Mechanisms and clinical consequences of critical illness associated adrenal insufficiency

Adrenal insufficiency in liver diseases - pathophysiology and underlying mechanisms

Relative adrenal insufficiency (RAI) is common in critically ill patients with cirrhosis, but it has been also documented in non-critically ill patients. Its pathophysiology is complex and not well understood yet. In this review, we aimed to present potential mechanisms and causal pathways implicated in the pathogenesis of RAI in cirrhosis. There is accumulating evidence supporting a suboptimal baseline adrenal function in cirrhosis mainly due to decreased cortisol synthesis and metabolism rates from the adrenal gland. Apart from this peripheral impairment, more recent studies suggest that there is a greater defect in the central stimulation of the hypothalamic-pituitary-adrenal (HPA) axis (hypothalamus/pituitary gland). Pro-inflammatory mediators, which are elevated in cirrhosis, have been also implicated through suppression of the HPA axis, decrease in cortisol synthesis and tissue glucocorticoid resistance. All abovementioned support the hepatoadrenal syndrome hypothesis that during episodes of acute decompensation there is suboptimal adrenocortical response that leads to worse outcomes. In conclusion, the complex pathophysiology of adrenal dysfunction in cirrhosis has not been fully elucidated yet and further research is needed in order to better understand this rather common entity in cirrhosis.

Critical illness-related corticosteroid insufficiency (CIRCI) in paediatric patients: a diagnostic and therapeutic challenge

Critical illness-related corticosteroid insufficiency or CIRCI is characterized by acute and life-threatening disfunction of hypothalamic-pituitary-adrenal (HPA) axis observed among intensive care unit- staying patients.It is associated with increased circulating levels of biological markers of inflammation and coagulation, morbidity, length of ICU stay, and mortality.Several mechanisms are involved in CIRCI pathogenesis: reduced CRH-stimulated ACTH release, peripheral resistance to glucocorticoids, altered cortisol synthesis, impaired cortisol-free fraction and bioavailability.Diagnostic and therapeutic management of this condition in children is still debated, probably because of the lack of agreement among intensive care specialists and endocrinologists regarding diagnostic criteria and prevalence of CIRCI in paediatric age.In the present narrative review, we focused on definition of CIRCI in paediatric age and we advise on how to diagnose and treat this poorly understood condition, based on current literature data.

Low Urinary Free Cortisol as a Risk Factor for Patients with Variceal Bleeding

Background and Objectives: Specificity and reliability issues of the current cortisol assessment methods lead to limitations on the accurate assessment of relative adrenal insufficiency. Although free cortisol provides a more accurate evaluation of adrenal cortisol production, the expense and time-consuming nature of these assays make them impractical for routine use. Research has, thus, focused on alternative methods, such as indirectly measuring free cortisol using Coolens' equation or directly assessing salivary cortisol concentration, which is considered a more favorable approach despite associated challenges like sampling issues and infection risks. The aim of this study was to explore correlations between 24 h urinary free cortisol (UFC), free plasma cortisol, serum total cortisol, and salivary cortisol as potential reliable indices of free cortisol in the setting of variceal bleeding. Additionally, we assessed the predictive value of UFC for 6-week mortality and 5-day treatment failure in patients with liver cirrhosis and variceal bleeding. Materials and Methods: A total of 40 outpatients with liver cirrhosis and variceal bleeding were enrolled. Free cortisol levels in serum, saliva, and urine were assessed using the electrochemiluminescence immunoassay method. For the measurement of plasma-free cortisol, a single quadrupole mass spectrometer was employed. The quantification of free cortisol was fulfilled by analyzing the signal response in the negative ESI-MS mode. Results: UFC was significantly correlated to free plasma cortisol. Negative correlations were demonstrated between UFC, the Child-Pugh (CP) score, and C reactive protein (CRP) levels. In the multivariate analysis, CP stage C was associated with 6-week mortality risk and portal vein thrombosis with 5-day treatment failure using Cox regression and binary logistic regression analyses, respectively. Patients who experienced rebleeding, infection, or death (or any combination of these events) presented with lower levels of UFC. Conclusions: This study suggests that low levels of UFC may impose a risk factor for patients with liver cirrhosis and variceal bleeding. The use of UFC as an index of adrenal cortisol production in variceal bleeding warrants further investigation.

Reduced hydrogen sulfide production contributes to adrenal insufficiency induced by hypoxia via modulation of NLRP3 inflammasome activation

Objective: Adrenocortical responsiveness is critical for maintaining glucocorticoids production and homeostasis during stress. We sought to investigate adrenocortical responsiveness during hypoxia in mice and the mechanisms responsible for the regulation of adrenal responsiveness.Methods: (1) Adult male WT mice were randomly divided into four groups: normoxia, hypoxia (24h), hypoxia (72h), hypoxia (72h) + GYY4137(hydrogen sulfide (H₂S) donor, 133mmol/kg/day); (2) WT mice were randomly divided into four groups: sham, adrenalectomy (ADX), sham+hypoxia, ADX+hypoxia; (3) Cse^-/- mice were randomly divided into two groups: Cse^-/-, Cse^-/- +GYY4137.Results: The circulatory level of corticosteroid induced by ACTH stimulation was significantly reduced in the mice with hypoxia compared with control mice. The mortality rate induced by lipopolysaccharide (LPS) increased during hypoxia. Cystathionine-γ-lyase (CSE) expression was significantly reduced in adrenal glands during hypoxia. GYY4137 treatment significantly increased adrenal responsiveness and attenuated NLRP3 inflammasome activation in mice treated by hypoxia and Cse^-/- mice. Furthermore, The sulfhydrated level of PSMA7 in adrenal gland was decreased in the mice with hypoxia and Cse^-/- mice. PSMA7 was S-sulfhydrated at cysteine 70. Blockage of S-sulfhydration of PSMA7 increased NLRP3 expression in adrenocortical cells.Conclusion: Reduced H₂S production mediated hypo-adrenocortical responsiveness and NLRP3 inflammasome activation via PAMA7 S-sulfhydration during hypoxia.

