Effect of Corticosteroids on Mortality and Clinical Cure in Community-Acquired Pneumonia: A Systematic Review, Meta-analysis, and Meta-regression of Randomized Control Trials

Understanding, assessing and treating immune, endothelial and haemostasis dysfunctions in bacterial sepsis

The interplay between the immune system, coagulation, and endothelium is critical in regulating the host response to infection. However, in sepsis and other critical illnesses, a dysregulated immune response can lead to excessive alterations in these mechanisms, resulting in coagulopathy, endothelial dysfunction, and multi-organ dysfunction. This review aims to provide a comprehensive analysis of the pathophysiological mechanisms that govern the complex interplay between immune dysfunction, endothelial dysfunction, and coagulation in sepsis. It emphasises clinical significance, evaluation methods, and potential therapeutic interventions. Understanding these mechanisms is essential for developing effective treatments that can modulate the immune response, mitigate thrombosis, restore endothelial function, and ultimately improve patient survival.

Comparison of performances between risk scores for predicting mortality at 30 days in patients with community acquired pneumonia

BACKGROUND

Risk scores facilitate the assessment of mortality risk in patients with community-acquired pneumonia (CAP). Despite their utilities, there is a scarcity of evidence comparing the various RS simultaneously. This study aims to evaluate and compare multiple risk scores reported in the literature for predicting 30-day mortality in adult patients with CAP.

METHODS

A retrospective cohort study on patients diagnosed with CAP was conducted across two hospitals in Colombia. The areas under receiver operating characteristic curves (ROC-curves) were calculated for the outcome of survival or death at 30 days using the scores obtained for each of the analyzed questionnaires.

RESULTS

A total of 7454 potentially eligible patients were included, with 4350 in the final analysis, of whom 15.2% (662/4350) died within 30 days. The average age was 65.4 years (SD: 21.31), and 59.5% (2563/4350) were male. Chronic kidney disease was 3.7% (9.2% vs. 5.5%; p < 0.001) (OR: 1.85) higher in subjects who died compared to those who survived. Among the patients who died, 33.2% (220/662) presented septic shock compared to 7.3% (271/3688) of the patients who survived (p < 0.001). The best performances at 30 days were shown by the following scores: PSI, SMART-COP and CURB 65 scores with the areas under ROC-curves of 0.83 (95% CI: 0.8-0.85), 0.75 (95% CI: 0.66-0.83), and 0.73 (95% CI: 0.71-0.76), respectively. The RS with the lowest performance was SIRS with the area under ROC-curve of 0.53 (95% CI: 0.51-0.56).

CONCLUSION

The PSI, SMART-COP and CURB 65, demonstrated the best diagnostic performances for predicting 30-day mortality in patients diagnosed with CAP. The burden of comorbidities and complications associated with CAP was higher in patients who died.

The life-saving benefit of dexamethasone in severe COVID-19 is linked to a reversal of monocyte dysregulation

Dexamethasone is a life-saving treatment for severe COVID-19, yet its mechanism of action is unknown, and many patients deteriorate or die despite timely treatment initiation. Here, we identify dexamethasone treatment-induced cellular and molecular changes associated with improved survival in COVID-19 patients. We observed a reversal of transcriptional hallmark signatures in monocytes associated with severe COVID-19 and the induction of a monocyte substate characterized by the expression of glucocorticoid-response genes. These molecular responses to dexamethasone were detected in circulating and pulmonary monocytes, and they were directly linked to survival. Monocyte single-cell RNA sequencing (scRNA-seq)-derived signatures were enriched in whole blood transcriptomes of patients with fatal outcome in two independent cohorts, highlighting the potential for identifying non-responders refractory to dexamethasone. Our findings link the effects of dexamethasone to specific immunomodulation and reversal of monocyte dysregulation, and they highlight the potential of single-cell omics for monitoring in vivo target engagement of immunomodulatory drugs and for patient stratification for precision medicine approaches.

Steroids in the Management of Ionotropic-Resistant Septic Shock: A Comprehensive Review of Efficacy and Outcomes

Septic shock is a critical condition characterized by persistent hypotension despite adequate fluid resuscitation and the use of vasopressors, often accompanied by multi-organ dysfunction. A challenging subset, ionotropic-resistant septic shock, persists despite ionotropic support. Steroids have been explored as a treatment for septic shock due to their anti-inflammatory properties and potential to improve hemodynamic stability. This review aims to evaluate the efficacy and outcomes of steroid therapy in managing ionotropic-resistant septic shock, assessing its impact on mortality, hemodynamic parameters, and adverse effects. A comprehensive review of the current literature, including randomized controlled trials, observational studies, and clinical guidelines, was conducted. Key studies, such as the CORTICUS and ADRENAL trials, were analyzed to determine the effectiveness of steroid regimens, specifically low-dose hydrocortisone, in patients with septic shock resistant to ionotropic agents. Evidence from recent trials indicates that low-dose hydrocortisone therapy can improve hemodynamic stability and reduce mortality in patients with septic shock, including those with ionotropic resistance. However, the benefits may vary depending on the timing of intervention, patient characteristics, and the presence of contraindications. Steroid therapy is associated with potential adverse effects, including secondary infections, glucose dysregulation, and gastrointestinal issues. Steroid therapy, particularly low-dose hydrocortisone, appears to be an effective adjunctive treatment for ionotropic-resistant septic shock, offering improved shock reversal and reduced mortality. Nonetheless, careful consideration of the risks and benefits is essential, and ongoing research is needed to refine treatment protocols and optimize patient outcomes. This review provides a detailed synthesis of current evidence and offers recommendations for clinical practice and future research in the management of septic shock resistant to ionotropic agents.

