title: Reduced activity of 11β-hydroxylase accounts for elevated 17α-hydroxyprogesterone in preterms.
abstract: OBJECTIVE
  To characterize the urinary steroid metabolome of neonates and infants born either at term or preterm.
  
  
  METHODS
  We retrospectively analyzed urinary steroid hormone metabolites determined by gas chromatography-mass spectrometry of 78 neonates and infants born at term and 83 neonates and infants born preterm (median 34 weeks of gestational age). The subjects' 11β-hydroxylase and 21-hydroxylase activities were assessed on the basis of urinary metabolite substrate-to-product ratios.
  
  
  RESULTS
  Preterm neonates and infants had elevated urinary concentrations of 17α-hydroxyprogesterone (17OHP) metabolites (P<.001) but lower urinary concentrations of the 21-deoxycortisol metabolite pregnanetriolone (PTO) (P<.01). One reason was lower 11β-hydroxylase activity in preterms. We could demonstrate a correlation between low 11β-hydroxylase activity and high urinary concentrations of 17OHP metabolites (r=0.51, P<.001) but low urinary concentrations of the 21-deoxycortisol metabolite PTO (r=-0.24, P=.03) in preterms.
  
  
  CONCLUSIONS
  Low 11β-hydroxylase activity may explain increased 17OHP but decreased 21-deoxycortisol metabolite excretion in preterms. Our analysis clarifies, first, why preterms have higher 17OHP levels and thus higher rates of false-positive screening results for congenital adrenal hyperplasia than do term infants, and, second, why 21-deoxycortisol or its urinary metabolite PTO is more specific than 17OHP for the diagnosis of 21-hydroxylase deficiency.
authors.affiliation: Division of Pediatric Endocrinology and Diabetology, Steroid Research and Mass Spectrometry Unit, Center of Child and Adolescent Medicine, Justus Liebig University, Giessen, Germany. Electronic address: Clemens.kamrath@uni-giessen.de.
authors.forename: Clemens
authors.initials: C
authors.lastname: Kamrath
authors.affiliation: Division of Pediatric Endocrinology and Diabetology, Steroid Research and Mass Spectrometry Unit, Center of Child and Adolescent Medicine, Justus Liebig University, Giessen, Germany.
authors.forename: Michaela F
authors.initials: MF
authors.lastname: Hartmann
authors.affiliation: Division of Pediatric Endocrinology and Diabetology, Steroid Research and Mass Spectrometry Unit, Center of Child and Adolescent Medicine, Justus Liebig University, Giessen, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Boettcher
authors.affiliation: Division of Pediatric Endocrinology and Diabetology, Steroid Research and Mass Spectrometry Unit, Center of Child and Adolescent Medicine, Justus Liebig University, Giessen, Germany.
authors.forename: Stefan A
authors.initials: SA
authors.lastname: Wudy
mesh_terms: D019326:17-alpha-Hydroxyprogesterone / Q000652:urine*; D000312:Adrenal Hyperplasia, Congenital / Q000201:enzymology* / Q000652:urine*; D002849:Chromatography, Gas; D003350:Cortodoxone / Q000652:urine; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D013058:Mass Spectrometry; D055442:Metabolome; D011279:Pregnanetriol / Q000031:analogs & derivatives / Q000652:urine; D012189:Retrospective Studies; D013252:Steroid 11-beta-Hydroxylase / Q000097:blood*; D013254:Steroid 17-alpha-Hydroxylase / Q000097:blood
chemical_list: D011279:Pregnanetriol; C009030:pregnanetriolone; C003556:21-deoxycortisol; D019326:17-alpha-Hydroxyprogesterone; D013254:Steroid 17-alpha-Hydroxylase; D013252:Steroid 11-beta-Hydroxylase; D003350:Cortodoxone