A Cross-Sectional Survey Study on the Diagnosis and Management of Critical Illness-Induced Corticosteroid Insufficiency in Saudi Arabia

Background The presence of critical illness-induced corticosteroid insufficiency (CIRCI) is correlated with elevated concentrations of circulating biomarkers associated with inflammation and coagulation in multiple domains. The management of adrenal insufficiency remains a topic of ongoing debate and disagreement among endocrinologists and intensivists. This study aimed to assess the extent of understanding regarding CIRCI among endocrinologists and intensivists who are actively practicing in Saudi Arabia. Methods This is an online cross-sectional survey study that was conducted between June and August 2023 to assess knowledge of CIRCI among endocrinologists and intensivists working in Saudi Arabia. The questionnaire tool for this study was constructed based on a previous literature review. Binary logistic regression analysis was used to define factors that affect participants' knowledge of CIRCI. Results A total of 76 physicians were involved in this study. Around 32.9% (n= 25) of the participants described CIRCI correctly as an impairment of the hypothalamic-pituitary axis during critical illness. Around 35.5% (n=27) of the participants identified that widespread use of corticosteroids in critically ill patients prompted the need to revisit the concept, diagnosis, and management of CIRCI, and a similar proportion of the participants (35.5%) (n=27) identified that the role of corticosteroids in the management of CIRCI in critically ill patients may be beneficial in selected cases. Around 42.1% (n=32) of the participants identified that CIRCI is specific to critically ill patients while AI can occur in any individual. Around 17.1% (n=13) of the participants confirmed that there is no task force agreement on whether corticosteroids should be used in adult patients with sepsis but without shock. The mean knowledge score of the study participants was 3.6 (sd: 2.2) out of 10, which demonstrates a weak level of knowledge of CIRCI (36.0%). Binary logistic regression analysis identified that physicians from the southern and western regions were less likely to be knowledgeable of CIRCI compared to physicians from the central region (p< 0.05). Conclusion The study revealed that the level of familiarity with CIRCI among endocrinologists and intensivists in Saudi Arabia fell short of the desired benchmark. Clinicians may opt to utilize delta cortisol levels following cosyntropin administration and random plasma cortisol levels as diagnostic measures for CIRCI, instead of relying on plasma-free cortisol or salivary cortisol levels in conjunction with plasma total cortisol. Adherence to customized treatment protocols is crucial to attain the most favorable results for patients.

The ultra-acute steroid response to traumatic injury: a cohort study

OBJECTIVE

Trauma-induced steroid changes have been studied post-hospital admission, resulting in a lack of understanding of the speed and extent of the immediate endocrine response to injury. The Golden Hour study was designed to capture the ultra-acute response to traumatic injury.

DESIGN

We conducted an observational cohort study including adult male trauma patients <60 years, with blood samples drawn ≤1 h of major trauma by pre-hospital emergency responders.

METHODS

We recruited 31 adult male trauma patients (mean age 28 [range 19-59] years) with a mean injury severity score (ISS) of 16 (IQR 10-21). The median time to first sample was 35 (range 14-56) min, with follow-up samples collected 4-12 and 48-72 h post-injury. Serum steroids in patients and age- and sex-matched healthy controls (HCs) (n = 34) were analysed by tandem mass spectrometry.

RESULTS

Within 1 h of injury, we observed an increase in glucocorticoid and adrenal androgen biosynthesis. Cortisol and 11-hydroxyandrostendione increased rapidly, whilst cortisone and 11-ketoandrostenedione decreased, reflective of increased cortisol and 11-oxygenated androgen precursor biosynthesis by 11β-hydroxylase and increased cortisol activation by 11β-hydroxysteroid dehydrogenase type 1. Active classic gonadal androgens testosterone and 5α-dihydrotestosterone decreased, whilst the active 11-oxygenated androgen 11-ketotestosterone maintained pre-injury levels.

CONCLUSIONS

Changes in steroid biosynthesis and metabolism occur within minutes of traumatic injury. Studies that address whether ultra-early changes in steroid metabolism are associated with patient outcomes are now required.

Single-cell atlas of murine adrenal glands reveals immune-adrenal crosstalk during systemic <i>Candida albicans</i> infection

Fungal sepsis remains a major health threat with high mortality, where the adrenal gland stress response has been rarely reported. <i>Candida albicans</i> (<i>C.albicans</i>) is the most common opportunistic fungal pathogen of life-threatening disseminated candidiasis and fungal sepsis. In the present study, we performed single-cell RNA sequencing (scRNA-Seq) using the 10x Genomics platform to analyze the changes in murine adrenal transcriptome following systemic <i>C.albicans</i> infection. A total of 16 021 cells were categorized into 18 transcriptionally distinct clusters, representing adrenocortical cells, endothelial cells, various immune cells, mesenchymal cells, smooth muscle cells, adrenal capsule, chromaffin cells, neurons and glials. As the main cell component in the adrenal gland responsible for steroidogenesis, the adrenocortical cells dramatically diminished and were further grouped into 10 subclusters, which differently distributed in the infected and uninfected samples. Pseudo-time analysis revealed transitions of the adrenocortical cells from the initial normal states to active or dysfunctional states following systemic <i>C.albicans</i> infection <i>via</i> two trajectory paths. Endothelial cells in the highly vascularized organ of adrenal gland further proliferated following infection, with the upregulation of genes positively regulating angiogenesis and downregulation of protective genes of endothelial cells. Immune cells were also excessively infiltrated in adrenal glands of <i>C.albicans</i>-infected mice. Macrophages dominated the immune microenvironments in murine adrenal glands both before and after <i>C.albicans</i> infection, mediating the crosstalk among the steroid-producing cells, endothelial cells and immune cells within the adrenal gland. NLR family, pyrin domain containing 3 (NLRP3, encoded by <i>Nlrp3</i>) and complement receptor 3 (CR3, encoded by <i>Itgam</i>) were found to be significantly upregulated on the adrenal macrophages upon systemic <i>C.albicans</i> infection and might play critical roles in mediating the myeloid response. Meanwhile, the number and strength of the interactions between the infiltrating immune cells and adrenal resident cells were unveiled by cell-cell communication analysis to be dramatically increased after systemic <i>C.albicans</i> infection, indicating that the immune-adrenal crosstalk might contribute to the compromised functions of adrenal cells. Overall, our comprehensive picture of the murine adrenal gland microenvironment in systemic <i>C.albicans</i> infection provides deeper insights into the immune-adrenal cell communications during fungal sepsis.

To protect or to kill: A persisting Darwinian immune dilemma

The immune system, which evolved as a protective system, can paradoxically mediate lethal effects when it is over-activated. These effects can be traced back to infected insects and are mainly mediated by phylogenetically old cytokines that have been found already in starfishes and sponges. We hypothesize that these anti-homeostatic effects are important for restricting the cumulative risk of transmission of highly mutating environmental pathogens that may endanger species, particularly when they start to originate and expand. Considering the Darwinian view that evolution is a permanent process, this anti-homeostatic program is preserved and expressed even when there is no risk for the species. Here, we review these aspects and discuss how evolutionary-imposed anti-homeostatic immune programs are expressed during acute and chronic human diseases, which can be further aggravated in the absence of medical interventions. The relevance of early identification of ancestral biomarkers that predict a shift from protective to deleterious immune outcomes is emphasized.

