The Mineralogy and Chemistry of Urinary Stones from the United Arab Emirates

Abstract

The purpose of this study is to characterize urinary stones from the United Arab Emirates using mineralogical techniques and compare it with stones in nature. Twenty six urinary calculi were subjected to chemical analysis, XRD, DTA, TGA and polarizing microscopy. The results show that the calculi belong to one of the four groups; namely phosphate (struvite, dehrenite, podolite, and ammonium calcium phosphate hydrate) making 11.5 % of the stones. Oxalate (whewellite and minor weddellite) 38.5%, urates (uricite) 11.5 %, and mixed type 38.5 %. Common mineralogical methods like the use of polarizing microscopy and thermal analysis proved to be a sensitive tool in the investigation of urinary calculi and gave more information than chemical analysis. The role of dietary factors and climate are discussed in relation to renal stones in the United Arab Emirates.