Crystals seen in human urinary stones namely whewellite, weddellite, brushite, octocalcium phosphate, apatite, struvite and newberyite were grown in vitro in silica gel medium. The crystal growth medium was reproduced with addition of known inhibitors of crystallisation namely tartaric acid and citric acid and urine samples of stone patients and normal controls. The size and shape of the crystals were studied in the original setup and on addition of various agents as observed under the scanning electron microscope (SEM). The SEM appearance of crystals was uniformly reproducible. Addition of known inhibitors produced alteration of crystal habit and stunting of growth. Urine of stone patients produced changes in crystal appearance. Normal urine samples produced reduction in size of crystals and altered shapes. It is surmised from the observations that normal urine contains inhibitors of crystallisation and these are absent in the urine of certain stone formers.
Fazil Marickar, Y. M. and Koshy, Peter
"Scanning Electron Microscopic Study of Effect of Various Agents on Urinary Crystal Morphology,"
Scanning Microscopy: Vol. 1
, Article 14.
Available at: https://digitalcommons.usu.edu/microscopy/vol1/iss2/14