Myoclonus-Ataxia Syndrome Associated with COVID-19.

Neurological manifestations of coronavirus disease (COVID-19) have increasingly been reported since the onset of the pandemic. Herein, we report a relatively new presentation. A patient in the convalescence period following a febrile illness with lower respiratory tract infection (fever, myalgia, nonproductive cough) presented with generalized disabling myoclonus, which is phenotypically suggestive of brainstem origin, along with additional truncal cerebellar ataxia. His neurology work-ups, such as brain MRI, electroencephalography, serum autoimmune and paraneoplastic antibody testing, were normal. His CT chest scan revealed right lower lung infiltrates, and serological and other laboratory testing did not show evidence of active infection. COVID-19 titers turned out to be strongly positive, suggestive of post-COVID-19 lung sequelae. He responded partially to antimyoclonic drugs and fully to a course of steroids, suggesting a para- or postinfectious immune-mediated pathophysiology. Myoclonusataxia syndrome appears to be a neurological manifestation of COVID-19 infection, and knowledge regarding this phenomenon should be increased among clinicians for better patient care in a pandemic situation.

Interictal regional paroxysmal fast activity on scalp EEG is common in patients with underlying gliosis.

OBJECTIVE: Interictal regional paroxysmal fast activity (RPFA) on scalp EEG is common in patients with focal cortical dysplasia (FCD). Little data exists regarding the presence of RPFA in other etiologies. METHODS: We studied the association between RPFA and etiology on MRI in patients with drug resistant focal epilepsy undergoing presurgical evaluation in 2011. RPFA was defined as ≥3 consecutive spikes with a frequency of ≥10 Hz lasting ≥300 ms but <4 s. RESULTS: 626 patients fulfilled the inclusion criteria. Of these, 138 (22%) patients had RPFA while rest had other interictal epileptiform discharges (IEDs). RPFA was located at posterior head region in 52.2% patients, frontal regions in 24.6% patients and over temporal regions in 17.4% patients. Focal gliosis (61, 44%) and FCD (27, 19%) were common etiologies in patients with RPFA. Compared to patients with other IEDs, patients with RPFA were more likely to have focal gliosis (61/138 vs. 39/488; p < 0.0001) or FCD (27/138 vs 37/488; p < 0.001) as the etiology of epilepsy. CONCLUSION: In developing countries, focal gliosis is more common than FCD as the underlying etiology in patients with RPFA on scalp EEG. SIGNIFICANCE: Focal gliosis should be considered as one of the common substrate for RPFA on scalp EEG.

Pregabalin Toxicity Manifesting as Reversible Encephalopathy With Continuous Triphasic Waves in Electroencephalogram.

A 74-year-old man with peripheral neuropathy due to diabetes presented with deliberate ingestion of 450 mg of pregabalin (PBG) over a period of 8 hours followed by altered mental status. A bedside electroencephalogram was performed to rule out nonconvulsive status epilepticus, which showed continuous triphasic waves (TWs) with slow background activity. He recovered after 48 hours of stopping PBG, and his repeat electroencephalogram after 72 hours did not show any TWs. We present a rare case of PBG-induced TWs thereby highlighting the extent of the etiologic spectrum of TWs and discussing the literature related to this association.

Carbamazepine Toxicity-Induced Spindle Coma: A Novel Case Report.

A 9-year-old girl presented with alleged history of deliberate ingestion of 4 g of carbamazepine, following which she became comatose. A bedside electroencephalogram (EEG) was performed to rule out nonconvulsive status epilepticus, which showed presence of spindle coma (SC), not reactive to noxious stimuli. Following hemodialysis, a second EEG showed absence of SC and complete clinical recovery. We present this unique case of carbamazepine-induced SC, thereby highlighting the extent of the etiologic spectrum of SC and discussing the literature related to this association.

Supra-recommendation Treatment of Super-refractory Status Epilepticus.

A 28-year old female was admitted with recurrent seizures following 2 days of febrile illness, after which she developed status epilepticus. Midazolam and later thiopentone infusions were started after failure of regular intravenous antiepileptics. Burst suppression was achieved at doses of 3 mg/kg/hr for midazolam and 6 mg/kg/hr of thiopentone. Adjunctive medications included methylprednisolone, intravenous immunoglobulin and acyclovir. Imaging and biochemical parameters were normal. She required 3 cycles of midazolam and 2 cycles of thiopentone for complete cessation of seizures. She recovered with mild attentional and recent memory deficits on follow up. Treatment of super-refractory status epilepticus requires individualized regimens and may need doses beyond conventional limits. To the best of our knowledge, there is no such reported case from India.

Clinico-radiological spectrum and outcome in idiopathic hypertrophic pachymeningitis.

