A favorable outcome of intensive immunotherapies for new-onset refractory status epilepticus (NORSE)

Background

New-onset refractory status epilepticus (NORSE) is a newly defined critical disease entity characterized by prolonged periods of refractory epileptic seizure with no readily identifiable cause in otherwise healthy individuals. Its etiology is uncertain, but autoimmune encephalitis is a possible candidate for the underlying cause of this condition. Immunotherapies could be considered for this condition, but its efficacy is not established.

Case presentation

A 31-year-old man with no prior history presented with refractory status epilepticus. His seizure persisted even with multiple anti-epileptic drugs and required prolonged general anesthesia under mechanical ventilation. Magnetic resonance imaging and cerebrospinal fluid did not indicate the cause of seizure, and autoantibodies related to encephalitis were not detected. It was speculated that the patient had occult autoimmune encephalopathy because of its acute-onset clinical course preceded by fever, even without definite evidence of an autoimmune mechanism. The patient received intravenous methylprednisolone, plasma exchange, and intravenous immunoglobulin in succession and manifested a favorable outcome after these treatments.

Conclusion

Our case supports the efficacy of immunotherapies for NORSE even though it does not manifest definite evidence for autoimmune background. Clinicians should consider these immunotherapies for NORSE as early as possible, because this condition is associated with high mortality and morbidity owing to prolonged seizure activity and long-term intensive care including general anesthesia and mechanical ventilation.

Update on juvenile myasthenia gravis

PURPOSE OF REVIEW

Juvenile myasthenia gravis is a relatively rare autoimmune neuromuscular disorder. The pathophysiology of juvenile myasthenia gravis is similar to that of adult myasthenia gravis, though there remain important differences regarding presentation and therapeutic options. We review the pathophysiology, clinical presentation, and treatment options for juvenile myasthenia gravis.

RECENT FINDINGS

Randomized clinical studies of myasthenia gravis have been carried out primarily in adult populations. As juvenile myasthenia gravis is rare, it has been difficult to collect prospective randomized controlled data to evaluate treatment outcomes and efficacy. A recent retrospective series suggests that, as in adult myasthenia gravis, thymectomy is a viable therapeutic option for selected cases of generalized juvenile myasthenia gravis. This is corroborated by the clinical experience of the authors in a referral center with a cohort of patients affected by juvenile myasthenia gravis over a number of years.

SUMMARY

Recent studies illustrate that some, but not all, adult research on myasthenia gravis is applicable to children and adolescents with juvenile myasthenia gravis. Adult research can inform pediatric studies, but should not be regarded as a substitute for dedicated research in those populations.