Procalcitonin kinetics within the first days of sepsis: relationship with the appropriateness of antibiotic therapy and the outcome

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2024

The 2024 revised edition of the Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock (J-SSCG 2024) is published by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine. This is the fourth revision since the first edition was published in 2012. The purpose of the guidelines is to assist healthcare providers in making appropriate decisions in the treatment of sepsis and septic shock, leading to improved patient outcomes. We aimed to create guidelines that are easy to understand and use for physicians who recognize sepsis and provide initial management, specialized physicians who take over the treatment, and multidisciplinary healthcare providers, including nurses, physical therapists, clinical engineers, and pharmacists. The J-SSCG 2024 covers the following nine areas: diagnosis of sepsis and source control, antimicrobial therapy, initial resuscitation, blood purification, disseminated intravascular coagulation, adjunctive therapy, post-intensive care syndrome, patient and family care, and pediatrics. In these areas, we extracted 78 important clinical issues. The GRADE (Grading of Recommendations Assessment, Development and Evaluation) method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members. As a result, 42 GRADE-based recommendations, 7 good practice statements, and 22 information-to-background questions were created as responses to clinical questions. We also described 12 future research questions.

IL-6 Baseline Values and Dynamic Changes in Predicting Sepsis Mortality: A Systematic Review and Meta-Analysis

Sepsis, a life-threatening condition arising from a dysregulated immune response to infection, is a significant health burden globally. Interleukin-6 (IL-6), an inflammatory cytokine produced by immune cells as a response to infection and tissue damage, plays a key role in the pathogenesis of sepsis. This systematic review and meta-analysis aimed to investigate the association of the baseline plasma levels of IL-6, and the dynamic change in these levels over a timespan of 96 h, with short-term mortality. A systematic literature search was conducted across multiple databases. Studies were included if they assessed the independent prognostic value of IL-6 in adult sepsis patients, used well-defined sepsis criteria, and reported at least one IL-6 measurement. Pooled effect estimates for the association between IL-6 and 28-30-day mortality were determined using logistic regression and AUROC analysis. Thirty-one studies, encompassing 4566 patients, were included. While baseline IL-6 levels and 96 h IL-6 clearance were not significantly associated with mortality risk (pooled OR 1.001, 95% CI 0.999-1.003 and 1.019, 95% CI 0.925-1.112, respectively), AUROC analysis indicated moderate-to-good discriminatory power for both baseline (0.701, 95% CI 0.660-0.742) and 96 h IL-6 clearance (0.828, 95% CI 0.736-0.919) in predicting 28-day mortality. While not a strong independent predictor, IL-6 demonstrates some discriminatory ability, suggesting its potential value in conjunction with other biomarkers.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2024

The 2024 revised edition of the Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock (J-SSCG 2024) is published by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine. This is the fourth revision since the first edition was published in 2012. The purpose of the guidelines is to assist healthcare providers in making appropriate decisions in the treatment of sepsis and septic shock, leading to improved patient outcomes. We aimed to create guidelines that are easy to understand and use for physicians who recognize sepsis and provide initial management, specialized physicians who take over the treatment, and multidisciplinary healthcare providers, including nurses, physical therapists, clinical engineers, and pharmacists. The J-SSCG 2024 covers the following nine areas: diagnosis of sepsis and source control, antimicrobial therapy, initial resuscitation, blood purification, disseminated intravascular coagulation, adjunctive therapy, post-intensive care syndrome, patient and family care, and pediatrics. In these areas, we extracted 78 important clinical issues. The GRADE (Grading of Recommendations Assessment, Development and Evaluation) method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members. As a result, 42 GRADE-based recommendations, 7 good practice statements, and 22 information-to-background questions were created as responses to clinical questions. We also described 12 future research questions.

Benefits and Harms of Procalcitonin- or C-Reactive Protein-Guided Antimicrobial Discontinuation in Critically Ill Adults With Sepsis: A Systematic Review and Network Meta-Analysis

OBJECTIVES

In sepsis treatment, antibiotics are crucial, but overuse risks development of antibiotic resistance. Recent guidelines recommended the use of procalcitonin to guide antibiotic cessation, but solid evidence is insufficient. Recently, concerns were raised that this strategy would increase recurrence. Additionally, optimal protocol or difference from the commonly used C-reactive protein (CRP) are uncertain. We aimed to compare the effectiveness and safety of procalcitonin- or CRP-guided antibiotic cessation strategies with standard of care in sepsis.

DATA SOURCES

A systematic search of PubMed, Embase, CENTRAL, Igaku Chuo Zasshi, ClinicalTrials.gov , and World Health Organization International Clinical Trials Platform.

STUDY SELECTION

Randomized controlled trials involving adults with sepsis in intensive care.

DATA EXTRACTION

A systematic review with network meta-analyses was performed. The Grading of Recommendations, Assessments, Developments, and Evaluation method was used to assess certainty.

DATA SYNTHESIS

Eighteen studies involving 5023 participants were included. Procalcitonin-guided and CRP-guided strategies shortened antibiotic treatment (-1.89 days [95% CI, -2.30 to -1.47], -2.56 days [95% CI, -4.21 to -0.91]) with low- to moderate-certainty evidence. In procalcitonin-guided strategies, this benefit was consistent even in subsets with shorter baseline antimicrobial duration (7-10 d) or in Sepsis-3, and more pronounced in procalcitonin cutoff of "0.5 μg/L and 80% reduction." No benefit was observed when monitoring frequency was less than half of the initial 10 days. Procalcitonin-guided strategies lowered mortality (-27 per 1000 participants [95% CI, -45 to -7]) and this was pronounced in Sepsis-3, but CRP-guided strategies led to no difference in mortality. Recurrence did not increase significantly with either strategy (very low to low certainty).

CONCLUSIONS

In sepsis, procalcitonin- or CRP-guided antibiotic discontinuation strategies may be beneficial and safe. In particular, the usefulness of procalcitonin guidance for current Sepsis-3, where antimicrobials are used for more than 7 days, was supported. Well-designed studies are needed focusing on monitoring protocol and recurrence.

Predicting Mortality in Sepsis: The Role of Dynamic Biomarker Changes and Clinical Scores-A Retrospective Cohort Study

BACKGROUND

The prognostic value of baseline inflammatory markers in sepsis remains controversial, with conflicting evidence regarding their association with mortality. The dynamic changes in these markers over time might offer additional insights into disease progression and patient outcomes.

METHODS

This retrospective observational study included 138 patients with severe infections. The inflammatory biomarkers procalcitonin (PCT), C-reactive protein (CRP), and lactate (LAC) were measured at three time points: upon hospital admission (baseline), approximately 24-48 h after admission (second measurement; M2), and 48-72 h after admission (third measurement; M3). The primary outcome was 30-day mortality. A Mann-Whitney U test was used to compare the biomarker levels between the survivors and non-survivors. A Spearman's correlation was used to assess the relationships between the baseline parameters. A logistic regression and a receiver operating characteristic (ROC) curve analysis were employed to evaluate the prognostic value of the baseline markers and their dynamic changes.

RESULTS

The baseline LAC and SOFA score were significantly associated with 30-day mortality. The percentage decrease in PCT, CRP, and LAC from the baseline to M3 emerged as strong predictors of survival, with the ROC curve analysis demonstrating superior discriminatory ability compared to the baseline values. CRP_Delta exhibited the highest AUC (0.903), followed by PCT_Delta (0.843) and LAC_Delta (0.703).

CONCLUSIONS

The dynamic changes in these inflammatory biomarkers, particularly PCT, CRP, and LAC, offer valuable prognostic information beyond their baseline levels in predicting 30-day mortality in severe infections. These findings highlight the importance of monitoring biomarker trends for early risk stratification and potential treatment guidance.

Assessment value of interleukin-6, procalcitonin, and C-reactive protein early kinetics for initial antibiotic efficacy in patients with febrile neutropenia: A prospective study

BACKGROUND

This study aims to investigate the early kinetics of interleukin 6 (IL-6), procalcitonin (PCT), and C-reactive protein (CRP) on initial antibiotic efficacy in hematological disorder patients with febrile neutropenia (FN).

METHODS

A total of 40 patients with 43 episodes of FN were enrolled and divided into initial antibiotic effective group (IAE group, n = 24) and initial antibiotic ineffective group (IAI group, n = 19). The levels of IL-6, PCT, and CRP before antibacterial treatment (T0), and 12 h (T1), 24 h (T2), 48 h (T3), and 72 h (T4) post-antibacterial treatment were determined, respectively. Furthermore, the receiver operating characteristic curve (ROC) analysis was performed to evaluate the clinical value of indicators.

