Fabry disease patients have an increased risk of stroke in the COVID-19 ERA. A hypothesis.

Stroke is a severe and frequent complication of Fabry disease (FD), affecting both males and females. Cerebrovascular complications are the end result of multiple and complex pathophysiology mechanisms involving endothelial dysfunction and activation, development of chronic inflammatory cascades leading to a prothrombotic state in addition to cardioembolic stroke due to cardiomyopathy and arrhythmias. The recent coronavirus disease 2019 outbreak share many overlapping deleterious pathogenic mechanisms with those of FD and therefore we analyze the available information regarding the pathophysiology mechanisms of both disorders and hypothesize that there is a markedly increased risk of ischemic and hemorrhagic cerebrovascular complications in Fabry patients suffering from concomitant SARS-CoV-2 infections.

Nonconvulsive status epilepticus in the elderly: a case-control study.

BACKGROUND: Nonconvulsive status epilepticus (NCSE) is a usually underdiagnosed and potentially treatable cause of altered awareness in the elderly. To assess etiologies, associations with other medical problems, and prognosis of NCSE in a population aged >75 years we performed a nested case-control study. METHODS: We retrospectively evaluated the clinical manifestations and EEG findings in 19 consecutive elderly patients (mean age 83.3 years) presenting with NCSE and compared them with 34 elderly patients (mean age 83.3 years) with altered mental status but without EEG evidence of NCSE. The variables compared included brain lesions on CT or MRI, number of concomitant chronic active diseases, previous neurological disorders, acute medical problems, the use and withdrawal of medications, and outcome. Statistical analysis was performed using chi-square test, t-test, Fisher's exact two-tailed test, and Wilcoxon rank sum test. RESULTS: The etiology of NCSE was epilepsy in 2, acute medical disorders in 14, and a cryptogenic cause in 4. The NCSE group had a more frequent history of epilepsy, 35% versus 8.8% (p = 0.028); tramadol use, 31% versus 0% (p = 0.00151); longer hospitalization, 25 days versus 7 days (p = 0.0004); and unfavorable outcome, 50% versus 5.8% (p = 0.00031). No significant differences were found in the other variables. Unfavorable outcome was associated with a higher number of comorbidities (>2) and to a severely altered mental status. CONCLUSIONS: NCSE is a serious cause of altered mental status in the elderly. Although its direct role in brain damage is controversial, elderly patients with NCSE have higher morbidity and worst prognosis than those with altered mental status without NCSE.

Hemicránea atípica como forma de presentación de una cefalea centinela / Atypical hemicrania as a presenting symptom of a sentinel headache

No disponible

Playing harp, another unusual task-specific dystonia.

Herein we report a task-specific dystonia in a 48-year-old woman, with an unusual association between a familial harp-playing dystonia and essential tremor.

Thyrotoxic periodic paralysis in caucasians. Report of 8 cases.

BACKGROUND: Periodic paralysis is a well known complication of thytotoxicosis in Chinese and Japanese patients, but has been considered extremely rare in caucasians. PATIENTS AND METHODS: Between 1991 and 1996, we admitted 8 caucasian patients to our Hospital due to thyrotoxic periodic paralysis. We retrospectively analysed their clinical manifestations. RESULTS: All the patients were males. Their attacks started at night or early after awakening, frequently triggered by a high carbohydrate diet and physical exertion. Myalgias and flaccid weakness predominated over proximal leg muscles, sparing bulbar and respiratory musculature. Reflexes were brisk at the onset of the attack and reduced or absent during the course of the episode. Prior to diagnosis patients presented 1-5 attacks of thyrotoxic periodic paralysis each lasting 1-96 hours. Hypokalemia was documented in 6 patients. The episodes of periodic paralysis led to the diagnosis of a previously unsuspected thyrotoxicosis in 6 patients. In the other 2 patients the diagnosis of the thyroid dysfunction preceded the periodic paralysis. Attacks resolved after treatment of the hyperthyroid state. CONCLUSIONS: Thyrotoxic periodic paralysis is an under-diagnosed but probably frequent complication of hyperthyroidism in caucasians. Early recognition of the attacks is essential to investigate and treat the underlying thyroid dysfucntion whose symptoms are usually mild. The episodes of periodic paralysis resolve with the correction of the hyperthyroidism.

