Delayed encephalopathy after COVID-19: A case series of six patients.

RATIONALE: Acute encephalopathy is a severe neurological complication of coronavirus disease 2019 (COVID-19). Most cases of acute encephalopathy associated with COVID-19 occur within several weeks of COVID-19 onset. We describe a case series of 6 patients who developed delayed encephalopathy (DE) after COVID-19. PATIENT CONCERNS AND DIAGNOSES: We evaluated patients who recovered from COVID-19 and showed acute disturbance of consciousness or focal neurological deficits without recurrence of pneumonitis. Six patients, 2 females and 4 males, with ages ranging from 65 to 83 years were included. Durations of hospitalization due to COVID-19 were between 25 and 44 days. The severity of COVID-19 was moderate in 5 and severe in 1 patient. Patients were rehospitalized for acute disturbance of consciousness concomitant with postural tremor and, abnormal behavior, hemiplegia, aphasia, or apraxia between 34 and 67 days after the onset of COVID-19. Chest computed tomography showed no exacerbation of pneumonitis. Brain magnetic resonance imaging showed no specific findings except in 1 patient with an acute lacunar infarction. Electroencephalogram demonstrated diffuse slowing in all patients. Repeat electroencephalogram after recovery from encephalopathy demonstrated normal in all patients. One of the 6 patients had cerebrospinal fluid (CSF) pleocytosis. CSF protein levels were elevated in all patients, ranging from 51 to 115 mg/dL. CSF interleukin-6 levels ranged from 2.9 to 10.9 pg/mL. The immunoglobulin index was 0.39 to 0.44. Qlim(alb) < QAlb indicating dysfunction of the blood-brain barrier was observed in all patients. Severe acute respiratory syndrome coronavirus 2 reverse transcription polymerase chain reaction of CSF was negative in all patients. Neuronal autoantibodies were absent in serum and CSF. INTERVENTIONS AND OUTCOMES: Immunotherapy including steroid pulses was administered to 3 patients; however, symptoms of encephalopathy resolved within several days in all patients, regardless of treatment with immunotherapy, and their consciousness levels were recovered fully. Notably, postural tremor remained for 2 weeks to 7 months. LESSONS: In our patients, DE after COVID-19 was characterized by symptoms of acute encephalopathy accompanied with tremor in the absence of worsening pneumonitis after the fourth week of COVID-19 onset. Our findings indicate blood-brain barrier dysfunction may contribute to the pathogenesis of DE after COVID-19.

Acute autoimmune transverse myelitis following COVID-19 vaccination: A case report.

RATIONALE: Transverse myelitis is an infectious or noninfectious inflammatory spinal cord syndrome. We report a rare case of transverse myelitis following vaccination against COVID-19. PATIENT CONCERNS: A 70-year-old male presented with progressive sensorimotor dysfunction of the bilateral lower limbs 7 days after receiving the mRNA-1273 vaccine against COVID-19. Spinal magnetic resonance imaging revealed intramedullary lesions with gadolinium enhancement on the Th1/2 and Th5/6 vertebral levels. Cerebrospinal fluid (CSF) testing showed a mildly increased level of total protein and positive oligoclonal bands (OCB). DIAGNOSIS: The patient was diagnosed with acute transverse myelitis. INTERVENTION: The patient received 5 days of intravenous methylprednisolone pulse (1000 mg/day) followed by oral prednisolone (30 mg/day with gradual tapering). OUTCOMES: The patient fully recovered from muscle weakness of the lower limbs. He was discharged from our hospital and able to independently walk without unsteadiness. LESSON: This is a rare case of transverse myelitis following COVID-19 vaccination. Positive OCB in CSF in the present case highlights the possibility of autoimmune processes, including polyclonal activation of B lymphocytes, following vaccination.

COVID-19 Post-Infectious Encephalitis Presenting With Delirium as an Initial Manifestation.

We report the case of a 65-year-old man with COVID-19 (coronavirus disease-2019) post-infectious encephalitis who presented with delirium as an initial manifestation. He had severe COVID-19 pneumonia and recovered with dexamethasone and tocilizumab. One week after discharge, he developed abnormal behavior and delirium without fever and respiratory symptoms. Brain magnetic resonance imaging showed no abnormalities. Cerebrospinal fluid showed pleocytosis and elevated protein concentrations and was negative for severe acute respiratory syndrome-coronavirus-2 RNA. No anti-neuronal autoantibodies against intracellular and neuronal surface proteins were detected. The cerebrospinal fluid inflammatory changes compatible with post-infectious encephalitis, and the patient recovered with intravenous methylprednisolone and intravenous immunoglobulin therapy. Delirium could be an initial symptom of post-infectious encephalitis in older adults with COVID-19, and these patients may require immunosuppressive therapy.