Urinary NT-proBNP as a potential noninvasive biomarker for screening of pulmonary hypertension in preterm infants: a pilot study

Objective This pilot study aimed to determine the feasibility of urinary NT-proBNP (NT-proBNP) as a potential noninvasive screening marker for pulmonary hypertension (PH). Study design A prospective cross-sectional study was conducted. Preterm infants (PI) (birthweight <1500 gm and <30 weeks gestational age (GA)) were enrolled. Serial urinary NT-proBNP measurements and echocardiograms (ECHO) were performed at 28, 32, and 36 weeks. Results Thirty-six patients were included in the final analysis (BPD-PH group = 6, BPD group = 20, control = 10). Urinary NT-proBNP levels were higher in the BPD-PH group compared with BPD and control groups at all study intervals. A urine NT-proBNP cutoff level of 2345 pg/ml at 28 weeks of GA had a sensitivity and specificity of 83.3% and 84.2%, respectively, for detection of BPD-PH (AUC 0.816, p = 0.022). Conclusion Urinary NT-proBNP measurement is feasible in preterm infants and appears to be a good noninvasive screening tool for PH.