Melamine Crystallization: Physicochemical Properties, Interactions With Other Lithogenic Salts and Response to Therapeutic Agents

No AccessJournal of UrologyInvestigative Urology1 Apr 2012Melamine Crystallization: Physicochemical Properties, Interactions With Other Lithogenic Salts and Response to Therapeutic Agents Ngork-Wah Poon, Mayur Danny I. Gohel, Clara Lau, Ellis Kam-Lun Hon, Ping-Chung Leung, and Chi-Fai Ng Ngork-Wah PoonNgork-Wah Poon Department of Health Technology and Informatics, Hong Kong Polytechnic University, Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China , Mayur Danny I. GohelMayur Danny I. Gohel Department of Health Technology and Informatics, Hong Kong Polytechnic University, Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China , Clara LauClara Lau Institute of Chinese Medicine, Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China , Ellis Kam-Lun HonEllis Kam-Lun Hon Department of Paediatrics, Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China , Ping-Chung LeungPing-Chung Leung Institute of Chinese Medicine, Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China , and Chi-Fai NgChi-Fai Ng Department of Surgery, Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China View All Author Informationhttps://doi.org/10.1016/j.juro.2011.11.078AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: There were reports of children in the People's Republic of China being hospitalized with renal stones and/or failure by September 2008, which were caused by melamine and its co-contaminant cyanurate. We investigated the physicochemical behavior of melamine, its interaction with other endogenous urine factors and the response to therapeutic agents in the renal environment in vitro. Materials and Methods: A mixed suspension, mixed product removal system was set up for crystallization studies of melamine in urine. Crystallization kinetic parameters, including the nucleation and growth rates, and suspension density, were determined according to crystal number and size, as measured by a Coulter particle counter. Results: Melamine crystallized out from urine under normal urinary conditions (pH 5.0 to 6.5) but crystallization was strongly inhibited at pH 4.5 or lower. Melamine significantly enhanced calcium oxalate precipitation while uric acid significantly decreased melamine crystallization. Bacteria mimicking urinary tract infection promoted melamine crystallization. Clinical relevant drugs, such as citrate and bicarbonate, significantly decreased melamine crystallization. Conclusions: This implies that melamine crystallizes under normal urinary conditions and can interact with other lithogenic salts and pose a significant risk for other stones. Urinary tract infection promotes melamine crystallization. Citrate and bicarbonate therapy are effective prophylactic agents against melamine induced crystallization. References 1 : Outbreaks of renal failure associated with melamine and cyanuric acid in dogs and cats in 2004 and 2007. J Vet Diagn Invest2007; 19: 525. Google Scholar 2 : Assessment of melamine and cyanuric acid toxicity in cats. J Vet Diagn Invest2007; 19: 616. Google Scholar 3 : Chinese dairy exports decline. Shanghai: BBC NewsDecember 2, 2008. http://news.bbc.co.uk/2/hi/asiapacific/7759920.stm. Accessed January 20, 2011. Google Scholar 4 : : Centre for Health Protection, Department of Health, Government of the Hong Kong Special Administrative RegionMarch 25, 2009. http://www.chp.gov.hk/en/view_content/13990.html. Accessed January 20, 2011. 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Link, Google Scholar © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4April 2012Page: 1483-1490 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.KeywordskidneycalculimelaminecrystallizationPeople's Republic of ChinaMetrics Author Information Ngork-Wah Poon Department of Health Technology and Informatics, Hong Kong Polytechnic University, Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China More articles by this author Mayur Danny I. Gohel Department of Health Technology and Informatics, Hong Kong Polytechnic University, Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China More articles by this author Clara Lau Institute of Chinese Medicine, Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China More articles by this author Ellis Kam-Lun Hon Department of Paediatrics, Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China More articles by this author Ping-Chung Leung Institute of Chinese Medicine, Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China More articles by this author Chi-Fai Ng Department of Surgery, Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China More articles by this author Expand All Advertisement PDF downloadLoading ...