Another Perspective on Fasciculations: When is it not Caused by the Classic form of Amyotrophic Lateral Sclerosis or Progressive Spinal Atrophy?

Cramp-Fasciculation Syndrome Associated with Natural and Added Chemicals in Popular Food Items

Cramp-fasciculation syndrome (CFS) is a rare and benign neuromuscular disorder that may initially masquerade as motor neuron disease/amyotrophic lateral sclerosis. While CFS may have a familial disposition, we report on cases associated with high consumption of popular food items. One set of patients reversibly experienced acute onset of headache, flushing, muscle stiffness and fasciculations following the consumption of umami-flavored food containing a large concentration of monosodium glutamate. A second group of patients consuming food derived from lupin seed developed acute cholinergic toxicity, CFS, and, with chronic intake, significant, self-limiting, but incompletely reversible upper and lower motor neuron deficits. While these cases may improve our knowledge about the possible causes of CFS, our series also demonstrates that excessive consumption of some popular foods is not harmless. This warrants further research on their safety at all stages of human development from a neurological point of view.

Benign fasciculation syndrome and migraine aura without headache as possible adverse events after BNT162b2 mRNA vaccination: a web-based survey

AIM

To determine the characteristics of patients who experienced muscle fasciculations and migraine auras without headache after BNT162b2 immunization.

METHODS

In January 2022, we published a case report that described a 48-year-old female patient who experienced muscle twitching and migraine auras without headache following BNT162b2 immunization. A self-administered online survey was sent to people who had written to us and complained of similar symptoms described in the case report (N=20).

RESULTS

The survey was completed by 11 participants, of whom 10 reported muscle twitching following BNT162b2 immunization lasting a median of 14 (4-36.5) days. Five of these participants (50%) reported migraine auras without headache. Participants further reported on self-identified triggers that altered the intensity of their symptoms, such as anxiety or caffeine. Fifty percent of participants who got an acute SARS-CoV-2 infection (3/6) experienced increased muscle symptom intensity during the acute phase of the disease.

CONCLUSION

To the best of our knowledge, our survey is the first to summarize patients' experiences of these phenomena occurring after BNT162b2 immunization. It is important to note that no causal relationship between vaccination and these phenomena can be inferred.

A Case Report on a Young Male Taking Methylphenidate With Fasciculations and Dysphagia: Correlation or Causation?

Concurrent fasciculations and oropharyngeal dysphagia (OD) can be presenting signs of motor neuron disease (MND); however, there are other causes for OD (neoplasms, surgery, and gastroesophageal diseases, among others). Fasciculations (anxiety, benign, or iatrogenic) are an uncommon side effect (<1%) of methylphenidate. A 30-year-old male noticed fasciculations in both gastrocnemii, reporting gradual cranial progression, culminating in diffuse fasciculations with facial involvement. One month later, he reported OD for solids and occasional cough for liquids. He denied weakness, fatigue, or weight loss. He has no relevant personal history, apart from attention deficit hyperactivity disorder diagnosed a year before and since then medicated with methylphenidate 40 mg id. He had no abnormal findings on neurological examination. Electromyography (EMG) and sinus CT were normal. Upper gastrointestinal (GI) endoscopy (EGD) showed reflux esophagitis grade C, which could explain OD, and he started esomeprazole 40 mg id. As there were no findings on EMG, an iatrogenic etiology for fasciculations was considered. He suspended methylphenidate for a month and, two months later, reported a substantial improvement in fasciculations and resolution of the OD with the introduction of esomeprazole. Two simultaneous symptoms do not mean they are related. In this specific case, OD was the first symptom of gastroesophageal reflux disease (GERD), and fasciculations happened as a side effect of methylphenidate. This must be taken into consideration, as it can represent a confounding factor making the differential diagnosis more difficult. To the best of our knowledge, there are no published articles similar to this case report.

Biological networks and complexity in early-onset motor neuron diseases

Motor neuron diseases (MNDs) are neuromuscular disorders where the spinal motor neurons-either the cell bodies themselves or their axons-are the primary cells affected. To date, there are 120 different genes that are lost or mutated in pediatric-onset MNDs. Most of these childhood-onset disorders, aside from spinal muscular atrophy (SMA), lack viable therapeutic options. Previous research on MNDs has focused on understanding the pathobiology of a single, specific gene mutation and targeting therapies to that pathobiology. This reductionist approach has yielded therapeutic options for a specific disorder, in this case SMA. Unfortunately, therapies specific for SMA have not been effective against other pediatric-onset MNDs. Pursuing the same approach for the other defined MNDs would require development of at least 120 independent treatments raising feasibility issues. We propose an alternative to this this type of reductionist approach by conceptualizing MNDs in a complex adaptive systems framework that will allow identification of common molecular and cellular pathways which form biological networks that are adversely affected in early-onset MNDs and thus MNDs with similar phenotypes despite diverse genotypes. This systems biology approach highlights the complexity and self-organization of the motor system as well as the ways in which it can be affected by these genetic disorders. Using this integrated approach to understand early-onset MNDs, we would be better poised to expand the therapeutic repertoire for multiple MNDs.

