Acute necrotizing encephalopathy of childhood secondary to parainfluenza infection: A review of two cases

Acute necrotizing encephalopathy (ANE) of childhood is a rare inflammatory syndrome, classically associated with preceding febrile illness and followed by fulminant neurological deterioration including encephalopathy, seizures, and focal neurological deficits with multifocal lesions of the thalami, rostral brainstem, and cerebral and cerebellar gray and white matter. ANE is distinctly associated with significant rates of neurological sequelae and death. Multiple infectious and parainfectious etiologies have been associated with ANE, notably influenza A. We report two cases of ANE associated with parainfluenza infection. Both children were treated with high-dose methylprednisolone and intravenous immunoglobulin, and one treated with tocilizumab. However, both patients suffered rapid neurological deterioration and death despite aggressive intervention. We present two cases of ANE with rapid neurological deterioration and death despite aggressive medical therapy. Rapid treatment with immunomodulatory treatments can lead to symptomatic recovery of variable degree in some patients. While high-dose steroids, intravenous immunoglobulin, and plasma exchange are common therapies for ANE, some case reports have suggested interleukin-6 (IL-6) blockade with tocilizumab can be beneficial. We report the nineteenth documented child in pediatric literature treated for ANE with tocilizumab, who did not respond to treatment, suggesting the response is heterogenous and warrants additional investigation.