EDucated: The emergency medicine pharmacotherapy literature of 2023

The purpose of this article is to summarize pharmacotherapy related emergency medicine (EM) literature indexed in 2023. Articles were selected utilizing a modified Delphi approach. The table of contents from pre-determined journals were reviewed and independently evaluated via the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system by paired authors. Pharmacotherapy-related publications deemed to be GRADE 1A and 1B were reviewed by the collective group for inclusion in the review. In all, this article summarizes and provides commentary on the potential clinical impact of 13 articles, 6 guidelines, and 5 meta-analyses covering topics including guideline releases and updates on rapid sequence intubation in the critically ill, managing cardiac arrest or life-threatening toxicity due to poisoning, and management of major bleeding following trauma. Also discussed are ongoing controversies surrounding fluid resuscitation, time and treatment modalities for ischemic stroke, steroid use in community-acquired pneumonia, targeted blood product administration, and much more.

Guidelines for Antibiotics Prescription in Critically Ill Patients

How to cite this article: Khilnani GC, Tiwari P, Mittal S, Kulkarni AP, Chaudhry D, Zirpe KG, et al. Guidelines for Antibiotics Prescription in Critically Ill Patients. Indian J Crit Care Med 2024;28(S2):S104-S216.

Corticosteroids in critically ill patients: A narrative review

Corticosteroids have been utilized in modern medicine for decades. Many indications have been investigated across various treatment settings with both benefit and harm observed. Given the instability of critically ill patients, the increased risk of corticosteroid-related complications, and the pervasive comorbidities, patients who receive corticosteroids must be carefully managed. Common critical care disease states in which corticosteroids have been studied and are routinely utilized include acute respiratory distress syndrome, adrenal insufficiency, angioedema, asthma, chronic obstructive pulmonary disease, community-acquired pneumonia, coronavirus disease 2019, septic shock, and spinal cord injury. Benefits of corticosteroids include an improvement in disease state-specific outcomes, decreased hospital length of stay, decreased mechanical ventilatory support, and decreased mortality. The harm of corticosteroids is well documented through adverse effects that include, but are not limited to, hyperglycemia, tachycardia, hypertension, agitation, delirium, anxiety, immunosuppression, gastrointestinal bleeding, fluid retention, and muscle weakness. Furthermore, corticosteroids are associated with increased health care costs through adverse effects as well as drug acquisition and administration costs. Given the assortment of agents, dosing, benefits, risks, and utilization in the critical care setting, there may be difficulty with identifying the appropriate places for use of corticosteroids in therapy. There currently exists no comprehensive report detailing the use of corticosteroids in the aforementioned disease states within the critical care setting. This narrative review sets out to describe these in detail.

Unanswered Questions in the Guidelines for Antibiotic Prescription in Critically Ill Patients

How to cite this article: Nath SS, Nachimuthu N, Bhagyashree, Singh S. Unanswered Questions in the Guidelines for Antibiotic Prescription in Critically Ill Patients. Indian J Crit Care Med 2024;28(7):715-716.

Author Response: Unanswered Questions and Contradictory Statements in the Antibiotics Prescription Guidelines

How to cite this article: Khilnani GC, Tiwari P, Mittal S. Author Response: Unanswered Questions and Contradictory Statements in the Antibiotics Prescription Guidelines. Indian J Crit Care Med 2024;28(7):717-718.

Risk factors analysis and prediction model construction for severe pneumonia in older adult patients

Objective

Pneumonia is a common and serious infectious disease that affects the older adult population. Severe pneumonia can lead to high mortality and morbidity in this group. Therefore, it is important to identify the risk factors and develop a prediction model for severe pneumonia in older adult patients.

Method

In this study, we collected data from 1,000 older adult patients who were diagnosed with pneumonia and admitted to the intensive care unit (ICU) in a tertiary hospital. We used logistic regression and machine learning methods to analyze the risk factors and construct a prediction model for severe pneumonia in older adult patients. We evaluated the performance of the model using accuracy, sensitivity, specificity, area under the receiver operating characteristic curve (AUC), and calibration plot.

Result

We found that age, comorbidities, vital signs, laboratory tests, and radiological findings were associated with severe pneumonia in older adult patients. The prediction model had an accuracy of 0.85, a sensitivity of 0.80, a specificity of 0.88, and an AUC of 0.90. The calibration plot showed good agreement between the predicted and observed probabilities of severe pneumonia.

Conclusion

The prediction model can help clinicians to stratify the risk of severe pneumonia in older adult patients and provide timely and appropriate interventions.

Real-world use of glucocorticoids and clinical outcomes in adults hospitalized with community-acquired pneumonia on medical wards

BACKGROUND

Little is known about the real-world use of systemic glucocorticoids to treat patients hospitalized with community-acquired pneumonia (CAP) outside of the intensive care unit (ICU).

METHODS

This retrospective cohort study included 11,588 hospitalizations for CAP without chronic pulmonary disease at seven hospitals in Ontario, Canada. We report physician-level variation in the use of glucocorticoids and trends over time. We investigated the association between glucocorticoid prescriptions and clinical outcomes, using propensity score overlap weighting to account for confounding by indication.

RESULTS

Glucocorticoids were prescribed in 1283 (11.1%) patients, increasing over time from 10.0% in 2010 to 11.9% in 2020 (p = .008). Physician glucocorticoid prescribing ranged from 2.9% to 34.6% (median 10.0%, inter quartile range [IQR]: 6.7%-14.6%). Patients receiving glucocorticoids tended to be younger (median age 73 vs. 79), have higher Charlson comorbidity scores (score of 2 or more: 42.4% vs. 31.0%), more cancer (26.6% vs. 13.2%), more renal disease (11.5% vs. 6.6%), and less dementia (7.8% vs. 14.8%). Patients treated with glucocorticoids had higher rates of in-hospital mortality (weighted Risk Difference = 1.72, 95% confidence interval [95% CI]: 0.16-3.3, p = .033). Glucocorticoid use was not associated with ICU admission, hospital length-of-stay, or 30-day readmission.

