Unexpected worsening of progressive multifocal leucoencephalopathy following COVID-19 pneumonia

Journal of NeuroVirology - Progressive multifocal leucoencephalopathy is a serious side effect of natalizumab, a humanized monoclonal antibody approved for the treatment of multiple...     

Usefulness of transcranial magnetic stimulation to predict the development of reflex sympathetic dystrophy poststroke: a pilot study

OBJECTIVE: To investigate the predictive value of transcranial magnetic stimulation (TMS) for the development of reflex sympathetic dystrophy (RSD) poststroke. DESIGN: Blind clinical assessment of 2 groups of stroke patients defined on the basis of absent or preserved motor evoked potentials (MEPs) on the affected side. SETTING: Stroke rehabilitation center. PATIENTS: Twenty stroke patients between the ages of 41 and 85 years, undergoing rehabilitation. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: MEPs from upper limbs 30 days poststroke, Motricity Index, and scoring of RSD using the Enjalbert Scale 73 days poststroke. RESULTS: A good correlation was found between Motricity Index and TMS results (P<.01). Average Enjalbert scores were significantly different between the 2 groups (P=.03). No significant correlation was found between Enjalbert scores and the Motricity Index. CONCLUSIONS: Although no significant relationship was found between upper-limb motor impairment and intensity of RSD 10 weeks after stroke, the TMS responses permitted the early categorization of patients into 2 groups that developed significantly different average Enjalbert scores 1 to 2 months later when this clinical condition was fully developed.     

Anterior spinal artery syndrome after aortic surgery in a child

Anterior spinal artery syndrome is rare in children. In adults, where it is observed most frequently after resection of thoracoabdominal aortic aneurysms, spinal magnetic resonance imaging is considered the first-line investigation to confirm the clinical diagnosis. A 3-year-old male who presented with this syndrome after palliative cardiac surgery for a complex cardiac malformation associated with aortic coarctation is presented. Clinical diagnosis of anterior horn cell impairment below the L2 level was confirmed by electromyography and F-wave studies. Sparing of dorsal sensory tracts was documented by normal somatosensory-evoked potentials, which confirmed the anterior localization of the lesion. Spinal magnetic resonance imaging performed on day 15 and day 105 after surgery was normal. Neurologic deficits, including flaccid paraplegia, remained stable except for the reappearance of patellar reflexes on day 83. Neurophysiologic conduction studies were consistent with lower motoneuron loss. In this patient, magnetic resonance imaging was less sensitive in demonstrating spinal cord lesion than clinical neurophysiology. Somatosensory-evoked potentials failed to detect the insult. Prevention may therefore require other neurophysiologic monitoring techniques.     

Transcranial magnetic stimulation and other evoked potentials in pediatric multiple sclerosis

In children, multiple sclerosis is rare and has some clinical and paraclinical differences compared with adults. The assessment of corticospinal motor tracts is expected to be relevant because of their frequent early involvement in this disease. Reported are the results of transcranial magnetic stimulation in two children who presented at 12 and 9 years of age with clinically probable and definite multiple sclerosis, respectively. In Patient 1 the excitatory cortical threshold for the upper limbs was abnormally raised. In Patient 2 the latency of the motor-evoked potentials was considerably increased for the right tibialis anterior muscle, with a slowing of the central conduction time. Although these abnormalities may be consistent with central conduction impairment, they may alternatively suggest early axonal damage because irreversible axonal lesions occurring at the onset of the disease have recently been reported. Testing of central motor tracts, in addition to visual, auditory, and somatosensory pathways, therefore appears appropriate in the multimodal assessment of pediatric patients with suspected multiple sclerosis.     

The H reflex as a diagnostic tool for Miller Fisher syndrome in pediatric patients

Miller Fisher syndrome (MFS) is characterized by gait ataxia, external ophthalmoplegia and areflexia. Immunohistochemical studies suggest a pathophysiological role for anti-GQ1b antibodies at the paranodal regions of the oculomotor nerves, at some neurons of the dorsal root ganglia (DRG) and at motor nerve terminals. The variability of abnormal electrophysiological findings reported is significant. Nerve conduction studies, H reflex and F waves were performed in three pediatric patients with MFS. The H reflex was absent in all three patients. It was the sole abnormality in two patients whereas the third patient also had extended motor and sensory nerve conduction impairments. The transient character of this isolated absence has been confirmed in one patient. These data point to a proximal demyelinating process near the DRG. This may involve selective demyelination of Ia spinocerebellar afferent fibers originating in muscle spindles. In a pediatric practice, the H reflex seems to be a useful tool in the diagnostic approach to MFS.     

Lower limb monoplegia and dissociated hypoesthesia after peridural anesthesia]

Neurological sequelae reported after epidural anesthesia include epidural hematoma, spinal cord ischemic injury and lumbosacral nerve root injury. We describe here a case of monoplegia of the right lower limb associated with an ipsilateral loss of perception of pain and temperature following an epidural anesthesia. MRI was compatible with a right centrolateral infarction in the gray matter of the spinal cord below D8. Hypotension, vascular spasm, trauma, arteriosclerosis, pressure increase in the epidural space are potential causative mechanisms. Unilateral symptoms might result from injury to a sulcocommissural artery or an anterior spinal artery when duplicated.