Normal pediatric urine contains only trace amounts of protein, usually ≤100 mg/(m2-24h), and is qualitatively negative. A urine protein/urine creatinine ratio ≤0.2 is normal. A positive qualitative test is abnormal if the urine protein level is >150mg/d or >4mg/(m2-h) or >100mg/L. Urine protein is mainly from plasma protein, 2/3 is albumin and 1/3 is Tamm-Horsfall protein and globulin. In nephrotic syndrome, a large amount of proteinuria can occur, with urine protein usually at 3-4 +, within 1 week, and 24h urine protein quantification ≥50mg/kg on 3 occasions.