The new england JOURNAL of MEDICINE ESTABLISHED IN 181 MARCH 12,2009 V0L.360N0.1 Melamine-Contaminated Powdered Formula and Urolithiasis in Young Children Na Guan,M.D.,Ph.D.Qingfeng Fan,M.D.Ph.D..Jie Ding.M.D.,Ph.D.,Yiming Zhao,Ph.D.,Jingqiao Lu,Ph.D. MD2M.品8MoD ABSTRACT BACKGROUND A recent epidemic of melamine contamination of baby formula in China has been associated with the development of urinary tract stones,though the clinical mani- festations and predisposing factors are incompletely delineated. L..YY and the Re Third d(Y nisterodaquestionnaireothe sts to D No 1XiA or at performed urinalysis. renal-fung on and liver-function tests.urinary tests for biochemical markers and the calcium:creatinine ratio,and ultrasonography.Pow- dered-milk infant formulas were classified as having a high melamine content (>500 ppm),a moderate melamine content (<150 ppm),or no melamine (0 ppm);no formulas contained between 150 and 500 ppm of melamine 2069 RESULTS N Engl] 2009:360 067 Contaminated formula was ingested by 421 of 589 children.Fifty had urinary stone including 8 who had not received melamine-contaminated formula;112 were sus pected to have stones;and 427 had no stones.Among children with stones.5.9% had hematuria and2%had leukocyturia,percentages that did not differ signifi cantly from thoseamong children who were suspected to have stoneso those wh not have ston d (98%)who had s Four o nd in e measured had evidence of ab ne had tubula dysfunctio Children exposed to high-melamine formula were 7.0 times as likely to have stones as those exposed to no-melamine formula.Preterm infants were 4.5 times as likely to have stones as term infants CONCLUSIONS and N ENGLJ MED 360,11 NEJM.ORG MARCH 12,2009 106 The New England Joual of Medicine n engl j med 360;11 nejm.org march 12, 2009 1067 The new england journal of medicine established in 1812 march 12, 2009 vol. 360 no. 11 Melamine-Contaminated Powdered Formula and Urolithiasis in Young Children Na Guan, M.D., Ph.D., Qingfeng Fan, M.D., Ph.D., Jie Ding, M.D., Ph.D., Yiming Zhao, Ph.D., Jingqiao Lu, Ph.D., Yi Ai, M.D., Guobin Xu, M.S., Sainan Zhu, M.S., Chen Yao, M.D., Lina Jiang, M.D., Jing Miao, M.D., Han Zhang, M.D., Dan Zhao, M.D., Xiaoyu Liu, M.D., and Yong Yao, M.D. Abstract From Peking University First Hospital (N.G., Q.F., J.D., Y.A., G.X., S.Z., C.Y., L.J., J.M., H.Z., D.Z., X.L., Y.Y.) and the Re￾search Center of Clinical Epidemiology, Peking University Third Hospital (Y.Z., J.L.) — both in Beijing. Address reprint requests to Dr. Ding at Peking University First Hospital, No. 1, Xi An Men Da Jie, Bei￾jing, 100034, China, or at djnc_5855@126. com. Drs. Guan and Fan contributed equally to this article. This article (10.1056/NEJMoa0809550) was published at NEJM.org on February 4, 2009. N Engl J Med 2009;360:1067-74. Copyright © 2009 Massachusetts Medical Society. Background A recent epidemic of melamine contamination of baby formula in China has been associated with the development of urinary tract stones, though the clinical mani￾festations and predisposing factors are incompletely delineated. Methods We administered a questionnaire to the parents of children 36 months of age or younger who were being screened for a history of exposure to melamine and symp￾toms of, and possible predisposing factors for, urinary tract stones. In addition, we performed urinalysis, renal-function and liver-function tests, urinary tests for biochemical markers and the calcium:creatinine ratio, and ultrasonography. Pow￾dered-milk infant formulas were classified as having a high melamine content (>500 ppm), a moderate melamine content (<150 ppm), or no melamine (0 ppm); no formulas contained between 150 and 500 ppm of melamine. Results Contaminated formula was ingested by 421 of 589 children. Fifty had urinary stones, including 8 who had not received melamine-contaminated formula; 112 were sus￾pected to have stones; and 427 had no stones. Among children with stones, 5.9% had hematuria and 2.9% had leukocyturia, percentages that did not differ signifi￾cantly from those among children who were suspected to have stones or those who did not have stones. Serum creatinine, urea nitrogen, and alanine aminotransferase levels were normal in the 22 children with stones who were tested. Four of the 41 children (9.8%) who had stones and in whom urinary markers of glomerular func￾tion were measured had evidence of abnormalities; none had tubular dysfunction. Children exposed to high-melamine formula were 7.0 times as likely to have stones as those exposed to no-melamine formula. Preterm infants were 4.5 times as likely to have stones as term infants. Conclusions Prematurity and exposure to melamine-contaminated formula were associated with urinary stones. Affected children lacked typical signs and symptoms of urolithiasis. The New England Journal of Medicine Downloaded from nejm.org on October 18, 2011. For personal use only. No other uses without permission. Copyright © 2009 Massachusetts Medical Society. All rights reserved