[1] Clin & Hosp Ctr Bezanijska Kosa, Dept Gastroenterohepatol, Belgrade 11080, Serbia
[2] Sch Med, Belgrade, Serbia
[3] Clin & Hosp Ctr Bezanijska Kosa, Dept Gastrointestinal Surg, Belgrade 11080, Serbia
[4] Clin & Hosp Ctr Bezanijska Kosa, Dept Hematol, Belgrade 11080, Serbia
[5] Clin Ctr Serbia, Inst Digest Dis, Belgrade, Serbia
[6] Inst Med Stat, Belgrade, Serbia
[7] Inst Anat Niko Miljanic, Belgrade, Serbia