Encephalitis is a rare neurological disease which a viral infection or an autoinmune disorder can cause. Regardless of the etiology, the presentation is widely varied with symptoms stemming from headaches to hallucinations to cardiac dysrhythmias. A diagnosis is most commonly reached through an elimination process, due to the vague nature of the symptoms. The purpose of this case is to showcase a patient in which the classical imaging findings of an autoimmune encephailits were absent, in favor of an atypical presentation. A 19-year-old female began with an episode of auditory hallucinations accompanied by a headache, all resolved without treatment. A week later she developed irrational fear as well as nausea and seizures. Visual hallucinations followed, with an altered state of consciousness, memory loss, and a fever of over 100°F. She was admitted into emergency care, where a head CT scan was performed, which revealed a generalized and diffuse decrease in density of the white matter, corresponding to cerebral edema. Spinal fluid revealed a high protein count, with normal glucose and white blood cell count. An electroencephalogram resulted in the presence of theta brain waves with the absence of an epileptogenic area, which indicates a disfunctional neurological state. The patient developed respiratory distress requiring intubation and was admitted into the intensive care unit with a new treatment of antiviral medicine, with the new diagnostic suspicion of encephalitis. A contrast-enhanced thoracoabdominal CT was performed, which revealed a right adnexal theratoma, guiding the diagnostic suspicion to an anti-NMDA induced encephalitis, for which a brain contrast-enhanced MRI was performed, with no classical findings present such as hippocampal atrophy and temporal lobe hyperintensity; instead the T2-based sequences showed cystic oval lesions in the frontal, temporal and occipital lobe, as well as diffuse hyperintensity of white matter, susceptibility weighted sequences showed focal round hypointesities corresponding to microhemorrhages distributed through the entirety of the white matter, and the gadolinium-enhanced sequence showed avid enhancement of the cystic lesions. A second spinal fluid test revealed antibodies against NMDA receptors and immunoglobulin treatment was administered with a poor response from the patient who presented heart failure shortly after and died. Read More

Meeting name: SPR 2024 Annual Meeting & Postgraduate Course , 2024

Authors: Reyna De La Garza Karla, Salinas Puente Estefany, Mercado Flores Mariana, Rodríguez Garza Claudia, Maya Garcia Haziel, Montemayor Martinez Alberto

Keywords: encephalitis, autoimmune, neuroradiology