Summary
The inhibitory activity of urine on calcium oxalate crystallization was measured as an inhibitory index using a gel model modified from Schneider et al. [8]. Urine samples from 36 recurrent stone formers and 21 controls in 3 separate periods (morning, afternoon and evening) were tested. Mean inhibitory indices of >0 were observed among normal controls in the 3 sampled periods and among stone formers in the morning and afternoon samples. A significantly lower (negative) value was observed in the evening samples of stone formers, indicating a higher tendency towards crystallization than normal. The gel method may be applied to identify individuals at risk of stone formation if sufficient numbers of period-defined urine samples from the individual are tested for a statistically significant mean inhibitory index but whether this is practical in a clinical laboratory will need further evaluations.
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Li, M.K., Shum, D.K.Y. & Choi, S. Detection of crystallization inhibitory activity of whole urine with a gel model. Urol. Res. 15, 75–77 (1987). https://doi.org/10.1007/BF00260936
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DOI: https://doi.org/10.1007/BF00260936