Z Salmón-González1, M Vieitez-Santiago2, M Martino-González3, J L Hernández1, J Alonso-Gutierrez1. 1. Department of Internal Medicine of H.U. Marqués de Valdecilla, Santader, Spain. 2. Department of Internal Medicine of Hospital Laredo, Laredo, Spain. 3. Department of Pathological Anatomy of H.U. Marqués de Valdecilla, Santader, Spain.