Prolonged cholestasis following severe neonatal echovirus 11 (genotype D5, new lineage 1) infection diagnosed by serum detection.

Echovirus 11 (E11) genotype D5, new lineage 1, has emerged as a cause of severe and often fatal neonatal infection since 2022. Serum detection of E11 has been associated with particularly poor prognosis, yet post-discharge outcomes of survivors, especially regarding cholestasis, remain poorly described. A term male neonate (38 weeks, 3422 g) developed fever on day of life (DOL) 3 with cerebrospinal fluid positive for enterovirus. By DOL 6, he progressed to disseminated intravascular coagulation and acute liver failure, necessitating pediatric intensive care. E11 (genotype D5, new lineage 1) was identified from serum, cerebrospinal fluid, and stool. He survived with multidisciplinary intensive care including blood product transfusions. Following resolution of the acute phase, conjugated hyperbilirubinemia with cholestasis persisted. Obstructive biliary disease and metabolic disorders were excluded. Cholestasis gradually resolved with ursodeoxycholic acid and fat-soluble vitamin supplementation, and all medications were discontinued by 1 year of age. Prolonged cholestasis may occur during recovery from severe neonatal E11-associated acute liver failure, even after successful acute-phase management. Scheduled post-discharge hepatobiliary monitoring including conjugated bilirubin, along with nutritional interventions, should be incorporated into the follow-up plan for survivors.