Mineralogy,geochemistry,and micromorphology of human kidney stones(urolithiasis)from Mersin,the southern Tuirkey

摘要

This study describes the primary char-acteristics of the selected kidney stones surgically removed from the patients at the Mersin University Hospital in the southern Turkey and interprets their formation via petrographic,geochemical,XRD,SEM-EDX,and ICP-MS/OES analyses.The ana-lytical results revealed that the kidney stones are composed of the minerals whewellite,struvite,hydroxyapatite,and uric acid alone or in different combinations.The samples occur in staghorn,bean-shaped composite,and individual rounded parti-cle shapes,which are controlled by the shape of the nucleus and the site of stone formation.The cross-section of the samples shows concentric growth lay-ers due to variations in saturation,characterizing the metastable phase.Kidney stone formation includestwo main stages:(ⅰ)nucleation and(ⅱ)aggrega-tion and/or growth.Nucleation was either Randall plaque of hydroxyapatite in tissue on the surface of the papilla or a coating of whewellite on the plaque,or crystallization as free particles in the urine.Sub-sequently,aggregation or growth occurs by precipita-tion of stone-forming materials around the plaque or coating carried into the urine,or around the nucleus formed in situ in the urine.Urinary supersaturation is the main driving force of crystallization processes;and is controlled by many factors including bacteri-ally induced supersaturation.