Cytokine Storm may Play a Role in the Pathogenesis of Human Parechovirus Type 3-Associated Acute Encephalopathy in Neonates: A Case Report

Background: Human parechovirus type 3 (HPeV3) is an important cause of acute encephalitis in the neonatal and early infantile periods. Typical HPeV3-associated acute encephalitis paradoxically shows no cerebrospinal fluid (CSF) pleocytosis despite virus detection in CSF and diffuse deep white matter involvement of the corpus callosum on magnetic resonance images (MRI). Patient: An 8-day-old full-term infant was found to have HPeV3 infection of the central nervous system (CNS), which was confirmed using diffusion-weighted MRI showing poor diffusivity in the bilateral deep white matter and the corpus callosum without CNS pleocytosis, as seen in previously reported cases. Interestingly, this patient had extremely elevated serum ferritin and urinary beta-2-microglobulin levels, which indicated a surge of the cytokines tumor necrotizing factor alpha and interferon gamma. Conclusion: These findings suggest that the cytokine storm can promote the pathogenesis of white matter lesions in HPeV3-associated acute encephalopathy rather than direct infection of the brain.