Urinary Tract Stone Disease in the United States Veteran Population. II. Geographical Analysis of Variations in Composition

Abstract

The geographical distribution of crystalline components observed in urinary tract stones in the continental United States has been studied in the United States veteran population. Since the veteran population is at risk for urolithiasis the National Veterans Administration Crystal Identification Center was established in 1983 for the characterization of all crystal-containing veteran patient samples using high resolution x-ray powder diffraction. The geographical distribution of whewellite, weddelite, apatite, brushite, struvite, uric acid and uric acid dihydrate is presented. The percentage occurrence of the crystalline components, percentage occurrence of admixed stones and geographical distribution of the number of components in admixed stones also are presented. The data highlight that although the southeastern United States has the highest patient discharge rate for stones, this high discharge rate appears to be correlated specifically with a high discharge rate for calcium oxalate stones and not with a high discharge rate for any of the other common stone components.

Modulation of Calcium Oxalate Dihydrate Growth by Selective Crystal-face Binding of Phosphorylated Osteopontin and Polyaspartate Peptide Showing Occlusion by Sectoral (Compositional) Zoning

“…Two polymorphs of calcium oxalate, calcium oxalate monohydrate (COM) 3 and calcium oxalate dihydrate (COD), are the most abundant mineral types, but others may exist in smaller amounts, including calcium phosphate minerals. It has been reported that the occurrence of COM, the more thermodynamically stable polymorph of calcium oxalate, is often at the core of most kidney stones and is approximately twice as frequent as COD (2), although both crystal types typically exist to some degree in most stones (3,4). COM is commonly found in the urine of "stone formers," but seldom is seen in healthy urine; on the other hand, COD crystals are typically found in the urine of both healthy people and stone formers and are routinely excreted during urination (5)(6)(7).…”

Mechanism of Formation of Human Calcium Oxalate Renal Stones on Randall's Plaque

“…The plaque crystal is apatite surrounded by organic materials, one of which is osteopontin . The overgrowth, the stone, is CaOx, but small amounts of calcium phosphate, usually apatite, are very commonly found admixed within it (Mandel and Mandel, 1989). As in plaque, CaOx stone crystals are embedded in an organic matrix (Stapleton et al, 1993;Atmani et al, 1998).…”

Intracrystalline urinary proteins facilitate degradation and dissolution of calcium oxalate crystals in cultured renal cells

“…30 and 38). Those studies showed that COM crystals, which are the predominant form of CaOx occurring in human kidney stones (41), are highly membranolytic (55), and also that their adherence to renal epithelial cells is very rapid, concentration dependent, and significantly greater than crystals of other calcium minerals (33, 36 -37). COM crystals were also shown to adhere to anionic sites on the surface of renal epithelial cells (32), while their attachment was altered by manipulating either cell surface characteristics and/or concentrations of soluble proteins and anions in the culture medium (31)(32)(33)54).…”