Objective: To provide evidence‐based guidelines to general neurologists for the assessment of patients with pauci‐ or asymptomatic hyperCKemia.
Background: Recent epidemiologic studies show that up ...to 20% of ‘normal’ individuals have an elevated creatine kinase activity in the serum (sCK). The possibility of a subclinical myopathy is often raised, and patients may be unnecessarily denied treatment with statins.
Search strategy: Electronic databases including Medline, the Cochrane Library and the American Academy of Neurology were searched for existing guidelines. Articles dealing with series of patients investigated for asymptomatic/pauci‐symptomatic hyperCKemia and articles dealing with myopathies that can present with asymptomatic hyperCKemia were identified and reviewed.
Results: The only guidelines found were those approved by the Italian Association of Myology Committee, and the only relevant articles identified describe class IV studies.
Recommendations: HyperCKemia needs to be redefined as values beyond 1.5 times the upper limit of normal (which itself needs to be appropriately defined). Pauci‐ or asymptomatic hyperCKemia with no apparent medical explanation may be investigated with a muscle biopsy if one or more of the following are present; the sCK is ≥3× normal, the electromyogram is myopathic or the patient is <25 years of age. In addition, women with sCK<3 times normal may be offered DNA testing because of the possibility of carrying a dystrophin mutation.
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We present three members of an Italian family affected by tubular aggregate myopathy (TAM) and congenital miosis harboring a novel missense mutation in ORAI1. All patients had a mild, late onset TAM ...revealed by asymptomatic creatine kinase (CK) elevation and congenital miosis consistent with a Stormorken‐like Syndrome, in the absence of thrombocytopathy. Muscle biopsies showed classical histological findings but ultrastructural analysis revealed atypical tubular aggregates (TAs). The whole body muscle magnetic resonance imaging (MRI) showed a similar pattern of muscle involvement that correlated with clinical severity. The lower limbs were more severely affected than the scapular girdle, and thighs were more affected than legs. Molecular analysis revealed a novel c.290C>G (p.S97C) mutation in ORAI1 in all affected patients. Functional assays in both human embryonic kidney (HEK) cells and myotubes showed an increased rate of Ca2+ entry due to a constitutive activation of the CRAC channel, consistent with a ‘gain‐of‐function’ mutation. In conclusion, we describe an Italian family harboring a novel heterozygous c.290C>G (p.S97C) mutation in ORAI1 causing a mild‐ and late‐onset TAM and congenital miosis via constitutive activation of the CRAC channel. Our findings extend the clinical and genetic spectrum of the ORAI1‐related TAM.
Objectives
High-frequency ultrasound (HFUS 18–20 MHz) performed on patients with chronic inflammatory demyelinating polyneuropathy (CIDP) shows a focal enlargement, particularly in the proximal ...segments of upper-arm motor nerves. Ultrahigh frequency ultrasound (UHFUS 30–70 MHz), having a higher spatial resolution, enables a better characterization of nerve structures. The aim of this study was to compare the two ultrasound probes in the evaluation of motor nerve characteristics in CIDP patients.
Methods
Eleven patients with definite or probable CIDP underwent an ultrasound evaluation of median and ulnar nerves, bilaterally. Nerve and fascicle cross-sectional area (CSA), vascularization, and echogenicity were assessed.
Results
Nerve and fascicle CSA were increased in the proximal segments, especially in the median nerve, in 9/11 patients and in 10/11 patients at the HFUS and UHFUS evaluations, respectively. A statistically significant difference between CSA values obtained with the two probes was found only for fascicle values. UHFUS allowed for a more precise estimation of fascicle size and number than the HFUS. We were able to identify nerve vascularization in 4/11 patients at UHFUS only.
Conclusion
UHFUS gives more detailed information on the changes in the internal nerve structure in CIDP patients. In particular, it permits to better characterize fascicle size and morphology, and to have a precise estimation of their number. Its frequency range also allows to evaluate nerve vascularization.
Significance
Ultrasound evaluation could become an adjunctive diagnostic tool for CIDP. Further studies are needed to validate the examined parameters as biomarkers for the evaluation and follow-up of CIDP patients.
Facioscapulohumeral dystrophy is a genetic disease characterized by progressive muscle weakness leading to a complex combination of postural instability, foot drop during swing and compensatory ...strategies during gait that have been related to an increased risk of falling. The aim is to assess the effect of tibialis anterior muscle weakness on foot drop and minimum toe clearance of patients with facioscapulohumeral dystrophy during gait.
