Corticosteroids for treating severe sepsis and septic shock

Corticosteroids for treating sepsis in children and adults

BACKGROUND

Sepsis occurs when an infection is complicated by organ failure. Sepsis may be complicated by impaired corticosteroid metabolism. Thus, providing corticosteroids may benefit patients. The original review was published in 2004 and was updated in 2010 and 2015 prior to this update.

OBJECTIVES

To examine the effects of corticosteroids on death in children and adults with sepsis.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, LILACS, ClinicalTrials.gov, ISRCTN, and the WHO Clinical Trials Search Portal, on 25 July 2019. In addition, we conducted reference checking and citation searching, and contacted study authors, to identify additional studies as needed.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) of corticosteroids versus placebo or usual care (antimicrobials, fluid replacement, and vasopressor therapy as needed) in children and adults with sepsis. We also included RCTs of continuous infusion versus intermittent bolus of corticosteroids.

DATA COLLECTION AND ANALYSIS

All review authors screened and selected studies for inclusion. One review author extracted data, which was checked by the others, and by the lead author of the primary study when possible. We obtained unpublished data from the authors of some trials. We assessed the methodological quality of trials and applied GRADE to assess the certainty of evidence. Review authors did not contribute to assessment of eligibility and risk of bias, nor to data extraction, for trials they had participated in.

MAIN RESULTS

We included 61 trials (12,192 participants), of which six included only children, two included children and adults, and the remaining trials included only adults. Nine studies are ongoing and will be considered in future versions of this review. We judged 19 trials as being at low risk of bias. Corticosteroids versus placebo or usual care Compared to placebo or usual care, corticosteroids probably slightly reduce 28-day mortality (risk ratio (RR) 0.91, 95% confidence interval (CI) 0.84 to 0.99; 11,233 participants; 50 studies; moderate-certainty evidence). Corticosteroids may result in little to no difference in long-term mortality (RR 0.97, 95% CI 0.91 to 1.03; 6236 participants; 7 studies; low-certainty evidence) and probably slightly reduce hospital mortality (RR 0.90, 95% CI 0.82 to 0.99; 8183 participants; 26 trials; moderate-certainty evidence). Corticosteroids reduced length of intensive care unit (ICU) stay for all participants (mean difference (MD) -1.07 days, 95% CI -1.95 to -0.19; 7612 participants; 21 studies; high-certainty evidence) and resulted in a large reduction in length of hospital stay for all participants (MD -1.63 days, 95% CI -2.93 to -0.33; 8795 participants; 22 studies; high-certainty evidence). Corticosteroids increase the risk of muscle weakness (RR 1.21, 95% CI 1.01 to 1.44; 6145 participants; 6 studies; high-certainty evidence). Corticosteroids probably do not increase the risk of superinfection (RR 1.06, 95% CI 0.95 to 1.19; 5356 participants; 25 studies; moderate-certainty evidence). Corticosteroids increase the risk of hypernatraemia (high-certainty evidence) and probably increase the risk of hyperglycaemia (moderate-certainty evidence). Moderate-certainty evidence shows that there is probably little or no difference in gastroduodenal bleeding, stroke, or cardiac events, and low-certainty evidence suggests that corticosteroids may result in little to no difference in neuropsychiatric events. Continuous infusion of corticosteroids versus intermittent bolus We are uncertain about the effects of continuous infusion of corticosteroids compared with intermittent bolus administration. Three studies reported data for this comparison, and the certainty of evidence for all outcomes was very low.

AUTHORS' CONCLUSIONS

Moderate-certainty evidence indicates that corticosteroids probably reduce 28-day and hospital mortality among patients with sepsis. Corticosteroids result in large reductions in ICU and hospital length of stay (high-certainty evidence). There may be little or no difference in the risk of major complications; however, corticosteroids increase the risk of muscle weakness and hypernatraemia, and probably increase the risk of hyperglycaemia. The effects of continuous versus intermittent bolus administration of corticosteroids are uncertain.

Impact and Beneficial Critical Points of Clinical Outcome in Corticosteroid Management of Adult Patients With Sepsis: Meta-Analysis and GRADE Assessment

Background: With new randomised pieces of evidence and the latest clinical practice guideline from the BMJ emerging in 2018, an updated analysis of best available evidence on the controversial effects of corticosteroids in sepsis is warranted. Objectives: To comprehensively evaluate whether corticosteroids are beneficial in reducing mortality and what cumulative dosage, daily dosage, and duration of corticosteroid treatment would enable adult patients with sepsis to reach the critical point of benefits. Methods: Ovid MEDLINE, Ovid EMbase, Cochrane Library, and LILACS database were searched until March 22, 2019. Results: Thirty RCTs with 8,836 participants were identified. Long course low-dose corticosteroid therapy could improve 28-day mortality (RR = 0.90, 95% CI = 0.84-0.97; high quality), intensive care unit mortality (RR = 0.87; 95% CI = 0.79-0.95; moderate quality), and in-hospital mortality (RR = 0.88, 95% CI = 0.79-0.997; high quality). However, we found no benefits for 90-day, 180-day, and 1-year mortality. Subgroup results of long course corticosteroid treatment in a population with septic shock and vasopressor-dependent septic shock, corticosteroid regimen with hydrocortisone plus fludrocortisone, corticosteroid dosing strategies including bolus dosing and infusion dosing, the strategies of abrupt discontinuation, timing of randomisation ≤24 h, impact factor of ≥10, and sample size ≥500 were associated with a marginally reduction in 28-day mortality. Conclusions: This meta-analysis found that the long course low-dose and not short course high-dose corticosteroid treatment could marginally improve short-term 28-day mortality with high quality, especially septic shock and vasopressor-dependent septic shock, and it is recommended that long course (about 7 days) low-dose (about 200-300mg per day) hydrocortisone (or equivalent) with cumulative dose (at least about 1,000mg) may be a viable management option for overall patients with sepsis, and it can be also adapted to patient with septic shock alone. Early hydrocortisone plus fludrocortisone administration, via continuous infusion or bolus dosing, is also particularly important for the prognosis. Abrupt discontinuation of corticosteroids, as opposed to the conventional tapered discontinuation, may be considered as a desirable option in 28-day mortality. The safety profile of long course low-dose corticosteroid treatment, including adverse hyperglycaemia and hypernatraemia events, remains a concern, although these events could be easily treated. Clinical Trial Registration: PROSPERO, identifier CRD 42018092849.

Bloodstream Infections

Bacteremia and sepsis are conditions associated with high mortality and are of great impact to health care operations. Among the top causes of mortality in the United States, these conditions cause over 600 fatalities each day. Empiric, broad-spectrum treatment is a common but often a costly approach that may fail to effectively target the correct microbe, may inadvertently harm patients via antimicrobial toxicity or downstream antimicrobial resistance. To meet the diagnostic challenges of bacteremia and sepsis, laboratories must understand the complexity of diagnosing and treating septic patients, in order to focus on creating algorithms that can help direct a more targeted approach to antimicrobial therapy and synergize with existing clinical practices defined in new Surviving Sepsis Guidelines. Significant advances have been made in improving blood culture media; as yet no molecular or antigen-based method has proven superior for the detection of bacteremia in terms of limit of detection. Several methods for rapid molecular identification of pathogens from blood cultures bottles are available and many more are on the diagnostic horizon. Ultimately, early intervention by molecular detection of bacteria and fungi directly from whole blood could provide the most patient benefit and contribute to tailored antibiotic coverage of the patient early on in the course of the disease. Although blood cultures remain as the best means of diagnosing bacteremia and candidemia, complementary testing with antigen tests, microbiologic investigations from other body sites, and histopathology can often aid in the diagnosis of disseminated disease, and application of emerging nucleic acid test methods and other new technology may greatly impact our ability to bacteremic and septic patients, particularly those who are immunocompromised.

