ODP285 A Case of Encephalitis and Adrenal Insufficiency in a Patient With Panhypopituitarism After COVID-19 Vaccination

BACKGROUND: Since COVID-19 vaccination was introduced, various adverse effects have been linked to the vaccines. In patients with hypopituitarism, adrenal insufficiency due to the side reactions including fever of COVID-19 vaccination is concerned. CLINICAL CASE: A 33-year woman was on medical therapy including hydrocortisone (HC) for panhypopituitarism arising from surgical treatment of a pituitary adenoma in 2006. She received a COVID-19 vaccination on day X-3. On day X-2, she developed fever in the morning and became unconscious in the evening. She was brought to our hospital by her family at night on day X. She had fever of 40.5°C, low blood pressure, and Glasgow Coma Scale (GCS) of 11. Her neck was supple and she had no quadriplegia. A COVID-19 PCR test was negative. Blood tests showed elevated white blood cell count (8900/μL; reference range: 3300–8600/µL) and C-reactive protein (138.3 mg/l; reference range: 0-1.44 mg/l). Blood glucose (81 mg/dL), ACTH (<3. 00 pg/mL; reference range: 7.2–63.3 pg/mL), and cortisol (1.9 μg/dL; reference range: 2.9–19.4 µg/dL) were low. Serum electrolytes were normal. A computed tomography scan showed no abnormality. Adrenal insufficiency was suspected, and she received HC intravenously. Her blood glucose and blood pressure increased, but her disorientation persisted. Lumbar puncture with cerebrospinal fluid (CSF) examination revealed slightly elevated cell counts (8 μ/L; reference range ≤4 μ/L) with average protein and glucose levels. Magnetic resonance imaging (MRI) of the brain revealed abnormal hyperintensity in the splenium of the corpus callosum on diffusion-weighted images and decreased apparent diffusion coefficient in the lesion, suggesting clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS). During her hospital stay, she received a 7-day course of meropenem and acyclovir for suspected meningoencephalitis. Her consciousness disturbance improved to GCS of 15 on day X+1 and her fever decreased on day X+2. HSV and VZV PCR tests were negative on CSF examination, and antibiotics and antivirals were discontinued on day X+7. On day X+8, brain MRI showed complete resolution of the corpus callosum lesion. She discharged on day X+18 without any neurological sequelae. CONCLUSIONS: For most vaccines, the incidence rates of encephalitis are low at 0.1–0.2 per 100,000 vaccinated individuals (1). The present patient developed fever and adrenal insufficiency after COVID-19 vaccination, and her prolonged disturbance of consciousness after HC administration led to the diagnosis of MERS. MERS should be considered in patients with adrenocortical insufficiency who show delayed recovery from unconsciousness with HC administration after COVID-19 vaccination. Reference: (1) Huynh W, Cordato DJ, Kehdi E, Masters LT, Dedousis C. Post-vaccination encephalomyelitis: literature review and illustrative case. J Clin Neurosci. 2008 Dec;15(12): 1315-22. Presentation: No date and time listed