PREVALENCE OF URINARY STONE TYPES IN CHILDREN AND ADOLESCENTS IN RUSSIA

The incidence of urolithiasis among children is rapidly increasing worldwide. Children with nephrolithiasis are at high risk of developing kidney stone recurrence. The prevalence of various types of urinary stones can vary significantly in different regions of the world. The knowledge of the composition of urinary stones is the most important stage in the examination of a patient with urolithiasis to assess changes in metabolism and prescribe effective metaphylactic treatment. The purpose of the study was to assess the prevalence of urinary stone types in Russia among children and adolescents under 25 years old. Research materials and methods: data on the composition of the urinary stones are presented by “INVITRO,” LLC in anonymized form for the period 2018 to 2021. All urinary stone analyzes were performed in different Russia regions using infrared spectroscopy and/or X-ray diffraction. Results: the prevalence of one-, two-, three- and more multicomponent urinary stones among the Russian children's population was assessed. The research studied the chemical composition of 538 urinary stones, of which single-component composition was found in only 28 cases (5.2%), two-component stones - in 298 studies (55.4%), and three- or more-component stones - in 212 (39.4 %) cases. Single-component calcium-containing stones were detected in 50% of girls and 80% of boys (p<0.001). They are predominantly represented by calcium oxalate monohydrate (COM) both among girls and boys. Attention is drawn to the high frequency of detection of infectious stones from struvite and ammonium urate in girls (100%). Among the two-component stones, the most common stones were those from COM + COD (n=187), which were detected in approximately equal proportions among boys and girls. Stones from COM + struvite and carbonate apatite + struvite were statistically significantly more common in girls (p<0.001). The most common multicomponent stone is a mixture of COM + COD and carbonate apatite (88.2%, n=187), almost evenly distributed among boys and girls. The second most common were stones from a mixture of COM + COD and struvite, statistically significantly more common in girls - 61.9% versus 38.1% in boys (p<0.001). Conclusion: the urinary stone composition analysis has a significant role in the assessment of metabolic disorders and determination of the mechanism of initiation of stone formation. In accordance with the clinical guidelines of the Russian Society of Urology for urolithiasis, approved by the Russian Healthcare Ministry, the study of urinary stones is mandatory. It is necessary to increase the volume of studies of urinary stone composition in children from all the Russia regions.