Biliary atresia (BA) results in newborn cholestasis, which necessitates hepatoportoenterostomy or liver transplantation (LT) for long-term survival. Sarcopenia and sarcopenic obesity have been linked to poor clinical outcomes, therefore nutritional optimization is essential. At the moment, the mid upper arm circumference (MUAC) is thought to be the most accurate predictor. The study’s goal was to identify computed tomography (CT)-based body metrics in babies with BA and compare them to MUAC. It looked back at all BA babies under the age of two who had CT scans as part of LT screening at our hospital between 2006 and 2019. The following variables were measured and indexed with length: MUAC, total psoas muscle surface area (tPMSA), cross-sectional skeletal muscle area (CSMA), and total abdominal fat area. Pearson coefficients and intraclass correlation coefficients were computed. The CSMA-to-abdominal fat area ratio was split into quartiles, with the lowest quartile group classified as sarcopenic obesity. Eighty babies were enrolled in the study, with a median age of 4.6 months at the time of LT screening. The CSMA-to-abdominal fat area ratio less than 0.93 was used to define sarcopenic obesity.

During LT screening in BA babies, CT-based body metrics may be determined with high interobserver agreement. The lack of association between CT-based body metrics and MUAC implies that CT-based body metrics, such as relative muscle mass, give extra information on body composition in BA babies.