The study was aimed to assess the peculiarities of the clinical course and homeostasis in children and teenagers suffering from chronic gastroduodenitis. There was established that the clinical manifestations during disease relapses were stereotypical. The patients have superficial (63.3 %) and erosive (36.7 %) gastroduodenitis. The content of POL metabolites in the saliva of sick children was 1.9–2.2 folds higher than amongst their healthy peers. The secretion of lysocime and sIgA with saliva was less by 15– 20 % than reference levels. The determined patterns of homeostasis require their correction.
