NBAS (neuroblastoma-amplified sequence) is a subunit of the NRZ tethering complex involved in Golgi-to-endoplasmic reticulum (ER) retrograde vesicular transport 1. It functions in SNARE assembly at the ER and maintains protein stability within the secretory pathway 2. NBAS is essential for normal vesicular trafficking in high-secretory organs including hepatocytes, bone-forming cells, and immune cells. Biallelic NBAS variants cause recurrent acute liver failure (RALF), typically triggered by febrile infections, representing one of the most frequent genetic causes identified in pediatric liver failure cohorts 3. NBAS deficiency accounts for 7.7% of genetically diagnosed indeterminate pediatric acute liver failure cases 3. Disease manifestations extend beyond isolated hepatic crises to include skeletal abnormalities (osteopenia, dysplasia), short stature, and optic nerve atrophy 2. Recently, NBAS was identified as the second most frequently mutated gene (2.11%) in pediatric hemophagocytic lymphohistiocytosis, where impaired lytic granule polarization in NK cells disrupts cytotoxic degranulation 4. Pathophysiologically, NBAS deficiency impairs retrograde vesicular trafficking, compromising membrane recycling and autophagy, while also impairing antegrade transport causing deficient collagen and insulin secretion 1. This results in increased ER stress leading to hepatocellular death during infections 1. Liver transplantation effectively halts RALF recurrence, though timing remains critical to minimize complications 5.