Eight patients allocated to a subgroup depending on the severity of tibialis anterior muscle weakness, assessed by manual muscle testing (i.e., severe and mild weakness), and eight matched control participants underwent gait analysis at self-selected walking speeds.
Walking speed, for all facioscapulohumeral dystrophy patients, and step length, for patients with severe weakness only, were significantly decreased compared to control participants. Minimum toe clearance was similar across all groups, but its variability was increased only for patients with severe weakness. A greater foot drop was systematically observed for patients with severe weakness during swing and only in late swing for patients with mild weakness. Individual strategies to compensate for foot drop remain unclear and may depend on other muscle impairment variability.
Although all patients were able to control the average height of their foot trajectory during swing, patients with severe tibialis anterior muscle weakness exhibited increased foot drop and minimum toe clearance variability. Manual muscle testing is a simple, cheap and effective method to assess tibialis anterior muscle weakness and seems promising to identify facioscapulohumeral dystrophy patients with an increased risk of tripping.
•Foot drop during the whole swing is greater in patients with severe muscle weakness.•No significant difference in minimum toe clearance across all patients and controls.•Toe clearance variability is increased in patients with severe muscle weakness.•Manual muscle testing seems promising to identify patients at higher tripping risk.
•Patients with non-dystrophic myotonias develop coping strategies for daily living.•The French IMPACT 2022 survey evaluated how myotonia affects patients’ life.•Stiffness, pain, falls and anxiety ...impacted negatively daily life of most patients.•Patient-reported outcomes were improved in treated participants.•These results highlight the importance of effective treatments in myotonia.
Non-dystrophic myotonias (NDM) are disabling genetic diseases that impact quality of life. To reduce the impact of NDM, patients develop coping strategies such as lifestyle adaptation and avoiding key triggers. To understand how myotonia affects patients’ lives, the IMPACT survey, an online questionnaire on patient-reported outcomes, was developed based on international IMPACT questionnaire. The French IMPACT 2022 survey was completed by 47 NDM French patients. Besides muscle stiffness (98%), patients reported muscle pain (83%), falls (70%) and anxiety (77%). These issues negatively impacted abilities to work/study (49%), daily life at home (49%) and overall mobility outside (49%). Most patients (96%) reported ongoing pharmacological treatment (mexiletine, 91%) associated with improvement in muscle stiffness (100%) and reduction in falls (94%), muscle pain (87%) and anxiety (80%). Patients were moderately satisfied (19.1%), satisfied (42.6%) and very satisfied (29.8%) with the current management; 32% rated their quality of life positively (≥ 8 on 10-point scale). In conclusion, this French survey confirms the impact of myotonia on daily life and quality of life. The improvement in patient-reported outcomes in treated participants highlights the importance of managing myotonia with effective treatments. More work should be initiated to assess the importance of NDM symptom management and patients’ adherence and compliance to treatment.
Background and purpose
The aim was to define the radiological picture of facioscapulohumeral muscular dystrophy 2 (FSHD2) in comparison with FSHD1 and to explore correlations between imaging and ...clinical/molecular data.
Methods
Upper girdle and/or lower limb muscle magnetic resonance imaging scans of 34 molecularly confirmed FSHD2 patients from nine European neuromuscular centres were analysed. T1‐weighted and short‐tau inversion recovery (STIR) sequences were used to evaluate the global pattern and to assess the extent of fatty replacement and muscle oedema.
Results
The most frequently affected muscles were obliquus and transversus abdominis, semimembranosus, soleus and gluteus minimus in the lower limbs; trapezius, serratus anterior, latissimus dorsi and pectoralis major in the upper girdle. Iliopsoas, popliteus, obturator internus and tibialis posterior in the lower limbs and subscapularis, spinati, sternocleidomastoid and levator scapulae in the upper girdle were the most spared. Asymmetry and STIR hyperintensities were consistent features. The pattern of muscle involvement was similar to that of FSHD1, and the combined involvement of trapezius, abdominal and hamstring muscles, together with complete sparing of iliopsoas and subscapularis, was detected in 91% of patients. Peculiar differences were identified in a rostro‐caudal gradient, a predominant involvement of lower limb muscles compared to the upper girdle, and in the higher percentage of STIR hyperintensities in FSHD2.
Conclusion
This multicentre study defines the pattern of muscle involvement in FSHD2, providing useful information for diagnostics and clinical trial design. Both similarities and differences between FSHD1 and FSHD2 were detected, which is also relevant to better understand the pathogenic mechanisms underlying the FSHD‐related disease spectrum.