High-volume haemofiltration for sepsis in adults

BACKGROUND

Severe sepsis and septic shock are leading causes of death in the intensive care unit (ICU), despite advances in the treatment of patients with severe sepsis and septic shock, including early recognition, appropriate treatment with antibiotics and support of organs that may have been affected by the illness. High-volume haemofiltration (HVHF) is a blood purification technique that may improve outcomes in severe sepsis or septic shock. The technique of HVHF has evolved from renal replacement therapies used in the ICU to treat critically ill patients with acute kidney injury (AKI). This review was first published in 2013 and was updated in 2016.

OBJECTIVES

To investigate whether HVHF improves outcomes in critically ill adults admitted to the intensive care unit with severe sepsis or septic shock. The primary outcome of this systematic review is patient mortality; secondary outcomes include duration of stay, severity of organ dysfunction and adverse events.

SEARCH METHODS

For this updated version, we extended searches of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Latin American Caribbean Health Sciences Literature (LILACS), Web of Science and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) to 31 December 2015. The original search was performed in 2011. We also searched trials registers.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and quasi-randomized trials comparing HVHF or high-volume haemodiafiltration versus standard or usual dialysis therapy, as well as RCTs and quasi-randomized trials comparing HVHF or high-volume haemodiafiltration versus no similar dialysis therapy. These studies involved adults treated in critical care units.

DATA COLLECTION AND ANALYSIS

Three review authors independently extracted data and assessed trial quality. We sought additional information from trialists as required.

MAIN RESULTS

We included four randomized trials involving 200 participants. Owing to small numbers of studies and participants, it was not possible to combine data for all outcomes. Two trials reported 28-day mortality, and one trial reported hospital mortality; in the third trial, the number of deaths stated did not match the quoted mortality rates. The pooled risk ratio (95% confidence interval) for 28-day mortality associated with HVHF was 0.89 (0.60 to 1.32, two trials, 146 participants, low-quality evidence). One study (137 participants, low-quality evidence) reported length of stay in the ICU. Two trials (170 participants, low-quality evidence) reported organ dysfunction, but we could not pool results owing to reporting differences. Three studies (189 participants, low-quality evidence) reported on haemodynamic changes, but we could not pool results owing to reporting differences. Investigators reported no adverse events. Overall, the included studies had low risk of bias.

AUTHORS' CONCLUSIONS

Investigators reported no adverse effects of HVHF (low-quality evidence). The results of this meta-analysis show that very few studies have been conducted to investigate the use of HVHF in critically ill patients with severe sepsis or septic shock (four studies, 201 participants, low-quality evidence). Researchers should consider additional randomized controlled trials that are large and multi-centred and have clinically relevant outcome measures. The cost-effectiveness of HVHF should also be studied. .

Should all adjunctive corticosteroid therapy be avoided in the management of hemodynamically stabile Staphylococcus aureus bacteremia?

The purpose of this study was to examine the prognostic impact of corticosteroids in hemodynamically stabile Staphylococcus aureus bacteremia (SAB). There were 361 hemodynamically stabile methicillin-sensitive SAB patients with prospective follow-up and grouping according to time-point, dose and indication for corticosteroid therapy. To enable analyses without external interfering corticosteroid therapy all patients with corticosteroid therapy equivalent to prednisone >10 mg/day for ≥1 month prior to positive blood culture results were excluded. Twenty-five percent (92) of patients received corticosteroid therapy of which 11 % (40) had therapy initiated within 1 week (early initiation) and 9 % (31) had therapy initiated 2-4 weeks after (delayed initiation) positive blood culture. Twenty-one patients (6 %) had corticosteroid initiated after 4 weeks and were not included in the analyses. A total of 55 % (51/92) received a weekly prednisone dose >100 mg. Patients with early initiated corticosteroid therapy had higher mortality compared to patients treated without corticosteroid therapy at 28 days (20 % vs. 7 %) (OR, 3.11; 95%CI, 1.27-7.65; p < 0.05) and at 90 days (30 % vs. 10 %) (OR, 4.01; 95%CI, 1.82-8.81; p < 0.001). Considering all prognostic markers, early initiated corticosteroid therapy predicted 28-day (HR, 3.75; 95%CI, 1.60-8.79; p = 0.002) and 90-day (HR, 3.10; 95%CI, 1.50-6.39; p = 0.002) mortality in Cox proportional hazards regression analysis. When including only patients receiving early initiated corticosteroid therapy with prednisone ≥100 mg/week the negative prognostic impact on 28-day mortality was accentuated (HR 4.8, p = 0.001). Corticosteroid therapy initiation after 1 week of positive blood cultures had no independent prognostic impact. Early initiation of corticosteroid therapy may be associate to increased mortality in hemodynamically stabile SAB.

Corticosteroids for treating sepsis

BACKGROUND

Sepsis occurs when an infection is complicated by organ failures as defined by a sequential organ failure assessment (SOFA) score of two or higher. Sepsis may be complicated by impaired corticosteroid metabolism. Giving corticosteroids may benefit patients. The original review was published in 2004 and was updated in 2010 and again in 2015.

OBJECTIVES

To examine the effects of corticosteroids on death at one month in patients with sepsis, and to examine whether dose and duration of corticosteroids influence patient response to this treatment.

SEARCH METHODS

We searched the Central Register of Controlled Trials (CENTRAL; 2014, Issue 10), MEDLINE (October 2014), EMBASE (October 2014), Latin American Caribbean Health Sciences Literature (LILACS; October 2014) and reference lists of articles, and we contacted trial authors. The original searches were performed in August 2003 and in October 2009.

SELECTION CRITERIA

We included randomized controlled trials of corticosteroids versus placebo or supportive treatment in patients with sepsis.

DATA COLLECTION AND ANALYSIS

All review authors agreed on the eligibility of trials. One review author extracted data, which were checked by the other review authors, and by the primary author of the paper when possible. We obtained some missing data from trial authors. We assessed the methodological quality of trials.

MAIN RESULTS

We identified nine additional studies since the last update, for a total of 33 eligible trials (n = 4268 participants). Twenty-three of these 33 trials were at low risk of selection bias, 22 were at low risk of performance and detection bias, 27 were at low risk of attrition bias and 14 were at low risk of selective reporting.Corticosteroids reduced 28-day mortality (27 trials; n = 3176; risk ratio (RR) 0.87, 95% confidence interval (CI) 0.76 to 1.00; P value = 0.05, random-effects model). The quality of evidence for this outcome was downgraded from high to low for imprecision (upper limit of 95% CI = 1) and for inconsistency (significant heterogeneity across trial results). Heterogeneity was related in part to the dosing strategy. Treatment with a long course of low-dose corticosteroids significantly reduced 28-day mortality (22 trials; RR 0.87, 95% CI 0.78 to 0.97; P value = 0.01, fixed-effect model). The quality of evidence was downgraded from high to moderate for inconsistency (owing to non-significant effects shown by one large trial). Corticosteroids also reduced mortality rate in the intensive care unit (13 trials; RR 0.82, 95% CI 0.68 to 1.00; P value = 0.04, random-effects model) and at the hospital (17 trials; RR 0.85, 95% CI 0.73 to 0.98; P value = 0.03, random-effects model). Quality of the evidence for in-hospital mortality was downgraded from high to moderate for inconsistency and imprecision (upper limit of 95% CI for RR approaching 1). Corticosteroids increased the proportion of shock reversal by day seven (12 trials; RR 1.31, 95% CI 1.14 to 1.51; P value = 0.0001) and by day 28 (seven trials; n = 1013; RR 1.11, 95% CI 1.02 to 1.21; P value = 0.01) and reduced the SOFA score by day seven (eight trials; mean difference (MD) -1.53, 95% CI -2.04 to -1.03; P value < 0.00001, random-effects model) and survivors' length of stay in the intensive care unit (10 trials; MD -2.19, 95% CI -3.93 to -0.46; P value = 0.01, fixed-effect model) without inducing gastroduodenal bleeding (19 trials; RR 1.24, 95% CI 0. 92 to 1.67; P value = 0.15, fixed-effect model), superinfection (19 trials; RR 1.02, 95% CI 0.87 to 1.20; P value = 0.81, fixed-effect model) or neuromuscular weakness (three trials; RR 0.62, 95% CI 0.21 to 1.88; P value = 0.40, fixed-effect model). Corticosteroid increased the risk of hyperglycaemia (13 trials; RR 1.26, 95% CI 1.16 to 1.37; P value < 0.00001, fixed-effect model) and hypernatraemia (three trials; RR 1.64, 95% CI 1.28 to 2.09; P value < 0.0001, fixed-effect model).