RESULTS

In IAE group, the IL-6 levels gradually decreased from T0 to T4, and the CRP levels significantly decreased at 48 to 72 h, whereas both IL-6 and CRP remained at high levels in the IAI group. The PCT levels in both groups increased at the early stage of anti-infection (T1-T2) and reached to peak at T1-T2 in effective group. ROC curve analysis identified IL-6 as a predictive biomarker for initial antibiotic efficacy at 12, 48, and 72 h after treatment, with the AUC of 0.698, 0.744, and 0.821, respectively. In addition, CRP demonstrated predictive ability of initial antibiotics against infection at 24, 48, and 72 h after therapy, with the AUC of 0.724, 0.741, and 0.797, respectively. ROC curve analysis of percentage changes demonstrated that IL-6 percentage change showed predictive ability of antibiotic efficacy at the early stage, and both the IL-6 and CRP percentage changes showed the predictive ability of antibiotic efficacy 48 or 72 h after antibiotics therapy.

CONCLUSION

This study confirmed IL-6 and CRP levels, and the percentage change in IL-6 as the biomarkers for initial antibiotic efficacy prediction in hematological disorder patients with FN.

Real-life Data on Cefiderocol Efficacy and Safety to Treat Multidrug-Resistant Acinetobacter baumannii Infections

Background

The objective of this study was to expand real-life data on cefiderocol efficacy to treat multidrug-resistant Acinetobacter baumannii infections.

Methods

This was a retrospective monocentric study including patients hospitalized (>24 hours) at Policlinico Tor Vergata, Rome, Italy, between May 1, 2021, and September 1, 2022, treated with cefiderocol (>48 hours). The primary objective was early clinical improvement at 48-72 hours from cefiderocol start; secondary objectives were clinical success (composite outcome of infection resolution and 14-day survival), breakthrough infection, overall 30-day mortality, and cefiderocol-related adverse events.

Results

Eleven patients were enrolled; 91% males (10/11), with a median age (interquartile range [IQR]) of 69 (59-71) years, 91% had ≥1 comorbidity, and 72.7% (8/11) were hospitalized in internal medicine wards. Six patients with bloodstream infection (54.5%; 4 primary, 2 central line-associated), 2 with pneumonia (18.2%), 2 with urinary tract infections (18.2%), and 1 with intra-abdominal infection (9.1%) were treated. Four patients (36.3%) presented with septic shock at cefiderocol start. Cefiderocol was used as monotherapy in 3/11 patients (27.3%), was combined with colistin in all the other 8 cases, and was used in triple combination with tigecycline in 2 patients. The median duration of treatment (IQR) was 12 (10-14) days. Early clinical improvement was documented in 8/11 patients (72.7%), clinical success in 8/11 patients (72.7%). Overall 30-day mortality was 27.3% (3/11), with death occurring a median (IQR) of 19 (17.5-20.5) days after the start of therapy. No cefiderocol-related adverse events were documented.

Conclusions

Cefiderocol seems to be a safe and effective option for multidrug-resistant Acinetobacter baumannii infections.

Association between timing and adequacy of antibiotics and adverse outcomes in patients with sepsis and septic shock: A multicentre retrospective cohort study

OBJECTIVES

To investigate the association between the timing and adequacy of antibiotics administered to patients presenting with culture-positive sepsis and septic shock to the ED and in-hospital mortality and/or intensive care unit (ICU) admission.

METHODS

Multicentre retrospective cohort study of ED presentations at four metropolitan hospitals in Sydney, Australia between January 2017 and November 2019. Encounters for patients aged ≥16 years meeting specified criteria for sepsis or septic shock with antibiotic administration within the first 6 h of presentation were included.

RESULTS

Of 7611 encounters included in the study, 2328 (31%) were culture positive, and 2228 (29%) met the criteria for septic shock. In culture-positive sepsis encounters, partial or inadequate antibiotic coverage was associated with higher risk of death or ICU admission (adjusted odds ratio [AOR] 1.50, 95% confidence interval [CI] 1.04-2.06 and 1.95, 95% CI 1.28-2.99, respectively). This effect was not significant in septic shock encounters (AOR 1.10, 95% CI 0.64-1.88) with partial coverage and (AOR 1.63, 95% CI 0.81-3.3) inadequate coverage. Time to antibiotics was not significantly associated with the risk of mortality/ICU admission. This inference remained the same when analysis was restricted to cases with adequate antibiotic coverage.

CONCLUSIONS

In a large multicentre sample of patients with culture-positive sepsis, inadequacy of antibiotics was associated with higher risk of in-hospital mortality or ICU admission.

Use of biomarkers to individualize antimicrobial therapy duration: a narrative review

BACKGROUND

Reducing the overuse of antimicrobials is imperative for the sake of minimizing antimicrobial-associated adverse effects, optimizing resource utilization, and curtailing the rise in multidrug-resistant organisms. Biomarkers reflect the host responses to infection and may assist with minimizing unnecessary antimicrobial usage.

OBJECTIVES

To review the literature pertaining to the performance of biomarkers specifically used to guide the duration of antimicrobial therapy (AMT).

SOURCES

Randomized controlled trials, observational studies, and meta-analyses assessing biomarker-guided approaches to AMT decision-making and their impact on the duration of therapy were reviewed.

CONTENT

Several randomized controlled trials and real-world observational studies have shown that a procalcitonin (PCT)-guided strategy can help clinicians individualize the duration of AMT, particularly among non-critically ill patients hospitalized with suspected respiratory tract infections when using a PCT cut-off value of <0.25 μg/L and critically ill patients with respiratory tract infections or undifferentiated sepsis when using a PCT cut-off value of <0.5 μg/L or ≥80% decline in the peak level. C-reactive protein is a non-specific marker of inflammation that may also assist with an early discontinuation of AMT; however, data are limited. Haematological biomarkers are prone to variance between individuals and are often influenced by medications and non-infectious conditions, making them less reliable for the purposes of AMT decision-making. Novel biomarkers such as multi-protein signatures and host gene expression tests have shown promise as tools to better differentiate between bacterial and non-bacterial infections; clinical studies are needed to determine whether they can be used to help optimize the duration of AMT.

IMPLICATIONS

Studies have demonstrated that a PCT-guided strategy, when utilized appropriately, can help guide clinicians to individualize and often reduce the duration of AMT, especially in patients hospitalized with respiratory tract infections and those admitted to the intensive care unit with suspected respiratory tract infections or sepsis. The impact of utilizing other biomarkers is less clear and requires further study.

Respiratory Immune Responses during Infection and Pollution Inhalation

The COVID-19 pandemic highlighted the importance of lung immune responses to pathogens and environmental factors [...].

Changes in Heparin-Binding Protein, Procalcitonin, and C-Reactive Protein Within the First 72 Hours Predict 28-Day Mortality in Patients Admitted to the Intensive Care Unit with Septic Shock

BACKGROUND This study aimed to evaluate the possible associations of heparin-binding protein (HBP), procalcitonin (PCT), and C-reactive protein (CRP) levels with 28-day mortality in septic shock patients admitted to Intensive Care Units (ICUs). MATERIAL AND METHODS Blood samples were taken at ICU admission and measured again 72 h later to calculate changes in HBP (ΔHBP), changes in PCT (ΔPCT), changes in CRP (ΔCRP), and changes in Sequential Organ Failure Assessment (DSOFA) relative to baseline. RESULTS Variables included in the univariable logistic regression model for survival were age, Acute Physiology and Chronic Health Evaluation (APACHE) II scores, decreasing ΔSOFA, decreasing DHBP, decreasing ΔPCT, and decreasing ΔCRP. Survival was directly related to decreasing ΔHBP with odds ratio (OR)=9.95 (95% confidence interval [CI] 4.63 to 21.35; P<0.001), decreasing ΔPCT with OR=7.85 (3.74 to 16.49; P<0.001), decreasing ΔCRP with OR=5.83 (2.84 to 11.97; P<0.001), decreasing ΔSOFA with OR=1.93 (1.00 to 3.75; P=0.051) and APACHE II score with OR=1.93 (1.14 to 1.68; P=0.001). In a multivariable logistic regression model for survival, only decreasing DHBP with OR=7.18 (2.91 to 17.69; P<0.001), decreasing ΔPCT with OR=5.17 (2.12 to 12.56; P<0.001), and decreasing ΔCRP with OR=4.33 (1.77 to 10.61; P=0.001) remained significant. CONCLUSIONS Measuring changes in HBP, PCT, and CRP within 72 h of admission may aid in predicting 28-day mortality for patients with septic shock in ICUs.

