The Formation of Urinary Calculi

Abstract

Normal urine is always grossly super-saturated in regard to the stone-forming salts, which are kept in solution by the action of the colloids. This action is best explained by the theory of adsorption. The amount of the stone-forming salts which can be held in solution depends on the surface area of the colloid, and therefore on its state of subdivision. Precipitation of these salts is due to failure of the colloid to hold them in solution. It may be due to an insufficient quantity, but is more probably due to coagulation of the colloid. When precipitation occurs in the urinary passages, the crystals are usually retained in the lower calyx of the kidney. A crystalline deposit tends to grow into crystalline concretions under the action of surface energy, thus forming true primary calculi. Stones of this type soon irritate the wall of the cavity in which they are contained and cause a reactionary exudate. The laminated stone is formed by continued deposition of crystals, coupled with rhythmic precipitation of a foreign colloid derived from the exudate. Stones originating in infected media are formed in a similar manner.

Synthesis of calcium oxalate crystals in culture medium irradiated with non-equilibrium atmospheric-pressure plasma

“…rinary stone-forming salts can be maintained in solution to the point of supersaturation; the precipitation of these salts is due to the failure of colloids to hold them in solution. 1) Urine is a bio-liquid containing various organic and inorganic waste metabolites that are filtered from the blood by the kidneys. The flow of urine can be impeded by urolithiasis, which is a disease where calculus forms in the urinary tract from the kidney to the urethra.…”

“…4) In general, it is not possible to synthesize artificial urine by mixing urinary crystalloids in the proportions in which they are normally found. 1) The supersaturation of urine is believed to be essential for stone formation; however, the etiology of stone formation remains unclear. 5) Recent technological advances have paved the way for a variety of extraordinary applications of non-equilibrium (cold) atmospheric-pressure plasma (NEAPP).…”