Perspective: Drawing on Findings From Critical Illness to Explain Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

We propose an initial explanation for how myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) could originate and perpetuate by drawing on findings from critical illness research. Specifically, we combine emerging findings regarding (a) hypoperfusion and endotheliopathy, and (b) intestinal injury in these illnesses with our previously published hypothesis about the role of (c) pituitary suppression, and (d) low thyroid hormone function associated with redox imbalance in ME/CFS. Moreover, we describe interlinkages between these pathophysiological mechanisms as well as “vicious cycles” involving cytokines and inflammation that may contribute to explain the chronic nature of these illnesses. This paper summarizes and expands on our previous publications about the relevance of findings from critical illness for ME/CFS. New knowledge on diagnostics, prognostics and treatment strategies could be gained through active collaboration between critical illness and ME/CFS researchers, which could lead to improved outcomes for both conditions.

Pharmacokinetics of thiamine (vitamin B1) in adult horses after administration of three single intravenous doses

Thiamine is a vital co-factor for several anti-inflammatory and antioxidant processes that are critical for mitigation of sepsis-associated inflammation, but pharmacokinetic (PK) analysis has not been reported in horses. We hypothesized that IV thiamine hydrochloride (TH) at increasing dosages would result in corresponding increases in plasma thiamine concentrations without causing adverse effects. A randomized cross-over study was performed in 9 healthy horses that each received TH at 5, 10, and 20 mg/kg IV. Blood was collected immediately prior to drug administration and at several time points thereafter. High-performance liquid chromatography with mass spectrometry was used to quantify thiamine concentrations at each time point. Non-compartmental PK methods showed that IV TH resulted in supraphysiologic plasma concentrations with a short half-life (0.77-1.12 h) and no adverse clinical signs were observed. The terminal rate constant decreased as the dosage increased (p < .0001) and clearance significantly decreased at the 20 mg/kg dosage (p = .0011). The area under the curve (AUC) increased in a non-linear fashion. These findings suggest that thiamine follows non-linear elimination kinetics in horses, which is likely due to saturation of renal elimination. Future studies are needed to identify therapeutic plasma concentrations and develop thiamine dosing recommendations for horses.

Theory: Treatments for Prolonged ICU Patients May Provide New Therapeutic Avenues for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

We here provide an overview of treatment trials for prolonged intensive care unit (ICU) patients and theorize about their relevance for potential treatment of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Specifically, these treatment trials generally target: (a) the correction of suppressed endocrine axes, notably through a "reactivation" of the pituitary gland's pulsatile secretion of tropic hormones, or (b) the interruption of the "vicious circle" between inflammation, oxidative and nitrosative stress (O&NS), and low thyroid hormone function. There are significant parallels in the treatment trials for prolonged critical illness and ME/CFS; this is consistent with the hypothesis of an overlap in the mechanisms that prevent recovery in both conditions. Early successes in the simultaneous reactivation of pulsatile pituitary secretions in ICU patients-and the resulting positive metabolic effects-could indicate an avenue for treating ME/CFS. The therapeutic effects of thyroid hormones-including in mitigating O&NS and inflammation and in stimulating the adreno-cortical axis-also merit further studies. Collaborative research projects should further investigate the lessons from treatment trials for prolonged critical illness for solving ME/CFS.

Hypothesis: Mechanisms That Prevent Recovery in Prolonged ICU Patients Also Underlie Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Here the hypothesis is advanced that maladaptive mechanisms that prevent recovery in some intensive care unit (ICU) patients may also underlie Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Specifically, these mechanisms are: (a) suppression of the pituitary gland's pulsatile secretion of tropic hormones, and (b) a "vicious circle" between inflammation, oxidative and nitrosative stress (O&NS), and low thyroid hormone function. This hypothesis should be investigated through collaborative research projects.

Low glucocorticoids in stress-related disorders: the role of inflammation

There is evidence that plasma cortisol concentration can be either increased or decreased in patients with depression and related anxiety and stress-related disorders; the exact pathophysiological mechanisms of this state are not almost clear. Several distinct theories were proposed and mechanisms, which could lead to decreased glucocorticoid signaling and/or levels, were described. However, there is a possible drawback in almost all the theories proposed: insufficient attention to the inflammatory process, which is undoubtedly present in several stress-related disorders, including post-traumatic stress disorder (PTSD). Previous studies only briefly mentioned the presence of an inflammatory reaction's signs in PTSD, without giving it due importance, although recognizing that it can affect the course of the disease. With that, the state of biochemical changes, characterized by the low glucocorticoids, glucocorticoid receptor's resistance and the signs of the persistent inflammation (with the high levels of circulating cytokines) might be observed not only in PTSD but in coronary heart diseases and systemic chronic inflammatory diseases (rheumatoid arthritis) as well. That is why the present review aims to depict the pathophysiological mechanisms, which lead to a decrease in glucocorticoids in PTSD due to the action of inflammatory stimuli. We described changes in the glucocorticoid system and inflammatory reaction as parts of an integral system, where glucocorticoids and the glucocorticoid receptor reside at the apex of a regulatory network that blocks several inflammatory pathways, while decreased glucocorticoid signaling and/or level leads to unchecked inflammatory reactions to promote pathologies such as PTSD. LAY SUMMARY This review emphasizes the importance of inflammatory reaction in the development of puzzling conditions sometimes observed in severe diseases including post-traumatic stress disorder - the decreased levels of glucocorticoids in the blood. Following the classical concepts, one would expect an increase in glucocorticoid hormones, since they are part of the feedback mechanism in the immune system, which reduces stress and inflammation. However, low levels of glucocorticoid hormones are also observed. Thus, this review describes potential mechanisms, which can lead to the development of such a state.

Effects of administration of ascorbic acid and low-dose hydrocortisone after infusion of sublethal doses of lipopolysaccharide to horses

Background

Sepsis is associated with ascorbic acid (AA) depletion and critical illness‐related corticosteroid insufficiency (CIRCI) in humans.

Hypotheses

Intravenous infusion of lipopolysaccharide (LPS) would (a) decrease endogneous AA concentrations, (b) induce CIRCI and (c) administration of a combination of AA and hydrocortisone (HC) would have decreased indices of inflammation compared to either drug alone.

Animals

Thirty‐two healthy horses.

Methods

Randomized placebo‐controlled experimental trial. Horses were assigned to 1 of 4 groups (saline, AA and HC, AA only, or HC only). Treatments were administered 1 hour after completion of LPS infusion. Clinical signs, clinicopathological variables, pro‐inflammatory cytokine gene expression and production, and plasma AA concentrations were assessed at various time points. Serum cortisol concentrations and ACTH stimulation tests were used to detect CIRCI.

