 50-60% decreased risk of developing ALS, and these nutrients appear to act synergistically.

Adult↗

Long-term outcome in polymyositis and dermatomyositis.

BACKGROUND: Although polymyositis and dermatomyositis are regarded as treatable disorders, prognosis is not well known, as in the literature long-term outcome and prognostic factors vary widely. AIM: To analyse the prognostic outcome factors in polymyositis and adult dermatomyositis. METHODS: We determined mortality, clinical outcome (muscle strength, disability, persistent use of drugs and quality of life) and disease course and analysed prognostic outcome factors. RESULTS: Disease-related death occurred in at least 10% of the patients, mainly because of associated cancer and pulmonary complications. Re-examination of 110 patients after a median follow-up of 5 years showed that 20% remained in remission and were off drugs, whereas 80% had a polycyclic or chronic continuous course. The cumulative risk of incident connective tissue disorder in patients with myositis was significantly increased. 65% of the patients had normal strength at follow-up, 34% had no or slight disability, and 16% had normal physical sickness impact profile scores. Muscle weakness was associated with higher age (odds ratio (OR) 3.6; 95% confidence interval (CI) 1.3 to 10.3). Disability was associated with male sex (OR 3.1; 95% CI 1.2 to 7.9). 41% of the patients with a favourable clinical outcome were still using drugs. Jo-1 antibodies predicted the persistent use of drugs (OR 4.4, 95% CI 1.3 to 15.0). CONCLUSIONS: Dermatomyositis and polymyositis are serious diseases with a disease-related mortality of at least 10%. In the long term, myositis has a major effect on perceived disability and quality of life, despite the regained muscle strength.

Adolescent↗

Criteria for conduction block based on computer simulation studies of nerve conduction with human data obtained in the forearm segment of the median nerve.

The finding of conduction block (CB) on nerve conduction studies supports the diagnosis of potentially treatable immune-mediated neuropathies. CB in a number of axons may result in reduction of the compound muscle action potential (CMAP) on proximal versus distal stimulation (decrement). Decrement may also result from increased temporal dispersion (TD) as this leads to desynchronization and phase cancellation of the motor unit action potentials (MUAPs) out of which the CMAP is built up; polyphasia of MUAPs possibly yields additional decrement. To prove the occurrence of CB, decrement has to be larger than can be explained by increased TD or increased phase cancellation. This was established previously by simulations using MUAPs recorded in rats assuming maximal TD. Unfortunately, criteria based on human data and criteria for nerves with limited TD are not available. In the present study, criteria for CB were derived using simulations with thenar surface recorded MUAPs affected by collateral reinnervation that were obtained in patients with lower motor neurone disease (LMND). The effect of TD on decrement was determined for a wide range of TDs in the forearm segment of the median nerve and the segment distal to this. Our criteria for CB were based on area decrement because this was less influenced by TD and more by CB than amplitude decrement. The maximal area decrement in the forearm segment increased as TD in the forearm segment increased but decreased as TD in the distal segment increased. This suggests that, when desynchronization and phase cancellation occur in the distal segment due to TD, less phase cancellation and, therefore, less decrement can occur due to TD in the forearm. The finding that duration prolongation on proximal versus distal stimulation reflected TD within the forearm segment and that distal duration reflected TD in the distal segment allowed proposal of a more flexible set of criteria for forearm segments when TD in the forearm segment is limited or TD in the distal segment is pronounced. A separate investigation showed that the maximal TD in chronic inflammatory demyelinating polyneuropathy was within the range of our simulations, indicating that these were realistic. Our criteria were validated retrospectively in patients with multifocal motor neuropathy and patients with LMND. In the forearm segment of the median nerve, our criteria were more sensitive and equally specific for CB as compared with criteria for CB based on the study using rats. Our criteria have to be evaluated prospectively.

Action Potentials↗

Axon loss is an important determinant of weakness in multifocal motor neuropathy.