Parálisis periódica tirotóxica en sujetos de raza blanca. Presentación de 8 casos / Thyrotoxic periodic paralysis in caucasians. Report of 8 cases

Fundamento: La parálisis periódica es una frecuente complicación de la tirotoxicosis en pacientes chinos y japoneses, pero ha sido considerada como una rara complicación en pacientes caucásicos. Pacientes y métodos: Hemos analizado retrospectivamente las características clínicas de 8 pacientes caucásicos con parálisis periódica tirotóxica, internados entre los años 1991-1996. Resultados: Todos los pacientes eran varones. Los ataques ocurrieron durante la noche o las primeras horas de la mañana, frecuentemente precipitados por la ingestión abundante de hidratos de carbono o por ejercicio. Mialgias y debilidad proximal de los miembros inferiores fueron los síntomas más frecuentes. La musculatura respiratoria y la de los pares craneales no resultó afectada. Los reflejos se hallaron hiperactivos al inicio del ataque y reducidos posteriormente. Antes del diagnóstico los pacientes habían sufrido 1-5 ataques de parálisis periódica tirotóxica que duraron 1-96 h. Se constató hipocaliemia en 6 pacientes. Los episodios de parálisis periódica permitieron sospechar hipertiroidismo en 6 pacientes. En los otros 2 pacientes el diagnóstico de la alteración endocrinológica precedió a la parálisis periódica. Los ataques desaparecieron con la corrección de la tirotoxicosis. Conclusiones: La parálisis periódica tirotóxica es una complicación subdiagnosticada pero probablemente frecuente en pacientes caucásicos. El reconocimiento precoz de los ataques es esencial para investigar y tratar el hipertiroidismo, cuyos síntomas suelen ser leves. Los episodios de parálisis periódica tirotóxica no se repiten al controlar el hipertiroidismo. (AU)

Amyotrophic lateral sclerosis IgG-treated neuromuscular junctions develop sensitivity to L-type calcium channel blocker.

In order to search for early changes induced by the application of human immunoglobulin G (IgG) on motor nerve terminals, IgG from patients with amyotrophic lateral sclerosis (ALS) and control subjects was injected subcutaneously into the levator auris muscle of mice. A week or a month after the last injection, endplate potentials were recorded. No changes in quantal content of transmitter release were observed. In control and ALS IgG-treated muscles, neurotransmitter release remained sensitive to P/Q-type and insensitive to N-type voltage-sensitive calcium channel (VSCC) blockers as in untreated muscles. In contrast, IgG from 5 of 8 different ALS patients induced a significant reduction in quantal content of the evoked response after incubation with nitrendipine, indicating that a novel sensitivity to this calcium channel blocker appears in these motor nerve terminals. These results indicate that ALS IgG induces plastic changes at nerve terminals. The expression of transmitter release coupled to L-type VSCC indicate that ALS IgGs are capable of inducing plastic changes at the nerve terminals that may participate in the process leading to neuronal death.

Nerve biopsy in children with severe Guillain-Barré syndrome and inexcitable motor nerves.

The presence of inexcitable motor nerves early in the course of Guillain-Barré syndrome (GBS) identifies a subgroup of patients with more severe disease and delayed recovery. How frequently these electrodiagnostic findings reflect a primary axonal attack ("axonal" GBS) is controversial. We present two children with severe acute GBS, delayed recovery, and residual disability despite early treatment with human immunoglobulin. They had inexcitable motor nerves at days 6 and 7, and profuse fibrillations and positive waves on subsequent studies. Clinically and electrodiagnostically, both children's disease resembled the acute motor-sensory axonal variant of GBS (AMSAN). Sensory and motor nerve biopsies revealed severe macrophage-associated demyelination with axonal degeneration of variable severity. We conclude that clinical and electrodiagnostic features cannot discriminate between the "axonal" and demyelinating GBS. Early and severe demyelination with secondary axonal damage may mimic clinically and electrophysiologically the AMSAN variant of GBS.

Spastic paraparesis and sensory neuropathy.