CONCLUSION

Glucocorticoids were prescribed in 11.1% of patients hospitalized with CAP outside of ICU and one in four physicians prescribed glucocorticoids in more than 14% of patients. Glucocorticoid use was associated with greater in-hospital mortality, although these findings are limited by large selection effects. Clinicians should exercise caution in prescribing glucocorticoids for nonsevere CAP, and definitive trials are needed in this population.

Candent issues in pneumonia. Reflections from the Fifth Annual Meeting of Spanish Experts 2023

Pneumonia is a multifaceted illness with a wide range of clinical manifestations, degree of severity and multiple potential causing microorganisms. Despite the intensive research of recent decades, community-acquired pneumonia remains the third-highest cause of mortality in developed countries and the first due to infections; and hospital-acquired pneumonia is the main cause of death from nosocomial infection in critically ill patients. Guidelines for management of this disease are available world wide, but there are questions which generate controversy, and the latest advances make it difficult to stay them up to date. A multidisciplinary approach can overcome these limitations and can also aid to improve clinical results. Spanish medical societies involved in diagnosis and treatment of pneumonia have made a collaborative effort to actualize and integrate last expertise about this infection. The aim of this paper is to reflect this knowledge, communicated in Fifth Pneumonia Day in Spain. It reviews the most important questions about this disorder, such as microbiological diagnosis, advances in antibiotic and sequential therapy, management of beta-lactam allergic patient, preventive measures, management of unusual or multi-resistant microorganisms and adjuvant or advanced therapies in Intensive Care Unit.

Circulating Biomarkers of Endothelial Dysfunction Associated With Ventilatory Ratio and Mortality in ARDS Resulting From SARS-CoV-2 Infection Treated With Antiinflammatory Therapies

BACKGROUND

The association of plasma biomarkers and clinical outcomes in ARDS resulting from SARS-CoV-2 infection predate the evidence-based use of immunomodulators.

RESEARCH QUESTION

Which plasma biomarkers are associated with clinical outcomes in patients with ARDS resulting from SARS-CoV-2 infection treated routinely with immunomodulators?

STUDY DESIGN AND METHODS

We collected plasma from patients with ARDS resulting from SARS-CoV-2 infection within 24 h of admission to the ICU between December 2020 and March 2021 (N = 69). We associated 16 total biomarkers of inflammation (eg, IL-6), coagulation (eg, D-dimer), epithelial injury (eg, surfactant protein D), and endothelial injury (eg, angiopoietin-2) with the primary outcome of in-hospital mortality and secondary outcome of ventilatory ratio (at baseline and day 3).

RESULTS

Thirty patients (43.5%) died within 60 days. All patients received corticosteroids and 6% also received tocilizumab. Compared with survivors, nonsurvivors demonstrated a higher baseline modified Sequential Organ Failure Assessment score (median, 8.5 [interquartile range (IQR), 7-9] vs 7 [IQR, 5-8]); P = .004), lower Pao2 to Fio2 ratio (median, 153 [IQR, 118-182] vs 184 [IQR, 142-247]; P = .04), and higher ventilatory ratio (median, 2.0 [IQR, 1.9-2.3] vs 1.5 [IQR, 1.4-1.9]; P < .001). No difference was found in inflammatory, coagulation, or epithelial biomarkers between groups. Nonsurvivors showed higher median neural precursor cell expressed, developmentally down-regulated 9 (NEDD9) levels (median, 8.4 ng/mL [IQR, 7.0-11.2 ng/mL] vs 6.9 ng/mL [IQR, 5.5-8.0 ng/mL]; P = .0025), von Willebrand factor domain A2 levels (8.7 ng/mL [IQR, 7.9-9.7 ng/mL] vs 6.5 ng/mL [IQR, 5.7-8.7 ng/mL]; P = .007), angiopoietin-2 levels (9.0 ng/mL [IQR, 7.9-14.1 ng/mL] vs 7.0 ng/mL [IQR, 5.6-10.6 ng/mL]; P = .01), and syndecan-1 levels (15.9 ng/mL [IQR, 14.5-17.5 ng/mL] vs 12.6 ng/mL [IQR, 10.5-16.1 ng/mL]; P = .01). Only NEDD9 level met the adjusted threshold for significance (P < .003). Plasma NEDD9 level was associated with 60-day mortality (adjusted OR, 9.7; 95% CI, 1.6-60.4; P = .015). Syndecan-1 level correlated with both baseline (ρ = 0.4; P = .001) and day 3 ventilatory ratio (ρ = 0.5; P < .001).

INTERPRETATION

Biomarkers of inflammation, coagulation, and epithelial injury were not associated with clinical outcomes in a small cohort of patients with ARDS uniformly treated with immunomodulators. However, endothelial biomarkers, including plasma NEDD9, were associated with 60-day mortality.

Biological effects of corticosteroids on pneumococcal pneumonia in Mice-translational significance

BACKGROUND

Streptococcus pneumoniae is the most common bacterial cause of community acquired pneumonia and the acute respiratory distress syndrome (ARDS). Some clinical trials have demonstrated a beneficial effect of corticosteroid therapy in community acquired pneumonia, COVID-19, and ARDS, but the mechanisms of this benefit remain unclear. The primary objective of this study was to investigate the effects of corticosteroids on the pulmonary biology of pneumococcal pneumonia in a mouse model. A secondary objective was to identify shared transcriptomic features of pneumococcal pneumonia and steroid treatment in the mouse model and clinical samples.