Implementation of Procalcitonin in Antibiotic Stewardship: Derivation of a Consensus Algorithm for Procalcitonin Use in Clinical Practice

Reducing antibiotics overuse is essential to minimize antibiotics related side effects and to prevent the emergence of multidrug-resistant bacteria. Procalcitonin (PCT) guided antibiotics therapy has been reported to be safe in patients with acute respiratory infections and sepsis, improving clinical outcomes as well as reducing the duration of antibiotics use. However, there is still no universal agreement on clinical guidelines in Korea for optimal PCT applications. Through this expert consensus meeting, clinical research findings in the PCT-guided antibiotics treatment interventions and real-world clinical applications were discussed. From the perspective of antibiotic stewardship, PCT application target groups, cut-offs, and testing cycles were discussed to reach a consensus on the PCT-guided antibiotics treatment algorithm for application in Korea. Combining clinical assessment for patients with an appropriate PCT-guided antibiotics treatment algorithm could improve the diagnosis and treatment of acute respiratory infections and sepsis. In addition, continuous education and regular feedback would improve the effectiveness of antibiotic stewardship.

Nanotechnological interventions of the microbiome as a next-generation antimicrobial therapy

The rise of antimicrobial resistance (AMR) impacts public health due to the diminished potency of existing antibiotics. The microbiome plays an important role in the host's immune system activity and shows the history of exposure to antimicrobials and its manipulation in combating antimicrobial resistance. Advancements in gene technologies, DNA sequencing, and computational biology have emerged as powerful platforms to better understand the relationship between animals and microorganisms (MOs). The past few years have witnessed an increase in the use of nanotechnology, both in industry and in academia, as tools to tackle antimicrobial resistance. New strategies of microbiome manipulation have been developed, such as the use of prebiotics, probiotics, peptides, antibodies, an appropriate diet, phage therapy, and the use of various nanotechnological techniques. Owing to the research outcomes, targeted delivery of antimicrobials with some modifications with nanoparticles can lead to the destruction of resistant microbial cells. In addition, nanoparticles have been studied for their potential antimicrobial effects both in vitro and in vivo. In this review, we highlight key opportunistic areas for applying nanotechnologies with the aim of manipulating the microbiome for the treatment of antimicrobial resistance. Besides providing a detailed review on various nanomaterials, technologies, opportunities, technical needs, and potential approaches for the manipulation of the microbiome to address these challenges, we discuss future challenges and our perspective.

A cytokine panel and procalcitonin in COVID-19, a comparison between intensive care and non-intensive care patients

OBJECTIVES

Procalcitonin (PCT) is an acute-phase reactant with concentrations ≥0.5 μg/L indicative of possible bacterial infection in patients with SARS-CoV-2 infection (COVID-19). Some with severe COVID-19 develop cytokine storm secondary to virally driven hyper-inflammation. However, increased pro-inflammatory cytokines are also seen in bacterial sepsis. This study aimed to assess the clinical utility of a cytokine panel in the assessment of COVID-19 with bacterial superinfections along with PCT and C-reactive protein (CRP).

METHODS

The retrospective analysis included serum cytokines (interleukins; IL-1β, IL-6, IL-8 and tumour necrosis factor (TNFα)) measured using Ella™ (Bio-Techne, Oxford, UK) and PCT measured by Roche Cobas (Burgess Hill, UK) in patients admitted with COVID-19 between March 2020 and January 2021. Patients enrolled into COVID-19 clinical trials, treated with Remdesivir/IL-6 inhibitors were excluded. The cytokine data was compared between intensive care unit (ICU) patients, age matched non-ICU patients and healthy volunteers as well as ICU patients with high and normal PCT (≥0.5 vs. <0.5 μg/L).

RESULTS

Cytokine concentrations and CRP were higher in COVID-19 patients (76; ICU & non-ICU) vs. healthy controls (n = 24), all p<0.0001. IL-6, IL-8, TNFα and were higher in ICU patients (n = 46) vs. non-ICU patients (n = 30) despite similar CRP. Among 46 ICU patients, the high PCT group (n = 26) had higher TNFα (p<0.01) and longer ICU stay (mean 47 vs. 25 days, p<0.05). There was no difference in CRP and blood/respiratory culture results between the groups.

CONCLUSIONS

Pro-inflammatory cytokines and PCT were higher in COVID-19 patients requiring ICU admission vs. non-ICU admissions despite no difference in CRP. Furthermore, TNFα was higher in those with high PCT and requiring longer ICU admission despite no difference in CRP or rate of bacterial superinfection.

Combined Use of Presepsin and (1,3)-β-D-glucan as Biomarkers for Diagnosing Candida Sepsis and Monitoring the Effectiveness of Treatment in Critically Ill Patients

New biomarker panel was developed and validated on 165 critically ill adult patients to enable a more accurate invasive candidiasis (IC) diagnosis. Serum levels of the panfungal biomarker (1,3)-β-D-glucan (BDG) and the inflammatory biomarkers C-reactive protein, presepsin (PSEP), and procalcitonin (PCT) were correlated with culture-confirmed candidemia or bacteremia in 58 and 107 patients, respectively. The diagnostic utility was evaluated in sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). BDG was the best marker for IC, achieving 96.6% sensitivity, 97.2% specificity, 94.9% PPV, and 98.1% NPV at a cut-off of 200 pg/mL (p ≤ 0.001). PSEP exhibited 100% sensitivity and 100% NPV at a cut-off of 700 pg/mL but had a lower PPV (36.5%) and low specificity (5.6%). Combined use of PSEP and BDG, thus, seems to be the most powerful laboratory approach for diagnosing IC. Furthermore, PSEP was more accurate for 28-day mortality prediction the area under the receiver operating characteristic curve (AUC = 0.74) than PCT (AUC = 0.31; PCT cut-off = 0.5 ng/mL). Finally, serum PSEP levels decreased significantly after only 14 days of echinocandin therapy (p = 0.0012). The probability of IC is almost 100% in critically ill adults with serum BDG and PSEP concentrations > 200 pg/mL and >700 pg/mL, respectively, defining a borderline between non-invasive superficial Candida colonization and IC.

Serum markers for the early diagnosis of intestinal anastomotic leak after gyne-oncological operations

OBJECTIVE

To analyse the serum markers for the early diagnosis of intestinal anastomotic leak (AL) after the gyne-oncological operations.

METHODS

Between September 2017 and March 2021, patients with an intestinal anastomosis performed during the gyne-oncological surgeries were identified from a tertiary centre in Turkey. As the local guideline of the clinic, all these patients were followed by measuring serum samples including procalcitonin (PCT) and C-reactive protein (CRP) on postoperative day (POD) 1 through the day of discharge or the day of re-operation for AL.

RESULTS

12.5% (5/40) of the patients suffered an AL and 4 of them were re-operated. The mean albumin values on POD 3-4 and the mean platelet values on POD 1 were lower in the AL group (P < .05). Although it was not statistically significant (P > .05), median PCT values (ng/mL) on POD 8-10 were higher in the AL group compared with no leak group. The best cut-off point for PCT on POD 9 was determined to be 0.11 ng/mL (AUC: 0.917, Sensitivity = 100.0%, specificity = 66.7%, positive predictive value = 66.7%, negative predictive value = 100.0%).

CONCLUSION

Serum PCT and CRP concentrations were not found to be helpful for the early diagnosis of AL in patients operated for gyne-oncological malignancies. Low levels of albumin and platelets in the first days after the operation may be clue for a possible AL.

Role of Procalcitonin in the Prognosis of Mortality in Patients Admitted to the Intensive Care Unit: A Review Study

Background

This review study aimed to investigate the role of PCT in the prognosis of mortality among patients admitted to the intensive care units (ICU). Procalcitonin (PCT) is a polypeptide and prohormone of calcitonin. This prohormone is secreted by thyroid gland C cells in response to hypercalcemia, and Its elevated level indicates infection, especially bacterial infections, in which there is a systematic response to infection.

Materials and Methods

This narrative review study was performed based on Cochrane collaboration recommendations for reviews. We reviewed all the titles and abstracts of published research articles with the following inclusion criteria studies aimed to confirm the function of a prognostic model in predicting mortality or survival, (b) mortality or survival of a specific endpoint (for example, 30 days), (c) patients admitted to intensive care units, and d) the articles written in English. The exclusion criteria of the current review included: (a) articles whose data were not specifically focused on prognosis of patients in ICU, (b) articles that did not provide sufficient information on the cause of death of patients in ICU, and (c) articles focusing on the treatment of comorbid patients with infections in ICU. The search was conducted on Google Scholar, PubMed, Magiran, ScienceDirect, and SID. Also, to search Iranian databases, including SID and Magiran, the same terms and expressions were searched.

Results

Based on the findings of this review, serum levels of PCT were reported within the range of at least 5 to more than 16 ng/ml in patients admitted to ICU. The mortality rate was estimated at 5.7% to 79% in these patients. Moreover, the incidence of sepsis was reported from 13% to 77.6%.

Conclusion

Serum levels of PCT as a prognostic factor may help early detection, and better classification of the poor prognoses sepsis patients and more invasive treatment of patients admitted to ICU and are at risk for mortality.