Results

There was no effect of drug on clinical signs or pro‐inflammatory cytokine gene expression or production compared to controls at any time point. Administration of AA was associated with higher blood neutrophil counts 6 hours after LPS infusion (11.01 ± 1.02 K/μl) compared to other groups (8.99 ± 0.94 K/μL; P < .009). Adminstration of HC was associated with higher blood neutrophil counts 12 hours after LPS infusion (10.40 ± 0.75 K/μl) compared to other groups (6.88 ± 0.68 K/μl; P < .001). Serum cortisol increased from 5.11 ± 1.48 μg/dL before LPS administration to 9.59 ± 1.83 μg/dL 1 h after completion of LPS infusion (T1) without an effect of treatment (P = 0.59).

Conclusions and Clinical Importance

Ascorbic acid and HC appeared to protect against LPS‐induced neutrophil depletion and could be considered as adjunctive therapy in horses with endotoxemia.

The Adrenal Cortex, an Underestimated Site of SARS-CoV-2 Infection

BACKGROUND

The majority of the critically ill patients may have critical illness-related corticosteroid insufficiency (CIRCI). The therapeutic effect of dexamethasone may be related to its ability to improve cortical function. Recent study showed that dexamethasone can reduce COVID-19 deaths by up to one third in critically ill patients. The aim of this article is to investigate whether SARS-CoV-2 can attack the adrenal cortex to aggravate the relative adrenal insufficiency.

METHODS

We summarized the clinical features of COVID-19 reported in currently available observational studies. ACE2 and TMPRSS2 expression was examined in human adrenal glands by immunohistochemical staining. We retrospectively analyzed serum cortisol levels in critically ill patients with or without COVID-19.

RESULTS

High percentage of critically ill patients with SARS-COV-2 infection in the study were treated with vasopressors. ACE2 receptor and TMPRSS2 serine protease were colocalized in adrenocortical cells in zona fasciculata and zona reticularis. We collected plasma cortisol concentrations in nine critically ill patients with COVID-19. The cortisol levels of critically ill patients with COVID-19 were lower than those in non-COVID-19 critically ill group. Six of the nine COVID-19 critically ill patients had random plasma cortisol concentrations below 10 µg/dl, which met the criteria for the diagnosis of CIRCI.

CONCLUSION

We demonstrate that ACE2 and TMPRSS2 are colocalized in adrenocortical cells, and that the cortisol levels are lower in critically ill patients with COVID-19 as compared to those of non-COVID-19 critically ill patients. Based on our findings, we recommend measuring plasma cortisol level to guide hormonal therapy.

RNA-seq analysis of LPS-induced transcriptional changes and its possible implications for the adrenal gland dysregulation during sepsis

Activation of the adrenal gland stress response is of utmost importance to survive sepsis. Experimental and clinical evidence exists demonstrating that adrenal gland often develops functional and structural damage due to sepsis with mechanisms remaining largely unknown. In the present study, we have used RNA Sequencing (RNA-Seq) technology to analyze changes in adrenal transcriptome elucidated by bacterial LPS. We aimed to find particularly alterations in genes that were previously not reported to be involved in the adrenal gland dysregulation in contexts of sepsis. Our results demonstrate that systemic administration of LPS significantly altered expression of 8458 genes as compared to saline injected animals. The subsequent quality and functional analysis of these gene signatures revealed that LPS-induced highly homogenous transcriptional response in total upregulating 4312 and downregulating 4146 genes. Furthermore, functional annotation analysis together with gene enrichment set analysis (GSEA) clearly demonstrated that adrenal response to LPS involved alterations in multiple pathways related to the inflammatory response along with previously unexplored activation of the hypoxia pathway. In addition, LPS strongly downregulated genes involved in the adrenal homeostasis, development, and regeneration. Those alterations were subsequently verified in clinically relevant cecal ligation and puncture (CLP)-induced sepsis model. Collectively, our study demonstrates that RNA-seq is a very useful method that can be applied to search for new unexplored pathways potentially involved in adrenal gland dysregulation during sepsis.

The hollow adrenal gland sign: a newly described enhancing pattern of the adrenal gland on dual-phase contrast-enhanced CT for predicting the prognosis of patients with septic shock

OBJECTIVE

To investigate the incidence, CT appearance, and implication for prognosis of the hollow adrenal gland sign (HAGS).

METHODS

A total of 194 patients with septic shock and 24 patients with hemorrhagic shock (as control group) were retrospectively included in this study and the patients with septic shock were further divided into four subgroups (digestive tract diseases, DTD, n = 49; biliary and pancreatic diseases, BPD, n = 41; postsurgical infection, PI, n = 64; and other diseases, OD, n = 40). All patients underwent a dual-phase contrast-enhanced CT within 1 week after diagnosis. CT findings and clinical records were reviewed. If in the arterial phase the central zone of adrenal gland showed temporally much lower attenuation than the peripheral zone, it was defined as HAGS positive. The incidence of the HAGS in patients with septic shock and hemorrhagic shock, the demographic features, and mortality between HAGS-positive and HAGS-negative patients in each group were respectively compared.

RESULTS

The incidence of the HAGS in the septic shock group was nearly 30%, while it was 0 in the hemorrhagic shock group. There was no significant difference in age or gender between HAGS-positive and HAGS-negative patients in all groups, while the mortality of HAGS-positive patients was significantly higher than that of HAGS-negative patients in each group (p < 0.05). The concordance correlation coefficient value showed excellent reproducibility of the two observers (κ = 0.977).

CONCLUSION

The HAGS is specific and common on dual-phase contrast-enhanced CT in patients with septic shock and predicts a poor prognosis.

KEY POINTS

• The hollow adrenal gland sign (HAGS) newly described in this study is a special enhancing pattern of adrenal gland on dual-phase contrast-enhanced CT in patients with septic shock. • The HAGS is characterized by the much lower-attenuated central zone of the adrenal gland in arterial phase and it showed excellent reproducibility between different observers. • The HAGS is specific and common on dual-phase contrast-enhanced CT in patients with septic shock and predicts a poor prognosis.