METHODS

We carried out comprehensive physiologic, biochemical, and histological analyses in mice to identify the mechanisms of lung injury in Streptococcus pneumoniae with and without adjunctive steroid therapy. We also studied lower respiratory tract gene expression from a cohort of 15 mechanically ventilated patients (10 with Streptococcus pneumoniae and 5 controls) to compare with the transcriptional studies in the mice.

RESULTS

In mice with pneumonia, dexamethasone in combination with ceftriaxone reduced (1) pulmonary edema formation, (2) alveolar protein permeability, (3) proinflammatory cytokine release, (4) histopathologic lung injury score, and (5) hypoxemia but did not increase bacterial burden. Transcriptomic analyses identified effects of steroid therapy in mice that were also observed in the clinical samples.

CONCLUSIONS

In combination with appropriate antibiotic therapy in mice, treatment of pneumococcal pneumonia with steroid therapy reduced hypoxemia, pulmonary edema, lung permeability, and histologic criteria of lung injury, and also altered inflammatory responses at the protein and gene expression level. The transcriptional studies in patients suggest that the mouse model replicates some of the features of pneumonia in patients with Streptococcus pneumoniae and steroid treatment. Overall, these studies provide evidence for the mechanisms that may explain the beneficial effects of glucocorticoid therapy in patients with community acquired pneumonia from Streptococcus Pneumoniae.

Corticosteroid in non-COVID-19 induced community-acquired pneumonia, a meta-analysis

BACKGROUND

Corticosteroid treatment in non-COVID-19 induced Community-acquired pneumonia (CAP) remains inconclusive.

OBJECTIVES

We aimed to assess the role of corticosteroid treatment in CAP.

METHODS

We conducted a comprehensive search of online databases, including PubMed, Embase, and Cochrane, to identify articles published from January 1, 2000, to May 5, 2023. Double-blind RCTs were selected. Two authors screened studies and extracted data. The evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach.

RESULTS

We analyzed data from 12 RCTs, involving 2446 patients. Corticosteroids therapy may reduce short-term mortality in patients with severe CAP (sCAP) and shorten the hospital length of stay in patients with CAP. Furthermore, corticosteroids treatment can decrease the risk of requiring mechanical ventilation, developing septic shock and multiple organ dysfunction syndrome (MODS). There were no significant differences between the corticosteroid and control groups concerning gastrointestinal bleeding and nosocomial infection. The use of corticosteroids could increase the risk of hyperglycemia.

CONCLUSION

Corticosteroid treatment for sCAP has the potential to provide benefits in reducing short-term mortality, but this conclusion necessitates more evidence. Besides, we found no evidence that strongly prevents us from using corticosteroids in patients with sCAP or those at risk of progressing to sCAP.

Comparing the efficacy of corticosteroids among patients with community-acquired pneumonia in the ICU versus non-ICU settings: A systematic review and meta-analysis

BACKGROUND

Despite the potential of corticosteroids in treating community-acquired pneumonia (CAP), conflicting evidence exists regarding their effect on mortality. To address this gap and provide new insights, we conducted a pre-specified subgroup meta-analysis of corticosteroid use in CAP patients, focusing on the ICU versus non-ICU subsets.

METHODS

We searched PubMed, Cochrane Central Register of Controlled Trials and SCOPUS from inception to May 2023 for randomized controlled trials (RCTs). The primary outcomes of interest were mortality, need for mechanical ventilation, need for ICU admission, and treatment failure. Secondary outcomes analysed were the need for hospital readmission, length of hospital stay, length of ICU stay, gastrointestinal (GI) bleeding, secondary infections, and hyperglycaemic events. The results were analysed through the random-effects model. A p-value < 0.05 was considered significant.

RESULTS

Eighteen randomized controlled trials (n = 4472) analyzing patients withCAP were included. Our results suggest that corticosteroids significantly reduced the incidence of mortality (RR: 0.66; 95 % CI: 0.54, 0.81; P = <0.0001) and need for mechanical ventilation (RR: 0.57; 95 % CI: 0.44, 0.73; P = <0.00001). It was also observed that corticosteroids significantly decrease the lengths of ICU (MD: -1.67; 95 % CI: -2.97, -0.37; P = 0.01) and hospital stay (MD: -1.94; 95 % CI: -2.89, -0.98; P = 0.0001), while increasing the number of hyperglycemic events (RR: 1.68; 95 % CI: 1.32, 2.12; P = <0.0001) and hospital readmissions (RR: 1.19; 95 % CI: 1.04, 1.37; P = 0.01).

CONCLUSIONS

The results of this meta-analysis demonstrate that corticosteroids yield improved outcomes in CAP patients with regard to reduced mortality and the need for mechanical ventilation. It highlights the need for further large-scale RCTs with the proposed, specific stratifications.

Choosing immunomodulating therapies for the treatment of COVID-19: recommendations based on placebo-controlled trial evidence

BACKGROUND

Immunomodulatory therapy has been extensively studied in randomized clinical trials for the treatment of patients hospitalized for COVID-19 with inconsistent findings. Guideline committees, reviewing the same clinical trial data, have generated different recommendations for immunomodulatory therapy.

OBJECTIVES

We hypothesize that trial design differences, specifically whether the study utilized an open-label or placebo-controlled design, accounted for the inconsistent mortality effects reported in clinical trials of immunomodulator therapies for COVID-19.

