We report a 7-year-old girl with 22q13 deletion syndrome, 46,XX,Ish del(22)(q13.3)(ARSA-; D22S1726), who developed a fulminant autoimmune hepatitis requiring orthotopic liver transplantation. Recently, it has been suggested that the Shank3 gene product, whose deficiency is responsible for the features observed in this syndrome, could play a role in immunological response. Despite an increased incidence of respiratory infections, autoimmune diseases have thus far not been reported in patients with this syndrome. This is the first case of fulminant autoimmune hepatitis associated with the 22q13 deletion syndrome. The possible relationships between immune system dysfunctions peculiar of this syndrome and autoimmune hepatitis are discussed.