Procalcitonin and mid-regional pro-adrenomedullin test combination in sepsis diagnosis

Navigating the Modern Landscape of Sepsis: Advances in Diagnosis and Treatment

Sepsis poses a significant threat to human health due to its high morbidity and mortality rates worldwide. Traditional diagnostic methods for identifying sepsis or its causative organisms are time-consuming and contribute to a high mortality rate. Biomarkers have been developed to overcome these limitations and are currently used for sepsis diagnosis, prognosis prediction, and treatment response assessment. Over the past few decades, more than 250 biomarkers have been identified, a few of which have been used in clinical decision-making. Consistent with the limitations of diagnosing sepsis, there is currently no specific treatment for sepsis. Currently, the general treatment for sepsis is conservative and includes timely antibiotic use and hemodynamic support. When planning sepsis-specific treatment, it is important to select the most suitable patient, considering the heterogeneous nature of sepsis. This comprehensive review summarizes current and evolving biomarkers and therapeutic approaches for sepsis.

Prognostic differences in sepsis caused by gram-negative bacteria and gram-positive bacteria: a systematic review and meta-analysis

BACKGROUND

Bacteria are the main pathogens that cause sepsis. The pathogenic mechanisms of sepsis caused by gram-negative and gram-positive bacteria are completely different, and their prognostic differences in sepsis remain unclear.

METHODS

The PubMed, Web of Science, Cochrane Library, and Embase databases were searched for Chinese and English studies (January 2003 to September 2023). Observational studies involving gram-negative (G (-))/gram-positive (G (+)) bacterial infection and the prognosis of sepsis were included. The stability of the results was evaluated by sensitivity analysis. Funnel plots and Egger tests were used to check whether there was publication bias. A meta-regression analysis was conducted on the results with high heterogeneity to identify the source of heterogeneity. A total of 6949 articles were retrieved from the database, and 45 studies involving 5586 subjects were included after screening according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Twenty-seven high-quality studies and 18 moderate-quality studies were identified according to the Newcastle‒Ottawa Scale score. There was no significant difference in the survival rate of sepsis caused by G (-) bacteria and G (+) bacteria (OR 0.95, 95% CI 0.70-1.28). Subgroup analysis according to survival follow-up time showed no significant difference. The serum concentrations of C-reactive protein (CRP) (SMD = 0.39, 95% CI 0.02-0.76), procalcitonin (SMD = 1.95, 95% CI 1.32-2.59) and tumor necrosis factor-alpha (TNF-α) (MD = 0.31, 95% CI 0.25-0.38) in the G (-) bacterial infection group were significantly higher than those in the G (+) bacterial infection group, but there was no significant difference in IL-6 (SMD = 1.33, 95% CI - 0.18-2.84) and WBC count (MD = - 0.15, 95% CI - 0.96-00.66). There were no significant differences between G (-) and G (+) bacteria in D dimer level, activated partial thromboplastin time, thrombin time, international normalized ratio, platelet count, length of stay or length of ICU stay. Sensitivity analysis of the above results indicated that the results were stable.

CONCLUSION

The incidence of severe sepsis and the concentrations of inflammatory factors (CRP, PCT, TNF-α) in sepsis caused by G (-) bacteria were higher than those caused by G (+) bacteria. The two groups had no significant difference in survival rate, coagulation function, or hospital stay. The study was registered with PROSPERO (registration number: CRD42023465051).

Comparison of presepsin and Mid-regional pro-adrenomedullin in the diagnosis of sepsis or septic shock: a systematic review and meta-analysis

BACKGROUND

The early diagnosis of sepsis is hampered by the lack of reliable laboratory measures. There is growing evidence that presepsin and Mid-regional pro-adrenomedullin (MR-proADM) are promising biomarkers in the diagnosis of sepsis. This study was conducted to evaluate and compare the diagnostic value of MR-proADM and presepsin in sepsis patients.

METHODS

We searched Web of Science, PubMed, Embase, China national knowledge infrastructure, and Wanfang up to 22th July, 2022, for studies evaluating the diagnosis performance of presepsin and MR-proADM in adult sepsis patients. Risk of bias was assessed using quadas-2. Pooled sensitivity and specificity were calculated using bivariate meta-analysis. Meta-regression and subgroup analysis were used to find source of heterogeneity.

RESULTS

A total of 40 studies were eventually selected for inclusion in this meta-analysis, including 33 for presepsin and seven for MR-proADM. Presepsin had a sensitivity of 0.86 (0.82-0.90), a specificity of 0.79 (0.71-0.85), and an AUC of 0.90 (0.87-0.92). The sensitivity of MR-proADM was 0.84 (0.78-0.88), specificity was 0.86 (0.79-0.91), and AUC was 0.91 (0.88-0.93). The profile of control group, population, and standard reference may be potential sources of heterogeneity.

