Regenerative Nodule as a Diagnostic Dilemma in the Neonate With Acute Liver Failure and a Focal Liver Lesion.

Acute liver failure in the neonate generates a broad differential diagnosis of varying etiology including inborn errors of metabolism, infections, cholestatic disorders, gestational alloimmune liver disease (GALD), alpha-1 antitrypsin deficiency, total parenteral nutrition-related injury, malignancy, and others. We present a case of a neonate born at 39 weeks' gestational age who presented on day 5 of life with coxsackievirus (part of the enterovirus family) encephalitis and COVID-19 infection and was subsequently found to be in acute liver failure (INR 1.7 up to 2.8 [not correctable with parenteral vitamin K], ammonia 87 umol/L up to 142 umol/L, AST 1864 IU/L, ALT 535 IU/L) with increasing alpha-fetoprotein. Evaluation for possible liver transplantation included an abdominal MRI, which showed a 2.4 × 1.7 × 2.1 cm round mass-like lesion in segment 2 of the liver, raising a differential diagnosis which included hepatoblastoma. This lesion and the background liver were biopsied. A nonspecific hepatitic pattern of injury was identified within the lesion and the background liver showed nodular post-necrotic changes with collapse of lobular architecture. While clinical case reports exist of acute hepatitis in neonates with COVID-19 alone and coxsackievirus alone, the role dual infection may play in causing severe liver injury is unique to our case and provides territory for continued investigation.