Trace element signatures and regional differences in kidney stones: insights from a high-prevalence region

The global rise in urolithiasis poses significant health risks. However, the formation mechanisms and environmental influences of kidney stones remain poorly understood. Investigating the elemental composition of kidney stones provides a critical approach to exploring these factors. This study analyzed kidney stones from Yunnan Province, a region with high nephrolithiasis prevalence, classifying them into three types: calcium oxalate (CO), uric acid (UA), and mixed CO and carbonate apatite (CA) stones. The long-term accumulation of calcium salts results in significantly higher concentrations of Ca, Zn, and Se in calcium stones compared to the crustal average. The concentrations of most elements in UA stones are generally lower than those in calcium stones. Mg, Zn, and Sr show significant correlations with multiple elements and inhibit stone crystallization, whereas Cu and Se appear to act only in apatite-containing stones. Additionally, the heavy metal characteristics of kidney stones exhibit notable regional differences. Kidney stones from Yunnan show significantly lower Zn and Sr levels than those from other regions, displaying unique geochemical features influenced by regional environmental and dietary factors. The heavy metal characteristics of kidney stones in Yunnan elucidate the mechanistic roles of individual elements and their associated environmental influences.