Lifetime glucocorticoid profiles in baleen of right whale calves: potential relationships to chronic stress of repeated wounding by Kelp Gulls

Baleen tissue accumulates stress hormones (glucocorticoids, GC) as it grows, along with other adrenal, gonadal and thyroid hormones. The hormones are deposited in a linear fashion such that a single plate of baleen allows retrospective assessment and evaluation of long-term trends in the whales' physiological condition. In whale calves, a single piece of baleen contains hormones deposited across the lifespan of the animal, with the tip of the baleen representing prenatally grown baleen. This suggests that baleen recovered from stranded carcasses of whale calves could be used to examine lifetime patterns of stress physiology. Here we report lifetime profiles of cortisol and corticosterone in baleen of a North Atlantic right whale ('NARW'-Eubalaena glacialis) calf that died from a vessel strike, as well as four southern right whale ('SRW'-Eubalaena australis) calves that were found dead with varying severity of chronic wounding from Kelp Gull (Larus dominicanus) attacks. In all five calves, prenatally grown baleen exhibited a distinctive profile of elevated glucocorticoids that declined shortly before birth, similar to GC profiles reported from baleen of pregnant females. After birth, GC profiles in calf baleen corresponded with the degree of wounding. The NARW calf and two SRW calves with no or few gull wounds had relatively low and constant GC content throughout life, while two SRW calves with high numbers of gull wounds had pronounced elevations in baleen GC content in postnatal baleen followed by a precipitous decline shortly before death, a profile suggestive of prolonged chronic stress. Baleen samples may present a promising and valuable tool for defining the baseline physiology of whale calves and may prove useful for addressing conservation-relevant questions such as distinguishing acute from chronic stress and, potentially, determining cause of death.

Pediatric Multiple Organ Dysfunction Syndrome: Promising Therapies

OBJECTIVE

To describe the state of the science, identify knowledge gaps, and offer potential future research questions regarding promising therapies for children with multiple organ dysfunction syndrome presented during the Eunice Kennedy Shriver National Institute of Child Health and Human Development Workshop on Pediatric Multiple Organ Dysfunction Syndrome (March 26-27, 2015).

DATA SOURCES

Literature review, research data, and expert opinion.

STUDY SELECTION

Not applicable.

DATA EXTRACTION

Moderated by an expert from the field, issues relevant to the association of multiple organ dysfunction syndrome with a variety of conditions were presented, discussed, and debated with a focus on identifying knowledge gaps and research priorities.

DATA SYNTHESIS

Summary of presentations and discussion supported and supplemented by relevant literature.

CONCLUSIONS

Among critically ill children, multiple organ dysfunction syndrome is relatively common and associated with significant morbidity and mortality. For outcomes to improve, effective therapies aimed at preventing and treating this condition must be discovered and rigorously evaluated. In this article, a number of potential opportunities to enhance current care are highlighted including the need for a better understanding of the pharmacokinetics and pharmacodynamics of medications, the effect of early and optimized nutrition, and the impact of effective glucose control in the setting of multiple organ dysfunction syndrome. Additionally, a handful of the promising therapies either currently being implemented or developed are described. These include extracorporeal therapies, anticytokine therapies, antitoxin treatments, antioxidant approaches, and multiple forms of exogenous steroids. For the field to advance, promising therapies and other therapies must be assessed in rigorous manner and implemented accordingly.

Heating and ultraviolet light activate anti-stress gene functions in humans

Different environmental factors (i.e., toxins, heavy metals, ultraviolet (UV) rays, and X-radiation) cause damage to DNA, cell membranes and other organelles and induce oxidative stress, which results in the excessive production of reactive oxygen species (ROS) by phagocytes. All types of cell stress are accompanied by the activation of anti-stress genes that can suppress ROS synthesis. We hypothesized that different environmental factors would affect organisms through the activation of anti-stress genes by autologous serum (AS) proteins, followed by the synthesis of molecules that increase cell resistance to oxidative stress. The goal of this work was to study the influence of AS on ROS production by peripheral blood neutrophils isolated from donors in different age groups. Neutrophils were isolated from 59 donors (38-94 years old). AS was heated at 100°C for 30 s. or irradiated by UV light at 200-280 nm and 8 W for 10 min. Neutrophils were exposed to heat shock at 42°C for 1 min. (short-term heating stress) or 43°C for 10 min., followed by the determination of the chemiluminescence reaction induced by zymosan. AS can increase or decrease ROS production by neutrophils depending on the structure of the proteins in the serum; these structures can be changed by heating or UV treatment and the temperature of their interaction (4 or 37°C). We propose that the effect of environmental factors on AS proteins can cause an adverse increase in oxidative stress levels due to the functional reduction of anti-stress genes. We found a negative correlation between the quantity of intracellular Hsp70 and levels of intracellular ROS production following 10 min of heat shock at 43°C. Short-term heating stress (1 min) at 42°C was followed by a prominent reduction in ROS production. This effect may be a result of the impact of the hormone adrenaline on the functions of anti-stress genes. Indeed, the same effect was observed after treatment of the neutrophils with adrenaline at concentrations of 10(-4) and 10(-5) M. In contrast, dexamethasone from the other stress hormone group did not evoke the same effect at the same concentrations.

The role of adrenal gland microenvironment in the HPA axis function and dysfunction during sepsis

Sepsis and septic shock in response to bacterial or viral infections remain the major health problem worldwide. Despite decades of intensive research and improvements in medical care, severe sepsis is associated with high mortality. Rapid activation of the adrenal gland glucocorticoid and catecholamine production is a fundamental component of the stress response and is essential for survival of the host. However, in many critically ill patients this homeostatic function of the adrenal gland is often impaired. In these patients, plasma levels of adrenocorticotropic hormone (ACTH) and cortisol are often dissociated. This has been attributed to the stimulatory action of non-ACTH factors within the adrenal gland such as cytokines, and recently with decreased cortisol metabolism and suppressed ACTH synthesis. Regulation of the hypothalamus-pituitary-adrenal (HPA) axis function during sepsis is a complex process which involves various immune and neuroendocrine interactions occurring at the levels of the central nervous system (CNS) and the adrenal gland. A coordinated interaction of numerous cell types and systems within the adrenal gland is involved in the sustained adrenal glucocorticoid production. This review article describes and discusses recent experimental findings regarding the role of adrenal gland microenvironment including the adrenal vasculature and the immune-adrenal crosstalk in the disregulated HPA axis during sepsis conditions. In summary, in addition to the reduced cortisol breakdown and related ACTH suppression, sepsis-mediated chronic activation of the immune-adrenal crosstalk and vascular dysfunction may contribute to the HPA axis dysregulation found in septic patients.

High prevalence of primary adrenal insufficiency in Zellweger spectrum disorders

Zellweger spectrum disorders are a group of autosomal recessive disorders characterized by impaired peroxisome functions. The clinical spectrum is broad, ranging from the classical most severe Zellweger syndrome to patients with a relatively mild phenotype. Treatment options are limited to symptomatic and supportive therapy. During routine follow-up we discovered patients with asymptomatic primary adrenal insufficiency. It is important to detect impaired adrenal function because it has treatment implications. Primary adrenal insufficiency was found in 7/24 patients examined, with 4/7 being asymptomatic. Systematic evaluation of adrenal function, through a Synacthen test, should be included in the clinical management of these patients.

A preliminary investigation into adrenal responsiveness and outcomes in patients with cardiogenic shock after acute myocardial infarction

PURPOSE

This study investigated the significance of baseline cortisol levels and adrenal response to corticotropin in shocked patients after acute myocardial infarction (AMI).

