A. I. Khavkin
Research Clinical Institute of Childhood of the Moscow Region; Belgorod National Research University
Russian Federation

Anatoly I. Khavkin — Dr. Sci. (Med.), Professor, Head of the Department of Gastroenterology and Dietetics named after A.V. Mazurin, Head of the Moscow Regional Center of Pediatric Gastroenterology and Hepatology; Professor of the Department of Pediatrics with a Course in Pediatric Surgical Diseases, Medical Institute

115093, Moscow, Bolshaya Serpukhovskaya str., 62

A. V. Nalyotov
Donetsk State Medical University name after M. Gorky
Russian Federation

Andrew V. Nalyotov — Dr. Sci. (Med.), Professor, Head of the Department of Pediatrics No. 2

283003, Donetsk, Illicha avе., 16

N. A. Marchenko
Donetsk State Medical University name after M. Gorky
Russian Federation

Nataliya A. Marchenko — Teaching Assistant of the Department of Pediatrics No. 2

283003, Donetsk, Illicha avе., 16