scholarly journals Hypothalamic-pituitary-adrenal axis in lethal canine Staphylococcus aureus pneumonia

2014 ◽  
Vol 307 (11) ◽  
pp. E994-E1008 ◽  
Author(s):  
Irene Cortés-Puch ◽  
Caitlin W. Hicks ◽  
Junfeng Sun ◽  
Steven B. Solomon ◽  
Peter Q. Eichacker ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Septic Shock ◽  
Hpa Axis ◽  
Strong Relationship ◽  
High Dose ◽  
Acth Stimulation ◽  
Hypothalamic Pituitary Adrenal ◽  
Free Cortisol ◽  
Poor Outcomes ◽  
Staphylococcus Aureus Pneumonia

The clinical significance and even existence of critical illness-related corticosteroid insufficiency is controversial. Here, hypothalamic-pituitary-adrenal (HPA) function was characterized in severe canine Staphylococcus aureus pneumonia. Animals received antibiotics and titrated life-supportive measures. Treatment with dexamethasone, a glucocorticoid, but not desoxycorticosterone, a mineralocorticoid, improves outcome in this model. Total and free cortisol, adrenocorticotropic hormone (ACTH). and aldosterone levels, as well as responses to exogenous ACTH were measured serially. At 10 h after the onset of infection, the acute HPA axis stress response, as measured by cortisol levels, exceeded that seen with high-dose ACTH stimulation but was not predictive of outcome. In contrast to cortisol, aldosterone was largely autonomous from HPA axis control, elevated longer, and more closely associated with survival in early septic shock. Importantly, dexamethasone suppressed cortisol and ACTH levels and restored ACTH responsiveness in survivors. Differing strikingly, nonsurvivors, sepsis-induced hypercortisolemia, and high ACTH levels as well as ACTH hyporesponsiveness were not influenced by dexamethasone. During septic shock, only serial measurements and provocative testing over a well-defined timeline were able to demonstrate a strong relationship between HPA axis function and prognosis. HPA axis unresponsiveness and high aldosterone levels identify a septic shock subpopulation with poor outcomes that may have the greatest potential to benefit from new therapies.

scholarly journals Post-surgical hypocortisolism after removal of an adrenal incidentaloma: is it predictable by an accurate endocrinological work-up before surgery?

2010 ◽  
Vol 162 (1) ◽  
pp. 91-99 ◽  
Author(s):  
Cristina Eller-Vainicher ◽  
Valentina Morelli ◽  
Antonio Stefano Salcuni ◽  
Massimo Torlontano ◽  
Francesca Coletti ◽  
...  
Keyword(s):  
Hpa Axis ◽  
Adrenal Incidentaloma ◽  
Serum Cortisol ◽  
Urinary Free Cortisol ◽  
Tolerance Test ◽  
Surgical Removal ◽  
Acth Stimulation ◽  
Unilateral Adrenalectomy ◽  
Free Cortisol ◽  
Few Data

