About 10,000 children called KunQi Cohort are born in Jiangsu Province(8,000 in Kunshan and 2,000 in Qidong) and about 3,000 born in Shanghai. Children will receive urine and ultrasound screening in 0-3 months ,and complete 3 to 6 years of follow-up( at least one type screening every year)

When an infant was born, he/she will receive the first urine and ultrasound screening in 3 months in Kunshan/Qidong City Maternal and Child Health Hospital.In Kunqi Cohort, 9,000 will complete 3 years follow-up(urine screening once every year, another ultrasound screening in 24-30 months). Urine sample (50ml) will be stored only once within one year. Dry blood filter paper(120ul) will be stored once a year when he or she has a blood routine for future study.1,000 children will complete 6 year follow-up(receive urine and ultrasound screening once every year). Urine sample (50ml) will be stored once a year. Dry blood filter paper(120ul) will be stored once a year when he or she has a blood routine for future study. The 14 urine test items include: leukocytes, urobilinogen, microalbumin, protein, bilirubin, glucose, ascorbic acid, specific gravity, ketone bodies, nitrite, creatinine, pH, occult blood, and urinary calcium. Ultrasound test will screen for kidneys, ureters and the bladder.

The number of CKD patients diagnosed according to the routine diagnosis and treatment of the department of nephrology in Children's Hospital of Fudan University in the 3-6 year observation period accounted for the percentage of the total cases studied.

9,000 children's urine samples (50ml) will be stored as biospecimen retention at -80°C only once within one year, another 1,000 children's urine samples (50ml) will be stored also as biospecimen retention at -80°C once a year.

Biospecimen retention will be used to characterize the urinary and metabolome and proteome in children also expect to identify urine biomarkers for the early diagnosis of CKD.