How is nephrotic syndrome diagnosed?
The diagnosis is made in a patient with edema and massive proteinuria; that is, a urine protein:creatinine ratio greater than 2 (mg:mg) in a first morning sample in children or >3.5 g/24 hours in adults.
Quantitation of urine protein excretion is mandatory to confirm the diagnosis of new-onset nephrotic syndrome. However, subsequent monitoring can be accomplished using qualitative dipstick urine testing.
It is important to exclude cirrhosis, congestive heart failure, or gastrointestinal disease (protein-losing enteropathy or malabsorption) before conclusively attributing edema to kidney disease.
