Coronavirus HKU1 infection and development of pediatric acute liver failure with immune dysregulation phenotype.

Pediatric acute liver failure is a rare but serious complication of Coronavirus infections. Our patient is a previously healthy 8-year-old male who presented with acute liver failure in the setting of human coronavirus HKU1 (HCoV-HKU1) infection while asymptomatic from a respiratory perspective. During the hospital course, he developed acute hepatic encephalopathy and was listed for liver transplantation, but fortunately recovered remaining status 7 (inactive) on the transplant list. With a negative diagnostic evaluation other than his viral infection and hyperdense CD8 T-cells on liver immunohistochemical staining, pediatric acute liver failure (PALF) immune dysregulation phenotype was diagnosed.