SOURCES

We reviewed COVID-19 treatment guidelines (World Health Organization [WHO], Infectious Diseases Society of America [IDSA] and The National Institutes of Health [NIH]) and identified the meta-analyses associated with glucocorticoids, IL-6 inhibitors, JAK kinase inhibitors, and complement C5a inhibitors that were available to the guideline authors at the time recommendations were either made or updated.

CONTENT

We identified a meta-analysis for each of the immunomodulator classes that are included in current COVID-19 treatment guidelines: glucocorticoids [WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group; Shankar-Hari M, Vale CL, Godolphin PJ, Fisher D, Higgins JPT, et al. Association between administration of IL-6 antagonists and mortality among patients hospitalized for COVID-19: A meta-analysis. JAMA. 2021;326:499-518] (cited 419), IL-6 antagonists [WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group; Shankar-Hari M, Vale CL, Godolphin PJ, Fisher D, Higgins JPT, et al. Association between administration of IL-6 antagonists and mortality among patients hospitalized for COVID-19: A meta-analysis. JAMA. 2021;326:499-518] (cited 419), JAK inhibitors [Kramer A, Prinz C, Fichtner F, Fischer AL, Thieme V, Grundeis F, et al. Janus kinase inhibitors for the treatment of COVID-19. Cochrane Database Syst Rev. 2022;6:CD015209] (cited 34), and complement C5a inhibitors [Tsai CL, Lai CC, Chen CY, Lee HS. The efficacy and safety of complement C5a inhibitors for patients with severe COVID-19: A systematic review and meta-analysis. Expert Rev Anti Infect Ther. 2023;21:77-86] (cited 1). Using the same randomized clinical trials, we evaluated the four meta-analyses accounting for trial design: placebo-controlled or open-label. Glucocorticoids (Risk Ratio [RR] 0.91 [95% CI, 0.49-1.69]), IL-6 inhibitors sarilumab (RR 1.17 [95% CI, 0.96-01.43]), and tocilizumab (RR 0.95 [95% CI, 0.76-1.19]) did not reduce mortality in placebo-controlled trials, whereas baricitinib did confer a large survival benefit (RR 0.65 [95% CI, 0.52-0.81]). The complement C5a inhibitor, vilobelimab, also reduced mortality in a single placebo-controlled trial (RR 0.76 [95% CI, 0.57-1.0]).

IMPLICATIONS

Placebo-controlled trial evidence indicates that baricitinib should be the first choice immunomodulator for patients hospitalized for COVID-19 who require any form of oxygen support-low- or high-flow oxygen, non-invasive or invasive ventilation. Vilobelimab warrants study in a large placebo-controlled trial. Treatment guidelines for future pandemics should prioritize the results of placebo-controlled trials.

Severe Legionnaires' disease

BACKGROUND

Legionnaires' disease (LD) is a common but under-diagnosed cause of community-acquired pneumonia (CAP), although rapid detection of urine antigen testing (UAT) and advances in molecular testing have improved the diagnosis. LD entails intensive care unit (ICU) admission in almost one-third of cases, and the mortality rate ranges from 4% to 40%. This review aims to discuss recent advances in the study of this condition and to provide an update on the diagnosis, pathogenesis and management of severe LD.

RESULTS

The overall incidence of LD has increased worldwide in recent years due to the higher number of patients with risk factors, especially immunosuppression, and to improvements in diagnostic methods. Although LD is responsible for only around 5% of all-cause CAP, it is one of the three most common causes of CAP requiring ICU admission. Mortality in ICU patients, immunocompromised patients or patients with a nosocomial source of LD can reach 40% despite appropriate antimicrobial therapy. Regarding pathogenesis, no Legionella-specific virulence factors have been associated with severity; however, recent reports have found high pulmonary Legionella DNA loads, and impairments in immune response and lung microbiome in the most severe cases. The clinical picture includes severe lung injury requiring respiratory and/or hemodynamic support, extrapulmonary symptoms and non-specific laboratory findings. LD diagnostic methods have improved due to the broad use of UAT and the development of molecular methods allowing the detection of all Lp serogroups. Therapy is currently based on macrolides, quinolones, or a combination of the two, with prolonged treatment in severe cases.

CONCLUSIONS

Numerous factors influence the mortality rate of LD, such as ICU admission, the underlying immune status, and the nosocomial source of the infection. The host immune response (hyperinflammation and/or immunoparalysis) may also be associated with increased severity. Given that the incidence of LD is rising, studies on specific biomarkers of severity may be of great interest. Further assessments comparing different regimens and/or evaluating host-directed therapies are nowadays needed.

Pharmacologic Treatments in Acute Respiratory Failure

Acute respiratory failure relies on supportive care using non-invasive and invasive oxygen and ventilatory support. Pharmacologic therapies for the most severe form of respiratory failure, acute respiratory distress syndrome (ARDS), are limited. This review focuses on the most promising therapies for ARDS, targeting different mechanisms that contribute to dysregulated inflammation and resultant hypoxemia. Significant heterogeneity exists within the ARDS population. Treatment requires prompt recognition of ARDS and an understanding of which patients may benefit most from specific pharmacologic interventions. The key to finding effective pharmacotherapies for ARDS may rely on deeper understanding of pathophysiology and bedside identification of ARDS subphenotypes.

Efficacy and safety of corticosteroids for the treatment of community-acquired pneumonia: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The role of corticosteroids in the treatment of community-acquired pneumonia (CAP) remains uncertain. We conducted an updated meta-analysis to investigate the effectiveness and potential effect modifiers of adjunctive corticosteroids in patients with CAP.

METHODS

The protocol of this meta-analysis was registered with PROSPERO (CRD42022354920). We searched MEDLINE, Embase, the Cochrane Library and trial registers from inception till March 2023 to identify randomized controlled trials (RCTs) investigating corticosteroids in adult patients with CAP. Our primary outcome was the risk of all-cause mortality within 30 days after randomization (if not reported at day 30, we extracted the outcome closest to 30 days). Risk ratios (RR) and mean differences (MDs) were pooled under a random-effects model.

