RISK FACTORS FOR RICKETS DEVELOPMENT IN CHILDREN UNDER PRESENT CONDITIONS

The problem of rickets attracted the interest of pediatricians for a long time. From the first descriptions of the disease by Glisson and Whistler scientists were looking for etiological factors and ways of its treatment. In the first part of XX century it was established that hypovitaminosis D played the main role in the pathogenesis of rickets. That finding was followed by the recommendations of regular use of vitamin D in the disease prevention.

Recent studies of vitamin D metabolism established the presence of some factors that can influence the effectiveness of preventive measures. In addition to geographical conditions and the lack of cholecalciferol in breast milk there are special risk factors that can damage its metabolism in child’s organism.

Adverse social and ecological conditions as well as recurrent infectious diseases can be important factors in rickets development in child. Complicated pregnancy, intrauterine growth retardation can lead to late maturing of enzyme systems that can be followed by damaged vitamin D and Ca-P metabolism and rickets formation even in cases of adequate cholecalciferol supplementation. Liver and kidney diseases can also influence adequate formation of active metabolites of vitamin D. Moreover it is well known that infants who gain fast in weight are more predisposed to the disease. All these risk factors can cause endogenous hypovitaminosis D in child’s organism even in cases of its additional supplementation.

The main risk factors were established by A. I. Ryvkin in 1985. Afterwards there were no trials to describe the structure of risk factors according to social-economical changes, women’s health, children’s development and feeding practices. The recent trial with the aim to study the modern clinical and laboratory features of rickets in infants was carried out in 2008–2011 on the pediatric faculty of Russian medical academy of postgraduate education. 179 infants aged from2to 30 months were included into the study. The results demonstrated that endogenous factors such as accelerated growth and weight gain and liver and kidney diseases are the most important risk factors that predispose the child to rickets formation even in cases of additional vitamin D supplementation.