ObjectiveFew data are available regarding the need of steroid substitutive therapy after unilateral adrenalectomy for adrenal incidentaloma (AI). It is unknown whether, before surgery, the hypothalamic–pituitary–adrenal (HPA) axis secretion parameters can predict post-surgical hypocortisolism.AimThis study aimed to evaluate whether, in AI patients undergoing unilateral adrenalectomy, post-surgical hypocortisolism could be predicted by the parameters of HPA axis function.DesignProspective, multicenter.MethodsA total of 60 patients underwent surgical removal of AI (surgical indication: 29 subclinical hypercortisolism (SH); 31 AI dimension). Before surgery, SH was diagnosed in patients presenting at least three criteria out of urinary free cortisol (UFC) levels>60 μg/24 h, cortisol after 1-mg dexamethasone suppression test (1 mg-DST)>3.0 μg/dl, ACTH levels<10 pg/ml, midnight serum cortisol (MSC)>5.4 μg/dl.Two months after surgery, HPA axis function was assessed by low dose ACTH stimulation test or insulin tolerance test when needed: 39 patients were affected (Group B) and 21 were not affected (Group A) with hypocortisolism. The accuracy in predicting hypocortisolism of pre-surgical HPA axis parameters or their combinations was evaluated.ResultsThe presence of >2 alterations among 1 mg-DST>5.0 μg/dl, ACTH<10 pg/ml, elevated UFC and MSC has the highest odds ratio (OR) for predicting post-surgical hypocortisolism (OR 10.45, 95% confidence interval, CI 2.54–42.95, P=0.001). Post-surgical hypocortisolism was predicted with 100% probability by elevated UFC plus MSC levels, but not ruled out even in the presence of the normality of all HPA axis parameters.ConclusionPost-surgical hypocortisolism cannot be pre-surgically ruled out. A steroid substitutive therapy is indicated after unilateral adrenalectomy for SH or size of the adenoma.

scholarly journals Aldosterone secretion in patients with septic shock: a prospective study

2013 ◽  
Vol 57 (8) ◽  
pp. 636-641 ◽  
Author(s):  
Rafael Barberena Moraes ◽  
Gilberto Friedman ◽  
Marina Verçoza Viana ◽  
Tiago Tonietto ◽  
Henrique Saltz ◽  
...  
Keyword(s):  
Septic Shock ◽  
Serum Levels ◽  
Zona Glomerulosa ◽  
High Dose ◽  
Zona Fasciculata ◽  
Cortisol Secretion ◽  
Aldosterone Secretion ◽  
Acth Stimulation ◽  
Aldosterone Production ◽  
A Prospective Study

OBJECTIVE: To assess serum levels of the main factors that regulate the activation of the zona glomerulosa and aldosterone production in patients with septic shock, as well as their response to a high-dose (250 µg) adrenocorticotropic hormone (ACTH) stimulation test. SUBJECTS AND METHODS: In 27 patients with septic shock, baseline levels of aldosterone, cortisol, ACTH, renin, sodium, potassium, and lactate were measured, followed by a cortrosyn test. RESULTS: Renin correlated with baseline aldosterone and its variation after cortrosyn stimulation. Baseline cortisol and its variation did not correlate with ACTH. Only three patients had concomitant dysfunction of aldosterone and cortisol secretion. CONCLUSIONS: Activation of the zona glomerulosa and zona fasciculata are independent. Aldosterone secretion is dependent on the integrity of the renin-angiotensin-aldosterone system, whereas cortisol secretion does not appear to depend predominantly on the hypothalamic-pituitary-adrenal axis. These results suggest that activation of the adrenal gland in critically ill patients occurs by multiple mechanisms.

Neuroimmunological Effects of Exposure to Methylmercury Forms in the Sprague-Dawley Rats. Activation of the Hypothalamic-Pituitary-Adrenal Axis and Lymphocyte Responsiveness

1997 ◽  
Vol 13 (1) ◽  
pp. 57-66 ◽  
Author(s):  
Hector G. Ortega ◽  
Manuel Lopez ◽  
Atsushi Takaki ◽  
Qin-Heng Huang ◽  
Akira Arimura ◽  
...  
Keyword(s):  
Hpa Axis ◽  
Low Dose ◽  
Fold Increase ◽  
Exposed Group ◽  
Blood Levels ◽  
High Dose ◽  
Sprague Dawley ◽  
Short Term ◽  
Hypothalamic Pituitary Adrenal ◽  
Short Term Exposure

