Neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) is an autosomal recessive metabolic disorder characterized by poor growth, intrahepatic cholestasis, and increased serum citrulline. Most patients show spontaneous improvement by 1 year of age. However, some patients may have a progressive course with continued failure to thrive and dyslipidemia caused by citrin deficiency (FTTDCD), and some may develop chronic or fatal liver disease. [From OMIM]