AUTHORS' CONCLUSIONS

Overall, low-quality evidence indicates that corticosteroids reduce mortality among patients with sepsis. Moderate-quality evidence suggests that a long course of low-dose corticosteroids reduced 28-day mortality without inducing major complications and led to an increase in metabolic disorders.

Sepsis in the intensive care unit

Sepsis remains a major cause of mortality in intensive care. The past 15 years has seen a more uniform, world-wide approach to the management of sepsis, severe sepsis and septic shock with improved survival. Recognizing the early symptoms and signs of sepsis are key: the confused, hypoxic, hypotensive patient with pyrexia, tachycardia, tachypnoea and leucocytosis. Examination must include search for a source of infection and early drainage or debridement. Next to take appropriate cultures, give fluids and broad-spectrum antibiotics. If the picture does not improve over the next 6 hours step-up the treatment to include urine output monitoring, blood gases for base excess, lactate, haemoglobin and glucose. These will guide the management of vasopressors, insulin, fluids, transfusion and bicarbonate. If the hypotension persists (septic shock) the patient should be moved to intensive care. The most recent recommendations include the withdrawal of starch based colloids, dobutamine in place of dopamine and a higher threshold for the use of steroids. This should be instituted within 24 hours of the start of sepsis. Advanced care includes mechanical ventilation using the ARDSnet protocol. Prevention by screening, stopping cross infection and appropriate use of antibiotics remains the first priority.

Intensive care unit-related generalized neuromuscular weakness due to critical illness polyneuropathy/myopathy in critically ill patients

Thirty to fifty percent of critically ill patients admitted to the intensive care unit suffer from generalized neuromuscular weakness due to critical illness polyneuropathy, critical illness myopathy, or a combination of them, thus prolonging mechanical ventilation and their intensive care unit stay. A distinction between these syndromes and other neuromuscular abnormalities beginning either before or after ICU admission is necessary. These intensive care unit-related diseases are associated with both elevated mortality rates and increased morbidity rates. Generally, over 50 % of patients will completely recover. Most of them recover after 4-12 weeks, but some patients have been reported to keep on suffering from muscle weakness for at least 4 months. Prevention has a key role in the management of critical illness neuromuscular disorders, as no specific therapy has been suggested. Either prevention or aggressive treatment of sepsis can prevent critical illness polyneuropathy and critical illness myopathy. The dose and duration of the administration of neuromuscular blocking drugs should be limited, and their concurrent administration with corticosteroids should be avoided. Intensive insulin therapy has also been proven to reduce their incidence. Finally, early mobilization via active exercise or electrical muscle stimulation plays a significant role in their prevention.

Corticosteroid treatment for community-acquired pneumonia--the STEP trial: study protocol for a randomized controlled trial

BACKGROUND

Community-acquired pneumonia (CAP) is the third-leading infectious cause of death worldwide. The standard treatment of CAP has not changed for the past fifty years and its mortality and morbidity remain high despite adequate antimicrobial treatment. Systemic corticosteroids have anti-inflammatory effects and are therefore discussed as adjunct treatment for CAP. Available studies show controversial results, and the question about benefits and harms of adjunct corticosteroid therapy has not been conclusively resolved, particularly in the non-critical care setting.

METHODS/DESIGN

This randomized multicenter study compares a treatment with 7 days of prednisone 50 mg with placebo in adult patients hospitalized with CAP independent of severity. Patients are screened and enrolled within the first 36 hours of presentation after written informed consent is obtained. The primary endpoint will be time to clinical stability, which is assessed every 12 hours during hospitalization. Secondary endpoints will be, among others, all-cause mortality within 30 and 180 days, ICU stay, duration of antibiotic treatment, disease activity scores, side effects and complications, value of adrenal function testing and prognostic hormonal and inflammatory biomarkers to predict outcome and treatment response to corticosteroids. Eight hundred included patients will provide an 85% power for the intention-to-treat analysis of the primary endpoint.

DISCUSSION

This largest to date double-blind placebo-controlled multicenter trial investigates the effect of adjunct glucocorticoids in 800 patients with CAP requiring hospitalization. It aims to give conclusive answers about benefits and risks of corticosteroid treatment in CAP. The inclusion of less severe CAP patients will be expected to lead to a relatively low mortality rate and survival benefit might not be shown. However, our study has adequate power for the clinically relevant endpoint of clinical stability. Due to discontinuing glucocorticoids without tapering after seven days, we limit duration of glucocorticoid exposition, which may reduce possible side effects.

TRIAL REGISTRATION

7 September 2009 on ClinicalTrials.gov: NCT00973154.

Corticosteroids in the treatment of dengue shock syndrome

Dengue infection causes significant morbidity and mortality in over 100 countries worldwide, and its incidence is on the rise. The pathophysiological basis for the development of severe dengue, characterized by plasma leakage and the “shock syndrome” are poorly understood. No specific treatment or vaccine is available, and careful monitoring and judicious administration of fluids forms the mainstay of management at present. It is postulated that vascular endothelial dysfunction, induced by cytokine and chemical mediators, is an important mechanism of plasma leakage. Although corticosteroids are potent modulators of the immune system, their role in pharmacological doses in modulating the purported immunological effects that take place in severe dengue has been a subject of controversy. The key evidence related to the role of corticosteroids for various manifestations of dengue are reviewed here. In summary, there is currently no high-quality evidence supporting the beneficial effects of corticosteroids for treatment of shock, prevention of serious complications, or increasing platelet counts. Non-randomized trials of corticosteroids given as rescue medication for severe shock have shown possible benefit. Nonetheless, the evidence base is small, and good-quality trials are lacking. We reiterate the need for well-designed and adequately powered randomized controlled trials of corticosteroids for the treatment of dengue shock.

The Golden Hours in Paediatric Septic Shock—Current Updates and Recommendations

Introduction: Paediatric sepsis is a global health problem. It is the leading cause of mortality in infants and children worldwide. Appropriate and timely initial management in the first hours, often termed as the “golden hours”, has great impact on survival. The aim of this paper is to summarise the current literature and updates on the initial management of paediatric sepsis. Materials and Methods: A comprehensive literature search was performed via PubMed using the search terms: ‘sepsis’, ‘septic shock’, ‘paediatric’ and ‘early goal-directed therapy’. Original and review articles were identified and selected based on relevance to this review. Results: Early recognition, prompt fluid resuscitation and timely administration of antibiotics remain key in the resuscitation of the septic child. Use of steroids and tight glycaemic control in this setting remain controversial. Conclusion: The use of early goal-directed therapy has had significant impact on patient outcomes and protocolised resuscitation of children in septic shock is recommended. Key words: Child, Early goal-directed therapy, Emergency, Sepsis

The Effect of Adrenal Replacement Therapy on Rates of Fungal Colonization and Mortality in Critically Ill Patients Awaiting Liver Transplantation

BACKGROUND

The effect of adrenal replacement therapy (ART) with hydrocortisone on critical endpoints such as infection and mortality in critically ill patients with cirrhosis remains unclear. We evaluated our indications for ART in patients with cirrhosis with clinical symptoms of adrenal insufficiency (AI), and examined the rate of peri-transplant fungal colonization and mortality associated with ART.

METHODS

Seventy-eight patients with cirrhosis admitted to our institution's surgical intensive care unit (ICU) over a 4-year period met criteria for AI by vasopressor requirement and baseline cortisol levels. Outcomes included disposition at 90-days, fungal colonization, and fungal infection in the presence or absence of ART.

