Changes in urinary nanocrystallites in calcium oxalate stone formers before and after potassium citrate intake

nges in urinary nanocrystallites in calcium oxalate stone formers before and after potassium citrate intake Original Research (469) Total Article Views Authors: Duan CY, Xia ZY, Zhang GN, Gui BS, Xue JF, Ouyang JM Published Date March 2013 Volume 2013:8 Pages 909 - 918 DOI: http://dx.doi.org/10.2147/IJN.S39642 Received: 28 October 2012 Accepted: 01 January 2013 Published: 01 March 2013 Chao-Yang Duan,1 Zhi-Yue Xia,2 Guang-Na Zhang,2 Bao-Song Gui,1 Jun-Fa Xue,2 Jian-Ming Ouyang2 1Department of Nephrology, the Second Hospital of Xi'an Jiaotong University, Xi'an, People's Republic of China; 2Institute of Biomineralization and Lithiasis Research, Jinan University, Guangzhou, People's Republic of China Abstract: The property changes of urinary nanocrystallites in 13 patients with calcium oxalate (CaOx) stones were studied before and after ingestion of potassium citrate (K3cit), a therapeutic drug for stones. The analytical techniques included nanoparticle size analysis, transmission electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. The studied properties included the components, morphologies, zeta potentials, particle size distributions, light intensity autocorrelation curves, and polydispersity indices (PDIs) of the nanocrystallites. The main components of the urinary nanocrystallites before K3cit intake included uric acid, β-calcium phosphate, and calcium oxalate monohydrate. After K3cit intake, the quantities, species, and percentages of aggregated crystals decreased, whereas the percentages of monosodium urate and calcium oxalate dehydrate increased, and some crystallites became blunt. Moreover, the urinary pH increased from 5.96 ± 0.43 to 6.46 ± 0.50, the crystallite size decreased from 524 ± 320 nm to 354 ± 173 nm, and the zeta potential decreased from 4.85 ± 2.87 mV to 8.77 ± 3.03 mV. The autocorrelation curves became smooth, the decay time decreased from 11.4 ± 3.2 ms to 4.3 ± 1.7 ms, and the PDI decreased from 0.67 ± 0.14 to 0.53 ± 0.19. These changes helped inhibit CaOx calculus formation.