1. Liver Unit and Digestive Department Hospital General Universitario Gregorio Marañón Madrid Spain
2. Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas Instituto de Salud Carlos III Madrid Spain
3. Department of Microbiology Hospital General Universitario Gregorio Marañón Madrid Spain
4. Department of Surgery Hospital General Universitario Gregorio Marañón Madrid Spain
5. School of Medicine Complutense University of Madrid Madrid Spain