RESULTS

In total, 56 patients received hydrocortisone (HC+) while 22 did not (HC-). The HC+ and HC- groups had comparable median Model for End-stage Liver Disease (MELD) scores (26.5 vs. 25, respectively; p=0.93), median ICU lengths of stay (23 vs. 20 days, respectively; p=0.54) and median cortisol levels (18 μg/dL for both, p=0.87). Fungal cultures (FC) from blood, urine or bronchoalveolar lavage/sputum were positive for 44% of HC+, and 40.9% of HC- (p=0.77) had mortality rates between HC+ and HC- groups that were not significantly different (60.7% vs. 50%, respectively; p=0.39; α=0.05). The 90-day outcomes for HC+ vs. HC- (39.3% vs. 50% discharged, respectively; p=0.39; α=0.05) and those surviving to transplant (17.9% vs. 36.4%, respectively; p=0.08; α=0.05) were not significantly different between the two groups.

CONCLUSION

In this small single-center series, we found that steroid administration for AI does not affect the rate of fungal colonization/infection or mortality. Further prospective studies are required to determine the utility of ART and factors affecting the rate of FC and mortality in these patients.

Comparative effect sizes in randomised trials from less developed and more developed countries: meta-epidemiological assessment

OBJECTIVE

To compare treatment effects from randomised trials conducted in more developed versus less developed countries.

DESIGN

Meta-epidemiological study.

DATA SOURCES

Cochrane Database of Systematic Reviews (August 2012).

DATA EXTRACTION

Meta-analyses with mortality outcomes including data from at least one randomised trial conducted in a less developed country and one in a more developed country. Relative risk estimates of more versus less developed countries were compared by calculating the relative relative risks for each topic and the summary relative relative risks across all topics. Similar analyses were performed for the primary binary outcome of each topic.

RESULTS

139 meta-analyses with mortality outcomes were eligible. No nominally significant differences between more developed and less developed countries were found for 128 (92%) meta-analyses. However, differences were beyond chance in 11 (8%) cases, always showing more favourable treatment effects in trials from less developed countries. The summary relative relative risk was 1.12 (95% confidence interval 1.06 to 1.18; P<0.001; I(2)=0%), suggesting significantly more favourable mortality effects in trials from less developed countries. Results were similar for meta-analyses with nominally significant treatment effects for mortality (1.15), meta-analyses with recent trials (1.14), and when excluding trials from less developed countries that subsequently became more developed (1.12). For the primary binary outcomes (127 meta-analyses), 20 topics had differences in treatment effects beyond chance (more favourable in less developed countries in 15/20 cases).

CONCLUSIONS

Trials from less developed countries in a few cases show significantly more favourable treatment effects than trials in more developed countries and, on average, treatment effects are more favourable in less developed countries. These discrepancies may reflect biases in reporting or study design as well as genuine differences in baseline risk or treatment implementation and should be considers when generalising evidence across different settings.

High-volume haemofiltration for sepsis

BACKGROUND

Severe sepsis and septic shock are leading causes of death in the intensive care unit (ICU). This is despite advances in the management of patients with severe sepsis and septic shock including early recognition, source control, timely and appropriate administration of antimicrobial agents, and goal directed haemodynamic, ventilatory and metabolic therapies. High-volume haemofiltration (HVHF) is a blood purification technique which may improve outcomes in critically ill patients with severe sepsis or septic shock. The technique of HVHF has evolved from renal replacement therapies used to treat acute kidney injury (AKI) in critically ill patients in the ICU.

OBJECTIVES

This review assessed whether HVHF improves clinical outcome in adult critically ill patients with sepsis in an ICU setting.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2011, Issue 7); MEDLINE (1990 to August 2011), EMBASE (1990 to August 2011); LILACS (1982 to August 2011), Web of Science (1990 to August 2011), CINAHL (1982 to August 2011) and specific websites.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and quasi-randomized trials comparing HVHF or high-volume haemodiafiltration to standard or usual dialysis therapy; and RCTs and quasi-randomized trials comparing HVHF or high-volume haemodiafiltration to no similar dialysis therapy. The studies involved adults in critical care units.

DATA COLLECTION AND ANALYSIS

Three review authors independently extracted data and assessed trial quality. We sought additional information as required from trialists.

MAIN RESULTS

We included three randomized trials involving 64 participants. Due to the small number of studies and participants, it was not possible to combine data or perform sub-group analyses. One trial reported ICU and 28-day mortality, one trial reported hospital mortality and in the third, the number of deaths stated did not match the quoted mortality rates. No trials reported length of stay in ICU or hospital and one reported organ dysfunction. No adverse events were reported. Overall, the included studies had a low risk of bias.

AUTHORS' CONCLUSIONS

There were no adverse effects of HVHF reported.There is insufficient evidence to recommend the use of HVHF in critically ill patients with severe sepsis and or septic shock except as interventions being investigated in the setting of a randomized clinical trial. These trials should be large, multi-centred and have clinically relevant outcome measures. Financial implications should also be assessed.

Thyroid hormone enhances nitric oxide-mediated bacterial clearance and promotes survival after meningococcal infection

Euthyroid sick syndrome characterized by reduced levels of thyroid hormones (THs) is observed in patients with meningococcal shock. It has been found that the level of THs reflects disease severity and is predictive for mortality. The present study was conducted to investigate the impact of THs on host defense during meningococcal infection. We found that supplementation of thyroxine to mice infected with Neisseria meningitidis enhanced bacterial clearance, attenuated the inflammatory responses and promoted survival. In vitro studies with macrophages revealed that THs enhanced bacteria-cell interaction and intracellular killing of meningococci by stimulating inducible nitric oxide synthase (iNos)-mediated NO production. TH treatment did not activate expression of TH receptors in macrophages. Instead, the observed TH-directed actions were mediated through nongenomic pathways involving the protein kinases PI3K and ERK1/2 and initiated at the membrane receptor integrin αvβ3. Inhibition of nongenomic TH signaling prevented iNos induction, NO production and subsequent intracellular bacterial killing by macrophages. These data demonstrate a beneficial role of THs in macrophage-mediated N. meningitidis clearance. TH replacement might be a novel option to control meningococcal septicemia.

Pneumonia in adults: the practical emergency department perspective

In those patients who are hospitalized with pneumonia, mortality is 15%. Close to 90% of deaths attributed to pneumonia are in patients older than 65 years. This article provides the emergency physician with an understanding of how to make the diagnosis, initiate early and appropriate antibiotic therapy, risk stratify patients with respect to the severity of illness, and recognize indications for admission. The discussion is balanced with an emphasis on cost-effective management, an understanding of the changing spectrum of pathogenesis, and a cognizance toward variable and less common presentations.

Role of human recombinant activated protein C and low dose corticosteroid therapy in sepsis

Despite advances in modern medicine, sepsis remains a complex syndrome that has been associated with significant morbidity and mortality. Multiple organ failure associated with sepsis leads to high mortality and morbidity. About 28 - 50% deaths have been reported in patients with sepsis. The number of sepsis patients is increasing, with considerable burden on healthcare facilities. Various factors leading to a rise in the incidence of sepsis are (1) Improvement of diagnostic procedures (2) Increase in the number of immunocompromised patients taking treatment for various autoimmune disease, carcinomas, organ transplantation (3) Advances in intensive procedures (4) Nosocomial infections (5) Extensive use of antibiotics. With the better understanding of sepsis various modalities to modify pathophysiological response of septic patients have developed. Activated protein C and low-dose corticosteroid therapy have been tried in patients, with variable results.

Corticosteroids for severe sepsis: an evidence-based guide for physicians

Septic shock is characterized by uncontrolled systemic inflammation that contributes to the progression of organ failures and eventually death. There is now ample evidence that the inability of the host to mount an appropriate hypothalamic-pituitary and adrenal axis response plays a major in overwhelming systemic inflammation during infections. Proinflammatory mediators released in the inflamed sites oppose to the anti-inflammatory response, an effect that may be reversed by exogenous corticosteroids. With sepsis, via nongenomic and genomic effects, corticosteroids restore cardiovascular homeostasis, terminate systemic and tissue inflammation, restore organ function, and prevent death. These effects of corticosteroids have been consistently found in animal studies and in most recent frequentist and Bayesian meta-analyses. Corticosteroids should be initiated only in patients with sepsis who require 0.5 μg/kg per minute or more of norepinephrine and should be continued for 5 to 7 days except in patients with poor hemodynamic response after 2 days of corticosteroids and with a cortisol increment of more than 250 nmol/L after a standard adrenocorticotropin hormone (ACTH) test. Hydrocortisone should be given at a daily dose of 200 mg and preferably combined to enteral fludrocortisone at a dose of 50 μg. Blood glucose levels should be kept below 150 mg/dL.

