CRYSTAL-OPTICAL CHARACTERISTICS AND FEATURES OF THE MINERAL COMPOSITION OF URINARY TRACT STONES

Abstract

The article provides information about the research were learned the structure and phase composition of urinary tract stones by crystal optical analysis and infrared spectroscopy methods.

The study analyzed the structure and mineral composition of urinary tract stones obtained in 37 patients after extracorporeal shock-wave lithotripsy of kidney and ureter stones. The structure of the calculus was studied on the basis of crystal-optical analysis using a polarizing microscope. The mineral composition of the stone was evaluated by infrared spectroscopy (IRS).

72.9% of the investigated samples of urinary tract stones are represented by the crystalline phase, the main component of which is whewellite, which is present in combination with hydroxylapatite (13.5%), hydroxylapatite and uric acid salts (40.5%), weddellite, carbonate apatite and calcium phosphate (18.9%). In 21.6% of patients, in samples of urinary stones, in addition to the crystalline phase represented by whewellite, an amorphous phase was present in the form of amorphous calcium phosphate (8.1%) and amorphous calcium oxalate (13.5%). In two cases (5.4%), a rare combination of salts was identified: a crystalline phase consisting of uric acid and fluorapatite salts, as well as an amorphous phase in the form of a combination of aragonite and organic acids.

Urinary tract stones have a mixed mineral composition, the prevailing component of which is whewellite. The presence of an amorphous phase in the calculus structure, which is the previous stage in the crystallization process, may indicate a relatively young age of the stone.