P2.K219: Consider Acute Disseminated Encephalomyelitis in a Child with Acute Neurological Deficits

Introduction: Acute Disseminated Encephalomyelitis (ADEM) is an autoimmune encephalitis that can present in numerous ways including stroke-like symptoms, seizure activity, or acute neuropsychiatric changes. The prevalence of ADEM in the United States is rare as only 0.2-0.4/100,000 children are diagnosed annually. ADEM has been associated with preceding infections or vaccinations, so the current proposed etiology is that ADEM arises as a post-infectious sequelae or post-vaccination aberrant immunological reaction. Our case is unique in that the patient had a significant family history of autoimmune disease, but there are very few cases in the literature that illustrate family history of autoimmune disease as a risk factor for ADEM.

Case Description: 6-year-old female with a past medical history of speech delay and three isolated febrile seizures not treated with antiepileptic therapy presented to the emergency department with acute neurological deficits and altered mental status. Within hours of admission, the patient developed global aphasia, left sided facial paralysis, and right sided hemiparesis. MRI was normal, EEG showed focal left hemisphere slowing, and blood, urine, and cerebrospinal fluid cultures ruled out infectious etiologies. An autoimmune encephalitis panel was unremarkable. Due to the EEG findings and a persistent Todd’s paralysis and encephalopathy, the patient was placed on levetiracetam and lacosamide. Repeat brain MRI three days later showed interval development of gyriform/cortical diffusion restriction involving the left paracentral lobule. Neurology was concerned for ADEM and IVIG was given with resultant slow progressive improvement of the global aphasia and left facial paralysis. The patient’s right sided hemiplegia partially resolved, but right lower extremity weakness persisted.

Discussion: The patient has a significant family history of systemic lupus erythematosus as her mother, maternal aunt, and maternal grandmother are all affected. Rheumatology was consulted and work up did not support a diagnosis of Lupus, Sjogren's, or Mixed Connective Tissue disease at this time.
The current recommendation is to use IV steroids as first line treatment, but our patient received IVIG 2 grams/kilogram over 2 days because results from an extensive workup for viral and bacterial infectious etiologies had not ruled out infection as the cause of presentation.

Conclusion: ADEM should be readily considered as a differential diagnosis for pediatric patients with acute neurological deficits and/or psychiatric alterations not explained by an infectious or autoimmune etiology. Severe illness is associated with prolonged and possible permanent deficits, so treatment should be swift following possible autoimmune encephalitis workup.