RESULTS

Fifteen RCTs (n = 3252 patients) were included in this review. Corticosteroids reduced the risk of all-cause mortality in CAP patients (RR: 0.69, 95% CI: 0.53-0.89; high certainty). This significant result was restricted to hydrocortisone therapy and patients with severe CAP. Additionally, younger patients demonstrated a greater reduction in mortality. Corticosteroids reduced the incidence of shock and the need for mechanical ventilation (MV), and decreased the length of hospital and ICU stay (moderate certainty).

CONCLUSIONS

Corticosteroids reduce the risk of all-cause mortality, especially in younger patients receiving hydrocortisone, and probably decrease the need for MV, the incidence of shock, and the length of hospital and ICU stay in patients with CAP. Our findings indicate that patients with CAP, especially severe CAP, will benefit from adjunctive corticosteroid therapy.

Treatment Failure and Clinical Stability in Severe Community-Acquired Pneumonia

Treatment failure and clinical stability are important outcomes in community-acquired pneumonia (CAP). It is essential to know the causes and risk factors for treatment failure and delay in reaching clinical stability in CAP. The study of both as well as the associated underlying mechanisms and host response are key to improving outcomes in pneumonia.

Glucocorticoid use in acute respiratory failure from pulmonary causes and association with early changes in the systemic host immune response

BACKGROUND

Glucocorticoids are commonly used in patients with or at-risk for acute respiratory distress syndrome (ARDS), but optimal use remains unclear despite well-conducted clinical trials. We performed a secondary analysis in patients previously enrolled in the Acute Lung Injury and Biospecimen Repository at the University of Pittsburgh. The primary aim of our study was to investigate early changes in host response biomarkers in response to real-world use of glucocorticoids in patients with acute respiratory failure due to ARDS or at-risk due to a pulmonary insult. Participants had baseline plasma samples obtained on study enrollment and on follow-up 3 to 5 days later to measure markers of innate immunity (IL-6, IL-8, IL-10, TNFr1, ST2, fractalkine), epithelial injury (sRAGE), endothelial injury (angiopoietin-2), and host response to bacterial infections (procalcitonin, pentraxin-3). In our primary analyses, we investigated the effect of receiving glucocorticoids between baseline and follow-up samples on host response biomarkers measured at follow-up by doubly robust inverse probability weighting analysis. In exploratory analyses, we examined associations between glucocorticoid use and previously characterized host response subphenotypes (hyperinflammatory and hypoinflammatory).

RESULTS

67 of 148 participants (45%) received glucocorticoids between baseline and follow-up samples. Dose and type of glucocorticoids varied. Regimens that used hydrocortisone alone were most common (37%), and median daily dose was equivalent to 40 mg methylprednisolone (interquartile range: 21, 67). Participants who received glucocorticoids were more likely to be female, to be on immunosuppressive therapy at baseline, and to have higher baseline levels of ST-2, fractalkine, IL-10, pentraxin-3, sRAGE, and TNFr1. Glucocorticoid use was associated with decreases in IL-6 and increases in fractalkine. In exploratory analyses, glucocorticoid use was more frequent in participants in the hyperinflammatory subphenotype (58% vs 40%, p = 0.05), and was not associated with subphenotype classification at the follow-up time point (p = 0.16).

CONCLUSIONS

Glucocorticoid use varied in a cohort of patients with or at-risk for ARDS and was associated with early changes in the systemic host immune response.

Biological Effects of Corticosteroids on Pneumococcal Pneumonia in Mice and Humans

Background

Streptococcus pneumoniae is the most common bacterial cause of community acquired pneumonia and the acute respiratory distress syndrome (ARDS). Some clinical trials have demonstrated a beneficial effect of corticosteroid therapy in community acquired pneumonia, COVID-19, and ARDS, but the mechanisms of this benefit remain unclear. The objective of this study was to investigate the effects of corticosteroids on the pulmonary biology of pneumococcal pneumonia in an observational cohort of mechanically ventilated patients and in a mouse model of bacterial pneumonia with Streptococcus pneumoniae.

Methods

We studied gene expression with lower respiratory tract transcriptomes from a cohort of mechanically ventilated patients and in mice. We also carried out comprehensive physiologic, biochemical, and histological analyses in mice to identify the mechanisms of lung injury in Streptococcus pneumoniae with and without adjunctive steroid therapy.

Results

Transcriptomic analysis identified pleiotropic effects of steroid therapy on the lower respiratory tract in critically ill patients with pneumococcal pneumonia, findings that were reproducible in mice. In mice with pneumonia, dexamethasone in combination with ceftriaxone reduced (1) pulmonary edema formation, (2) alveolar protein permeability, (3) proinflammatory cytokine release, (4) histopathologic lung injury score, and (5) hypoxemia but did not increase bacterial burden.

Conclusions

The gene expression studies in patients and in the mice support the clinical relevance of the mouse studies, which replicate several features of pneumococcal pneumonia and steroid therapy in humans. In combination with appropriate antibiotic therapy in mice, treatment of pneumococcal pneumonia with steroid therapy reduced hypoxemia, pulmonary edema, lung permeability, and histologic criteria of lung injury, and also altered inflammatory responses at the protein and gene expression level. The results from these studies provide evidence for the mechanisms that may explain the beneficial effects of glucocorticoid therapy in patients with community acquired pneumonia from Streptococcus Pneumoniae.