BACKGROUND: Multifocal motor neuropathy (MMN) is characterised by asymmetrical weakness and muscle atrophy, in the arms more than the legs, without sensory loss. Despite a beneficial response to treatment with intravenous immunoglobulins (IVIg), weakness is slowly progressive. Histopathological studies in MMN revealed features of demyelination and axon loss. It is unknown to what extent demyelination and axon loss contribute to weakness. Unlike demyelination, axon loss has not been studied systematically in MMN. Aims/ METHODS: To assess the independent determinants of weakness in MMN, 20 patients with MMN on IVIg treatment were investigated. Using a standardised examination in each patient, muscle strength was determined in 10 muscles. In the innervating nerve of each muscle, axon loss was assessed by concentric needle electromyography, and conduction block or demyelinative slowing by motor nerve conduction studies. Multivariate analysis was used to assess independent determinants of weakness. RESULTS: Needle electromyography abnormalities compatible with axon loss were found in 61% of all muscles. Axon loss, and not conduction block or demyelinative slowing, was the most significant independent determinant of weakness in corresponding muscles. Furthermore, axon loss and conduction block were independently associated with each other. CONCLUSION: Axon loss occurs frequently in MMN and pathogenic mechanisms leading to axonal degeneration may play an important role in the outcome of the neurological deficit in patients with MMN. Therapeutic strategies aimed at prevention and reduction of axon loss, such as early initiation of treatment or additional (neuroprotective) agents, should be considered in the treatment of patients with MMN.

Adult↗

Feasibility and cost efficiency of a diagnostic guideline for chronic polyneuropathy: a prospective implementation study.

BACKGROUND: Extensive investigations are often performed to reveal the cause of chronic polyneuropathy. It is not known whether a restrictive diagnostic guideline improves cost efficiency without loss of diagnostic reliability. METHODS: In a prospective multicentre study, a comparison was made between the workup in patients with chronic polyneuropathy before and after guideline implementation. RESULTS: Three hundred and ten patients were included: 173 before and 137 after guideline implementation. In all patients, the diagnosis would remain the same if the workup was limited to the investigations in the guideline. After guideline implementation, the time to reach a diagnosis decreased by two weeks. There was a reduction of 33% in the number and costs of routine laboratory investigations/patient, and a reduction of 27% in the total number of laboratory tests/patient, despite low guideline adherence. CONCLUSION: The implementation of a diagnostic guideline for chronic polyneuropathy can reduce diagnostic delay and the number and costs of investigations for each patient without loss of diagnostic reliability. Continuous evaluation strategies after guideline implementation may improve guideline adherence and cost efficiency.

Chronic Disease↗

Late onset axonal Charcot-Marie-Tooth phenotype caused by a novel myelin protein zero mutation.

A late onset axonal Charcot-Marie-Tooth phenotype is described, resulting from a novel mutation in the myelin protein zero (MPZ) gene. Comparative computer modelling of the three dimensional structure of the MPZ protein predicts that this mutation does not cause a significant structural change. The primary axonal disease process in these patients points to a function of MPZ in maintenance of the myelinated axons, apart from securing stability of the myelin layer.

Adult↗

Lack of association between VEGF polymorphisms and ALS in a Dutch population.

Sequence alterations in the promoter region of the vascular endothelial growth factor (VEGF) gene have been implicated in increasing the risk of developing ALS. VEGF promoter haplotypes were determined in 373 patients with sporadic ALS and 615 matched healthy controls in The Netherlands. No significant association between the previously reported at-risk haplotypes and ALS was found. Pooling our results with the previously studied population still showed a significant association with the AAG haplotype.

Adult↗

Multidisciplinary ALS care improves quality of life in patients with ALS.

