title: Hypothalamic-pituitary hormones during critical illness: a dynamic neuroendocrine response.
abstract: Independent of the underlying condition, critical illness is characterized by a uniform dysregulation of the hypothalamic-pituitary-peripheral axes. In most axes a clear biphasic pattern can be distinguished. The acute phase of critical illness is characterized by low peripheral effector hormone levels such as T3, IGF-1 and testosterone, despite an actively secreting pituitary. The adrenal axis with high cortisol levels in the presence of low ACTH levels is a noteworthy exception. In the prolonged phase of critical illness, low peripheral effector hormone levels coincide with a uniform suppression of the neuroendocrine axes, predominantly of hypothalamic origin. The severity of the alterations in the different neuroendocrine axes is associated with a high risk of morbidity and mortality, but it remains unknown whether the observed changes are cause or consequence of adverse outcome. Several studies have identified therapeutic potential of hypothalamic releasing factors, but clinical outcome remains to be investigated with sufficiently powered randomized controlled trials.
authors.affiliation: Laboratory and Department of Intensive Care Medicine, University of Leuven, Leuven, Belgium. Electronic address: lies.langouche@med.kuleuven.be.
authors.forename: Lies
authors.initials: L
authors.lastname: Langouche
authors.affiliation: Laboratory and Department of Intensive Care Medicine, University of Leuven, Leuven, Belgium.
authors.forename: Greet
authors.initials: G
authors.lastname: Van den Berghe
mesh_terms: D000818:Animals; D016638:Critical Illness / Q000628:therapy; D006801:Humans; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism*; D009489:Neurosecretion / Q000502:physiology*; D009490:Neurosecretory Systems / Q000378:metabolism; D010907:Pituitary Hormones / Q000378:metabolism* / Q000627:therapeutic use; D010913:Pituitary-Adrenal System / Q000378:metabolism*
chemical_list: D010907:Pituitary Hormones
keywords: Critical illness; cortisol; endocrine changes; gonadal; growth hormone; prolactin; therapeutic implications; thyroid