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Pituitary-adrenal axis function in systemic inflammatory response syndrome
1Department of Medicine, Harbor-UCLA Medical Center, 90509, Torrance, California, USA.
Endocrine
|December 15, 2010
Summary
Systemic inflammatory response syndrome (SIRS) patients showed impaired adrenal responsiveness to ACTH, particularly those with bacteremia. This reduced cortisol response is a significant indicator of mortality in SIRS patients.
Area of Science:
- Endocrinology
- Critical Care Medicine
- Infectious Diseases
Background:
- The hypothalamic-pituitary-adrenal (HPA) axis is crucial for stress response.
- Sepsis, now known as SIRS, can significantly impact endocrine function.
- Adrenal insufficiency is a concern in critically ill patients.
Purpose of the Study:
- To evaluate HPA axis function in patients with SIRS.
- To determine the relationship between adrenal reserve and mortality in SIRS.
- To investigate the impact of bacteremia on adrenal responsiveness.
Main Methods:
- 113 SIRS patients underwent a 250 µg IV ACTH stimulation test.
- Serum cortisol levels were measured at baseline and 30, 60 minutes post-ACTH.
- Multivariate analysis assessed baseline and delta cortisol as mortality predictors.
Main Results:
- 28% overall mortality in the SIRS cohort.
- Baseline and delta cortisol concentrations were significant mortality indicators.
- Bacteremic patients exhibited a blunted cortisol response (delta cortisol) to ACTH compared to non-bacteremic patients.
Conclusions:
- Bacteremic processes may impair adrenal responsiveness to ACTH.
- Reduced adrenal reserve is linked to increased mortality in SIRS.
- Further research into pathophysiological disturbances could yield new treatment strategies for bacteremia.
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