Efficacy and Safety of Corticosteroid Therapy for Community-Acquired Pneumonia: A Meta-Analysis and Meta-Regression of Randomized, Controlled Trials

BACKGROUND

Community-acquired pneumonia (CAP) is associated with high morbidity and mortality. In the present study, we aimed to assess the effect of corticosteroids on all-cause mortality in patients hospitalized with CAP.

METHODS

For this meta-analysis and meta-regression, we conducted a systematic search of trials that evaluated the effect of corticosteroid therapy in patients hospitalized with CAP through March 2023. We included randomized, controlled trials, comparing adjunctive corticosteroid therapy with the standard of care alone for treatment of patients hospitalized with CAP and reporting all-cause mortality. We excluded retrospective analyses, observational data, and trial protocols. The primary outcome was all-cause mortality within 30 days after hospital admission. The safety analysis included the frequency of adverse events and steroid-associated adverse events.

RESULTS

The literature search identified 35 713 citations, of which 15 studies and 3367 patients were eligible for the final analysis. The all-cause mortality at 30 days was significantly lower in the corticosteroid group (104 of 1690, 6.15%) than in the control group (152 of 1677, 9.06%; risk ratio [RR], 0.67; 95% confidence interval [CI], .53 to .85; P = .001; I2 = 0%). In 9 studies (2549 patients) that reported the occurrence of adverse events, corticosteroid therapy was not associated with an increased risk of developing any adverse event compared with standard care (RR, 0.90; 95% CI, .65 to 1.24; P = .5; I2 = 88%).

CONCLUSIONS

Adjunctive systemic corticosteroid therapy in patients hospitalized with CAP was associated with a reduction in all-cause mortality by day 30. The benefits were more pronounced in patients with severe pneumonia.

Association between corticosteroid use and 28-day mortality in septic shock patients with gram-negative bacterial infection: a retrospective study

Purpose

Although corticosteroids are recommended in the 2021 Surviving Sepsis Campaign (SSC) guidelines, evidence with respect to their effects on short-term mortality remains conflicting. We conducted this study to identify whether corticosteroids alter 28-day mortality in septic shock patients with gram-negative bacterial infection.

Materials and methods

A total of 621 patients with septic shock and gram-negative bacterial culture results were identified from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. Propensity score matching (PSM) was performed, and Kaplan-Meier survival curve analyses with log-rank tests were used to determine the relationship between corticosteroid use and the risk of 28-day mortality. Subgroup analyses were conducted to assess whether the conclusions were stable and reliable.

Results

Corticosteroid administration was associated with increased 28-day mortality in septic shock patients with gram-negative bacterial infection (log-rank test P = 0.028). The incidence of Stage 2 or 3 AKI and the rate of hospital mortality were higher among patients who received corticosteroids. The incidence of Stage 2 or 3 AKI in the early period significantly mediated the relationship between corticosteroid use and 28-day mortality [P =0.046 for the average causal mediation effect (ACME)]. Interaction tests indicated that the effect of corticosteroid use was maintained in patients with a neutrophil-to-lymphocyte ratio (NLR) of <20 (P-value for interaction = 0.027).

Conclusion

Systemic corticosteroid use could be harmful in septic shock patients with gram-negative bacterial infection, especially in patients with relatively low NLR.

Sepsis and Adrenal Insufficiency

In sepsis, dysregulation of the hypothalamic-pituitary-adrenal axis, alterations in cortisol metabolism, and tissue resistance to glucocorticoids can all result in relative adrenal insufficiency or critical illness-related corticosteroid insufficiency (CIRCI). The symptoms and signs of CIRCI during sepsis are nonspecific, generally including decreased mental status, unexplained fever, or hypotension refractory to fluids, and the requirement of vasopressor therapy to maintain adequate blood pressure. While we have been aware of this syndrome for over a decade, it remains a poorly understood condition, challenging to diagnose, and associated with significantly diverging practices among clinicians, particularly regarding the optimal dosing and duration of corticosteroid therapy. The existing literature on corticosteroid use in patients with sepsis and septic shock is vast with dozens of randomized controlled trials conducted across the past 4 decades. These studies have universally demonstrated reduced duration of shock, though the effects of corticosteroids on mortality have been inconsistent, and their use has been associated with adverse effects including hyperglycemia, neuromuscular weakness, and an increased risk of infection. In this article, we aim to provide a thorough, evidence-based, and practical review of the current recommendations for the diagnosis and management of patients with sepsis who develop CIRCI, explore the controversies surrounding this topic, and highlight what lies on the horizon as new evidence continues to shape our practice.

Severe community-acquired pneumonia in the post COVID-19 era

PURPOSE OF REVIEW

The aim was to examine and summarize the most recent published literature in the last years stating the advances for treatment options and adjunctive therapies in patients hospitalized with severe community-acquired pneumonia (sCAP). Search was performed in PubMed, including observational studies, randomized controlled trials, systematic reviews and meta-analyses, and international guidelines.

RECENT FINDINGS

Regardless of a large number of published CAP guidelines, most of their recommendations are based on low-level evidence.Viruses have an increasing role as sCAP etiology with an impact on mortality. Accordingly, it is imperative to strengthen the demand for vaccines and newer antivirals. Considering an early monitoring of the immune response in patients with severe Influenza, may help to evaluate a personalized immunomodulatory strategy. Despite growing evidence, the use of corticosteroids as an adjunctive therapy in bacterial sCAP continues to be controversial.

SUMMARY

Mortality due to sCAP still remains undesirably high. This fact strengthens the need for more high-quality research to increase evidence. It also highlights the need for clinicians to be aware of the level of evidence of the stated recommendations, taking this into consideration before decision making.

