Osmotic Fragility in Red Blood Cells of Pediatric Patients With Cholestatic Liver Disease

Objective: The investigators propose to perform ektacytometry on 20 pediatric patients over age one with cholestatic liver diseases and a direct bilirubin level of greater than 2 gm/dl. The most common diagnoses will be extrahepatic biliary atresia, progressive familial intrahepatic cholestasis, Alagille syndrome, autoimmune hepatitis, primary sclerosing cholangitis, and parenteral nutrition-associated cholestasis. The investigators will correlate the osmotic fragility and deformability with direct bilirubin levels, serum cholesterol levels, serum bile acid levels, and vitamin E levels. Design/Methods: This pilot study will be a single center, prospective cross-sectional investigation of red blood cell ektacytometry in pediatric patients with extrahepatic cholestasis who are followed at Cincinnati Children's Hospital Medical Center. The study will include all participants with cholestasis regardless of the etiology in order to maximize the number of participants. While the population will be heterogeneous, the investigators will stratify participants according to diagnosis, recognizing that only a few participants may fall into each diagnostic category. Ektacytometry will be the method utilized to measure osmotic fragility and deformability of the RBC membrane. The ektacytometry of red cells from cholestatic patients will be compared to that of red cells obtained from contemporaneous age-matched controls recruited among patients without liver disease or red cell membrane defects undergoing blood sampling for evaluation of other entities including but not confined to functional abdominal pain.