Hypothalamic pituitary adrenal function in the extremely low birth weight infant

Cheryl E. Hanna, L. Donald Keith, Michael A. Colasurdo, Donald C. Buffkin, Mary R. Laird, Scott H. Mandel, David M. Cook, Stephen H. Lafranchi, John W. Reynolds

Research output: Contribution to journalArticlepeer-review

46 Scopus citations


Extremely premature infants manifest clinical features suggestive of adrenal insufficiency. Yet, serum cortisol levels are similar in ill and well preterm infants in a setting where one would expect high stress levels in the ill infants. We investigated the hypothalamic-pituitary-adrenal axis in 17 extremely low birth weight stressed premature infants, mean birth weight 739 g, gestational age, 26.1 weeks, using ovine CRH (oCRH) and ACTH stimulation. oCRH (1 ¼g/kg) was administered at 2–7 days of life (mean = 4.1). ACTH rose from a basal value 6.0 ± 0.8 pmol/L (mean ± SEM) to 9.6 ± 1.8 pmol/L (P < 0.01) at 15 min and 9.5 ± 1.7 pmol/L (P < 0.01) at 60 min. Basal cortisol rose from 349.3 ± 58.1 nmol/L to 422.3 ± 57.9 nmol/L (P < 0.01) at 15 min and 568.7 ± 60.2 nmol/L (P < 0.01) at 60 min. Cortisol values remained significantly (P < 0.05) elevated 24 h after oCRH. An ACTH stimulation test performed 24 h after the oCRH test demonstrated a significant cortisol rise from 603.5 ± 130.5 nmol/L to 882.7 ± 136.6 nmol/L (P < 0.05) at 60 min. Plasma CRH immunoactivity was also measured before oCRH testing and was detectable in 10 of 15 infants. The mean CRH immunoactivity was 21.8 ± 4.4 pmol/L in the infants, significantly higher than 8 adult male controls (P < 0.04). Our results show a normal pituitary response to ovine CRH and a normal adrenal response to ACTH. We hypothesize that cortisol levels are inappropriately low in some ill preterm infants because of the inability of the extremely premature brain to recognize the stress of the illness or because of inadequate hypothalamic secretion of CRH. The significance of the measurable plasma CRH in the first week of life is unknown.

Original languageEnglish (US)
Pages (from-to)384-387
Number of pages4
JournalJournal of Clinical Endocrinology and Metabolism
Issue number2
StatePublished - Feb 1993

ASJC Scopus subject areas

  • Endocrinology, Diabetes and Metabolism
  • Biochemistry
  • Endocrinology
  • Clinical Biochemistry
  • Biochemistry, medical


Dive into the research topics of 'Hypothalamic pituitary adrenal function in the extremely low birth weight infant'. Together they form a unique fingerprint.

Cite this