title: Infrared spectroscopic analysis of urinary stones (including stones induced by melamine-contaminated milk powder) in 189 Chinese children.
abstract: OBJECTIVE
  The aim of the study was to investigate the composition of the stones in Chinese children with urolithiasis, including peculiar stones induced by melamine-contaminated milk powder.
  
  
  METHODS
  Between 1999 and 2009, 189 urinary stones from children of East China were received at our institution. Among them, 12 stones were received from pediatric stone formers with a history of consuming melamine-contaminated milk powder in 2008; and the remaining stones were defined as "natural" stones. All stones were analyzed by Fourier transform infrared spectroscopy.
  
  
  RESULTS
  Among 177 "natural" stones, whewellite stone (49.72%) was observed most frequently followed by weddellite stone (15.25%), uric acid anhydrous stone (9.6%), carbapatite stone (9.04%), cystine stone (9.04%), ammonium acid urate stone (4.52%), struvite stone (2.26%), and sodium urate stone (0.56%). Twelve young children who consumed melamine-contaminated milk powder were younger than 3 years, and their stones were composed of a mixture of uric acid dihydrate and ammonium acid urate based on Fourier transform infrared spectroscopy. In addition, the stones were radiolucent and could be dissolved by urine alkalinization.
  
  
  CONCLUSIONS
  Our study emphasizes the relatively high rate of calcium oxalate stones and cystine stones, and the relatively low rate of struvite stones in Chinese children with urolithiasis. The stones caused by melamine-contaminated milk powder are composed of the mixture of uric acid dihydrate and ammonium acid urate.
authors.affiliation: Department of Urology, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Jiangsu Province, Nanjing 210008, People's Republic of China. Electronic address: sunxizhaonj@163.com.
authors.forename: Xizhao
authors.initials: X
authors.lastname: Sun
authors.affiliation: Department of Urology, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Jiangsu Province, Nanjing 210008, People's Republic of China.
authors.forename: Luming
authors.initials: L
authors.lastname: Shen
authors.affiliation: Department of Urology, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Jiangsu Province, Nanjing 210008, People's Republic of China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Cong
authors.affiliation: Department of Urology, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Jiangsu Province, Nanjing 210008, People's Republic of China.
authors.forename: Huaijun
authors.initials: H
authors.lastname: Zhu
authors.affiliation: Department of Urology, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Jiangsu Province, Nanjing 210008, People's Republic of China.
authors.forename: Jianlin
authors.initials: J
authors.lastname: Lv
authors.affiliation: Department of Urology, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Jiangsu Province, Nanjing 210008, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: He
mesh_terms: D000293:Adolescent; D000818:Animals; D002129:Calcium Oxalate / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008892:Milk / Q000009:adverse effects* / Q000737:chemistry; D011208:Powders / Q000009:adverse effects* / Q000032:analysis; D012189:Retrospective Studies; D013055:Spectrophotometry, Infrared / Q000379:methods*; D014227:Triazines / Q000009:adverse effects* / Q000032:analysis; D014545:Urinary Calculi / Q000139:chemically induced / Q000737:chemistry* / Q000453:epidemiology
chemical_list: D011208:Powders; D014227:Triazines; D002129:Calcium Oxalate; C011907:melamine