A novel etiologic factor of highly elevated cholestanol levels: progressive familial intrahepatic cholestasis.

Background Progressive familial intrahepatic cholestasis type 3 (PFIC3) is an uncommon cholestatic liver disease caused by mutations in the ATP binding cassette subfamily B member 4 (ABCB4) gene. Although PFIC3 is frequently identified in childhood, ABCB4 disease-causing alleles have been described in adults affected by intrahepatic cholestasis of pregnancy, hormone-induced cholestasis, low-phospholipid-associated cholelithiasis syndrome or juvenile cholelithiasis, cholangiocarcinoma and in sporadic forms of primary biliary cirrhosis. Cholestanol is a biomarker which is elevated especially in cerebrotendinous xanthomatosis and rarely in primary biliary cirrhosis (PBC) and Niemann Pick type C. Case presentation Here we report a Turkish patient with compound heterozygous mutations in the ABCB4 gene, who has hepatosplenomegaly, low level of high-density lipoprotein, cholestasis and high level of cholestanol. Conclusion This is the first PFIC3 case with a high cholestanol level described in the literature. There are very few diseases linked to increased cholestanol levels, two of which are CTX and PBC. From this case, we can conclude that a high cholestanol level might be another indicator of PFIC type 3.