Staghorn stones’ composition analysis features

The lack of standards in the analysis of the chemical composition of the staghorn stones leads to a decrease in the effectiveness of metaphylaxis, and especially in those cases where the volume of the stone is much larger than the volume of the stone fragment being studied. The aim of this study was to develop standards in order to determine the composition of the staghorn calculi. In the Institute of urology from 2015 to 2016, we identified patients with urolithiasis, staghorn-stone nephrolithiasis who were eventually hospitalized. All patients underwent percutaneous nephrolithotripsy, and fragments of the stone were taken in order to analyze its chemical composition. An analysis of the composition of various fragments taken from different zones of the same calculus was made. Patients were divided into 4 groups depending on the composition of the stone. The first group included patients with a predominance of phosphate in the internal layer of the pelvic fragment of the stone, the second group – with a predominance of oxalates, the third – with a predominance of urates, the fourth – with cystine stones. Our experience, while doing stone analysis, showed that the composition did not coincide in 77% of cases, and in 41,6% of cases a new component in the chemical composition of the stone appeared. Complete coincidence of the composition in the cortical and internal layer of the stone was detected in 35% of the cases, and component coincidence in 58% of cases. In the cortical and internal layers of the pelvic fragments, the total and component coincidence of the composition was 38% and 58%, respectively. Thus, we show the importance of chemical analysis of stones and that the composition of the stone may vary, depending on its location. Timely detection of changes in the nature of the stone allows an adequate treatment of urolithiasis.