Prognostic Value of Procalcitonin and C-Reactive Protein in 1608 Critically Ill Patients with Severe Influenza Pneumonia

Background: Procalcitonin (PCT) and C-Reactive protein (CRP) are well-established sepsis biomarkers. The association of baseline PCT levels and mortality in pneumonia remains unclear, and we still do not know whether biomarkers levels could be related to the causative microorganism (GPC, GNB). The objective of this study is to address these issues. Methods: a retrospective observational cohort study was conducted in 184 Spanish ICUs (2009–2018). Results: 1608 patients with severe influenza pneumonia with PCT and CRP available levels on admission were included, 1186 with primary viral pneumonia (PVP) and 422 with bacterial Co-infection (BC). Those with BC presented higher PCT levels (4.25 [0.6–19.5] versus 0.6 [0.2–2.3]ng/mL) and CRP (36.7 [20.23–118] versus 28.05 [13.3–109]mg/dL) as compared to PVP (p < 0.001). Deceased patients had higher PCT (ng/mL) when compared with survivors, in PVP (0.82 [0.3–2.8]) versus 0.53 [0.19–2.1], p = 0.001) and BC (6.9 [0.93–28.5] versus 3.8 [0.5–17.37], p = 0.039). However, no significant association with mortality was observed in the multivariate analysis. The PCT levels (ng/mL) were significantly higher in polymicrobial infection (8.4) and GPC (6.9) when compared with GNB (1.2) and Aspergillus (1.7). The AUC-ROC of PCT for GPC was 0.67 and 0.32 for GNB. The AUROC of CRP was 0.56 for GPC and 0.39 for GNB. Conclusions: a single PCT/CRP value at ICU admission was not associated with mortality in severe influenza pneumonia. None of the biomarkers have enough discriminatory power to be used for predicting the causative microorganism of the co-infection.

Neglected Variables in the Interpretation of Serum Procalcitonin Levels in Patients With Septic Shock

The interpretation of serum procalcitonin (PCT) levels in septic patients is facilitated by reviewing the known stimuli that activate the PCT family of genes. Herein we describe 7 pathways that, alone or in combination, can increase serum PCT levels. As a marker of activation of innate immunity, high PCT levels affect clinical diagnosis, can be trended as a measure of "source" control, and can guide duration of antibacterial therapy in septic patients. Low PCT levels reflect little to no activation of an innate immune response, influence the differential diagnosis, and support the discontinuation of empiric antibiotic therapy. Understanding the pathways that result in elevated serum PCT levels is necessary for interpretation and subsequent clinical management.

Early procalcitonin determination in the emergency department and clinical outcome of community-acquired pneumonia in old and oldest old patients

We evaluated patients admitted through our ED for community-acquired pneumonia (CAP) to assess the relevance of an early procalcitonin (PCT) determination on patient's outcomes.

METHODS

We reviewed all patients admitted for CAP in a 10 years period (2008-2017). Patients were stratified according to age groups: (18-65 years; 65-84 years; and ≥85 years), CURB-65 score, need for ventilation, Sepsis-3 criteria at admission, enrollment period, blood culture in ED. In-hospital mortality rate and length of hospital stay (LOS) were compared between patients that had an early PCT determination in ED vs. patients admitted without.

RESULTS

Our study cohort consisted of 4056 CAP patients, age 76 [IQ range 64-84] years. We enrolled 1039 patients <65 years old, 2015 aged 65-84 years, and 1002 aged ≥85 years. Overall, the early PCT determination in ED was not associated to a reduced LOS (p=0.630), nor to a reduced mortality rate (p=0.134). However, in patients ≥ 85 years, the PCT determination in ED was associated with lower mortality in those with CURB-65 ≥ 2, and Charlson's score ≥ 2 (p=0.033 and p=0.002, respectively).

CONCLUSIONS

Although an early PCT assessment in ED was not associated with better outcomes in term of LOS and mortality in patients with CAP, our findings suggest that it might be associated with reduced mortality in patients ≥ 85 years with severe CAP or high comorbidity.

Review Article: Presepsin: New Biomaker to Evaluate Empirical Antibiotic Therapy Outcome in Septic Condition

This review presents key publications from the research field of new biomarker of sepsis and other relevant journals during 2009-2015. The results of these experimental studies and clinical trials are discussed in the context of biomarker for sepsis and the accuracy of presepsin for optimising antibiotic therapy. The discussion highlights and summarises articles on three main topics: diagnostic and prognostic biomarkers, presepsin as new biomarkers, and outcome studies. According to the review, presepsin is specific biomarker for bacterial infections compare with CRP and PCT. It may be useful to evaluate the empirical antibiotic outcome in sepsis condition.

The Dynamical Assessment of Inflammatory Biomarkers in Predicting the Outcome of Septic Patients and the Response to Antimicrobial Therapy

Aims

To evaluate the kinetics of inflammatory biomarkers in septic patients in order to identify the most reliable predictor of unfavorable outcome.

Methods

A prospective analysis of septic patients was performed. Median levels of neutrophil/lymphocyte count ratio, fibrinogen, C-reactive protein and procalcitonin were dynamically assessed and comparatively analyzed.

Results

Seventy-seven patients were included. Descendent kinetic patterns were registered for all biomarkers, except C-reactive protein. At 24 hours, neutrophil/lymphocyte count ratio significantly decreased in 42.85% of cases, procalcitonin in 37.33%, C-reactive protein in 16.12% and fibrinogen in 1.58% of cases. At 72 hours, procalcitonin decreased to one-half in 70% of cases and neutrophil/lymphocyte count ratio in 67.53% of cases.

Conclusions

Neutrophil/lymphocyte count ratio and procalcitonin significantly decreased in the first 72 hours, while C-reactive protein increased in the first 24 hours. The proportions of patients with major decrease of baseline values were higher for neutrophil/lymphocyte count ratio and procalcitonin.

Procalcitonin in respiratory disease: use as a biomarker for diagnosis and guiding antibiotic therapy

Procalcitonin (PCT) is a peptide measurable in serum which becomes elevated in response to bacterial infection. Multiple trials have explored the safety and efficacy of using PCT as a biomarker to guide decisions about starting or stopping antibiotic therapy in a wide variety of situations, and PCT assays have recently been approved by the Federal Drug Administration (FDA) in the US for use in both sepsis and respiratory tract infections. While there have been a number of promising results particularly in acute respiratory tract infections and intensive care unit settings, problems including adherence to protocol, cost of the assay and improved antimicrobial stewardship more generally, have limited more widespread adoption.

This educational article summarises the evidence for the use of procalcitonin as a biomarker of bacterial infection across the spectrum of respiratory disease and reviews how the use of procalcitonin-guided antibiotic therapy is reflected in current major international guidelines.

Procalcitonin has been widely investigated as a biomarker of bacterial infection to aid diagnosis and decisions to start or stop antibiotics in a range of conditions, including in diseases of the lower respiratory tracthttp://bit.ly/2ZgDwNO

The use of procalcitonin for the management of sepsis in Internal Medicine wards: current evidence

Procalcitonin (PCT) is a circulating polypeptide produced in response to bacterial infections. Studies conducted in the Intensive Care Unit (ICU) setting have demonstrated its utility as a biomarker of bacterial infection and sepsis. Thus, PCT is widely used to distinguish between sepsis and SIRS, and to guide antibiotic therapy. At present sepsis represents a frequent diagnosis among patients admitted to internal medicine (IM) departments. Basing on the knowledge derived from ICU studies, the use of PCT has become routine in non-intensive wards, contributing to improve the management of sepsis. However, some differences between the two populations of patients - the IM being older, affected by multiple chronic comorbidities and lacking of invasive monitoring - could limit the generalizability of ICU results. Most of the studies on PCT conducted in the IM setting have focused on chronic obstructive pulmonary disease, pneumonia and sepsis. Although PCT represents one of the best biomarker available in routine clinical practice, there are uncertainties on the optimal cut-offs to be used for starting or discontinuing antibiotic treatment in patients with suspected bacterial infection or sepsis, for predicting outcome and on the role of PCT variations during antibiotic treatment. Moreover, several diseases can produce an elevation of PCT levels, thus producing false positive results. This represents a narrative review summarizing current evidences on PCT for the management of sepsis in an Internal Medicine wards, highlighting differences with ICU, with a special focus on the role of PCT variations as predictor of outcomes in non-ICU wards.

Adhering to the procalcitonin algorithm allows antibiotic therapy to be shortened in patients with ventilator-associated pneumonia

PURPOSE

Ventilator-associated pneumonia (VAP) increases exposure to antibiotics. Physicians are however reluctant to shorten treatment, arguing this could lead to failures and worse outcome. Monitoring procalcitonin (PCT) has proven effective for decreasing exposure to antibiotics in randomized controlled trials, but additional "real-life" studies are needed.