The effects of different methylmercury (MeHg) forms on the immune system and the hypothalamic pituitary adrenal (HPA) axis were assessed. The lymphocyte response to Concanavalin A (Con A) stimulation, blood levels of interleukin-6 (IL-6), adrenocorticotrophin hormone (ACTH), and corticosterone in the presence of different MeHg compounds was measured. Rats were exposed to methylmercury sulfide [(MeHg)2S] and methylmercury chloride (MeHgCl) at concentrations of 5 and 500 μg per liter in the drinking water for 8 or 16 weeks. Short-term exposure (8 weeks) at both, low- and high-doses of (MeHg)2S significantly enhanced lymphocyte responsiveness. MeHgCl only induced increased lymphocyte responsiveness at the low-dose exposure. Circulating levels of IL-6 after short-term exposure were increased in the MeHgCl-exposed group. The HPA axis activation was demonstrated by increased levels of ACTH and corticosterone levels. This response was predominant in low-dose exposed animals. Long-term (16 weeks) exposure resulted in a reduction in lymphocyte proliferation after both low- and high-dose MeHgCl exposures. The (MeHg)2S exposure resulted in a 3-fold increase in the proliferative response. Levels of ACTH were elevated 3-fold in the (MeHg)2S-exposed group, and no increase of corticosterone was observed in the high-dose exposed group at 8 weeks, no effect of(MeHg)2S was observed at 16 weeks. The MeHgCl exposed group showed an increase in ACTH and corticosterone levels at 8 weeks; this response was not observed at 16 weeks. These data indicate that exposure to MeHg compounds enhances T-cell proliferation in most of the cases, in a dose- and time-dependent fashion. Release of IL-6 also depends on the length of exposure. Early increases in circulating ACTH at 8 weeks also suggest activation of the HPA axis. This may contribute to the production of IL-6 and surveillance of regulatory homeostatic responses against environmental agents that mimic stress-like responses.

scholarly journals Effects of Twinning and Periconceptional Undernutrition on Late-Gestation Hypothalamic-Pituitary-Adrenal Axis Function in Ovine Pregnancy

Endocrinology ◽  
2007 ◽  
Vol 149 (3) ◽  
pp. 1163-1172 ◽  
Author(s):  
C. W. H. Rumball ◽  
M. H. Oliver ◽  
E. B. Thorstensen ◽  
A. L. Jaquiery ◽  
S. M. Husted ◽  
...  
Keyword(s):  
Hpa Axis ◽  
Disease Risk ◽  
Area Under The Curve ◽  
Late Gestation ◽  
Acth Stimulation ◽  
Direct Stimulation ◽  
Hypothalamic Pituitary Adrenal ◽  
Adult Disease ◽  
Increased Risk ◽  
Size At Birth

The relationships between reduced size at birth, increased activity of the hypothalamic-pituitary-adrenal (HPA) axis, and increased risk of disease in adulthood are well described in singletons but are much less clear in twins. This may be because the physiological processes underlying reduced size at birth are different in singletons and twins. Periconceptional undernutrition can cause altered activity of the fetal and postnatal HPA axis without altering size at birth. However, the independent effects of periconceptional undernutrition and twinning on activity of the maternal and fetal HPA axes are not well described. We therefore studied maternal and fetal HPA axis function during late gestation in twin and singleton sheep pregnancies, either undernourished around conception or fed ad libitum. We found that twinning led to suppressed baseline HPA axis function and decreased adrenal sensitivity to ACTH stimulation but increased fetal pituitary ACTH response both to direct stimulation by CRH (ACTH area under the curve response: 29.7 ± 2.2 vs. 17.1 ± 1.6 ng/min·ml, P &lt; 0.01) and to decreased cortisol negative feedback. In contrast, periconceptional undernutrition resulted in a decreased pituitary response (ACTH area under the curve response: 19.4 ± 1.6 vs. 26.1 ± 2.2 ng/min·ml, P = 0.02) but no difference in adrenal response. Thus, the HPA axis function of twin sheep fetuses in late gestation is very different from that of control and undernourished singletons. If the HPA axis is an important mediator between fetal adaptations and adult disease, these data may help explain why the relationship between fetal growth and postnatal physiology and disease risk is inconsistent in twins.

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