A 12-year-old developed a slowly progressive spastic gait at the age of 3. A marked loss of pain and temperature sensations led to a mutilating acropathy starting at age 5. Electrodiagnostic studies revealed a symmetric, axonal, predominantly sensory neuropathy, and magnetic resonance imaging ruled out compression of spinal cord. Sural nerve biopsy disclosed a predominant involvement of unmyelinated and a global loss of myelinated fibers, particularly larger ones. Clinical, electrodiagnostic and pathological findings of this case most likely represent an example of the "Cavanagh's variant", an unusual but distinct entity within the hereditary sensory and autonomic neuropathies.

Severe Guillain-Barré syndrome in childhood treated with human immune globulin.

Thirteen children with severe Guillain-Barré syndrome were treated with human immune globulin. Patients received a mean total dose of 1.9 gm/kg of human immune globulin for 2 or 5 days. To evaluate the relationship between the response to human immune globulin and electrodiagnostic findings, we compared the clinical outcome of 3 groups of children. The first group consisted of 9 children with electrophysiologic evidence of a mean amplitude of the compound motor action potentials larger than 10% of the lower limit of normal. The second group of 4 children had inexcitable motor nerves. Children in the second group required longer periods to improve one functional grade (mean 67.3 days vs 18.8 days) and to reach grade 2 (219 days vs 32.7 days). Moreover, children in the second group were more disabled after 3 and 6 months, and they all remained with distal atrophy and weakness after 7 months of follow-up. Furthermore, the outcome of children in the second group was no different from that of a historic control of 5 untreated children with severe Guillain-Barré syndrome and similar electrophysiologic findings. Human immune globulin treatment in children with severe Guillain-Barré syndrome is safe, easy to administer, and does not increase the number of relapses. Nevertheless, it does not seem to benefit children with low mean compound motor action potential amplitude.

Acute "axonal" Guillain-Barré syndrome in childhood.

We identified 5 of 44 consecutive children (11%) with Guillain-Barré syndrome who had electrophysiologic evidence of severe reduction of the mean amplitude of the compound motor action potentials (mean CMAP amplitude < 10% of lower limit of normal). EMG studies revealed profuse fibrillation activity in distal and proximal muscles after 2 weeks of onset. We compared this group with 16 consecutive children with GBS prospectively evaluated over 1 year, all of whom presented a mean CMAP amplitude > 10% of lower limit of normal. Children in the first group were more likely to require assisted ventilation (60% vs. 6.2%) and were more frequently quadriplegic at the peak of their disability (80% vs. 18.7%). They also required longer periods to improve one functional grade (mean 63.6 days vs. 16.6 days) and to become ambulatory (mean 156 days vs. 17.6 days). Moreover, only the children in the first group had distal atrophy of four limbs after 1 year of follow-up. Severe reduction of the mean amplitude of the CMAPs in children with GBS identifies a subgroup of patients with axonal damage that produces more severe weakness and delayed recovery.

Effects of different sensory inputs on the median-derived somatosensory evoked potential.

We studied the effect of a variety of "interfering" stimuli on the median-derived somatosensory evoked potentials recorded over Erb's point, cervical spine, and scalp. We found that the amplitude of N20 and P27 recorded over the scalp was attenuated by active movement, vibration, and tactile stimulation of the ipsilateral hand but not by passive movement. Cervical and peripheral responses were unaffected. The pathophysiologic basis and clinical significance of these findings are discussed.

Recovery of peripheral and central responses to median nerve stimulation.

We recorded the responses to paired stimuli delivered to the median nerve at the wrist in 8 healthy adult volunteers, in order to characterize the recovery of function after a single conditioning stimulus. Responses were recorded over the nerve at the ipsilateral elbow and in the Erb's point region, over the second cervical spinous process, and over the contralateral 'hand area' of the scalp. The data from 1 subject were discarded because of possible artifactual contamination. In the others, the peripheral responses recovered both in latency and amplitude over a time period that accorded with previously published studies. We found, however, that the recovery periods for latency and amplitude of the responses recorded over the spine and scalp were prolonged compared with the corresponding values for the peripheral responses. Except for the responses recorded over the scalp, the recovery of amplitude either preceded or occurred at the same time as latency. By contrast, for the responses recorded over the scalp, there was a delay in the recovery of amplitude compared with latency. The differences in recovery period that we found at different levels of the nervous system are presumably related to structural and electrophysiological differences in afferent pathways, the presence of interposed synapses, and the intrinsic refractory properties of central neuronal populations.