Objective    To summarize clinical characteristics of primary nephrotic syndrome (PNS) in children.     Methods    The clinical and laboratory data of 964 children with PNS (including 747 new cases) were retrospectively analyzed

who were admitted between 1 August

1996 to 31 July

2006.     Results    Of 747 cases

568 were males and 179 females

with a median age of 4.7 years (0.3-17.3). The total number of children with PNS aged from 1 to 5 years was 385 (51.5%). Compared with children with nephritic type nephrotic syndrome (NNS)

children with simple type nephrotic syndrome (SNS) had lower albumin (P0.05)

higher cholesterol and lower dens

ity lipoprotein (P0.05)

and no statistical difference in 24-hour urine protein (P0.05); Compared with normal values

children with PNS had lower IgG (P0.01)

higher IgM and IgE (P0.05)

and no statistical difference in C

3

and IgA levels (P0.05). Main motivation of PNS relapse in children was upper respiratory infection

followed by irregular administration of glucocorticoids.     Conclusion    Children aged from 1 to 5 years are susceptible to PNS. There is humoral immunological dysfunction in PNS children. In the treatment of PNS

to relieve hyperlipidemia and to prevent and control infections is the key point. To strengthen propaganda and guidance about PNS is important as well.