Physicochemical mechanisms of stone formation

Abstract

In this article, the term "physicochemical mechanism" is defined as a sequential series of steps culminating in the formation of a renal stone. Distinctions are drawn between physicochemical prerequisites for urinary supersaturation, crystallization, and stone formation. In particular, attention is focussed on the transition from crystal to stone. Emphasis is laid on crystal retention being the fundamental mechanism by which stones are formed, and mention is made of the different ways in which it can be achieved. The processes which dictate crystal-size enlargement, either during free particle flow or during fixed particle entrapment, are described. Modulators of these processes are classified in terms of their mode of action on particular steps in the mechanism rather than on their molecular weight or size. Three different approaches for describing stone formation mechanisms are summarized. These involve mathematical models, qualitative step-by-step pathways, and qualitative non-schematic descriptions. It is suggested that although physicochemical mechanisms are crucially involved in stone formation, they do so in concert with numerous other mechanistic processes, all of which are dictated by their own specific conditions.

Proteomics of Crystal–Cell Interactions: A Model for Kidney Stone Research

“…Crystallization can occur either inside renal tubules (intratubular model) or at the renal interstitium (Randall’s plaque model) [4,5,6]. After the crystals are formed, individual crystals become the larger particles by either crystal growth or aggregation mechanism [7,8]. In addition, crystal–cell adhesion causes crystal retention inside the renal tubules or interstitium [9,10].…”

Effectiveness of Herbal Medicine in Renal Lithiasis: a Review

“…The formation of this complex depends on numerous physicochemical factors such as the concentration of individual (competing) chemical species, the relative magnitude of the formation constants of the complexes themselves, the pH and ionic strength of the urine in which the process occurs. 11 As a result of supersaturation, solutes precipitate in urine leads to nucleation and then crystal concretions are formed. 9 The first step in the formation of kidney stone begins by the formation of nucleus (termed as nidus), normally of apatite (calcium phosphate) due to that the heterogeneous nucleation is easier than homogeneous nucleation in physiological conditions of the urine.…”

Prevention of Calcium Nephrolithiasis: The Influence of Diuresis on Calcium Oxalate Crystallization in Urine

“…However, the question of how during phases of urinary supersaturation stones develop on kidney calcifications and how this process can be prevented is not answered definitively [21]. To get more information we studied the physiochemistry of crystallization [22] and performed crystallization experiments on urine of stone formers (SF) and healthy controls (HC).…”