Corticosteroids in Community-Acquired Bacterial Pneumonia: a Systematic Review, Pairwise and Dose-Response Meta-Analysis

INTRODUCTION

International guidelines provide heterogenous guidance on use of corticosteroids for community-acquired pneumonia (CAP).

METHODS

We performed a systematic review of randomized controlled trials examining corticosteroids in hospitalized adult patients with suspected or probable CAP. We performed a pairwise and dose-response meta-analysis using the restricted maximum likelihood (REML) heterogeneity estimator. We assessed the certainty of the evidence using GRADE methodology and the credibility of subgroups using the ICEMAN tool.

RESULTS

We identified 18 eligible studies that included 4661 patients. Corticosteroids probably reduce mortality in more severe CAP (RR 0.62 [95% CI 0.45 to 0.85]; moderate certainty) with possibly no effect in less severe CAP (RR 1.08 [95% CI 0.83 to 1.42]; low certainty). We found a non-linear dose-response relationship between corticosteroids and mortality, suggesting an optimal dose of approximately 6 mg of dexamethasone (or equivalent) for a duration of therapy of 7 days (RR 0.44 [95% 0.30 to 0.66]). Corticosteroids probably reduce the risk of requiring invasive mechanical ventilation (RR 0.56 [95% CI 0.42 to 74] and probably reduce intensive care unit (ICU) admission (RR 0.65 [95% CI 0.43 to 0.97]) (both moderate certainty). Corticosteroids may reduce the duration of hospitalization and ICU stay (both low certainty). Corticosteroids may increase the risk of hyperglycemia (RR 1.76 [95% CI 1.46 to 2.14]) (low certainty).

CONCLUSION

Moderate certainty evidence indicates that corticosteroids reduce mortality in patients with more severe CAP, the need for invasive mechanical ventilation, and ICU admission.

The influence of steroid type on outcomes in patients with acute respiratory distress syndrome

BACKGROUND

Recent systematic reviews and meta-analyses have suggested that low-dose steroids are effective in the treatment of acute respiratory distress syndrome (ARDS). Recent guidelines recommend the use of low-dose steroids instead of high-dose steroids. These systematic reviews were conducted based on the concept that the effect of steroids is constant regardless of their type. We discuss whether the type of steroid used influences the outcomes in patients with ARDS.

MAIN BODY

From a pharmacological standpoint, methylprednisolone has little activity as a mineralocorticoid and may cause pulmonary hypertension. The results of the rank probability of our previous network meta-analysis revealed that low-dose methylprednisolone might be an optimal treatment compared to using other types of steroids or no steroids in terms of ventilator-free days. Similarly, an analysis of individual data from four randomized controlled trials suggested that low-dose methylprednisolone was associated with decreased mortality in patients with ARDS. Dexamethasone has attracted the attention of clinicians as a novel adjunct therapy for ARDS.

CONCLUSION

Recent evidence has shown that low-dose methylprednisolone may be an effective treatment option for ARDS. The timing of initiation and duration of low-dose methylprednisolone therapy should be verified in future studies.

Efficacy and safety of adjunctive corticosteroids in the treatment of severe community-acquired pneumonia: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

This systematic review and meta-analysis aimed to investigate the clinical efficacy and safety of systemic corticosteroids in the treatment of patients with severe community-acquired pneumonia (sCAP).

METHODS

A comprehensive search was conducted using the Medline, Embase, ClinicalTrials.gov, and Scopus databases for articles published until April 24, 2023. Only randomized controlled trials (RCTs) that assessed the clinical efficacy and safety of adjunctive corticosteroids for treating sCAP were included. The primary outcome was the 30-day all-cause mortality.

RESULTS

A total of severe RCTs involving 1689 patients were included in this study. Overall, the study group had a lower mortality rate at day 30 than the control group (risk ratio [RR], 0.61; 95% CI 0.44 to 0.85; p < 0.01) with low heterogeneity (I2 = 0%, p = 0.42). Compared to the control group, the study group had a lower risk of the requirement of mechanical ventilation (RR 0.57; 95% CI 0.45 to 0.73; p < 0.001), shorter length of intensive care unit (MD - 0.8; 95% CI - 1.4 to - 0.1; p = 0.02), and hospital stay (MD - 1.1; 95% CI - 2.0 to - 0.1; p = 0.04). Finally, no significant difference was observed between the study and the control groups in terms of gastrointestinal tract bleeding (RR 1.03; 95% CI 0.49 to 2.18; p = 0.93), healthcare-associated infection (RR 0.89; 95% CI 0.60 to 1.32; p = 0.56), and acute kidney injury (RR 0.68; 95% CI 0.21 to 2.26; p = 0.53).

CONCLUSIONS

In patients with sCAP, adjunctive corticosteroids can provide survival benefits and improve clinical outcomes without increasing adverse events. However, because the pooled evidence remains inconclusive, further studies are required.

Interventions to improve outcomes in community-acquired pneumonia

INTRODUCTION

Community-acquired pneumonia (CAP) is a common infection associated with high morbimortality and a highly deleterious impact on patients' quality of life and functionality. We comprehensively review the factors related to the host, the causative microorganism, the therapeutic approach and the organization of health systems (e.g. setting for care and systems for allocation) that might have an impact on CAP-associated outcomes. Our main aims are to discuss the most controversial points and to provide some recommendations that may guide further research and the management of patients with CAP, in order to improve their outcomes, beyond mortality.

AREA COVERED

In this review, we aim to provide a critical account of potential measures to improve outcomes of CAP and the supporting evidence from observational studies and clinical trials.

EXPERT OPINION

CAP is associated with high mortality and a highly deleterious impact on patients' quality of life. To improve CAP-associated outcomes, it is important to understand the factors related to the patient, etiology, therapeutics, and the organization of health systems.