Interpreting systematic reviews: are we ready to make our own conclusions? A cross-sectional study

BACKGROUND

Independent evaluation of clinical evidence is advocated in evidence-based medicine (EBM). However, authors' conclusions are often appealing for readers who look for quick messages. We assessed how well a group of Malaysian hospital practitioners and medical students derived their own conclusions from systematic reviews (SRs) and to what extent these were influenced by their prior beliefs and the direction of the study results.

METHODS

We conducted two cross-sectional studies: one with hospital practitioners (n = 150) attending an EBM course in June 2008 in a tertiary hospital and one with final-year medical students (n = 35) in November 2008. We showed our participants four Cochrane SR abstracts without the authors' conclusions. For each article, the participants chose a conclusion from among six options comprising different combinations of the direction of effect and the strength of the evidence. We predetermined the single option that best reflected the actual authors' conclusions and labelled this as our best conclusion. We compared the participants' choices with our predetermined best conclusions. Two chosen reviews demonstrated that the intervention was beneficial ("positive"), and two others did not ("negative"). We also asked the participants their prior beliefs about the intervention.

RESULTS

Overall, 60.3% correctly identified the direction of effect, and 30.1% chose the best conclusions, having identified both the direction of effect and the strength of evidence. More students (48.2%) than practitioners (22.2%) chose the best conclusions (P < 0.001). Fewer than one-half (47%) correctly identified the direction of effect against their prior beliefs. "Positive" SRs were more likely than "negative" SRs to change the participants' beliefs about the effect of the intervention (relative risk (RR) 1.8, 95% confidence interval 1.3 to 2.6) and "convert" those who were previously unsure by making them choose the appropriate direction of effect (RR 1.9, 95% confidence interval 1.3 to 2.8).

CONCLUSIONS

The majority of our participants could not generate appropriate conclusions from SRs independently. Judicious direction from the authors' conclusions still appears crucial to guiding our health care practitioners in identifying appropriate messages from research. Authors, editors and reviewers should ensure that the conclusions of a paper accurately reflect the results. Similar studies should be conducted in other settings where awareness and application of EBM are different.

Shock: a common consequence of neonatal asphyxia

Neonatal asphyxia is associated with multi-organ hypoxia-ischemia and subsequent dysfunction. The cardiovascular system is frequently affected, causing signs of shock and complicating the neonatal circulatory transition. Hypothermia therapy can improve outcome from neonatal asphyxia without adversely affecting cardiovascular stability. Therapy directed at the cardiovascular system can improve short-term measures of systemic blood flow, but to date has not been demonstrated to improve long-term outcome.

Hydrocortisone administration increases pulmonary artery pressure in asphyxiated newborn piglets reoxygenated with 100% oxygen

In severely asphyxiated neonates developing vasopressor-resistant shock, hydrocortisone is commonly used to improve perfusion. However, its acute haemodynamic effects in asphyxiated neonates are largely unknown. In a swine model of neonatal asphyxia, effects of hydrocortisone on systemic and pulmonary circulations were examined. Piglets (1-3d, 1.5-2.4kg) were acutely instrumented to measure heart rate, systemic and pulmonary artery pressures, and pulmonary artery flow. After 2h of normocapnic hypoxia, animals were resuscitated with 100% oxygen for 1h followed by 21% oxygen for 3h. Intravenous hydrocortisone (1mg/kg) or saline was given in a blinded, randomized fashion 2h after reoxygenation (n=6/group). Haemodynamic parameters, blood gases, plasma cortisol, as well as levels of endothelin-1, nitrite/nitrate, nitrotyrosine, matrix metalloproteinases-2 and -9 in the lung were analysed. Severe hypoxia caused metabolic acidosis (mean pH: 6.91-6.97, mean plasma lactate: 17.2-18.3mM), tachycardia and shock. Hydrocortisone did not affect systemic haemodynamics which recovered with reoxygenation, but it increased pulmonary artery pressure at 90-120min after administration (36±3 vs. 27±2 and 26±1mmHg for hypoxia-reoxygenation control and sham-operated piglets, respectively, P<0.05). In the lung tissue, hydrocortisone significantly increased endothelin-1 and nitrite/nitrate levels, but had no effect on nitrotyrosine. Further, it decreased lung matrix metalloproteinase-9, but not matrix metalloproteinase-2, activity, which were both elevated with hypoxia-reoxygenation. It is most likely that the increase in pulmonary artery pressure observed after hydrocortisone treatment was associated with increased endothelin-1 level in the lung. Our findings caution the use of hydrocortisone as a first-intention treatment of shock in asphyxiated neonates.

Comparative effectiveness of medical interventions in adults versus children

OBJECTIVE

To estimate the comparative effectiveness of medical interventions in adults versus children.

STUDY DESIGN

We identified from the Cochrane Database of Systematic Reviews (Issue 1, 2007) meta-analyses with data on at least 1 adult and 1 pediatric randomized trial with binary primary efficacy outcome. For each meta-analysis, we calculated the summary odds ratio of the adult trials and the pediatric trials, respectively; the relative odds ratio (ROR) of the adult versus pediatric odds ratios per meta-analysis; and the summary ROR across all meta-analyses. ROR <1 means that the experimental intervention is more unfavorable in children than adults.

RESULTS

Across 128 eligible meta-analyses (1051 adult and 343 pediatric trials), the summary ROR did not show a statistically significant difference between adults and children (0.96; 95% confidence intervals, 0.86 to 1.08). However, in all meta-analyses except for 1, the individual ROR's 95% confidence intervals could not exclude a relative difference in efficacy over 20%. In two-thirds, the relative difference in observed point estimates exceeded 50%. Nine statistically significant discrepancies were identified; 4 of them were also clinically important.

CONCLUSIONS

Treatment effects are on average similar in adults and children, but available evidence leaves large uncertainty about their relative efficacy. Clinically important discrepancies may occur.

Taking the septic patient to the operating room

The acutely septic patient is a multifaceted challenge for the anesthetist. Unlike most elective surgery patients, acutely septic patients have severe systemic disease before the physiologic insults of anesthesia and surgery. The decision to operate is usually informed by the urgent or emergent need to correct a severe surgical problem and weighed against the higher risks of morbidity and mortality from the procedure itself. The care of the septic patient in the intensive care unit can help guide operating room management. However, the acuity and time course of intraoperative events, including hemorrhage and drug-induced shock states, compel the anesthetist to respond aggressively with therapies that may or may not be strongly substantiated with long-term data in the intensive care unit setting. The anesthesiologist must place considerations concerning short-term survival from the acute insult of surgery ahead of longer-term considerations.

Role of steroids in septic shock: assessment of knowledge, attitudes and practices among intensivists practising in Hyderabad

Context:

Use of steroids in septic shock is an issue of contention, more so with two major trials reporting conflicting results.

Aims:

To assess the current knowledge, attitudes and practices (KAP) related to the role of steroids in septic shock among intensivists practising in Hyderabad.

Setting, Design, Materials and Methods:

Questionnaires containing 10 questions pertaining to the role of steroids in septic shock, were distributed to 76 intensivists during the monthly critical care meeting.

Results:

A great majority of intensivists (82%) agreed that the role of steroids is restricted to septic shock not responding to vasopressors. There was no clear consensus regarding the role of corticotropin stimulation test or the timing of total cortisol level testing, if it has to be performed. Hydrocortisone was clearly the choice of steroid for most intensivists and intravenous bolus injection being the preferred route of administration. There was no agreement regarding the dose of steroids, the role of fludrocortisone and whether steroids should be tapered. Most of the respondents did not extend the steroid therapy beyond seven days and the most common side effect reported was hyperglycemia.

Conclusion:

There is a lot of ambiguity in the knowledge, attitudes or practices regarding role of steroids in septic shock among intensivists in Hyderabad. Uniform policies and protocols need to be devised at institutional level, with multispecialty inputs, and doctors need to be familiarized accordingly.

