Relative adrenal insufficiency in the preterm and term infant

Abstract

Cortisol release in the face of illness or stress is vital for survival. Relative adrenal insufficiency occurs when a patient's cortisol response is inadequate for the degree of illness or stress. Numerous studies have documented the existence of relative adrenal insufficiency in critically ill adults, and its association with increased morbidity and mortality. There is increasing evidence that relative adrenal insufficiency may be an etiology for hemodynamic instability and hypotension in the critically ill newborn, but compared with the adult population, there is still a paucity of data in this population. Randomized controlled trials are needed to evaluate the efficacy and safety of glucocorticoids for the treatment of cardiovascular insufficiency due to relative adrenal insufficiency in ill preterm and term newborn infants. Keywords: adrenocorticotropin; ACTH; adrenal insufficiency; corticotrophin-releasing hormone; cortisol; critically ill infants hypothalamic-pituitary-adrenal axis; newborns-full term Introduction Activation of the hypothalamic-pituitary-adrenal (HPA) axis and ultimate release of cortisol are critical in maintaining homeostasis in response to stress. Relative adrenal insufficiency occurs when the HPA axis produces insufficient cortisol for the degree of illness or stress. In some critically ill adult populations, relative adrenal insufficiency is prevalent, 1-4 and is associated with increased morbidity and mortality. 2,3,5 Some studies of glucocorticoid treatment in critically ill adults have shown benefit, with faster reversal of shock and reduction in mortality. 3,[5][6][7][8] Recently, increasing evidence supports the existence of relative adrenal insufficiency in ill newborns, but, similar to other ill populations, there remains no general consensus on which patients should be tested, which tests to use and how to interpret them, which patients should be treated or how they should be treated. 9 The following discussion is an overview of corticosteroid physiology, relative adrenal insufficiency in critically ill populations and evidence of its existence in newborn infants, with proposed underlying

Salivary and hair glucocorticoids and sleep in very preterm children during school age

“…Very preterm birth involves several adversities that could induce HPA axis programming: First, pregnancy-related aspects, such as maternal infections, inflammations, and prenatal stress, may influence both the risk of preterm birth and children's brain development (Buss et al, 2012;Goldenberg et al, 2008;Monk et al, 2016). Second, children born very preterm suffer from the immature functioning of the lungs, often leading to hypoxia (Saigal and Doyle, 2008) and the adrenal gland leading to potential adrenal insufficiency (Fernandez and Watterberg, 2009). Third, children born very preterm are exposed to many distressing medical procedures including blood draws and mechanical ventilation (Anand, 2001;Brummelte et al, 2015;Grunau et al, 2007).…”

Niveles de cortisol en la saliva y séricos en recién nacidos

“…17 Los bajos niveles de cortisol sérico en algunos de estos niños, probablemente, correspondan a algún fenómeno de inmadurez o tiempos diferentes de involución de la zona fetal adrenal asociados a los bajos niveles de hormona adrenocorticotropina (adrenocorticotropic hormone; ACTH, por sus siglas en inglés) y de la 3-β oldeshidrogenada, como ha sido descrito. [1][2][3] Se ha postulado que la placenta humana sintetiza grandes cantidades de hormona liberadora de corticotropina (corticotropin-releasing hormone; CRH, por sus siglas en inglés), que es liberada a la circulación materna y fetal, lo que resulta en las concentraciones de CRH más altas de la vida. Después del parto, ocurre una disminución abrupta de CRH circulante.…”

“…1 Más del 80% de la corteza de la glándula adrenal en el feto está constituida por la zona fetal que sintetiza, predominantemente, sulfato de dehidroepiandrosterona 1 y bajas concentraciones de cortisol, que se explican por la reducida actividad de la enzima 3-β ol-deshidrogenasa. [1][2][3] Luego del nacimiento, la corteza fetal involuciona de modo paulatino y, concomitantemente, se observa un aumento en la actividad de la enzima 3-β ol-deshidrogenasa.…”

Salivary and serum cortisol levels in newborn infants

“…17 It is likely that low serum cortisol levels in some of these infants correspond to a phenomenon of immaturity or to different disappearance times in the adrenal fetal zone associated with low adrenocorticotropic hormone (ACTH) and 3-β-oldehydrogenase levels, as described. [1][2][3] It has been postulated that the human placenta synthesizes large quantities of corticotropin-releasing hormone (CRH), which is released by maternal and fetal circulation resulting in the highest CRH concentrations in life. After birth, there is an abrupt decrease in circulating CRH.…”

“…1 In the fetus, over 80% of the adrenal cortex consists of the fetal zone that predominantly synthesizes dehydroepiandrosteronesulfate (DHEA-S) 1 and low cortisol levels, which account for 3-β-oldehydrogenase deficiency. [1][2][3] After birth, the fetal cortex progressively disappears and a concomitant increase in the activity of the enzyme 3-β-oldehydrogenase is observed.…”