CONCLUSIONS

This meta-analysis demonstrated that presepsin and MR-proADM exhibited high accuracy (AUC ≥ 0.90) in the diagnosis of sepsis in adults, with MR-proADM showing significantly higher accuracy than presepsin.

Predictive values of the SOFA score and procalcitonin for septic shock after percutaneous nephrolithotomy

To investigate the value of combination of the Sequential Organ Failure Assessment (SOFA) score and procalcitonin (PCT) for prediction of septic shock after percutaneous nephrolithotomy (PCNL). A total of 1328 patients receiving PCNL for renal calculi were allocated into control group (without septic shock) and septic shock group, and related data were retrospectively collected. Univariate analysis was firstly performed, and the variables with two sided P < 0.10 were then included in logistic regression analysis to determine independent risk factors. Receiver operating characteristic (ROC) curve was utilized to evaluate the predictive values. Area under curve (AUC) was compared using Z test. Postoperative septic shock was developed in 61 patients (4.6%) and not developed in 1267 patients (95.3%). Multivariate analysis demonstrated that SOFA score (OR: 1.316, 95% CI 1.125–1.922), PCT (OR: 1.205, 95% CI 1.071–1.696) and operative time (OR: 1.108, 95% CI 1.032–1.441) were independent risk factors for septic shock with adjustment for sex, history of urolithiasis surgery, positive history of urine culture and history of PCNL. The ROC curves demonstrated that the AUCs of SOFA score and PCT for predicting septic shock after PCNL were 0.896 (95% CI 0.866–0.927) and 0.792 (95% CI 0.744–0.839), respectively. The AUC of their combination was 0.971 (95% CI 0.949–0.990), which was higher than those of individual predictions (vs 0.896, Z = 4.086, P < 0.001; vs 0.792, Z = 6.983, P < 0.001). Both the SOFA score and PCT could be applied in predicting septic shock after PCNL, and their combination could further elevate the diagnostic ability.

New multivariable prediction model PEdiatric SEpsis recognition and stratification (PESERS score) shows excellent discriminatory capacity

AIM

To develop a quantitative predictive scoring model for the early recognition and assessment of paediatric sepsis.

METHODS

Prospective observational study including emergency department and in-hospital febrile patients under 18 years. Sepsis diagnose (Goldstein 2005 definitions) was the main outcome. Variables associated with the outcome were included in a multivariable analysis. Cut-off points, odds ratio and coefficients for the variables kept after the multivariable analysis were identified. The score was obtained from the coefficients, The AUC was obtained from ROC-analysis, and internal validation was performed using k-fold cross-validation.

RESULTS

The analysis included 210 patients. 45 variables were evaluated and the bivariate analysis identified 24 variables associated with the outcome. After the multivariable regression, 11 variables were kept and the score was obtained. The model yielded an excellent AUC of 0.886 (95% CI 0.845-0.927), p < 0.001 for sepsis recognition. With a cut-off value of 5 for the score, we obtained a sensitivity of 98%, specificity of 76.7%, positive predictive value of 87.9% and negative predictive value of 93.3%.

CONCLUSION

The proposed scoring model for paediatric sepsis showed adequate discriminatory capacity and sufficient accuracy, which is of great clinical significance in detecting sepsis early and predicting its severity. Nevertheless external validation is needed before clinical use.

Biomarkers Predicting Tissue Pharmacokinetics of Antimicrobials in Sepsis: A Review

The pathophysiology of sepsis alters drug pharmacokinetics, resulting in inadequate drug exposure and target-site concentration. Suboptimal exposure leads to treatment failure and the development of antimicrobial resistance. Therefore, we seek to optimize antimicrobial therapy in sepsis by selecting the right drug and the correct dosage. A prerequisite for achieving this goal is characterization and understanding of the mechanisms of pharmacokinetic alterations. However, most infections take place not in blood but in different body compartments. Since tissue pharmacokinetic assessment is not feasible in daily practice, we need to tailor antibiotic treatment according to the specific patient’s pathophysiological processes. The complex pathophysiology of sepsis and the ineffectiveness of current targeted therapies suggest that treatments guided by biomarkers predicting target-site concentration could provide a new therapeutic strategy. Inflammation, endothelial and coagulation activation markers, and blood flow parameters might be indicators of impaired tissue distribution. Moreover, hepatic and renal dysfunction biomarkers can predict not only drug metabolism and clearance but also drug distribution. Identification of the right biomarkers can direct drug dosing and provide timely feedback on its effectiveness. Therefore, this might decrease antibiotic resistance and the mortality of critically ill patients. This article fills the literature gap by characterizing patient biomarkers that might be used to predict unbound plasma-to-tissue drug distribution in critically ill patients. Although all biomarkers must be clinically evaluated with the ultimate goal of combining them in a clinically feasible scoring system, we support the concept that the appropriate biomarkers could be used to direct targeted antibiotic dosing.

