Two Chinese children with COVID-19 related acute encephalopathy with restricted diffusion

Acute encephalopathy with biphasic seizure and late restricted diffusion (AESD) is a clinico-radiological syndrome with specific seizure pattern and delayed change in diffusion-weighted magnetic resonance imaging (MRI) of brain. Coronavirus disease 2019 (COVID-19) infection had been reported in association with neurological conditions or complications including AESD. Hereby we described two paediatric cases of definite AESD related to COVID-19 infection. Case-1 was a healthy 17-month-old boy presented with clusters of febrile status epilepticus on Day 1. His conscious state remained impaired despite initial seizure cessation. Seizures recurred on Day 6 and MRI brain showed extensive restricted diffusion over bilateral subcortical and deep white matter. He had significant motor regression and developed dystonia and intractable epilepsy subsequently. Case-2 was a 3-year-old girl with underlying developmental delay admitted for fever, coryza and status epilepticus on Day 2 illness. She improved initially but had seizure recurrence and deterioration in sensorium on Day 6. MRI brain showed restricted diffusion over bilateral fronto-temporo-parietal subcortical white matter with relative sparing over peri-rolandic region. Her function returned to baseline upon recovery. COVID-19 infection-associated AESD was diagnosed in both cases and they had been treated with immunotherapies including tocilizumab during acute disease. Prompt seizure control and early immunotherapies are mainstay of treatment for AESD. Worse outcome was observed in patient with elevated interleukin-6 (IL-6) level in serum and cerebrospinal fluid, longer seizure duration in first-phase and more extensive MRI involvement in second-phase of disease. Early use of IL-6 receptor antibody did not improve the neurological outcome in patient with severe disease.