Authors contribution
AR Gratacos: Made substantial contributions to the conception, design of the study, and writing of the article
J Meneses: Made substantial contributions in the data acquisition
L Gonzalez: Has performed the histological study of all the biopsies of the study patients
J Joyanes: Realization of the study tables
A Palacios: Search of the bibliography
E Gomez: Supervision, and submission of the manuscript
All the authors have reviewed all the patients during the years of the study.