Background. Nephrotic syndrome (NS) is a common kidney disease in childhood. The disease is characterized by massive proteinuria, hypoalbuminemia and edema. Edema is one of the main characteristics of NS, but its pathogenesis is still not fully understood.
Objective. Assessment of the state of intravascular volume using echocardiography parameters.
Material and methods. The study included 80 children with different types of NS, aged from 2 to 18 years. Intravascular volume status was assessed by determining the inferior vena cava index, inferior vena cava contractility index, left atrium diameter and aortic annulus diameter.
Results. In 28 patients, the mean index of the inferior vena cava contractility was 11.94±7.80%, the mean diameter of the left atrium was 22.09±12.42 mm/m2, the diameter of the aortic ring was 25.34±5.64 mm. In the remaining 52 patients, the mean index of the inferior vena cava contractility was 13.98±5.21%, the mean diameter of the left atrium was 27.78±6.99 mm/m2, the diameter of the aortic ring was 20.23±3.72 mm.
Conclusion. Echocardiographic parameters such as inferior vena cava contractility index, left atrial diameter, and aortic annulus diameter were the best predictors of body fluid volume status in NS and were a useful guide for assessing intravascular volume status in children. This study also showed that a wide range of patients with NS are normovolemic or hypervolemic.

Keywords: intravascular status, echocardiography, nephrotic syndrome