Crystallization and other studies
Crystallization is a prerequisite for forming a urinary stone. Whether abnormalities in the process or location of crystallization are the cause of stone formation is less clear. A kidney that performs its task to conserve water will form supersaturated fluid, urine. This occurs in each person. The supersaturation provides the driving force for crystal formation. After sufficient time crystals will form. From there on things are less obvious. If crystals are found in urine, were they formed in the bottle after collection, in the bladder after collection, in the pyelum, or in the nephrons? Is stone formation related to crystal formation per se, to massive crystal formation, or to crystal formation in the wrong place? What is a normal or wrong place - the nephron, the renal tissue, the pelvic space, free in fluid, or fixed to a surface? For all these questions, answering them involves assessing how crystallization proceeds under the specific conditions that exist at a specific site. The aim of this chapter is to describe these conditions, to review literature data in the light of what they tell us about the likelihood and regulation of crystallization at these sites, and to give leads for promising further studies on crystallization in the field of urinary stone formation.