Ultrasound of urinary system and urinary screening in 14 256 asymptomatic children in China.
OBJECTIVE
The aim of this study is to assess the characteristics of urinary system diseases and the role of the ultrasound screening and urinalysis screening for chronic kidney disease (CKD) in asymptomatic children in China.


METHODS
Between September 2008 and November 2008, 14 256 children excluding those with obvious symptoms and signs were enrolled in our study. All the subjects accepted ultrasound and urinary screening. A case-control study was performed to evaluate the relative risk of having stones in those children exposed to melamine formula.


RESULTS
Of the enrolled children, 6.10% (869 of 14 256) showed abnormalities, of which 409 (2.87%) were established by ultrasound, 572 (4.01%) by urinalysis and 112 (0.79%) by both ultrasound screening and urinalysis. The abnormalities included congenital anomalies of kidney and urinary tract, urinary stones and/or hydronephrosis, leucocyturia and haematuria and/or proteinuria. Children exposed to melamine formula were 5.17 times as likely to have kidney stones as children exposed to no-melamine formula (95% confidence interval, 3.28-8.14; P < 0.001); the probability of kidney stones in melamine-fed infants were 6.28 times as likely as those no melamine-fed (95% confidence interval, 3.71-10.65; P < 0.001).


CONCLUSIONS
Ultrasonography and urinalysis could complement each other and play important roles in the early diagnosis of anomalies of the urinary system, but urinalysis is a more cost-effective screening tool for CKD in children in China. Exposure to melamine-contaminated formula associated with urinary stones, especially in infants, was significantly higher than the control group.
Yang
Haiping
H
Department of Nephroimmunology and Children's Hospital of Chongqing Medical University, 136 Second Zhongshan Road, Yuzhong District, Chongqing 400014, China.
Wang
Qiao
Q
Luo
Juan
J
Li
Qiu
Q
Wang
Li
L
Li
Cui-Cui
CC
Zhang
Gaofu
G
Xu
Zhene
Z
Tao
Hong
H
Fan
Zhongxiang
Z
D000293:Adolescent; D044466:Asian People; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D002681:China; D002908:Chronic Disease; D042241:Early Diagnosis; D005260:Female; D005506:Food Contamination; D006417:Hematuria / Q000175:diagnosis / Q000000981:diagnostic imaging; D006801:Humans; D006869:Hydronephrosis / Q000175:diagnosis / Q000000981:diagnostic imaging; D007223:Infant; D041943:Infant Formula; D007231:Infant, Newborn; D007674:Kidney Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000208:ethnology; D008297:Male; D008403:Mass Screening / Q000379:methods*; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011507:Proteinuria / Q000175:diagnosis / Q000000981:diagnostic imaging; D018570:Risk Assessment; D012307:Risk Factors; D014227:Triazines / Q000009:adverse effects; D014463:Ultrasonography; D016482:Urinalysis; D014545:Urinary Calculi / Q000139:chemically induced / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000208:ethnology; D014564:Urogenital Abnormalities / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000208:ethnology
D014227:Triazines; C011907:melamine