METHODS

A short corticotropin stimulation test was performed in 35 patients with cardiogenic shock after AMI by intravenously injecting of 250 μg of tetracosactrin (Synacthen). Blood samples were obtained at baseline (T0) before and at 30 (T30) and 60 (T60) minutes after the test to determine plasma total cortisol (TC) and free cortisol concentrations. The main outcome measure was in-hospital mortality and its association with T0 TC and maximum response to corticotropin (maximum difference [Δ max] in cortisol levels between T0 and the highest value between T30 and T60).

RESULTS

The in-hospital mortality was 37%, and the median time to death was 4 days (interquartile range, 3-9 days). There was some evidence of an increased mortality in patients with T0 TC concentrations greater than 34 μg/dL (P=.07). Maximum difference by itself was not an independent predictor of death. Patients with a T0 TC 34 μg/dL or less and Δ max greater than 9 μg/dL appeared to have the most favorable survival (91%) when compared with the other 2 groups: T0 34 μg/dL or less and Δ max 9 μg/dL or less or T0 34 μg/dL or higher and Δ max greater than 9 μg/dL (75%; P=.8) and T0 greater than 34 μg/dL and Δ max 9 μg/dL or less (60%; P=.02). Corticosteroid therapy was associated with an increased mortality (P=.03). There was a strong correlation between plasma TC and free cortisol (r=0.85).

CONCLUSIONS

A high baseline plasma TC was associated with a trend toward increased mortality in patients with cardiogenic shock post-AMI. Patients with lower baseline TC, but with an inducible adrenal response, appeared to have a survival benefit. A prognostic system based on basal TC and Δ max similar to that described in septic shock appears feasible in this cohort. Corticosteroid therapy was associated with adverse outcomes. These findings require further validation in larger studies.

High-dose glucocorticoid aggravates TBI-associated corticosteroid insufficiency by inducing hypothalamic neuronal apoptosis

Emerging experimental and clinical data suggest that severe illness, such as traumatic brain injury (TBI), can induce critical illness-related corticosteroid insufficiency (CIRCI). However, underlying mechanisms of this TBI-associated CIRCI remain poorly understood. We hypothesized that dexamethasone (DXM), a synthetic glucocorticoid, which was widely used to treat TBI, induces hypothalamic neuronal apoptosis to aggravate CIRCI. To test this hypothesis, we have evaluated the dose effect of DXM (1 or 10mg/kg) on the development of acute CIRCI in rats with fluid percussion injury-induced TBI and on cultured rat hypothalamic neurons in vitro (DXM, 10(-5)-10(-8)mol/L). Corticosterone Increase Index was recorded as the marker for CIRCI. In addition, MTT and TUNEL assays were used to measure the viability and apoptosis of hypothalamic neurons in primary culture. Moreover, high-resolution hopping probe ion conductance microscopy (HPICM) was used to monitor the DXM-induced morphological changes in neurons. The incidence of acute CIRCI was significantly higher in the high-dose DXM group on post-injury day 7. Cellular viability was significantly decreased from 12h to 24h after the treatment with a high-dose of DXM. A significantly increase in TUNEL positive cells were detected in cultured cells treated with a high-dose of DXM after 18h. Neurites of hypothalamic neuron were dramatically thinner and the numbers of dendritic beadings increased in neurons treated with the high dose of DXM for 12h. In conclusion, high-dose DXM induced hypothalamic neurons to undergo apoptosis in vivo and in vitro, which may aggravate TBI-associated CIRCI.

Update on adrenal insufficiency in patients with liver cirrhosis

Liver cirrhosis is a major cause of mortality worldwide, often with severe sepsis as the terminal event. Over the last two decades, several studies have reported that in septic patients the adrenal glands respond inappropriately to stimulation, and that the treatment with corticosteroids decreases mortality in such patients. Both cirrhosis and septic shock share many hemodynamic abnormalities such as hyperdynamic circulatory failure, decreased peripheral vascular resistance, increased cardiac output, hypo-responsiveness to vasopressors, increased levels of proinflammatory cytokines [interleukine(IL)-1, IL-6, tumor necrosis factor-alpha] and it has, consequently, been reported that adrenal insufficiency (AI) is common in critically ill cirrhotic patients. AI may also be present in patients with stable cirrhosis without sepsis and in those undergoing liver transplantation. The term hepato-adrenal syndrome defines AI in patients with advanced liver disease with sepsis and/or other complications, and it suggests that it could be a feature of liver disease per se, with a different pathogenesis from that of septic shock. Relative AI is the term given to inadequate cortisol response to stress. More recently, another term is used, namely "critical illness related corticosteroid insufficiency" to define "an inadequate cellular corticosteroid activity for the severity of the patient's illness". The mechanisms of AI in liver cirrhosis are not completely understood, although decreased levels of high-density lipoprotein cholesterol and high levels of proinflammatory cytokines and circulatory endotoxin have been suggested. The prevalence of AI in cirrhotic patients varies widely according to the stage of the liver disease (compensated or decompensated, with or without sepsis), the diagnostic criteria defining AI and the methodology used. The effects of corticosteroid therapy on cirrhotic patients with septic shock and AI are controversial. This review aims to summarize the existing published information regarding AI in patients with liver cirrhosis.

Mineralocorticoid deficiency in hemorrhagic shock

BACKGROUND

In the critically ill, mineralocorticoid deficiency (MD) is associated with greater disease severity, the development of acute renal insufficiency, and increased mortality. We hypothesized that severely injured trauma patients presenting with hemorrhagic shock would demonstrate a high degree of MD. We also hypothesized that MD in these patients would be associated with increased length of stay, hypotension, fluid requirements, and acute kidney injury (AKI).

MATERIALS AND METHODS

Thirty-two trauma patients in hemorrhagic shock on admission to the trauma bay (SBP <90 mm Hg × 2) were enrolled. Blood samples were obtained on ICU admission and 8, 16, 24, and 48 hours later. Plasma aldosterone (PA) and renin (PR) were assayed by radioimmunoassay. MD was defined as a ratio of PA/PR ≤2. Demographic data, injury severity score, ICU and hospital length of stay, fluid requirements, mean arterial pressure, serum sodium, hypotension, and risk for AKI were compared for patients with and without MD.

RESULTS

At ICU admission, 48% of patients met criteria for MD. Patients with MD were significantly more likely to experience hypotension (MAP ≤60 mm Hg) during the study period. MD patients required significantly more units of blood in 48 h than non-MD patients (13 [7-22] versus 5 [2-7], P = 0.015) and had increased crystalloid requirements (18L [14-23] versus 9L [6-10], P < 0.001). MD patients were at higher risk for AKI according to RIFLE and AKIN criteria.

