Elevated plasma levels of N-terminal pro-brain natriuretic peptide in children with acute poststreptococcal glomerulonephritis.

Acute poststreptococcal glomerulonephritis (APSGN) is the most common prototype of acute glomerulonephritis in children, and is characterized by the sudden onset of gross hematuria, edema, hypertension and volume overload. Brain natriuretic peptide (BNP) is produced in both the brain and the heart. Its prohormone, proBNP, is cleaved to biologically active BNP and an inactive N-terminal peptide of proBNP (NT-proBNP). NT-proBNP is released predominantly from the ventricles in response to hypervolemia and pressure overload. We therefore investigated the relationship between NT-proBNP levels and cardiac functions of patients with APSGN. NT-proBNP levels were measured in 28 patients with APSGN (17 boys and 11 girls of 8.2 +/- 2.9 years old) and in 26 healthy children (control group). Echocardiograms were performed in both patient and control groups on admission, and only in the patient group two weeks later. Upon admission, the plasma NT-proBNP levels were higher in the patients than in the control group (8876.2 +/- 9650.8 vs 69.5 +/- 22.2 pg/mL, p < 0.001), and left ventricular dysfunction was detected in six patients. Moreover, NT-proBNP levels were significantly higher in the patients with left ventricular dysfunction than other patients (n = 22). There was no significant difference in the levels of NT-proBNP between the patient and control groups, after diuretic treatment of the patients. Plasma NT-proBNP levels were positively correlated with the severity of APSGN. Thus, NT-proBNP level may be a useful marker to assess the volume overload and cardiac function in the follow up of selected APSGN patients.