[1] Texas Tech Univ, Dept Internal Med, Hlth Sci Ctr, El Paso, TX USA
[2] Baylor Coll Med, Abdominal Transplant & Liver Dis Clin, Houston, TX 77030 USA
[3] Texas Tech Univ, Div Gastroenterol, Hlth Sci Ctr, El Paso, TX 79901 USA
[4] Texas Tech Univ, Dept Pathol, Hlth Sci Ctr, El Paso, TX USA