Benign Fasciculation Syndrome and Migraine Aura without Headache: Possible Rare Side Effects of the BNT162b2 mRNA Vaccine? A Case Report and a Potential Hypothesis

The BNT162b2 (Pfizer BioNTech) mRNA vaccine is an effective vaccine against COVID-19 infection. Here, we report an adverse event following immunization (AEFI) in a 48-year-old female patient who presented with fasciculations, migraine auras without headaches and in an increased discomfort of previously present palpitations, as well as excitation and insomnia. Her fasciculations were intermittently present until the time this paper was written, starting from the 6th day post-vaccination; they changed localization and frequency, but most commonly they were generalized, affecting almost all muscle groups. The patient also suffered from two incidents of migraine auras with visual kaleidoscope-like phenomena without headaches a few months after the vaccination. These symptoms were considered to be AEFI and no causal relation with the vaccine could be proven.

Increased muscle echointensity correlates with clinical disability and muscle strength in chronic inflammatory demyelinating polyneuropathy

BACKGROUND AND PURPOSE

We evaluated muscle echointensity as a marker for secondary axonal damage in patients with chronic inflammatory demyelinating polyneuropathy (CIDP) using ultrasonography. Findings were correlated with clinical disability and muscular strength.

METHODS

Eighty patients with CIDP (40 with typical and 40 with atypical CIDP) were examined clinically, including assessment of Medical Research Council (MRC) sum score and Inflammatory Neuropathy Cause and Treatment Overall Disability Sum Score (INCAT-ODSS). Echointensity in eight proximal and distal muscles of the arms and legs was evaluated by muscle ultrasonography using the Heckmatt scale.

RESULTS

Alterations of echointensity occurred most frequently in the distal leg muscles, with a median (range) Heckmatt score of 1.5 (1-4). There were no differences between typical and atypical CIDP patients with regard to Heckmatt score. Alterations of echointensity correlated to disability and muscle strength. The arm score of the INCAT-ODSS correlated to Heckmatt score for the distal arm muscles (r = 0.23, p = 0.046) and the leg score of the INCAT-ODSS correlated to Heckmatt scores for the proximal (r = 0.34, p = 0.002) and distal leg muscles (r = 0.33, p = 0.004). MRC sum score, as well as individual MRC scores for arm and leg muscles, correlated to Heckmatt scores of the corresponding muscle groups (r = -0.25, p = 0.02 for MRC sum score).

CONCLUSION

Increased muscle echointensity, reflecting fibrosis and fatty infiltration due to secondary axonal damage, correlated to muscular strength and disability in a large cohort of CIDP patients. Alterations of echointensity occur in both typical and atypical CIDP patients and are pronounced in the distal leg muscles.

Fasciculations demonstrate daytime consistency in amyotrophic lateral sclerosis

INTRODUCTION

Fasciculations represent early neuronal hyperexcitability in amyotrophic lateral sclerosis (ALS). To aid calibration as a disease biomarker, we set out to characterize the daytime variability of fasciculation firing.

METHODS

Fasciculation awareness scores were compiled from 19 ALS patients. In addition, 10 ALS patients prospectively underwent high-density surface electromyographic (HDSEMG) recordings from biceps and gastrocnemius at three time-points during a single day.

RESULTS

Daytime fasciculation awareness scores were low (mean: 0.28 muscle groups), demonstrating significant variability (coefficient of variation: 303%). Biceps HDSEMG recordings were highly consistent for fasciculation potential frequency (intraclass correlation coefficient [ICC] = 95%, n = 19) and the interquartile range of fasciculation potential amplitude (ICC = 95%, n = 19). These parameters exhibited robustness to observed fluctuations in data quality parameters. Gastrocnemius demonstrated more modest levels of consistency overall (44% to 62%, n = 20).

DISCUSSION

There was remarkable daytime consistency of fasciculation firing in the biceps of ALS patients, despite sparse and intermittent awareness among patients' accounts.

Cerebellar degeneration in adult spinal muscular atrophy patients

BACKGROUND

Spinal muscular atrophy (SMA) is a genetic motor neuron disease related to deletions in the SMN1 gene. There is mounting evidence that the disease is not restricted to motor neurons. In this neuroimaging study, we aimed to investigate the presence of in-vivo cerebellar damage in adult SMA patients not treated with disease-modifying treatment.