[Which biomarkers for diagnosis and guidance of anti-infection treatment in sepsis?]

To date no biomarker has been identified bringing together perfect sensitivity and specificity to discriminate between inflammation and infections. Since the 1930s new markers of tissue damage and endothelial damage have been identified but which are incapable of identifying infections in every clinical setting to enable initiation of early antibiotic treatment. In this review the most important classical biomarkers and upcoming new PCR-based approaches are addressed. These markers are highlighted with respect to special clinical settings and to control the success of antibiotic treatment. The issue of discrimination between inflammation and infection is not yet solved. Based on one single biomarker it is impossible to decide whether infection is the reason for the patient's worsening condition but the combination of biomarkers or the integration of new biomarkers may be a meaningful supplement. The measurement of different biomarkers of infection or inflammation is part of the routine in critical care and will be essential in the future.

The Value of Interleukin-10 in the Early Diagnosis of Neonatal Sepsis: A Meta-Analysis

OBJECTIVES

Interleukin-10 is a significant marker in neonatal sepsis. This meta-analysis evaluated the accuracy of interleukin-10 expression in the diagnosis of neonatal sepsis.

DATA SOURCE

Summary of literature review.

STUDY SELECTION

A literature search strategy was developed, including PubMed, EMBASE, Web of Science, MEDLINE, and the Cochrane Library. All publications published till October 1, 2020, were retrieved; the key words were "sepsis" and "interleukin-10."

DATA EXTRACTION

The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were used to evaluate the data, and the heterogeneity of the combined results was tested according to the I2 value.

DATA SYNTHESIS

A total of six articles involving 879 newborns were included in the study. The combined sensitivity was 0.82 (95% CI, 0.78-0.86), the specificity was 0.79 (95% CI, 0.75-0.82), the positive likelihood ratio was 4.17 (95% CI, 2.6-6.69), and the negative likelihood ratio was 0.25 (95% CI, 0.16-0.39). The area under the summary receiver operating characteristic curve was 0.88 (95% CI, 0.86-0.91), and the Q index was 0.81. The combined diagnostic odds ratio was 17.52 (95% CI, 8.95-34.29).

CONCLUSIONS

Based on the results of the meta-analysis, interleukin-10 is a useful biomarker in the early diagnosis of neonatal sepsis. Its sensitivity, specificity, and diagnostic ability are excellent. However, it needs to be combined with clinical history data for comprehensive judgment and should not be used alone for diagnosis.

The Urosepsis-A Literature Review

Urosepsis is a very serious condition with a high mortality rate. The immune response is in the center of pathophysiology. The therapeutic management of these patients includes surgical treatment of the source of infection, antibiotic therapy and life support. The management of this pathology is multidisciplinary and requires good collaboration between the urology, intensive care, imaging and laboratory medicine departments. An imbalance of pro and anti-inflammatory cytokines produced during sepsis plays an important role in pathogenesis. The study of cytokines in sepsis has important implications for understanding pathophysiology and for development of other therapeutic solutions. If not treated adequately, urosepsis may lead to serious septic complications and organ sequelae, even to a lethal outcome.

The diagnostic accuracy of mid-regional pro-adrenomedullin for sepsis: a systematic review and meta-analysis

BACKGROUND

The incidence and mortality of sepsis are high, and common biomarkers are not perfect. To identify a biomarker with high specificity and sensitivity for sepsis, we evaluated the current literature on the performance of mid-regional pro-adrenomedullin (MR-proADM) in the diagnosis of sepsis.

METHODS

According to appropriate eligibility and exclusion criteria, PubMed, EMBASE, Cochrane Library, China Journal full-text Database, Wanfang Database and Chinese Journal Full Text Database were searched for "Mid-regional proadrenomedullin", "MR-proADM", "Sepsis", "Pyemia", "Pyohemia", "Septicemia" and "Blood poisoning". The publication dates considered for the search were from inception until August 31, 2020. The risk of bias was assessed according to QUADAS-2 criteria.

RESULTS

Eleven studies involving 2038 cases were included. MR-proADM had high sensitivity and specificity in the diagnosis of sepsis, with values of 0.83 [95% CI: (0.79-0.87)] and 0.90 [95% CI: (0.83-0.94)], respectively. The odds ratio of a combined diagnosis was 41.35, and the area under the curve (AUC) was 0.91. The best cut-off value for MR-proADM diagnosis of sepsis is 1-1.5 nmol/L. MRproADM may also have value in distinguishing pathogens and identifying sepsis severity and organ failure.