OBJECTIVE: To examine the effect of multidisciplinary ALS care on the quality-of-life (QoL) in patients with ALS and their caregivers. METHODS: In a cross-sectional study, 208 patients with ALS and their caregivers were interviewed. QoL was assessed using the 36-item Short Form Health Survey (SF-36) and two visual analogue scales (VAS). Criteria for multidisciplinary ALS care were: an ALS team headed by a consultant in rehabilitation medicine and consisting of at least a physical therapist, occupational therapist, speech pathologist, dietician and a social worker; use of the Dutch ALS consensus guidelines for ALS care; and at least six incident ALS patients per year. RESULTS: Clinical characteristics and functional loss of the 133 patients receiving multidisciplinary ALS care and the 75 patients receiving general ALS care were similar. The percentage of patients with adequate aids and appliances was higher in those with multidisciplinary ALS care (93.1 vs 81.3%, p = 0.008), whereas the number of visits to professional caregivers was similar in both groups. Patients in the multidisciplinary ALS care group had a better mental QoL on the SF-36 Mental Summary Score than those in the general care group (p = 0.01). The difference in QoL was most pronounced in the domains of Social Functioning and Mental Health, and was independent of the presence of aids and appliances. No significant differences were found in the SF-36 Physical Summary Score, VAS, or in QoL of caregivers of patients with ALS. CONCLUSION: High standard of care improves mental quality-of-life in patients with ALS.

Aged↗

SMN genotypes producing less SMN protein increase susceptibility to and severity of sporadic ALS.

BACKGROUND: ALS is believed to be multifactorial in origin with modifying genes affecting its clinical expression. Childhood-onset spinal muscular atrophy (SMA) is an autosomal recessive disorder of motor neurons, caused by mutations of the survival motor neuron (SMN) gene. The SMN gene exists in two highly homologous variants: SMN1, the causative gene responsible for the production of the majority of functional SMN protein, and SMN2, responsible for the production of less protein but sufficient for modifying the SMA phenotype. OBJECTIVE: To test whether SMN genotypes are associated with susceptibility to and severity of sporadic ALS. METHODS: We performed competitive quantitative PCR analysis for both SMN1 and SMN2 genes in 242 clinically well-defined ALS patients and 175 controls. The combined determination of SMN1 and SMN2 copies also allowed for an estimation of the level of SMN for each patient (estimated SMN protein level = SMN1 copy number + 0.20 x SMN2 copy number). RESULTS: One copy of SMN1 was associated with an increased risk of developing ALS (odds ratio = 4.1, 95% CI = 1.2 to 14.2, p = 0.02) and ALS patients carried fewer SMN2 copy numbers (p < 0.001). Sixty-one percent of patients had an estimated protein SMN level < or = 2.2 vs only 36% of controls (p = 0.0000004). Multivariate Cox regression analyses showed that lower SMN2 copy numbers and lower levels of estimated SMN protein (hazard ratio = 1.3, 95% CI = 1.1 to 1.6, p = 0.03) were associated with an increased mortality rate. CONCLUSIONS: SMN genotypes producing less SMN protein increase susceptibility to and severity of ALS.

Adult↗

Ultrasonography shows extensive nerve enlargements in multifocal motor neuropathy.

Using ultrasonography we found multiple sites with nerve enlargement along the course of the brachial plexus, median, ulnar, and radial nerves in the majority of 21 patients with multifocal motor neuropathy. Sonography and electrophysiologic studies showed more abnormalities than expected on purely clinical grounds. Moreover, sonography revealed nerve enlargement without clinical or electrophysiologic abnormalities.

Adult↗

Malignant transformation in polyneuropathy associated with monoclonal gammopathy.

OBJECTIVE: To assess the frequency of hematologic malignancies at diagnosis and to determine the incidence and predictors of malignant transformation during follow-up in patients with polyneuropathy associated with monoclonal gammopathy. METHODS: Potential predictors of malignant transformation from medical history, hematologic, neurologic, and laboratory examination performed each 6 months were evaluated by univariable and multivariable Cox proportional hazard analysis. RESULTS: Of 193 patients with polyneuropathy associated with monoclonal gammopathy, 17 patients had a hematologic malignancy at diagnosis. The incidence rate of malignant transformation in 176 patients without a malignancy at diagnosis was 2.7/100 patient years. Weight loss, progression of the polyneuropathy, unexplained fever or night sweats, and M-protein level were independent predictors. CONCLUSIONS: Since hematologic malignancies occur frequently in polyneuropathy associated with monoclonal gammopathy, the authors suggest that all patients should be screened at diagnosis and subsequently during follow-up if malignant transformation is suspected.