OBJECTIVE: To elucidate the clinico-radiological features, treatment response and outcome of a large cohort of patients (n=20) with idiopathic hypertrophic pachymeningitis (IHP) and to examine if any of these features could differentiate between IHP and secondary causes of hypertrophic pachymeningitis (SHP). METHODS: 20 patients with IHP diagnosed between 1998 and 2009 formed the study cohort. We adopted a validated clinical score to quantitatively assess and document their neurological disability and to compare their pre- and post-treatment outcomes. Appropriate statistical analysis was done to look for any clinical and/or radiological features to differentiate IHP from SHP. RESULTS: Out of the twenty eight consecutive patients with pachymeningitis, 20 were having IHP and 8 were having SHP (Tuberculosis-5, Sarcoidosis-2, Wegener's granulomatosis-1). In IHP, headache and visual symptoms dominated the clinical symptomatology (80% and 75%). In MRI, the peripheral pattern of contrast enhancement was more common with IHP (p=0.03). The posterior falx and tentorium showing a hypointense center ("fibrosis") and enhancing periphery ("active inflammation") together mimicking "Eiffel-by-night" sign was found to be more commonly associated with IHP (60% vs 12.5%, p=0.03). Biopsy was done in 9 patients. At a mean follow-up of 51 months (range 24-144 months), the mean pretreatment clinical score improved from 6.55 to 1.80 in 20 patients with IHP (p<0.001). CONCLUSIONS: Our data on the largest cohort of patients with IHP would shed light into its clinico-radiological spectrum, treatment and outcome. The prognosis is satisfactory if managed appropriately. We have highlighted the role of MRI in differentiating between IHP and other causes of SHP.

What does "subclinical rhythmic electrographic discharge of adults" in EEG signify?

Subclinical rhythmic electrographic discharge of adults (SREDA) is the rarest benign epileptiform variant. It is an established EEG phenomenon that when present may cause confusion with an epileptic discharge for those unfamiliar with the entity. An electronic term search was performed on all EEG reports to identify those records reported as showing SREDA and other benign variants. Serial EEG reports of 5,200 subjects who underwent EEG through our EEG laboratory services between January 2001 and December 2009 were thus scrutinized, and their clinical profile and follow-up data were obtained. A total of four subjects had SREDA (0.07%) in their EEG, and their mean age was 53.7 years. The duration of SREDA ranged from 10 to 60 seconds. SREDA was not associated with any clinical seizures during recording. Two patients remained asymptomatic on long-term follow-up. One patient was found to have idiopathic generalized epilepsy and another patient had Alzheimer disease during the follow-up. Mere presence of SREDA may not have any clinical significance at one point of time. The authors have also highlighted the possible pathophysiological basis of SREDA. Many features of SREDA still remain unresolved: why is it more common in the elderly population, why is its spatial distribution centered over temporoparietal region, why it appears mostly in wakefulness, and what is its pathogenesis? It would be worthwhile if compilation of cases reported world over are performed and further analyzed to reach at a common conclusion on its varied clinical presentations and EEG features.

Long-term outcome and prognosis of patients with emergent periodic lateralized epileptiform discharges (ePLEDs).

PURPOSE: Emergent EEG (eEEG) is an EEG performed on a non-elective basis upon request from a clinician for a seemingly emergency indication. Little is known about the long-term prognosis of patients with emergent periodic lateralized epileptiform discharges (ePLEDs). METHODS: We analyzed the EEG and clinical records of patients with ePLEDs from January 2002 to December 2008. RESULTS: Out of 1948 eEEGs, 79 (4%) patients had ePLEDs. Sixty-three patients had ePLEDs and 16 had eBiPLEDs (emergent bilateral periodic lateralized epileptiform discharges). The etiology of ePLEDs was CNS infection and inflammation (35.4%), stroke (32.9%), and metabolic encephalopathy (11.4%). Of the surviving 52 (65.8%) patients with ePLEDs, 34 (65.4%) had persistent seizures during a mean follow-up of 28 months (range 12-72 months). Seizure as the initial presentation was more commonly seen in children as compared to adults (64% versus 31%, p=0.005). CNS infection and inflammation were also seen more frequently in the pediatric age group (50% versus 27%, p=0.04). At follow-up, patients with eBiPLEDs had more seizures than patients with ePLEDs (87.5% versus 61.3%). CONCLUSION: ePLEDs is associated with significant morbidity and mortality. However, the etiology of ePLEDs and brain dysfunction will influence the long-term outcome. This information is invaluable for prognostication and underscores the importance of rigorous management of patients with ePLEDs.

An audit of the presurgical evaluation and patient selection for extratemporal resective epilepsy surgery in a resource-poor country.

PURPOSE: The selection of ideal candidates for extratemporal resective epilepsy surgery is a challenge in resource-poor countries because of the limited presurgical diagnostic facilities and their affordability. To audit the presurgical evaluation strategy and selection for extratemporal resective epilepsy surgery in a resource-poor region. METHODS: From the prospective database maintained at an epilepsy surgery center in southern India, we reviewed the data of consecutive patients who underwent presurgical evaluation from January 2005 through December 2008 for antiepileptic drug-resistant focal epilepsies emanating from the frontal, parietal and occipital lobes. Out of 285 patients, only 71 (24.9%) underwent resective surgery; the remaining 214 (75.1%) patients could not be selected for surgery. We inquired the reasons for their exclusion from surgery. RESULTS: The difference in the rates of seizure-free outcome between surgical and non-surgical groups was highly significant (73.2% vs. 7.7%, P<0.0005). The major reasons for exclusion from surgery were normal MRI in 107 (50%), inability to afford invasive EEG monitoring in 40 (18.7%) and lesion location adjacent to eloquent cortical areas in 27 (12.6%) patients. While clustering of seizures and presence of preoperative neurological deficits favored surgical selection, the presence of secondary generalized seizures and discordant interictal epileptiform abnormalities were associated with exclusion from surgery. CONCLUSIONS: We conclude that, in a resource-poor country, ideal candidates for extratemporal resective epilepsy surgery are those with well-circumscribed lesions not adjoining eloquent cortical areas. In such patients, concordant EEG findings and absence of preoperative secondary generalized seizures reinforce selection for surgery.