Adjunctive therapies in severe sepsis and septic shock: current place of steroids

For more than five decades, the use of corticosteroids as an adjunctive therapy to treat severe sepsis and septic shock has incited consistent debate. Negative results of the Corticosteroid Therapy of Septic Shock (CORTICUS) study evoked a revision of Surviving Sepsis Campaign guidelines suggesting a more restricted use of low-dose hydrocortisone only in patients with severe septic shock. Hemodynamic improvement by low-dose steroids was evident and independent from adrenal insufficiency, but did not improve survival. The roles of cortisol measurement and adrenal function tests for treatment decisions have been questioned. An international task force introduced the concept of critical illness-related corticosteroid insufficiency, which challenges the predominant role of adrenal dysfunction and underscores sustained inflammation due to tissue steroid resistance. Whether moderate steroid doses induce superinfections and muscle weakness is unclear. This article reviews recent publications, actual recommendations, ongoing discussions, and future perspectives.

Forget me not

A 37-year-old man presented with a facial abscess that progressed to external ophthalmoplegia and proptosis. Neuroimaging was consistent with cavernous sinus thrombosis. The diagnosis, management options, and management controversies of septic cavernous sinus thrombosis are discussed, including neuroimaging, antibiotic choice, and the role of corticosteroids and anticoagulation.

NETWORKS, BIOLOGY AND SYSTEMS ENGINEERING: A CASE STUDY IN INFLAMMATION

Biological systems can be modeled as networks of interacting components across multiple scales. A central problem in computational systems biology is to identify those critical components and the rules that define their interactions and give rise to the emergent behavior of a host response. In this paper we will discuss two fundamental problems related to the construction of transcription factor networks and the identification of networks of functional modules describing disease progression. We focus on inflammation as a key physiological response of clinical and translational importance.

In silico simulation of corticosteroids effect on an NFkB- dependent physicochemical model of systemic inflammation

BACKGROUND

During the onset of an inflammatory response signaling pathways are activated for "translating" extracellular signals into intracellular responses converging to the activation of nuclear factor (NF)-kB, a central transcription factor in driving the inflammatory response. An inadequate control of its transcriptional activity is associated with the culmination of a hyper-inflammatory response making it a desired therapeutic target. Predicated upon the nature of the response, a systems level analysis might provide rational leads for the development of strategies that promote the resolution of the response.

METHODOLOGY AND FINDINGS

A physicochemical host response model is proposed to integrate biological information in the form of kinetic rules and signaling cascades with pharmacokinetic models of drug action for the modulation of the response. The unifying hypothesis is that the response is triggered by the activation of the NFkB signaling module and corticosteroids serve as a template for assessing anti-inflammatory strategies. The proposed in silico model is evaluated through its ability to predict and modulate uncontrolled responses. The pre-exposure of the system to hypercortisolemia, i.e. 6 hr before or simultaneously with the infectious challenge "reprograms" the dynamics of the host towards a balanced inflammatory response. However, if such an intervention occurs long before the inflammatory insult a symptomatic effect is observed instead of a protective relief while a steroid infusion after inducing inflammation requires much higher drug doses.

CONCLUSIONS AND SIGNIFICANCE

We propose a reversed engineered inflammation model that seeks to describe how the system responds to a multitude of external signals. Timing of intervention and dosage regimes appears to be key determinants for the protective or symptomatic effect of exogenous corticosteroids. Such results lie in qualitative agreement with in vivo human studies exposed both to LPS and corticosteroids under various time intervals thus improving our understanding of how interacting modules generate a behavior.

Experimental therapeutic strategies for severe sepsis: mediators and mechanisms

Severe sepsis is the leading cause of mortality in intensive care units. The limited ability of current therapies to reduce sepsis mortality rates has fueled research efforts for the development of novel treatment strategies. Through the close collaboration between clinicians and scientists, progress can be seen in the struggle to develop effective therapeutic approaches for the treatment of sepsis and other immune and inflammatory disorders. Indeed, significant advances in intensive care, such as lung protective mechanical ventilation, improved antibiotics, and superior monitoring of systemic perfusion, are improving patient survival. Nonetheless, specific strategies that target the pathophysiological disorders in sepsis patients are essential to further improve clinical outcomes. This article reviews current clinical management approaches and experimental interventions that target pleiotropic or late-acting inflammatory mediators like caspases, C5a, MIF, and HMGB1, or the body's endogenous inflammatory control mechanisms such as the cholinergic anti-inflammatory pathway. These inflammatory mediators and anti-inflammatory mechanisms, respectively, show significant potential for the development of new experimental therapies for the treatment of severe sepsis and other infectious and inflammatory disorders.

Translational potential of systems-based models of inflammation

A critical goal of translational research is to convert basic science to clinically relevant actions related to disease prevention, diagnosis, and eventually enable physicians to identify and evaluate treatment strategies. Integrated initiatives are identified as valuable in uncovering the mechanism underpinning the progression of human diseases. Tremendous opportunities have emerged in the context of systems biology that aims at the deconvolution of complex phenomena to their constituent elements and the quantification of the dynamic interactions between these components through the development of appropriate computational and mathematical models. In this review, we discuss the potential role systems-based translation research can have in the quest to better understand and modulate the inflammatory response.

Clinical review: Critical illness polyneuropathy and myopathy

Critical illness polyneuropathy (CIP) and myopathy (CIM) are major complications of severe critical illness and its management. CIP/CIM prolongs weaning from mechanical ventilation and physical rehabilitation since both limb and respiratory muscles can be affected. Among many risk factors implicated, sepsis, systemic inflammatory response syndrome, and multiple organ failure appear to play a crucial role in CIP/CIM. This review focuses on epidemiology, diagnostic challenges, the current understanding of pathophysiology, risk factors, important clinical consequences, and potential interventions to reduce the incidence of CIP/CIM. CIP/CIM is associated with increased hospital and intensive care unit (ICU) stays and increased mortality rates. Recently, it was shown in a single centre that intensive insulin therapy significantly reduced the electrophysiological incidence of CIP/CIM and the need for prolonged mechanical ventilation in patients in a medical or surgical ICU for at least 1 week. The electrophysiological diagnosis was limited by the fact that muscle membrane inexcitability was not detected. These results have yet to be confirmed in a larger patient population. One of the main risks of this therapy is hypoglycemia. Also, conflicting evidence concerning the neuromuscular effects of corticosteroids exists. A systematic review of the available literature on the optimal approach for preventing CIP/CIM seems warranted.

Endocrine aspects of critical illness

Metabolic disorders and endocrine changes are common and relevant in critically ill patients. Thereby, endocrinopathies, electrolyte or metabolic derangements may either pre-exist or develop, and left unattended, may lead to significant morbidity and mortality. The homeostatic corrections which have emerged in the course of human evolution to cope with the catastrophic events during critical illness involve a complex multisystem endeavour, of which the endocrine contribution is an integral component. Although the repertoire of endocrine changes has been probed in some detail, discerning the vulnerabilities and failures of this system is far more challenging. The ensuing endocrine topics illustrate some of the current issues reflecting attempts to gain an improved insight and clinical outcome for critical illness. Disturbances in glucose and cortisol homeostasis during critical illness are two controversially debated topics in the current literature. The term "hormokine" encompasses the cytokine like behaviour of hormones during inflammation and infections. The concept is based on an ubiquitous expression of calcitonin peptides during sepsis. Adrenomedullin, another member of the calcitonin peptide superfamily, was shown to complement and improve the current prognostic assessment in lower respiratory tract infections. Procalcitonin is the protopye of "hormokine" mediators circulating procalcitonin levels increase several 10,000-fold during sepsis improve the clinical assessment especially of respiratory tract infections and sepsis safely and markedly reduces antibiotic usage in non-bacterial respiratory tract infections and meningitis. Adrenomedullin, another member of the calcitonin peptide superfamily, was shown to complement and improve the current prognostic assessment in lower respiratory tract infections. Hormokines are not only biomarkers of infection. Hormokines are also pivotal inflammatory mediators. Like all mediators, their role during systemic infections is basically beneficial, possibly to combat invading microbes. Yet, with increasing levels they can become harmful for their host. Multiple mechanisms of action were proposed. In several animal models the modulation and neutralization of hormokines during infection was shown to improve survival and thus might open new treatment options for severe infections, especially of the respiratory tract.