CONCLUSIONS

MD is a common entity in trauma patients presenting in hemorrhagic shock. Patients with MD required a more aggressive resuscitative effort, were more likely to experience hypotension, and had a higher risk of AKI than non-MD patients. Future studies are needed to fully understand the impact of MD following trauma and the potential role for hormonal replacement therapy.

Association of adrenocorticotrophin and cortisol concentrations with peripheral blood leukocyte cytokine gene expression in septic and nonseptic neonatal foals

BACKGROUND

The hypothalamic-pituitary-adrenal (HPA) is influenced by the proinflammatory cytokines IL-6, IL-1β, and TNF-α in critically ill humans. Information about the association of cytokines with the HPA axis in neonatal foals is lacking.

HYPOTHESIS/OBJECTIVES

The objectives were to describe for hospitalized septic and nonseptic foals (1) temporal changes in blood concentrations of ACTH, and cortisol, and leukocyte cytokine gene expression, and (2) coassociation of these HPA axis hormones with blood leukocyte cytokine gene expression.

ANIMALS

Hospitalized septic foals (N = 15) and hospitalized nonseptic foals (N = 11).

METHODS

Blood samples, obtained from study foals at admission (T = 0), and 24 (T = 1), 48 (T = 2), 72 (T = 3), and 96 (T = 4) hours after admission, were processed to isolate RNA from leukocytes and to harvest plasma and serum for hormone assays. Plasma ACTH and serum cortisol concentrations were determined by radioimmunoassay. Leukocyte mRNA expression of IL-1β IL-6, IL-8, IL-10, and TNF-α was determined using RT-PCR.

RESULTS

Cortisol concentrations were greater (P < .05) in foals at admission than at other time points. The expressions of IL-8 and IL-10 mRNA were lower (P < .05) at each time point in septic than in nonseptic foals. Among septic foals, ACTH was positively associated (P = .0026) with IL-6 mRNA expression.

CONCLUSIONS

Sepsis influences secretion of the HPA axis hormones and expression of cytokines in foals. A positive association with the HPA axis and IL-6 expression was detected. The clinical importance of these findings requires additional study.

Effects of low-dose hydrocortisone therapy on immune function in neonatal horses

Low-dose hydrocortisone (LDHC) therapy modulates inflammatory responses in adults and improves outcomes in some septic adults and neonates, but its immunologic effects have not been evaluated in neonates. The objective of this study was to evaluate effects of LDHC therapy on ex vivo immune function in neonatal horses (foals). We hypothesized that LDHC treatment would dampen proinflammatory responses without impairing neutrophil function. Hydrocortisone (1.3 mg/kg/d i.v.) was administered to foals in a tapering 3.5 d course. Peripheral blood leukocytes were collected from foals before, during, and after hydrocortisone treatment. A separate group of age-matched untreated foals served as controls. Endotoxin-induced peripheral blood mononuclear cell gene expression of inflammatory cytokines was measured by real-time quantitative RT-PCR. Neutrophils were incubated with labeled, killed Staphylococcus aureus or Escherichia coli for assessment of phagocytosis, and with phorbol myristate acetate, zymosan, or endotoxin for measurement of reactive oxygen species (ROS) production. Neutrophil phagocytosis and ROS production were similar in both groups. Foals receiving hydrocortisone had significantly decreased endotoxin-induced expression of TNF-α, IL-6, IL-8, and IL-1β. These data suggest that this LDHC treatment regimen ameliorates endotoxin-induced proinflammatory cytokine expression in neonatal foals without impairing innate immune responses needed to combat bacterial infection.

Adrenocortical insufficiency in horses and foals

The adrenal cortices produce various steroid hormones that play vital roles in several physiologic processes. Although permanent adrenocortical insufficiency is rare in all species, emerging evidence in both human and equine medicine suggests that transient reversible adrenocortical dysfunction resulting in cortisol insufficiency frequently develops during critical illness. This syndrome is termed relative adrenal insufficiency (RAI) or critical illness-related corticosteroid insufficiency (CIRCI) and can contribute substantially to morbidity and mortality associated with the primary disease. This review discusses the mechanisms, diagnosis, and clinical consequences of adrenocortical insufficiency, with particular focus on the current understanding of RAI/CIRCI in horses and foals.

Risk factors and outcome of changes in adrenal response to ACTH in the course of critical illness

BACKGROUND

To evaluate the concept of critical illness-related corticosteroid insufficiency (CIRCI) by studying the clinical significance, in terms of risk factors and outcome, of changes in the cortisol response to repeated adrenocorticotropic hormone (ACTH) testing in the course of critical illness.

PATIENTS AND METHODS

In a retrospective study in a medical-surgical intensive care unit (ICU) of a university hospital, we retrospectively included 54 consecutive patients during a 3-year period, who underwent 2 conventional 250 μg ACTH tests at an interval >24 hours, because of ≥6 hours hypotension requiring repeated fluid challenges or vasopressor/inotropic treatment, while corticosteroid treatment was not (yet) initiated. Serum cortisol was measured immediately before and 30 and 60 minutes after intravenous injection of 250 μg of ACTH. Patients were divided into those with an increase (≥0, n = 27) or a decrease (n = 27) in time in delta (Δ) cortisol in response to ACTH and with a Δcortisol <100 (n = 11) and ≥100 nmol/L (n = 43) at the second ACTH test.

RESULTS

Changes in Δcortisol in time were paralleled by changes in Δcortisol/albumin, with a higher frequency of septic shock, persistently high disease severity, increased renal replacement therapy, and decreased platelet counts in the course of disease with a decrease in Δcortisol in time. Similar trends in increased disease severity were observed when Δcortisol remained or fell to <100 nmol/L. A decrease in Δcortisol between the 2 tests, particularly to <100 nmol/L, was associated with increased mortality (18 nonsurvivors in the ICU).

CONCLUSIONS

The findings favor the concept of dynamic adrenal function rather than poor reproducibility of the ACTH test, so that development of CIRCI, particularly in complicated septic shock and indicated by a fall in Δcortisol (to <100 nmol/L) upon ACTH, correlates to a poor prognosis, independently of baseline cortisol, cortisol binding in blood, and disease severity.