MATERIALS AND METHODS

All patients with VAP in whom ABT was stopped before death or discharge were included in this 5-year prospective cohort study. Patients in whom ABT was stopped in accordance with the algorithm ("PCT-guided" group: ABT withdrawal strongly encouraged if PCT < 0.5 ng/mL or < 80% peak value) were compared to those with ABT continuation despite PCT decrease ("not PCT-guided" group). The primary endpoint was ABT duration. The secondary endpoint was unfavorable VAP outcome (i.e. death or relapse).

RESULTS

We included 157 of the 316 patients with microbiologically-proven VAP. The algorithm was overruled in 81 patients (51.6%). ABT duration was significantly longer in these patients than in the PCT-guided group (9.5 vs. 8.0 days; p = .02), although baseline and VAP characteristics did not differ. The rate of unfavorable outcomes was comparable (46.9% vs. 51.3%; p = .69).

CONCLUSIONS

PCT-guided ABT adherence appears safe for patients with VAP and is likely to reduce exposure to antibiotics.

Early prediction of treatment failure in severe community-acquired pneumonia: The PRoFeSs score

PURPOSE

To identify a single/panel of biomarkers and to provide a point score that, after 48 h of treatment, could early predict treatment failure at fifth day of Intensive Care Unit (ICU) stay in severe community-acquired pneumonia (SCAP) patients.

MATERIALS AND METHODS

Single-center, prospective cohort study of 107 ICU patients with SCAP. Primary outcome included death or absence of improvement in Sequential Organ Failure Assessment score by ≥2 points within 5 days of treatment. Biomarkers were evaluated within 12 h of first antibiotic dose (D1) and 48 h after the first assessment (D3).

RESULTS

A model based on Charlson's score and a panel of biomarkers (procalcitonin on D1 and D3, B-natriuretic peptide on D1, D-dimer and lactate on D3) had good discrimination for primary outcome in both derivation (AUC 0.82) and validation (AUC 0.76) samples and was well calibrated (X² = 0.98; df = 1; p = .32). A point score system (PRoFeSs score) built on the estimates of regression coefficients presented good discrimination (AUC 0.81; 95% Confidence Interval 0.72-0.89) for primary outcome.

CONCLUSIONS

In SCAP, a combination of biomarkers measured at admission and 48 h later may early predict treatment failure. PRoFeSs score may recognize patients with poor short-term prognosis.

Antimicrobial Resistance: An Antimicrobial/Diagnostic Stewardship and Infection Prevention Approach

Antimicrobial resistance (AR) is one of the most serious public health threats today, which has been accelerated by the overuse and misuse of antimicrobials in humans and animals plus inadequate infection prevention. Numerous studies have shown a relationship between antimicrobial use and resistance. Antimicrobial stewardship (AS) programs have been shown to improve patient outcomes, reduce antimicrobial adverse events, and decrease AR. AS programs, when implemented alongside infection control measures, especially hand-hygiene interventions, were more effective than implementation of AS alone. Targeted coordination and prevention strategies are critical to stopping the spread of multidrug-resistant organisms.

The combination of cerebrospinal fluid procalcitonin, lactate, interleukin-8 and interleukin-10 concentrations for the diagnosis of postneurosurgical bacterial meningitis: A prospective study

Background

The differential diagnosis between postneurosurgical bacterial meningitis and aseptic meningitis remains challenging both for the clinician and the laboratory. Combinations of markers, as opposed to single ones, may improve diagnosis and thereby survival.

Methods

This prospective cohort study included patients with suspected bacterial meningitis after neurosurgery. The patients were divided into two groups according to the diagnostic criteria of meningitis involving a postneurosurgical bacterial meningitis group and a postneurosurgical aseptic meningitis group. Four biomarkers, including cerebrospinal fluid procalcitonin, lactate, interleukin-8 and interleukin-10 were assayed separately, and three algorithms were constructed using a linear combination. The area under the receiver operating characteristic curve was used to compare their performances.

Results

A cohort of 112 patients was enrolled in our study. Forty-three patients were diagnosed with postneurosurgical bacterial meningitis, and the cerebrospinal fluid values of their biomarkers were higher in patients with postneurosurgical bacterial meningitis than with postneurosurgical aseptic meningitis. The area under the receiver operating characteristic curves for the detection of postneurosurgical bacterial meningitis were 0.803 (95% confidence interval [CI], 0.724–0.883) for procalcitonin; 0.936 (95% CI, 0.895–0.977) for lactate; 0.771 (95% CI, 0.683–0.860) for interleukin-8; 0.860 (95% CI, 0.797–0.929) for interleukin-10; 0.937 (95% CI, 0.897–0.977) for the composite two-marker test; 0.945 (95% CI, 0.908–0.982) for the composite three-marker test and 0.954 (95% CI, 0.922–0.989) for the composite of all tests. The area under the receiver operating characteristic curves of the combination tests were greater than those of the single markers.

Conclusions

Combining information from several markers improved the diagnostic accuracy in detecting postneurosurgical bacterial meningitis.

Mr-Proadm Elevation Upon Icu Admission Predicts the Outcome of Septic Patients and is Correlated with Upcoming Fluid Overload

BACKGROUND

Among septic patients admitted to the intensive care unit (ICU), early recognition of those with the highest risk of death is of paramount importance. We evaluated the prognostic value of Procalcitonin (PCT), mid regional-proadrenomedullin (MR-proADM), copeptine and CT-proendothelin 1 (CT-ProET 1) concentrations.

METHODS

This was a prospective cohort study, which included 173 septic patient admitted to one ICU. Blood samples for biomarker measurements were obtained upon admission and on day 5. The predictive value of each biomarker regarding the risk of death at day 28 was assessed. The fluid balance was evaluated from admission to day 5.

RESULTS

All cause ICU mortality was 36.4%. All the biomarkers except CT-ProET-1 were significantly more elevated in the non-survivors than in the survivors upon day 1. This was especially true for MR-proADM (8.6 [5.9] vs. 4.4 [3.9] nmol/L; P < 0.0001) and for the CT-proET-1/MR-proADM ratio (52.9 [22.4] vs. 31.3 [26.6] arbitrary units; P < 0.0001). The best AUROCC values on day 1 were obtained with MR-ProADM and the CT-proET-1/MR-proADM ratio as well (0.75 [0.67-0.85] and 0.82 [0.75-0.89]; 95% CI, respectively). An improved accuracy was achieved on day 5. Moreover, MR-ProADM baseline levels and fluid balance over the 5-day period following ICU admission were strongly correlated (Rho = 0.41; P < 0.001).

CONCLUSIONS

In patients admitted to the ICU with sepsis, MR-ProADM on admission was the best predictor of short-term clinical outcome if compared with others. This could be related to its ability to predict fluid sequestration.

Role of Procalcitonin in the Management of Infected Patients in the Intensive Care Unit

The combination of molecular pathogen diagnostics and the biomarker procalcitonin (PCT) are changing the use of antimicrobials in patients admitted to critical care units with severe community-acquired pneumonia, possible septic shock, or other clinical syndromes. An elevated serum PCT level is good supportive evidence of a bacterial pneumonia, whereas a low serum PCT level virtually eliminates an etiologic role for bacteria even if the culture for a potential bacterial pathogen is positive. Serum PCT levels can be increased in any shocklike state; a low PCT level eliminates invasive bacterial infection as an etiology in more than 90% of patients.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016)

BACKGROUND AND PURPOSE

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 and published in the Journal of JSICM, [2017; Volume 24 (supplement 2)] 10.3918/jsicm.24S0001 and Journal of Japanese Association for Acute Medicine [2017; Volume 28, (supplement 1)] http://onlinelibrary.wiley.com/doi/10.1002/jja2.2017.28.issue-S1/issuetoc.This abridged English edition of the J-SSCG 2016 was produced with permission from the Japanese Association of Acute Medicine and the Japanese Society for Intensive Care Medicine.

METHODS

Members of the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine were selected and organized into 19 committee members and 52 working group members. The guidelines were prepared in accordance with the Medical Information Network Distribution Service (Minds) creation procedures. The Academic Guidelines Promotion Team was organized to oversee and provide academic support to the respective activities allocated to each Guideline Creation Team. To improve quality assurance and workflow transparency, a mutual peer review system was established, and discussions within each team were open to the public. Public comments were collected once after the initial formulation of a clinical question (CQ) and twice during the review of the final draft. Recommendations were determined to have been adopted after obtaining support from a two-thirds (> 66.6%) majority vote of each of the 19 committee members.

RESULTS

A total of 87 CQs were selected among 19 clinical areas, including pediatric topics and several other important areas not covered in the first edition of the Japanese guidelines (J-SSCG 2012). The approval rate obtained through committee voting, in addition to ratings of the strengths of the recommendation, and its supporting evidence were also added to each recommendation statement. We conducted meta-analyses for 29 CQs. Thirty-seven CQs contained recommendations in the form of an expert consensus due to insufficient evidence. No recommendations were provided for five CQs.