Aged↗

Primary lateral sclerosis as a phenotypic manifestation of familial ALS.

Primary lateral sclerosis (PLS) is a diagnosis of exclusion in patients with progressive spinobulbar spasticity and could be part of the clinical spectrum of ALS. Unlike ALS, which is familial in 5 to 10% of the cases, PLS has been described as a sporadic disorder in adults. The authors report two patients with PLS from unrelated SOD1-negative familial ALS families. These observations provide further evidence that PLS can be linked pathophysiologically to ALS.

Adult↗

Criteria for demyelination based on the maximum slowing due to axonal degeneration, determined after warming in water at 37 degrees C: diagnostic yield in chronic inflammatory demyelinating polyneuropathy.

The diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP) is based on clinical and laboratory results and on features of demyelination found in nerve conduction studies. The criteria that are currently used to reveal demyelinative slowing in CIDP have several limitations. These criteria were only determined in lower arm and lower leg nerve segments, were not defined with respect to nerve temperature, and the relationship with distal compound muscle action potential (CMAP) amplitudes is unclear. The aim of our study was to determine criteria for demyelinative slowing for lower arm and leg segments as well as for upper arm and shoulder segments at a temperature of 37 degrees C, and to assess whether criteria have to be modified when the distal CMAP is decreased. Included were 73 patients with lower motor neuron disease (LMND), 45 patients with CIDP and 36 healthy controls. The arms and legs were warmed in water at 37 degrees C for at least 30 min prior to an investigation and thereafter kept warm with infrared heaters. The proposed criteria for demyelinative slowing were based on the maximum conduction slowing that may occur as a consequence of axonal degeneration and consisted of the upper boundary (99%) or the lower boundary (1%) of conduction values in LMND. In LMND, the maximum conduction slowing was different for arm and leg nerves and for segments within the arm nerves. Moreover, distal motor latency and motor conduction velocity were slower in nerves with distal CMAP amplitudes below 1 mV than in nerves with distal CMAP amplitudes above 1 mV. For these reasons, separate criteria were proposed for arm nerves, for leg nerves and for different segments within arm nerves, and more stringent criteria were proposed for distal motor latency and motor conduction velocity when the distal CMAP amplitude was below 1 mV. The diagnostic yield in CIDP was assessed using the nerve, and not the patient, as the unit of measurement. Thus, whether demyelinative slowing was present was determined for each nerve. Compared with other criteria, our criteria increased the specificity without affecting sensitivity. We conclude that the present criteria, based on the maximum slowing that may occur as a result of axonal degeneration, allow more accurate detection of demyelinative slowing in CIDP compared with other criteria. It should be emphasized that the proposed criteria can only be applied if the method of warming in water at 37 degrees C for at least 30 min is adopted.

Action Potentials↗

Physical activity and the association with sporadic ALS.

OBJECTIVE: To assess whether lifetime physical activity during work and leisure time is associated with an increased risk of developing ALS and to determine the association between physical activity and duration or age at onset of disease. METHODS: Patients referred to our clinic during the 1-year period 2001 to 2002 who had definite, probable, or possible ALS according to El Escorial criteria, without a familial history of ALS, were asked to participate in the study. A case-control study was performed taking into account all occupational and leisure time activities of patients (n = 219) and controls (n = 254). Multivariate analysis included confounding factors (sex, age, level of education, body mass index, alcohol use, and smoking). Three quantitative measures of cumulative physical activity were calculated: until 1 year before the onset of disease (total physical activity), the last 10 years before the onset of disease (late physical activity), and until the age of 25 (early physical activity). In addition, a systematic review of all published data is presented. RESULTS: Smoking and alcohol use were independently associated with ALS (current smoking increased risk, OR = 1.8, 95% CI = 1.0 to 3.0, p = 0.03, ever/current alcohol use decreased risk, OR = 0.6, 95% CI = 0.3 to 0.9, p = 0.04). No significant association with occupational or leisure time physical activity was found (all ORs < or = 1.7), which was in agreement with most studies with the highest level of evidence in the systematic review. Higher leisure time activities were associated with an earlier age at onset: activity levels before age of 25 (p < 0.001, 7 years earlier), and activity during the last 10 years (p < 0.001, 3 years earlier). CONCLUSIONS: There is no association between physical activity and the risk of developing ALS.

