Ketamine use in refractory status epilepticus associated with anti-NMDA receptor antibody encephalitis.

PURPOSE: Anti-N-methyl-D-aspartate receptor encephalitis (anti-NMDAr encephalitis) is an auto-immune disorder associated with the production of antibodies against NR1 and NR2 sub units of the NMDA receptor. Seizures in this population are reported in up to 50% of cases with status epilepticus being reported in 25% of cases, refractory status epilepticus in 13.8% of cases and super-refractory status epilepticus in 10.2% of cases. Treatment of refractory epileptic activity in this population is not uniform and heterogeneous. METHODS: We present three cases of super refractory status epilepticus in patients with anti-NMDAr encephalitis treated successfully with ketamine, a noncompetitive NMDA receptor antagonist. All patients had failed to improve clinically on multiple anti-convulsants and immunotherapy prior to initiation of ketamine therapy. RESULTS: In all three cases, administration of a load followed by maintenance infusion (0.05 mg/kg/min infusion) of ketamine yielded clinical and/or electrographic seizure cessation in less than 48 h. Patients were treated for a heterogeneous duration although ultimately, epilepsy outcomes were favorable from a seizure freedom standpoint. Earlier treatments with ketamine were associated with better epilepsy outcomes in this case series. CONCLUSIONS: Ketamine may be a useful adjunct treatment in super-refractory status epilepticus in patients with NMDAr encephalitis.

A prospective study of benign fasciculation syndrome and anxiety.

INTRODUCTION: Benign fasciculations are common. Despite the favorable prognosis of benign fasciculation syndrome (BFS), patients are often anxious about their symptoms. In this study, we prospectively followed 35 patients with BFS over a 24-month period. METHODS: We conducted serial questionnaires to assess anxiety, associated symptoms, and duration. RESULTS: 71.4% of patients were men, and 34.4% were employed in the medical field. Most reported anxiety, but only 14% were anxious as measured by the Zung self-rating anxiety scale. Fasciculations were most common in the calves and persisted in 93% of patients. Anxiety levels did not change over time. Associated symptoms (subjective weakness, sensory symptoms, and cramps) were common and resolved to varying degrees. No patients developed motor neuron disease. DISCUSSION: BFS is a benign disorder that usually persists over time. Commonly associated symptoms include subjective weakness, sensory symptoms, and cramps. BFS is usually not associated with pathologic anxiety. Muscle Nerve 58:852-854, 2018.

Radiation-Induced Painful Neurogenic Hypertrophy Treated With Botulinum Toxin A.

Painful neurogenic hypertrophy is a rare complication of radiation therapy. We report a 27-year-old woman with a history of adenoid cystic carcinoma of the submandibular gland presented with painful twitching of her left shoulder. Electrodiagnostic studies were consistent with a diagnosis of radiation-induced spinal accessory nerve hyperactivity. The patient failed conventional medical therapy. She was treated with an injection of botulinum toxin A, and within 1 month experienced significant relief of symptoms. We thus conclude that Botulinum toxin is a therapeutic option for the pain associated with radiation-induced peripheral nerve hyperactivity.