ABSTRACT
The nephrotic syndrome occurs when heavy proteinuria results in hypoproteinaemia and oedema. It is an uncommon condition with 2-4 new cases per 100 000 children per year. The peak age is 2-6 years and boys are more commonly affected than girls (2.5:1). In most cases (>90%) the cause is unknown (idiopathic or minimal change nephrotic syndrome) and the proteinuria is steroid responsive. There is thought to be an immunological basis and there is an association with atopy. The prognosis is good with <10% progressing to chronic renal failure. Genetic predisposition is associated with HLA-DRW7 and DR3 (six times increased risk) and there is an increased risk in siblings of an affected child. Less commonly the nephrotic syndrome occurs secondary to another disorder and is not steroid responsive. In these children the prognosis is generally poor, more than 30% progressing to renal failure.
