[1] Univ N Carolina, Dept Med, Div Gastroenterol & Hepatol, Ctr Esophageal Dis & Swallowing, Chapel Hill, NC 27515 USA
[2] Mayo Clin, Div Gastroenterol, Rochester, MN USA
[3] Cincinnati Childrens Hosp Med Ctr, Div Pathol & Lab Med, Cincinnati, OH 45229 USA
[4] Univ Cincinnati, Coll Med, Cincinnati, OH USA
[5] Univ Illinois, Childrens Hosp Illinois, Sect Pediat Gastroenterol Hepatol & Nutr, Peoria, IL USA
[6] Univ Illinois, Coll Med, Peoria, IL 61656 USA
[7] Shire, Lexington, MA USA
[8] Northwestern Univ, Feinberg Sch Med, Div Gastroenterol & Hepatol, Chicago, IL 60611 USA