title: Biochemical Screening for Pulmonary Hypertension in Preterm Infants with Bronchopulmonary Dysplasia.
abstract: BACKGROUND
  Pulmonary hypertension (PH) in infants with bronchopulmonary dysplasia (BPD) is associated with increased morbidity and mortality. Elevated levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and decreased levels of amino acid precursors of nitric oxide (NO) have been associated with PH, but have not been studied in infants with PH secondary to BPD.
  
  
  OBJECTIVE
  The aim of this study was to identify a biochemical marker for PH in infants with BPD.
  
  
  METHODS
  Twenty infants, born at <27 weeks' gestational age (GA) and/or with a birth weight (BW) ≤750 g, who met the criteria for BPD at 36 weeks' corrected GA (CGA) were enrolled in this cross-sectional pilot study. A screening echocardiogram was conducted at 36-38 weeks' CGA and plasma NT-proBNP and amino acid levels were obtained within 1 week of the screening echocardiogram.
  
  
  RESULTS
  Five infants (25%) had echocardiographic evidence of PH. GA and BW were not significantly different between the 2 groups (a PH group and a No PH group). NT-proBNP was significantly elevated in the PH group (median 1,650 vs. 520 pg/ml; p = 0.001) but citrulline levels were significantly lower (median 21 vs. 36 μmol/l; p = 0.005). Arginine levels were not significantly different between the groups (median 78 vs. 79 μmol/l; p = 1).
  
  
  CONCLUSIONS
  NT-proBNP and the NO precursor citrulline may be cost-effective biochemical markers for screening for the presence of PH in preterm infants who have BPD. If validated in a larger study, such biochemical markers may, in part, replace PH screening echocardiograms in these patients.
authors.affiliation: Section of Neonatal-Perinatal Medicine, Yale University School of Medicine, New Haven, Conn., USA.
authors.forename: Angela M
authors.initials: AM
authors.lastname: Montgomery
authors.forename: Alia
authors.initials: A
authors.lastname: Bazzy-Asaad
authors.forename: Jeremy D
authors.initials: JD
authors.lastname: Asnes
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Bizzarro
authors.forename: Richard A
authors.initials: RA
authors.lastname: Ehrenkranz
authors.forename: Constance G
authors.initials: CG
authors.lastname: Weismann
mesh_terms: D015415:Biomarkers / Q000097:blood*; D001997:Bronchopulmonary Dysplasia / Q000097:blood* / Q000150:complications / Q000000981:diagnostic imaging; D003430:Cross-Sectional Studies; D004452:Echocardiography; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000097:blood* / Q000000981:diagnostic imaging / Q000503:physiopathology; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood*; D007235:Infant, Premature, Diseases / Q000097:blood* / Q000000981:diagnostic imaging / Q000503:physiopathology; D008297:Male; D015997:Neonatal Screening / Q000379:methods*; D010865:Pilot Projects
chemical_list: D015415:Biomarkers