[1] Virginia Mason Med Ctr, Digest Dis Inst, Seattle, WA 98101 USA
[2] Kansas City VA Med Ctr, Dept Gastroenterol & Hepatol, Kansas City, MO USA
[3] Univ Kansas, Med Ctr, Kansas City, KS 66103 USA
[4] Mayo Clin, Gastroenterol & Hepatol, Rochester, MN USA
[5] Univ Nevada, Las Vegas, NV 89154 USA