METHODS

Twenty-five molecularly confirmed patients with SMA type III or IV and 25 healthy controls underwent MRI with cerebellar focused structural analysis by the CERES automated pipeline. Volumetry (total and gray matter-GM) as well as cortical thickness of the cerebellar lobules were compared in both groups. Full clinical and demographic data were then assessed for correlations with cerebellar imaging findings.

RESULTS

Volumes of cerebellar lobules VIIIB (right), IX and X were significantly smaller in patients with SMA. Lobule IX also had GM atrophy in comparison to controls. We found no significant correlation between clinical findings and cerebellar damage.

CONCLUSIONS

Neuroimaging detects cerebellar structural changes in adult SMA patients, suggesting that neurodegeneration is not confined to the lower motor neurons in the disease.

Simple surface EMG recording as a noninvasive screening method for the detection of acute oxaliplatin-induced neurotoxicity: a feasibility pilot study

OBJECTIVES

Oxaliplatin-induced neurotoxicity can be a dose-limiting side effect to effective chemotherapy. Acute hyperexcitability causes cold-evoked sensory and motor symptoms, which resemble neuromyotonia. An accessible and non-invasive technique for early detection could help select patients for potential treatments. We assessed the use of a simple surface electromyography (sEMG) in patients directly after oxaliplatin infusion.

METHODS

In patients with colorectal cancer, acute neurotoxicity was evaluated by means of a physical examination, a questionnaire, and sEMG directly after the second and fourth cycle of oxaliplatin. Questionnaires were also assessed 1 day after infusion.

RESULTS

14 patients were measured after the second cycle and 8 patients were also measured after the fourth cycle of oxaliplatin. All patients reported to a variable degree oxaliplatin induced neurotoxicity symptoms: sensitivity to touching cold or swallowing cold items were reported as most severe. Clinical signs of hyperexcitability were observed in 55% of the measurements. Spontaneous activity compatible with neuromyotonia was observed in 82% of the sEMG recordings.

CONCLUSIONS

Patient reported symptoms, physical examination and simple sEMG are complementary measurements to detect acute oxaliplatin induced neurotoxicity. After further validation, sEMG recording can be used as a simple objective screenings tool to detect nerve hyperexcitability directly after oxaliplatin administration.

Spontaneous mechanical and electrical activities of human calf musculature at rest assessed by repetitive single-shot diffusion-weighted MRI and simultaneous surface electromyography

PURPOSE

Assessment of temporal and spatial relations between spontaneous mechanical activities in musculature (SMAM) at rest as revealed by diffusion-weighted imaging (DWI) and electrical muscular activities in surface EMG (sEMG). Potential influences of static and radiofrequency magnetic fields on muscular activity on sEMG measurements at rest were examined systematically.

METHODS

Series of diffusion-weighted stimulated echo planar imaging were recorded with concurrent sEMG measurements. Electrical activities in sEMG were analyzed by non-parametric Friedman and two-sample Kolmogorov-Smirnov test. Direct correlation of both modalities was investigated by temporal mapping of electrical activity in sEMG to DWI repetition interval.

RESULTS

Electrical activities in sEMG and number of visible SMAMs in DWI showed a strong correlation (ρ = 0.9718). High accordance between sEMG activities and visible SMAMs in DWI in a near-surface region around sEMG electrodes was achieved. Characteristics of sEMG activities were almost similar under varying magnetic field conditions.

CONCLUSION

Visible SMAMs in DWI have shown a close and direct relation to concurrent signals recorded by sEMG. MR-related magnetic fields had no significant effects on findings in sEMG. Hence, appearance of SMAMs in DWI should not be considered as imaging artifact or as effects originating from the special conditions of MR examinations. Spatial and temporal distributions of SMAMs indicate characteristics of spontaneous (microscopic) mechanical muscular action at rest. Therefore, DWI techniques should be considered as non-invasive tools for studying physiology and pathophysiology of spontaneous activities in resting muscle. Magn Reson Med 79:2784-2794, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

Citalopram-induced dyskinesia of the tongue: a video presentation

We describe a 51-year-old man with sudden onset involuntary movements of the tongue 2 weeks after initiation of citalopram. The movements were continuous and isolated to the tongue. Speech was minimally dysarthric. Further examination revealed no abnormalities. Citalopram was continued and spontaneous improvement was noticed in the following weeks. There was complete recovery 5 weeks after symptoms had started. We argue that the involuntary tongue movements were a side effect of citalopram. Furthermore, our patient used concomitant citalopram and methylphenidate, a combination which potentially elicits side effects. We include a video of the tongue movements in this patient.