Adult↗

Few adverse effects of long-term creatine supplementation in a placebo-controlled trial.

Although oral creatine supplementation is very popular among athletes, no prospective placebo-controlled studies on the adverse effects of long-term supplementation have yet been conducted. We performed a double-blind, placebo-controlled trial of creatine monohydrate in patients with the neurodegenerative disease amyotrophic lateral sclerosis, because of the neuroprotective effects it was shown to have in animal experiments. The purpose of this paper is to compare the adverse effects, and to describe the effects on indirect markers of renal function of long-term creatine supplementation. 175 subjects (age = 57.7 +/- 11.1 y) were randomly assigned to receive creatine monohydrate 10 g daily or placebo during an average period of 310 days. After one month, two months and from then on every fourth month, adverse effects were scored using dichotomous questionnaires, plasma urea concentrations were measured, and urinary creatine and albumin concentrations were determined. No significant differences in the occurrence at any time of adverse effects due to creatine supplementation were found (23 % nausea in the creatine group, vs. 24 % in the placebo group, 19 % gastro-intestinal discomfort in the creatine group, vs. 18 % in the placebo group, 35 % diarrhoea in the creatine group, vs. 24 % in the placebo group). After two months of treatment, oedematous limbs were seen more often in subjects using creatine, probably due to water retention. Severe diarrhoea (n = 2) and severe nausea (n = 1) caused 3 subjects in the creatine group to stop intake of creatine, after which these adverse effects subsided. Long-term supplementation of creatine did not lead to an increase of plasma urea levels (5.69 +/- 1.47 before treatment vs. 5.26 +/- 1.44 at the end of treatment) or to a higher prevalence of micro-albuminuria (5.4 % before treatment vs. 1.8 % at the end of treatment).

Administration, Oral↗

Ulnar neuropathy at the elbow: follow-up and prognostic factors determining outcome.

OBJECTIVE: To determine the outcome in patients with ulnar neuropathy at the elbow (UNE) treated surgically or conservatively, and the prognostic value of clinical, sonographic, and electrophysiologic features. METHODS: After a median follow-up of 14 months, 69 of 84 patients initially included in a prospective blinded study on the diagnostic value of sonography in UNE were re-evaluated. The patients underwent renewed systematic clinical and sonographic examination. Patients were scored as having a poor (stable or progressive symptoms) or favorable (complete remission of symptoms or improvement) outcome. RESULTS: Of the 74 initially affected arms, 12 (16%) had a complete remission, 21 (28%) improved, 25 (34%) remained stable, and 16 (22%) had progression. Surgically treated patients (28 arms) had a more favorable outcome than those treated conservatively (p = 0.03). After surgery, the mean ulnar nerve diameter decreased from 3.2 to 2.9 mm (p = 0.03), while this was not seen after conservative treatment. Multiple logistic regression analysis showed that more outspoken nerve enlargement found during sonography at the time of the diagnosis was associated with a poor outcome (OR: 2.9, p = 0.009). Furthermore, the presence of a motor conduction block (OR: 0.2, p = 0.03) and motor velocity slowing across the elbow (OR: 0.1, p = 0.01) were associated with a favorable outcome. CONCLUSION: More pronounced ulnar nerve thickening at the time of the diagnosis is associated with poor outcome at follow-up, especially in conservatively treated cases, while electrodiagnostic signs of demyelination on testing indicate favorable outcome.

Adult↗