Que reste-t-il de l'insuffisance surrénale post-corticothérapie?

Adrenal insufficiency (AI) induced by glucocorticoids was first described more than 50 years ago in patients undergoing surgical stress. Although considered the most frequent cause of AI, the true incidence of this complication of glucocorticoid treatment remains unknown. No factors are known to predict AI after glucocorticoid treatment. In particular, neither the dose nor the duration of treatment seems predictive. The minimum dose of cortisol necessary for the body to cope with medical or surgical stress is unknown. The adrenocorticotropin test is often used during corticosteroid withdrawal because it is well correlated with adrenal response to surgical stress, but not with clinical events. Studies over the past 15 years have shown that the perioperative risk of AI has been overestimated and that hydrocortisone doses should be decreased. A prospective study of patients after steroid withdrawal is the only means of assessing the true incidence of this complication to propose a rational strategy to prevent it.

Cytokine-mediated regulation of urea transporters during experimental endotoxemia

Acute renal failure (ARF) is a frequent complication of sepsis and has a high mortality. Sepsis-induced ARF is known to be associated with significant impairment of tubular capacity. However, the pathogenesis of endotoxemic tubular dysfunction with failure of urine concentration is poorly understood. Urea plays an important role in the urinary concentrating mechanism and expression of the urea transporters UT-A1, UT-A2, UT-A3, UT-A4, and UT-B is essential for tubular urea reabsorption. The present study attempts to assess the regulation of renal urea transporters during severe inflammation in vivo. Lipopolysaccharide-(LPS)-injected mice presented with reduced glomerular filtration rate, fractional urea excretion, and inner medulla osmolality associated with a marked decrease in expression of all renal urea transporters. Similar alterations were observed after application of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, interferon (IFN)-gamma, or IL-6. LPS-induced downregulation of urea transporters was not affected in knockout mice with deficient TNF-alpha, IL-receptor-1, IFN-gamma, or IL-6. Glucocorticoid treatment inhibited LPS-induced increases of tissue TNF-alpha, IL-1beta, IFN-gamma, or IL-6 concentration, diminished LPS-induced renal dysfunction, and attenuated the downregulation of renal urea transporters. Renal ischemia induced by renal artery clipping did not influence the expression of urea transporters. Our data demonstrate that renal urea transporters are downregulated by severe inflammation, which likely accounts for tubular dysfunction. Furthermore, they suggest that the downregulation of renal urea transporters during LPS-induced ARF is mediated by proinflammatory cytokines and is independent from renal ischemia because of sepsis-induced hypotension.

Regulation of renal sodium transporters during severe inflammation

Sepsis-associated acute renal failure is characterized by decreased GFR and tubular dysfunction. The pathogenesis of endotoxemic tubular dysfunction with failure in urine concentration and increased fractional sodium excretion is poorly understood. This study investigated the regulation of renal sodium transporters during severe inflammation in vivo and in vitro. Injection of high-dosage LPS reduced BP and GFR, increased fractional sodium excretion, and strongly decreased the expression of Na(+)/H(+)-exchanger, renal outer medullary potassium channel, Na(+)-K(+)-2Cl(-) co-transporter, epithelial sodium channel, and Na(+)/K(+)-ATPase in mice. Also, injection of TNF-alpha, IL-1beta, or IFN-gamma decreased renal function and expression of renal sodium transporters. LPS-induced downregulation of sodium transporters was not affected in cytokine-knockout mice. However, supplementary glucocorticoid treatment, which inhibited LPS-induced increase of tissue cytokine concentrations, attenuated LPS-induced renal dysfunction and downregulation of tubular sodium transporters. Injection of low-dosage LPS increased renal tissue cytokines and downregulated renal sodium transporters without arterial hypotension. In vitro, in cortical collecting duct cells, cytokines also decreased expression of renal outer medullary potassium channel, epithelial sodium channel, and Na(+)/K(+)-ATPase. Renal hypoperfusion by renal artery clipping did not influence renal sodium transporter expression, in contrast to renal ischemia-reperfusion injury, which depressed transporter expression. These findings demonstrate downregulation of renal sodium transporters that likely accounts for tubular dysfunction during inflammation. These data suggest that alteration of renal sodium transporters during LPS-induced acute renal failure is mediated by cytokines rather than renal ischemia. However, in a complex in vivo model of severe inflammation, the possible presence and influence of renal hypoperfusion and reperfusion on the expression of renal sodium transporters cannot be completely excluded.

The hypothalamic-pituitary-adrenal axis in critical illness

The hypothalamic-pituitary-adrenal response to stress is a dynamic process. The homeostatic corrections that have emerged in the course of human evolution to cope with the catastrophic events during critical illness involve a complex multisystem endeavor. Although the repertoire of endocrine changes has been probed in some detail, discerning the vulnerabilities and failures of this system is far more challenging. One of the most controversially debated topics in the current literature is the characterization and optimal treatment of allegedly inadequate adaptations of the hypothalamic-pituitary-adrenal axis during critical illness. This outline attempts to touch briefly some of the debated issues, stir the discussion, and thereby contribute to resolving the dispute.

Management of sepsis during the early "golden hours"

Severe sepsis and septic shock are common causes of morbidity and mortality. Interventions directed at specific endpoints, when initiated early in the "golden hours" of patient arrival at the hospital, seem to be promising. Early hemodynamic optimization, administration of appropriate antimicrobial therapy, and effective source control of infection are the cornerstones of successful management. In patients with vasopressor-dependent septic shock, provision of physiologic doses of replacement steroids may result in improved survival. Administration of drotrecogin alfa (activated), (activated protein C) has been shown to improve survival in patients with severe sepsis and septic shock who have a high risk of mortality. In this article we review the multi-modality approach to early diagnosis and intervention in the therapy of patients with severe sepsis and septic shock.

Regulation of renal glucose transporters during severe inflammation

Severe sepsis is accompanied by acute renal failure (ARF) with renal tubular dysfunction and glucosuria. In this study, we aimed to determine the regulation of renal tubular glucose transporters during severe experimental inflammation. Male C57BL/6J mice were injected with LPS or proinflammatory cytokines, and renal perfusion, glomerular filtration rate (GFR), fractional glucose excretion, and expression of tubular glucose transporters were determined. We found a decreased plasma glucose concentration with impaired renal tissue perfusion and GFR and increased fractional glucose excretion associated with decreased expression of SGLT2, SGLT3, and GLUT2 after LPS injection. Similar alterations were observed after application of TNF-alpha, IL-1beta, IL-6, or IFN-gamma. To clarify the role of proinflammatory cytokines, we performed LPS injections in knockout mice with deficiencies for TNF-alpha, IL-1 receptor type 1, IFN-gamma, or IL-6 as well as LPS injections in glucocorticoid-treated wild-type mice. LPS-induced alterations of glucose transporters also were present in single-cytokine knockout mice. In contrast, glucocorticoid treatment clearly attenuated LPS-induced changes in renal glucose transporter expression and improved GFR and fractional glucose excretion. LPS-induced decrease of renal perfusion was not improved by glucocorticoids, indicating a minor role of ischemia in the development of septic renal dysfunction. Our results demonstrate modifications of tubular glucose transporters during severe inflammation that are probably mediated by proinflammatory cytokines and account for the development of ARF with increased fractional glucose excretion. In addition, our findings provide an explanation why single anti-cytokine strategies fail in the therapy of septic patients and contribute to an understanding of the beneficial effects of glucocorticoids on septic renal dysfunction.

Adrenal insufficiency in severe West Nile Virus infection

OBJECTIVE

To explore adrenal function in severe West Nile virus (WNV) infection.

DESIGN AND SETTING

Prospective interventional cohort study in a medical ICU of a teaching hospital.

