Iwanaga K, et al. – The physicians attempted to clarify the difference in response to CRH stimulation tests for preterm infants with or without relative adrenal insufficiency (RAI). They provided evidence that base cortisol levels of preterm infants with RAI were not different from those without RAI. However, CRH stimulation tests could be a useful tool for the diagnosis of RAI in preterm infants.

Methods

• The physicians performed CRH stimulation tests for preterm infants born at a gestational age of <30 weeks at around two weeks of age, between June 2009 and December 2015.
• Retrospectively, subjects were classified into two groups: infants with RAI (n=9) or without RAI (n=17) based on the clinical symptoms and responsiveness to hydrocortisone.

Results

• They found no difference in base or peak serum cortisol levels related to CRH stimulation tests between the two groups.
• However, delta cortisol levels and responsive ratio (peak to base ratio) were significantly reduced in infants with RAI.
• 140 nmol/L for delta cortisol or 1.5 times for peak to base ratio might be cut off levels in preterm infants.