[1] Johns Hopkins Univ, Sch Med, Div Gastrointestinal & Liver Pathol, Dept Pathol, Baltimore, MD 21205 USA
[2] Johns Hopkins Univ, Sch Med, Dept Internal Med, Div Gastroenterol, Baltimore, MD 21205 USA
[3] Johns Hopkins Univ, Sch Med, Dept Dermatol, Baltimore, MD 21205 USA