PATIENTS

Ten consecutive patients (seven men, mean age 64+/-12years, mean SAPS II 26+/-6) with definite diagnosis of WNV related meningoencephalitis and variable proportion of organ/system failure. All patients had fever (mean body temperature 39+/-1 degrees C) and altered mental status (mean Glasgow Coma Score 11+/-2). Mean SOFA score was 9+/-2; eight patients had systemic inflammatory response syndrome, five septic shock, and six acute respiratory failure (usually from central origin) requiring mechanical ventilation.

INTERVENTIONS

A short corticotropin test was performed in each patient to assess the adrenal function.

MEASUREMENTS AND RESULTS

Cortisol response was defined as the difference between baseline and corticotropin-stimulated peak. Absolute adrenal insufficiency was defined by a baseline cortisol level below 15 microg/dl (415 nmol/l). Relative insufficiency was defined by a cortisol response of 9 microg/dl (250 nmol/l) or less. Relative adrenal insufficiency, defined by a corticotropin response below 9 microg/dl, was observed in seven while the remaining three had normal cortisol response; six out of these seven died in the ICU. All patients with normal adrenal function survived.

CONCLUSION

Adrenal insufficiency is frequent in severe WNV infection and carries a poor outcome. In the absence of specific effective treatment, our data provide a rational to investigate a supplemental corticosteroid treatment in a controlled trial.

Adrenal axis function does not appear to be associated with hemodynamic improvement in septic shock patients systematically receiving glucocorticoid therapy

OBJECTIVE

There is mounting evidence showing the value of low-dose corticosteroids in patients with septic shock requiring vasopressor therapy. It remains unclear whether adrenal function tests should be carried out systematically to guide the decision on glucocorticoid therapy.

METHODS

The retrospective study was conducted in 52 patients in three university hospital ICUs. We included consecutive patients with catecholamine-dependent septic shock who had not received ketoconazole, glucocorticoids, or etomidate in the 24 h before the ACTH test, and who had survived to day 3 after the shock onset. All patients had a 250-microg ACTH test before systematic glucocorticoid therapy was started. Various definitions of relative adrenal insufficiency were used (based on cortisol basal level and/or change in cortisol level after ACTH stimulation). We defined hemodynamic improvement as a 50% reduction in the vasoactive agent dose in the 3 days following the initiation of glucocorticoid treatment. The relationship between the hemodynamic improvement and the results of the adrenal function tests was analyzed.

RESULTS

Hemodynamic improvement occurred in 29 patients (55.8%). Baseline characteristics, sites of infection, types of micro-organisms and antibiotic management did not differ between patients with and those without hemodynamic improvement. Relative adrenal insufficiency whatever the definition was not associated with hemodynamic improvement.

CONCLUSION

In catecholamine-dependent septic shock patients managed with systematic glucocorticoid therapy the results of ACTH stimulation do not predict hemodynamic improvement.

Clinical review: a systematic review of corticosteroid use in infections

Traditional teaching suggests that corticosteroids should be avoided during acute infectious episodes for fear of compromising the immune response. However, the outcome benefit shown through steroid administration in early septic shock implies this paranoia may be misplaced. We therefore performed a systematic review of the literature to identify the current strength of evidence for the use of corticosteroids in specified infections, and to make appropriate graded recommendations.

Adjunctive Corticosteroids in Adults with Bacterial Meningitis

Bacterial meningitis is a complex disorder in which neurologic injury is caused, in part, by the causative organism and, in part, by the host's own inflammatory response. In studies of experimental bacterial meningitis, adjuvant treatment with corticosteroids, specifically dexamethasone, has beneficial effects. On the basis of these experimental studies, several clinical trials were undertaken to determine the effects of adjunctive corticosteroids in patients with bacterial meningitis. On the basis of overall benefit without detrimental effects by subgroup analysis, dexamethasone therapy should be initiated before or with the first dose of antibiotic and should be continued in most patients with community-acquired acute bacterial meningitis. For patients with a low suspicion of meningitis but an urgent need for antibiotics before cerebrospinal fluid can be obtained, we recommend initiation of treatment with dexamethasone, with discontinuation of dexamethasone therapy as soon as the diagnosis has been excluded.

Corticosteroids for severe sepsis and septic shock: a systematic review and meta-analysis

OBJECTIVE

To assess the effects of corticosteroids on mortality in patients with severe sepsis and septic shock.

DATA SOURCES

Randomised and quasi-randomised trials of corticosteroids versus placebo (or supportive treatment alone) retrieved from the Cochrane infectious diseases group's trials register, the Cochrane central register of controlled trials, Medline, Embase, and LILACS.

REVIEW METHOD

Two pairs of reviewers agreed on eligibility of trials. One reviewer entered data on to the computer and four reviewers checked them. We obtained some missing data from authors of trials and assessed methodological quality of trials.

RESULTS

16/23 trials (n = 2063) were selected. Corticosteroids did not change 28 day mortality (15 trials, n = 2022; relative risk 0.92, 95% confidence interval 0.75 to 1.14) or hospital mortality (13 trials, n = 1418; 0.89, 0.71 to 1.11). There was significant heterogeneity. Subgroup analysis on long courses (> or = 5 days) with low dose (< or = 300 mg hydrocortisone or equivalent) corticosteroids showed no more heterogeneity. The relative risk for mortality was 0.80 at 28 days (five trials, n = 465; 0.67 to 0.95) and 0.83 at hospital discharge (five trials, n = 465, 0.71 to 0.97). Use of corticosteroids reduced mortality in intensive care units (four trials, n = 425, 0.83, 0.70 to 0.97), increased shock reversal at 7 days (four trials, n = 425; 1.60, 1.27 to 2.03) and 28 days (four trials, n = 425, 1.26, 1.04 to 1.52) without inducing side effects.

CONCLUSIONS

For all trials, regardless of duration of treatment and dose, use of corticosteroids did not significantly affect mortality. With long courses of low doses of corticosteroids, however, mortality at 28 days and hospital morality was reduced.

Corticosteroids for treating severe sepsis and septic shock

BACKGROUND

Sepsis may be complicated by impaired corticosteroid production. Giving corticosteroids could potentially benefit patients.

OBJECTIVES

To examine the effects of corticosteroids on death at one month in patients with severe sepsis and septic shock.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group's trial register (August 2003), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2003), MEDLINE (August 2003), EMBASE (August 2003), LILACS (August 2003), reference lists of articles, and also contacted trial authors.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials of corticosteroids versus placebo or supportive treatment in severe sepsis and septic shock.

DATA COLLECTION AND ANALYSIS

Two pairs of reviewers agreed the eligibility of trials. One reviewer extracted data, which was checked by the other reviewers and the primary author of the paper whenever possible. We obtained some missing data from the trial authors. We assessed trial methodological quality.

MAIN RESULTS

We identified 15 trials (n =2023). Corticosteroids did not change 28-day all-cause mortality (15 trials, n = 2022, relative risk (RR) 0.92, 95% confidence interval (CI) 0.75 to 1.14; random effects model) and hospital mortality (13 trials, n = 1418, RR 0.89, 95% CI 0.71 to 1.11; random effects model); however, there was statistically significant heterogeneity, with some evidence that this was related to the dosing strategy. Corticosteroids reduced intensive care unit mortality (4 trials, n = 425, RR 0.83, 95% CI 0.70 to 0.97), increased the proportion of shock reversal by day 7 (6 trials, n = 728, RR 1.22, 95% CI 1.06 to 1.40) and by day 28 (4 trials, n = 425, RR 1.26, 95% CI 1.04 to 1.52), without increasing the rate of gastroduodenal bleeding (10 trials, n = 1321, RR 1.16, 95% CI 0.82 to 1.65), superinfection (12 trials, n = 1705, RR 0.93, 95% CI 0.73 to 1.18), and of hyperglycaemia (6 trials, n = 608, RR 1.22, 0.84 to 1.78).

REVIEWER'S CONCLUSIONS

Overall, corticosteroids did not change 28-day mortality and hospital mortality in severe sepsis and septic shock. Long course of low dose corticosteroids reduced 28-day all-cause mortality, and intensive care unit and hospital mortality.