In some 5% of patients with facioscapulohumeral muscular dystrophy (FSHD), no D4Z4 repeat contraction on chromosome 4q35 is observed. Such patients, termed patients with FSHD2, show loss of DNA ...methylation and heterochromatin markers at the D4Z4 repeat that are similar to patients with D4Z4 contractions (FSHD1). This commonality suggests that a change in D4Z4 chromatin structure unifies FSHD1 and FSHD2. The aim of our study was to critically evaluate the clinical features in patients with FSHD2 in order to establish whether these patients are phenotypically identical to FSHD1 and to establish the effects of the (epi-) genotype on the phenotype.
This cross-sectional study studied 33 patients with FSHD2 from 27 families, the largest cohort described to date. All patients were clinically assessed using a standardized clinical evaluation form. Genotype analysis was performed by pulsed field gel electrophoresis and PCR; D4Z4 methylation was studied by methylation-sensitive Southern blot analysis.
FSHD2 is identical to FSHD1 in its clinical presentation. Notable differences include a higher incidence (67%) of sporadic cases and the absence of gender differences in disease severity in FSHD2. Overall, average disease severity in FSHD2 was similar to that reported in FSHD1 and was not influenced by D4Z4 repeat size. In FSHD2, a small effect of the degree of hypomethylation on disease severity was observed.
Clinically, patients with FSHD2 are indistinguishable from patients with FSHD1. The present data suggest that FSHD1 and FSHD2 are the result of the same pathophysiologic process.
Andersen's syndrome (AS) is a rare and dominantly inherited pathology, linked to the inwardly rectifying potassium channel Kir2.1. AS patients exhibit a triad of symptoms that include periodic ...paralysis, cardiac dysrhythmia and bone malformations. Some progress has been made in understanding the contribution of the Kir2.1 channel to skeletal and cardiac muscle dysfunctions, but its role in bone morphogenesis remains unclear. We isolated myoblast precursors from muscle biopsies of healthy individuals and typical AS patients with dysmorphic features. Myoblast cultures underwent osteogenic differentiation that led to extracellular matrix mineralization. Osteoblastogenesis was monitored through the activity of alkaline phosphatase, and through the hydroxyapatite formation using Alizarin Red and Von Kossa staining techniques. Patch-clamp recordings revealed the presence of an inwardly rectifying current in healthy cells that was absent in AS osteoblasts, showing the dominant-negative effect of the Kir2.1 mutant allele in osteoblasts. We also found that while control cells actively synthesize hydroxyapatite, AS osteoblasts are unable to efficiently form any extracellular matrix. To further demonstrate the role of the Kir2.1 channels during the osteogenesis, we inhibited Kir2.1 channel activity in healthy patient cells by applying extracellular Ba(2+) or using adenoviruses carrying mutant Kir2.1 channels. In both cases, cells were no longer able to produce extracellular matrixes. Moreover, osteogenic activity of AS osteoblasts was restored by rescue experiments, via wild-type Kir2.1 channel overexpression. These observations provide a proof that normal Kir2.1 channel function is essential during osteoblastogenesis.
•Recurrent Ig shortages require a responsible use.•Disability and impairment scales should be used regularly to assess Ig efficacy.•Treatment dependence should be evaluated throughout treatment.•The ...minimum effective dose should be adjusted throughout the disease course.
Treatment strategies in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) must be adapted on a case-to-case basis. Validated and reproducible tools for monitoring treatment response are required at diagnosis, when initiating treatment and throughout follow-up. A task force of French neurologists, experts in neuromuscular disease reference centers, was assembled to provide expert advice on the management of typical CIDP with intravenous immunoglobulins (Ig), and to harmonize treatment practices in public and private hospitals. The task force also referred to the practical experience of treating CIDP with Ig at the diagnostic, induction and follow-up stages, including the assessment and management of Ig dependence, and following the recommendations of the French health agency.
•The FSHD European Trial Network (FSHD ETN) will have an open membership.•There will be four working groups (WG) on clinical and genetic diagnosis (WG 1), clinical outcome measures (WG2), biomarkers ...(WG 3), and imaging outcome measures (WG4).•Network members will be appointed to reach out to countries not yet connected and to collaborate with the other organizations mentioned above, including the FSHD Clinical Trial Research Network (CTRN).•Network members will contribute to the patient expectations survey FSHD Europe is currently performing.•The network members will promote the use of agreed FSHD Core dataset across all stakeholder groups and registries, with support of TREAT-NMD.
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