CONCLUSIONS

Based on the evidence gathered, we were able to formulate Japanese-specific clinical practice guidelines that are tailored to the Japanese context in a highly transparent manner. These guidelines can easily be used not only by specialists, but also by non-specialists, general clinicians, nurses, pharmacists, clinical engineers, and other healthcare professionals.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016)

Background and Purpose

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 in Japanese. An English-language version of these guidelines was created based on the contents of the original Japanese-language version.

Methods

Members of the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine were selected and organized into 19 committee members and 52 working group members. The guidelines were prepared in accordance with the Medical Information Network Distribution Service (Minds) creation procedures. The Academic Guidelines Promotion Team was organized to oversee and provide academic support to the respective activities allocated to each Guideline Creation Team. To improve quality assurance and workflow transparency, a mutual peer review system was established, and discussions within each team were open to the public. Public comments were collected once after the initial formulation of a clinical question (CQ), and twice during the review of the final draft. Recommendations were determined to have been adopted after obtaining support from a two-thirds (>66.6%) majority vote of each of the 19 committee members.

Results

A total of 87 CQs were selected among 19 clinical areas, including pediatric topics and several other important areas not covered in the first edition of the Japanese guidelines (J-SSCG 2012). The approval rate obtained through committee voting, in addition to ratings of the strengths of the recommendation and its supporting evidence were also added to each recommendation statement. We conducted meta-analyses for 29 CQs. Thirty seven CQs contained recommendations in the form of an expert consensus due to insufficient evidence. No recommendations were provided for 5 CQs.

Conclusions

Based on the evidence gathered, we were able to formulate Japanese-specific clinical practice guidelines that are tailored to the Japanese context in a highly transparent manner. These guidelines can easily be used not only by specialists, but also by non-specialists, general clinicians, nurses, pharmacists, clinical engineers, and other healthcare professionals.

Predictors of treatment failure and clinical stability in patients with community acquired pneumonia

Community acquired pneumonia (CAP) is the leading infectious cause of mortality worldwide with approximately 10% of patients hospitalized requiring intensive care unit (ICU) admission. The ability to predict clinical stability (CS) and treatment failure (TF) enables the clinician to alter antibiotics appropriately, facilitate a timely ICU admission, or arrange a suitable discharge. The detection of CS and TF can be difficult and changes in clinical signs may be subtle or delayed. Thus clinical scores and biomarkers are routinely used to identify severity and monitor clinical progression. The evidence, however, is vast and the definitive role of these systems is at times difficult to elucidate. The aim of this review is to analyse the current literature and to provide a rational and clinically focused view of the predictive utility of various systems used to identify CS and TF in CAP.

Effect of procalcitonin-guided antibiotic treatment on mortality in acute respiratory infections: a patient level meta-analysis

BACKGROUND

In February, 2017, the US Food and Drug Administration approved the blood infection marker procalcitonin for guiding antibiotic therapy in patients with acute respiratory infections. This meta-analysis of patient data from 26 randomised controlled trials was designed to assess safety of procalcitonin-guided treatment in patients with acute respiratory infections from different clinical settings.

METHODS

Based on a prespecified Cochrane protocol, we did a systematic literature search on the Cochrane Central Register of Controlled Trials, MEDLINE, and Embase, and pooled individual patient data from trials in which patients with respiratory infections were randomly assigned to receive antibiotics based on procalcitonin concentrations (procalcitonin-guided group) or control. The coprimary endpoints were 30-day mortality and setting-specific treatment failure. Secondary endpoints were antibiotic use, length of stay, and antibiotic side-effects.

FINDINGS

We identified 990 records from the literature search, of which 71 articles were assessed for eligibility after exclusion of 919 records. We collected data on 6708 patients from 26 eligible trials in 12 countries. Mortality at 30 days was significantly lower in procalcitonin-guided patients than in control patients (286 [9%] deaths in 3336 procalcitonin-guided patients vs 336 [10%] in 3372 controls; adjusted odds ratio [OR] 0·83 [95% CI 0·70 to 0·99], p=0·037). This mortality benefit was similar across subgroups by setting and type of infection (p_interactions>0·05), although mortality was very low in primary care and in patients with acute bronchitis. Procalcitonin guidance was also associated with a 2·4-day reduction in antibiotic exposure (5·7 vs 8·1 days [95% CI -2·71 to -2·15], p<0·0001) and a reduction in antibiotic-related side-effects (16% vs 22%, adjusted OR 0·68 [95% CI 0·57 to 0·82], p<0·0001).

INTERPRETATION

Use of procalcitonin to guide antibiotic treatment in patients with acute respiratory infections reduces antibiotic exposure and side-effects, and improves survival. Widespread implementation of procalcitonin protocols in patients with acute respiratory infections thus has the potential to improve antibiotic management with positive effects on clinical outcomes and on the current threat of increasing antibiotic multiresistance.

FUNDING

National Institute for Health Research.

Procalcitonin Impairs Endothelial Cell Function and Viability

BACKGROUND

Procalcitonin is used as a diagnostic tool for the identification and risk stratification of septic patients. Procalcitonin plasma concentrations tightly correlate with the severity of the ongoing inflammatory reaction and can rise up to 10,000-fold. Impairment of endothelial cell function plays an important role in the pathogenesis of hypotension and disturbed organ perfusion during sepsis. We investigated the possible effects of procalcitonin itself on endothelial cell function and viability.

METHODS

Human endothelial cells were exposed to 0.01 to 100 ng/mL procalcitonin and investigated for endothelial permeability using transwells, migration in a scratch wound assay and new capillary formation on extracellular matrix in vitro. Tumor necrosis factor-α and vascular endothelial growth factor served as positive controls. Procalcitonin's impact on the response of endothelial cells toward ischemia was investigated in vivo in the murine model of unilateral femoral artery ligation. Procalcitonin-exposed endothelial cells were subjected to immunoblot for the investigation of vascular endothelial-cadherin expression and angiogenic signaling pathways. Flow cytometry was used for the detection of inflammatory activation and viability, and genomic analysis was performed. Data are presented as difference in means and 95% confidence intervals; statistical analyses were performed using analysis of variance/Bonferroni, and P values are reported as adjusted for multiple comparisons (Padjust).

RESULTS

Tumor necrosis factor-α and 0.1 ng/mL procalcitonin induced endothelial barrier disruption after incubation of endothelial monolayers for 6 hours (-2.53 [-4.16 to -0.89], P = .0008 and -2.09 [-3.73 to -0.45], Padjust = .0064 compared with vehicle-treated control, respectively). Procalcitonin beginning at concentrations of 0.02 ng/mL reduced endothelial cell migration (0.26 [0.06 to 0.47], Padjust = .0069) and new capillary formation in vitro (0.47 [0.28 to 0.66], Padjust < .0001) contrasting the proangiogenic action of vascular endothelial growth factor. Left ventricular injection of procalcitonin in mice on postoperative day 1, 3, and 5 after induction of ischemia impaired new capillary formation and recovery of hindlimb perfusion in vivo (number of capillaries/mm in the ischemic leg of vehicle-treated versus procalcitonin-treated mice, 852.6 [383.4-1322], Padjust = .0002). Twenty-four-hour incubation with procalcitonin reduced the expression of vascular endothelial-cadherin at 100 ng/mL (0.39 [0.06-0.71], Padjust = .0167) and induced endothelial cell death (apoptosis, -5.4 [-10.67 to -0.13], Padjust = .0431). No alteration in the expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1 or extracellular signal-regulated kinase 1/2, and AKT signaling pathways was observed. Genomic analysis revealed regulation of a variety of genes involved in inflammation, angiogenesis, and cell growth.

CONCLUSIONS

This study found that procalcitonin itself impaired several aspects of endothelial cell function. Procalcitonin-induced loss of endothelial barrier function may contribute to capillary leakage and therapy-refractory hypotension during sepsis. Anti-angiogenic properties of procalcitonin at low concentrations could also identify procalcitonin as a mediator of vascular disease associated with the metabolic syndrome. Future studies are needed to further test procalcitonin as a potential therapeutic target for preserving vascular dysfunction during acute and chronic inflammatory disorders.

Combined use of serum (1,3)-β-D-glucan and procalcitonin for the early differential diagnosis between candidaemia and bacteraemia in intensive care units

Background

This study aimed to assess the combined performance of serum (1,3)-β-d-glucan (BDG) and procalcitonin (PCT) for the differential diagnosis between candidaemia and bacteraemia in three intensive care units (ICUs) in two large teaching hospitals in Italy.

Methods

From June 2014 to December 2015, all adult patients admitted to the ICU who had a culture-proven candidaemia or bacteraemia, as well as BDG and PCT measured closely to the time of the index culture, were included in the study. The diagnostic performance of BDG and PCT, used either separately or in combination, was assessed by calculating the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and positive and negative likelihood ratios (LR+ and LR–). Changes from pre-test probabilities to post-test probabilities of candidaemia and bacteraemia were inferred from Fagan’s nomograms.