Assessment of the hypothalamic-pituitary-adrenal axis in critical illness

Cortisol is the main corticosteroid secreted from the human adrenal cortex, and it has a crucial role for survival in stressful conditions. An adequate increase in levels of cortisol helps patients to cope with the severity of the disease in the acute phase of critical illness. Either higher or lower than expected cortisol levels were found to be related to increased mortality. Prolonged activation of the hypothalamic-pituitary-adrenal (HPA) axis can result in hypercortisolemia or hypocortisolemia; both can be detrimental to recovery from critical illness. Primary and secondary adrenal insufficiency, relative adrenal insufficiency, tissue resistance to glucocorticoids, adrenocorticotrophic hormone deficiency and immune-mediated inhibition of the HPA axis can be the cause of the impairment of the secretion or action of cortisol in critically ill patients. Recently, some authors offered the term 'critical illness-related corticosteroid insufficiency' to better point out the relative adrenal insufficiency that is seen during critical illness. Patients with critical illness-related corticosteroid insufficiency not only have insufficient circulating cortisol but also have impaired cellular utilization of cortisol. In this article, how adrenal dysfunction presents in critical illness and how appropriate diagnosis and management can be achieved in the critical care setting will be discussed.

Serum cytokines and critical illness-related corticosteroid insufficiency

PURPOSE

Little information exists regarding the association of specific cytokine levels and different subgroups of patients with critical illness-related corticosteroid insufficiency (CIRCI).

METHODS

Data from a previous prospective study on adrenal function in the ICU were used in this study. CIRCI was diagnosed when either the basal cortisol was less than 10 μg/ml or the Δ cortisol was less than 9 μg/ml. The patients with CIRCI were further divided into a low basal cortisol (LBC) group (basal cortisol < 10 μg/ml), and low Δ cortisol (LDC) group (basal cortisol ≥ 10 μg/ml and Δ cortisol < 9 μg/ml). Serum cytokine levels were compared among the normal (NOM), LBC, and LDC groups.

RESULTS

The serum of 82 out of 123 (67%) patients included in the previous study was available for analysis; these patients were included in the present study. The overall incidence of CIRCI was 43.9% (36 out of 82 patients). Among patients with CIRCI, 16 (44.4%) were classified as the LBC group and 20 (55.6%) as the LDC group. The LDC group had significantly higher levels of IL-6 and IL-10 compared to both the NOM and LBC groups (p < 0.01). The LDC group also had significantly increased TNF-α (p = 0.002) compared to the LBC group. There were no significant differences in any of the cytokine levels between the NOM and LBC groups.

CONCLUSIONS

Elevated cytokines were associated with adrenal dysfunction in a subset of patients meeting the criteria for CIRCI (normal or high basal cortisol and low Δ cortisol).

Decreased cytosolic glucocorticoid receptor levels in critically ill patients

The immune system and the hypothalamic-pituitary-adrenal axis are linked by several mechanisms. Intracellular glucocorticoid receptors represent one important connection. The aim of this study was to examine the coherence between the number of glucocorticoid receptors, activation of the hypothalamic-pituitary-adrenal axis, inflammatory cytokine levels and the severity of illness in critically ill patients. In a prospective study, blood was collected from 20 healthy members of the hospital staff (control group) and 50 ventilated patients (sample group) within the first 24 hours after intubation and within three days of extubation. 3H-dexamethasone-binding assay was used to assess cytoplasmatic free glucocorticoid receptors levels. ACTH, cortisol, IL-6 and TNFa levels were measured by ELISA. In the sample group, specific binding of 3H-dexamethasone was significantly decreased compared to the control group. Glucocorticoid receptor levels tended to be lower in more severely ill patients. Plasma cortisol and ACTH levels were significantly different from the control group after extubation but not at intubation. Severe illness is associated with rapid down-regulation of 3H-dexamethasone binding. This decrease occurs before elevation of plasma cortisol. Therefore, down-regulation of cortisol binding may be directly associated with the stress response and not due to feedback regulation following increase in plasma cortisol levels.

Critical illness-related corticosteroid insufficiency in a dog with septic shock

OBJECTIVE

To describe a case of hydrocortisone-responsive hypotension and critical illness-related corticosteroid insufficiency (CIRCI) in a dog with septic shock.

CASE SUMMARY

A dog with aspiration pneumonia developed septic shock with pressor-refractory hypotension. A standard ACTH stimulation test was performed that showed a blunted cortisol response consistent with CIRCI. Reversal of shock was achieved within 2 hours of hydrocortisone administration, and complete weaning from pressors was accomplished over the subsequent 8 hours. The patient recovered and was discharged from the hospital. An ACTH stimulation test performed 1 month after hospital discharge showed normal adrenal responsiveness consistent with resolution of CIRCI.

NEW OR UNIQUE INFORMATION PROVIDED

This case is the first published report of hydrocortisone-responsive hypotension and transient CIRCI associated with naturally occurring septic shock in a dog.

A prospective study on the incidence and predictive factors of relative adrenal insufficiency in Korean critically-ill patients

This study was undertaken to evaluate the incidence and risk factors associated with relative adrenal insufficiency (RAI) in Korean critically-ill patients. All patients who were admitted to the Medical Intensive Care Unit (MICU) of Samsung Medical Center between January 1, 2006 and April 30, 2007 were prospectively evaluated using a short corticotropin stimulation test on the day of admission. RAI was defined as an increase in the serum cortisol level of <9 microg/dL from the baseline after administration of 250 microg of corticotropin. In all, 123 patients were recruited and overall the incidence of RAI was 44% (54/123). The presence of septic shock (P=0.001), the Simplified Acute Physiology Score (SAPS) II (P=0.003), the Sequential Organ Failure Assessment (SOFA) score (P=0.001), the mean heart rate (P=0.040), lactate levels (P=0.001), arterial pH (P=0.047), treatment with vasopressors at ICU admission (P=0.004), and the 28-day mortality (P=0.041) were significantly different between patients with and without RAI. The multivariate analysis showed that the SOFA score was an independent predictor of RAI in critically-ill patients (odd ratio=1.235, P=0.032). Our data suggest that RAI is frequently found in Korean critically-ill patients and that a high SOFA score is an independent predictor of RAI in these patients.

The altered adrenal axis and treatment with glucocorticoids during critical illness

Critical illness is generally hallmarked by activation of the hypothalamic-pituitary-adrenal axis. The development of very high levels of cortisol has been associated with severe illness and a raised risk of death. Likewise, a response that is inadequate relative to the degree of stress, termed relative adrenal insufficiency (also known as critical-illness-related corticosteroid insufficiency) has been associated with increased mortality. Much controversy exists with regard to the definition and biochemical testing of an adequate adrenal response to critical illness, which hampers diagnosis. High doses of glucocorticoids have been shown to have no effect in this setting and might be harmful. Moderate doses have been advocated, however, for critically ill patients with inflammatory conditions, such as acute respiratory distress syndrome and septic shock syndrome. Initial results from proof-of-concept studies were promising but thus far have not been reproduced in large, multicenter trials, although the latter were underpowered to yield definite conclusions. The role of glucocorticoid therapy in intensive care, therefore, remains uncertain. Until the debate has been settled, we recommend that use of glucocorticoid therapy in critically ill patients should continue to be based on the clinician's judgment and that routine adjuvant use should be avoided.