Results

One hundred and sixty-six patients were included, 73 with candidaemia (44%) and 93 with bacteraemia (56%). When both markers indicated candidaemia (BDG ≥80 pg/ml and PCT <2 ng/ml) they showed higher PPV (96%) compared to 79% and 66% for BDG or PCT alone, respectively. When both markers indicated bacteraemia (BDG <80 pg/ml and PCT ≥2 ng/ml), their NPV for candidaemia was similar to that of BDG used alone (95% vs. 93%). Discordant BDG and PCT results (i.e. one indicating candidaemia and the other bacteraemia) only slightly altered the pre-test probabilities of the two diseases.

Conclusions

The combined use of PCT and BDG could be helpful in the diagnostic workflow for critically ill patients with suspected candidaemia.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1763-5) contains supplementary material, which is available to authorized users.

Hydrocortisone, Vitamin C, and Thiamine for the Treatment of Severe Sepsis and Septic Shock: A Retrospective Before-After Study

BACKGROUND

The global burden of sepsis is estimated as 15 to 19 million cases annually, with a mortality rate approaching 60% in low-income countries.

METHODS

In this retrospective before-after clinical study, we compared the outcome and clinical course of consecutive septic patients treated with intravenous vitamin C, hydrocortisone, and thiamine during a 7-month period (treatment group) with a control group treated in our ICU during the preceding 7 months. The primary outcome was hospital survival. A propensity score was generated to adjust the primary outcome.

RESULTS

There were 47 patients in both treatment and control groups, with no significant differences in baseline characteristics between the two groups. The hospital mortality was 8.5% (4 of 47) in the treatment group compared with 40.4% (19 of 47) in the control group (P < .001). The propensity adjusted odds of mortality in the patients treated with the vitamin C protocol was 0.13 (95% CI, 0.04-0.48; P = .002). The Sepsis-Related Organ Failure Assessment score decreased in all patients in the treatment group, with none developing progressive organ failure. All patients in the treatment group were weaned off vasopressors, a mean of 18.3 ± 9.8 h after starting treatment with the vitamin C protocol. The mean duration of vasopressor use was 54.9 ± 28.4 h in the control group (P < .001).

CONCLUSIONS

Our results suggest that the early use of intravenous vitamin C, together with corticosteroids and thiamine, are effective in preventing progressive organ dysfunction, including acute kidney injury, and in reducing the mortality of patients with severe sepsis and septic shock. Additional studies are required to confirm these preliminary findings.

Procalcitonin - Assisted Antibiotic Strategy in Sepsis

Sepsis is one of the biggest challenges in critical care nowadays. Defining sepsis is a difficult task on its own and its diagnosis and treatment requires well trained, devoted personnel with interdisciplinary collaboration in order to provide the patients the best chance for survival. Immediate resuscitation, early adequate antimicrobial therapy, source control and highly sophisticated organ support on the intensive care units are all inevitable necessities for successful recovery. To help fast and accurate diagnosis biomarkers have been measured for decades. Procalcitonin (PCT) is one of the most studied, but the results are conflicting. Sepsis means a very loose cohort of a large heterogeneous patient population, hence defining certain cut off values for PCT to differentiate between different severities of the disease is almost impossible. Clinicians first have to understand the pathophysiological background of sepsis to be able to interpret correctly the PCT results. Nevertheless, PCT has been shown to have the best sensitivity and specificity to indicate infection, antibiotic appropriateness and stopping therapy. In this article we will focus on some important aspects of pathophysiology and advice on how to implement that in the everyday clinical practice. We believe that this multimodal evaluation of the clinical picture together with PCT results can be a useful tool to make the most out of the PCT results, and do the best for patients on the ICU.

Diagnostic and prognostic value of procalcitonin for early intracranial infection after craniotomy

Intracranial infection is a common clinical complication after craniotomy. We aimed to explore the diagnostic and prognostic value of dynamic changing procalcitonin (PCT) in early intracranial infection after craniotomy. A prospective study was performed on 93 patients suspected of intracranial infection after craniotomy. Routine peripheral venous blood was collected on the day of admission, and C reactive protein (CRP) and PCT levels were measured. Cerebrospinal fluid (CSF) was collected for routine biochemical, PCT and culture assessment. Serum and CSF analysis continued on days 1, 2, 3, 5, 7, 9, and 11. The patients were divided into intracranial infection group and non-intracranial infection group; intracranial infection group was further divided into infection controlled group and infection uncontrolled group. Thirty-five patients were confirmed with intracranial infection after craniotomy according to the diagnostic criteria. The serum and cerebrospinal fluid PCT levels in the infected group were significantly higher than the non-infected group on day 1 (P<0.05, P<0.01). The area under curve of receiver operating characteristics was 0.803 for CSF PCT in diagnosing intracranial infection. The diagnostic sensitivity and specificity of CSF PCT was superior to other indicators. The serum and CSF PCT levels have potential value in the early diagnosis of intracranial infection after craniotomy. Since CSF PCT levels have higher sensitivity and specificity, dynamic changes in this parameter could be used for early detection of intracranial infection after craniotomy, combined with other biochemical indicators.

Procalcitonin levels in sepsis and its association with clinical outcome in southern India

Procalcitonin has been found to be a good marker for the diagnosis of sepsis. However, data on procalcitonin levels to predict the clinical outcome in patients with sepsis are limited. The aim of our study was to estimate serum procalcitonin levels in patients with sepsis and to identify its relationship with the clinical outcome. This was a prospective observational study conducted on 112 patients with sepsis admitted to the medical wards and medical intensive care unit of a tertiary care teaching hospital. Serum procalcitonin was measured at baseline before antibiotic administration and on day 5. The clinical outcome studied was death or survival on day 28. Baseline mean serum procalcitonin was highest in patients with septic shock and lowest in patients having sepsis without organ dysfunction. Mean values of procalcitonin at baseline and on day 5 were significantly higher in non-survivors when compared with survivors. There was a significant difference in the change in procalcitonin levels from baseline to day 5 between survivors and non-survivors, with survivors having declining values on day 5 while non-survivors had increasing values from baseline. The baseline APACHE II and SOFA scores also showed a significant correlation with the baseline procalcitonin level. Declining values of procalcitonin therefore indicate a favourable clinical outcome in patients with sepsis.

Prognostic value of procalcitonin in hospitalized patients with lower respiratory tract infections

Lower respiratory tract infections are common and potentially lethal conditions and are a major cause of inadequate antibiotic prescriptions. Characterization of disease severity and prognostic prediction in affected patients can aid disease management and can increase accuracy in determining the need for and place of hospitalization. The inclusion of biomarkers, particularly procalcitonin, in the decision taken process is a promising strategy. This study aims to present a narrative review of the potential applications and limitations of procalcitonin as a prognostic marker in hospitalized patients with lower respiratory tract infections. The studies on this topic are heterogeneous with respect to procalcitonin measurement techniques, cutoff values, clinical settings, and disease severity. The results show that procalcitonin delivers moderate performance for prognostic prediction in patients with lower respiratory tract infections; its predictive performance was not higher than that of classical methods, and knowledge of procalcitonin levels is most useful when interpreted together with other clinical and laboratory results. Overall, repeated measurement of the procalcitonin levels during the first days of treatment provides more prognostic information than a single measurement; however, information on the cost-effectiveness of this procedure in intensive care patients is lacking. The results of studies that evaluated the prognostic value of initial procalcitonin levels in patients with community-acquired pneumonia are more consistent and have greater potential for practical application; in this case, low procalcitonin levels identify those patients with a low risk of adverse outcomes.

Tools for outcome prediction in patients with community acquired pneumonia

INTRODUCTION

Community-acquired pneumonia (CAP) is one of the most common causes of mortality world-wide. The mortality rate of patients with CAP is influenced by the severity of the disease, treatment failure and the requirement for hospitalization and/or intensive care unit (ICU) management, all of which may be predicted by biomarkers and clinical scoring systems. Areas covered: We review the recent literature examining the efficacy of established and newly-developed clinical scores, biological and inflammatory markers such as C-Reactive protein (CRP), procalcitonin (PCT) and Interleukin-6 (IL-6), whether used alone or in conjunction with clinical severity scores to assess the severity of CAP, predict treatment failure, guide acute in-hospital or ICU admission and predict mortality. Expert commentary: The early prediction of treatment failure using clinical scores and biomarkers plays a developing role in improving survival of patients with CAP by identifying high-risk patients requiring hospitalization or ICU admission; and may enable more efficient allocation of resources. However, it is likely that combinations of scoring systems and biomarkers will be of greater use than individual markers. Further larger studies are needed to corroborate the additive value of these markers to clinical prediction scores to provide a safer and more effective assessment tool for clinicians.

Value of Procalcitonin Measurement for Early Evidence of Severe Bacterial Infections in the Pediatric Intensive Care Unit

OBJECTIVES

To determine whether peak blood procalcitonin (PCT) measured within 48 hours of pediatric intensive care unit (PICU) admission can differentiate severe bacterial infections from sterile inflammation and viral infection and identify potential subgroups of PICU patients for whom PCT may not have clinical utility.

STUDY DESIGN

This was a retrospective, observational study of 646 critically ill children who had PCT measured within 48 hours of admission to an urban, academic PICU. Patients were stratified into 6 categories by infection status. We compared test characteristics for peak PCT, C-reactive protein (CRP), white blood cell count (WBC), absolute neutrophil count (ANC), and % immature neutrophils. The area under the receiver operating characteristic curve was determined for each biomarker to discriminate bacterial infection.

RESULTS

The area under the receiver operating characteristic curve was similar for PCT (0.73, 95% CI 0.69, 0.77) and CRP (0.75, 95% CI 0.71, 0.79; P = .36), but both outperformed WBC, ANC, and % immature neutrophils (P < .01 for all pairwise comparisons). The combination of PCT and CRP was no better than either PCT or CRP alone. Diagnostic patterns prone to false-positive and false-negative PCT values were identified.

CONCLUSIONS

Peak blood PCT measured close to PICU admission was not superior to CRP in differentiating severe bacterial infection from viral illness and sterile inflammation; both PCT and CRP outperformed WBC, ANC, and % immature neutrophils. PCT appeared especially prone to inaccuracies in detecting localized bacterial central nervous system infections or bacterial coinfection in acute viral illness causing respiratory failure.

Significance of soluble triggering receptor expressed on myeloid cells-1 elevation in patients admitted to the intensive care unit with sepsis

Background

Among septic patients admitted to the intensive care unit (ICU), early recognition of those with the highest risk of death is of paramount importance. Since clinical judgment is sometimes uncertain biomarkers could provide additional information likely to guide critical illness management. We evaluated the prognostic value of soluble Triggering Receptor Expressed by Myeloid cells 1 (sTREM-1), procalcitonin (PCT) and leucocyte surface expression of CD64.

Methods

This was a prospective cohort study, which included 190 septic patient admitted to the ICU in two hospitals. Blood samples for biomarker measurements were obtained upon admission and thereafter. The Simplified Acute Physiology Score (SAPS) II and the Sequential Organ Failure Assessment (SOFA) score were calculated. The primary outcome was all-cause death in the ICU.

Results

The mortality rate reached 25.8 %. The best predictive value of the three biomarkers was obtained with baseline sTREM-1, although clinical scores outperformed this. Accuracy was greater in patients without prior exposure to antibiotics and in those with proven bacterial infection. Adding sTREM-1 levels to SAPS II increased its specificity to 98 %. The soluble TREM-1 level, core temperature and SAPS II value were the only independent predictors of death after adjustment for potential confounders. A decrease in sTREM-1 with time was also more pronounced in survivors than in non-survivors.

Conclusions

sTREM-1 was found to be the best prognostic biomarker among those tested. Both baseline values and variations with time seemed relevant. Although SAPS II outperformed sTREM-1 regarding the prediction of ICU survival, the biomarker could provide additional information.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1893-4) contains supplementary material, which is available to authorized users.

Reduction in procalcitonin level and outcome in critically ill children with severe sepsis/septic shock-A pilot study

PURPOSE

To investigate if reduction in procalcitonin (PCT) provides useful information about 28-day mortality in children with severe sepsis or septic shock.

MATERIALS AND METHODS

Design: Prospective observational study.

SETTING

Mixed adult-pediatric intensive care unit in a teaching hospital.

SUBJECTS

Children up to 18 years of age admitted with severe sepsis or septic shock between March 2011 and June 2013. Procalcitonin measured using electrochemiluminescence immunoassay on the day of admission with sepsis (D0) and 72-96 hours later (D4). Reduction in PCT from D0 to D4 correlated with the primary outcome, that is, 28-day mortality.

RESULTS

Twenty-five children of median age of 14 years (range, 6-18 years) were included, but 5 died before D4 after admission. Six of the remaining 20 children died between D4 and D28, and 14 survived to D28. At admission, the median of the Pediatric Risk of Mortality III score was 10 (interquartile range [IQR], 5-16) and that of the Sequential Organ Failure Assessment score was 11 (IQR, 7-15). The median PCT level was 9.7 ng/mL on D0 (n = 25) and 3.3 ng/mL on D4 (n = 20). On D0, the median PCT level was 25.0 ng/mL in the 14 survivors and 8.4 ng/mL in the 11 nonsurvivors (P = .075). On D4, the median PCT level was 3.1 ng/mL in the 14 survivors and 4.5 ng/mL in the 6 nonsurvivors who lived to D4 (P = .71); the reduction in PCT (D0 minus D4) was 17.3 ng/mL (IQR, 3.5-38.0 ng/mL) in the survivors and -1.1 ng/mL (IQR, -24.9 to 8.6 ng/mL) in the 6 nonsurvivors (P = .017). Percent reduction in PCT (100 * [D0 - D4]/D0) was 75.5% (IQR, 54.8%-80.7%) in the survivors and -200.3% (IQR, -937.8% to 42.4%) in the 6 nonsurvivors (P = .006).

CONCLUSION

This small pilot study suggests that further studies are indicated to determine whether children with severe sepsis or septic shock are less likely to die if they have a reduction in PCT more than 50% in the first 4 days in intensive care.

[Procalcitonin as a tool for the assessment of successful therapy of severe sepsis : An analysis using clinical routine data]

INTRODUCTION

Procalcitonin (PCT) is a well-evaluated biomarker for the detection of severe bacterial infections and monitoring effectiveness of antibiotic therapy. This study aims to evaluate the usefulness of PCT in a clinical routine setting.

MATERIALS AND METHODS

Of 358,763 clinical cases from 7 German hospitals in 2012 and 2013, 3854 cases had an ICD-10 code representing sepsis. A total of 1778 cases had pathologic PCT and one episode of infection. Of those, 671 showed a series of measures that was suitable to assess treatment success using PCT reduction. Propensity score matching was used to create two comparable groups with 211 patients in each group.

RESULTS

The group with PCT reduction within 12 days showed a highly significant better proportion of survival (146/211 vs. 17/211; p < 0.0001). The odds ratio for death according to PCT reduction vs. nonreduction is 25.64 (p < 0.0001; 95 % CI: 14.49-45.45). PCT was normalized after an average of 6.2 days.

DISCUSSION

The difference in survival implicates that PCT reduction is a suitable surrogate parameter to indicate successful antimicrobial therapy. Successful antibiotic therapy is a proven predictor for survival in sepsis. This study also showed concordant results in the group of patients with sepsis after abdominal surgery. Results from subgroup analyses confirm the initial findings. PCT reduction was used as surrogate for therapy success, as the antimicrobial therapy was not electronically available.

CONCLUSION

PCT reduction is a strong predictor for survival. However, the data show that overall use of PCT to monitor sepsis therapy is not yet routinely established. Hospitals should establish algorithms for sepsis treatment that include PCT for the assessment of adequacy and the monitoring of success of the antimicrobial therapy.

Time courses of changes of para-, meta-, and ortho-tyrosine in septic patients: A pilot study

OBJECTIVES

Sepsis is associated with oxidative stress. Due to oxidative stress, three tyrosine isoforms, para-, meta-, and ortho-tyrosine (p-, m-, and o-Tyr), can be formed non-enzymatically in smaller amounts. p-Tyr is mainly formed physiologically in the kidneys through the activity of the phenylalanine hydroxylase enzyme. The three tyrosine isoforms may undergo different renal handling.

METHODS

Twenty septic patients were involved in the study and 25 healthy individuals served as controls. Blood and urine levels of p-, m-, and o-Tyr were measured on admission and four consecutive days.

RESULTS

Serum m-Tyr levels were higher in septic patients than in controls on days 2 (P = 0.031) and 3 (P = 0.035). Serum p-Tyr levels were lower in the cases than in controls on days 1 (P = 0.005) and 2 (P = 0.040), and subsequently normalized due to a day-by-day elevation (P = 0.002). The tendency of urinary m-Tyr concentration was decreasing (P = 0.041), while that of urinary p-Tyr concentration was increasing (P = 0.001). Fractional excretion of m-Tyr (FEm-Tyr) showed a decreasing tendency (P = 0.009), and was, on all days, higher than FEp-Tyr, which remained near-normal, less than 4%. Procalcitonin showed significant correlation with FEm-Tyr (r = 0.454; P < 0.001).

DISCUSSION

Our data suggest that the oxidative stress marker m-Tyr and physiologic p-Tyr may be handled differently in septic patients. The excretion of m-Tyr correlates with inflammation. m-Tyr may be actively secreted or produced in the kidney in some patients, whereas the decreased serum level of p-Tyr is a consequence of diminished renal production and not of renal loss.