CONCLUSIONS

MR-proADM is an excellent biomarker for the diagnosis of sepsis with high sensitivity and specificity. The best cut-off value for MR-proADM diagnosis of sepsis is 1-1.5 nmol/L.

PCT Kinetics in the First Week Postburn for Sepsis Diagnosis and Death Prognosis-An Accuracy Study

Despite continuous advances in burn care, sepsis is still the main cause of death in burn patients. Procalcitonin (PCT) has been reported as an accurate sepsis biomarker and also as a fair predictor of death. The aim of this study was to assess PCT kinetics in the first week postburn regarding sepsis diagnosis and death prognosis. Sample included 142 patients with ≥15% TBSA, admitted from January 2011 to December 2014 at Coimbra Burns Unit, Portugal. Sepsis diagnosis was done according to American Burn Association criteria. PCT range and median values in the first 7 days after burns were statistically analyzed for its potential for sepsis diagnosis and death prognosis. A subanalysis was done regarding TBSA, sex, age, and inhalation injury. First week PCT range and median were significant for sepsis diagnosis and death prognosis, but the median area under the curve was greater in the last case. TBSA influenced PCT accuracy, which was greater for TBSA less than 40% either for diagnosis or prognosis. Age was inversely related to the accuracy, being better in younger than 40 years in both cases. PCT diagnostic accuracy was not affected by sex, opposing to the prognostic one which is better in women. Inhalation injury had no effect on diagnostic accuracy, but it happens with prognostic accuracy. PCT levels' variation is related to sepsis evolution and outcome. Its median performs better than its range. Always coupled with clinical examination, monitoring PCT levels kinetics may help early sepsis detection, potentially reducing morbidity and mortality, being also useful for death prognosis.

Best diagnostic accuracy of sepsis combining SIRS criteria or qSOFA score with Procalcitonin and Mid-Regional pro-Adrenomedullin outside ICU

Early diagnosis and treatment significantly reduce sepsis mortality. Currently, no gold standard has been yet established to diagnose sepsis outside the ICU. The aim of the study was to evaluate the diagnostic accuracy of sepsis defined by SIRS Criteria of 1991, Second Consensus Conference Criteria of 2001, modified Second Consensus Conference Criteria of 2001 (obtaining SIRS Criteria and SOFA score), Third Consensus Conference of 2016, in addition to the dosage of Procalcitonin (PCT) and MR-pro-Adrenomedullin (MR-proADM). In this prospective study, 209 consecutive patients with clinical diagnosis of sepsis were enrolled (May 2014-June 2018) outside intensive care unit (ICU) setting. A diagnostic protocol could include SIRS criteria or qSOFA score evaluation, rapid testing of PCT and MR-proADM, and SOFA score calculation for organ failure definition. Using this approach outside the ICU, a rapid diagnostic and prognostic evaluation could be achieved, also in the case of negative SIRS, qSOFA or SOFA scores with high post-test probability to reduce mortality and improve outcomes.

Soluble intercellular adhesion molecule (ICAM)-1 detects invasive fungal infections in patients following liver transplantation

PURPOSE

Despite antifungal prophylaxis, liver transplanted patients are endangered by invasive fungal infections (IFI). Routinely used microbiological procedures are hallmarked by significant weaknesses, which may lead to a delay in antifungal treatment.

METHODS

Culture-based fungal findings, routinely used biomarkers of infection/inflammation (e.g., procalcitonin or C-reactive protein), as well as corresponding plasma concentrations of soluble Intercellular Adhesion Molecule (ICAM)-1 were analysed in 93 patients during a period of 28 days following liver transplantation (LTX).

RESULTS

Plasmatic sICAM-1 was significantly elevated in patients affected by an IFI within the first 28 days in comparison to fungally colonised or unobtrusive LTX patients. sICAM-1 might therefore be helpful for the identification of IFI patients after LTX (e.g., Receiver Operating Characteristic (ROC)-Area Under the Curve (AUC): 0.714 at 14d after LTX). The diagnostic performance of sICAM-1 was further improved by its combined use with different other IFI biomarkers (e.g., midregional proadrenomedullin).

CONCLUSION

The diagnostic deficiencies of routinely used microbiological procedures for IFI detection in patients after LTX may be reduced by plasmatic sICAM-1 measurements. Clinical Trial Notation. German Clinical Trials Register: DRKS00005480.

Diagnostic and prognostic value of procalcitonin and mid-regional pro-adrenomedullin in septic paediatric patients

Early diagnosis of sepsis and its severity stratification at admission is critical to improve patient outcomes and to ensure the optimal use of health care resources. In order to assess the diagnostic potential of mid-regional pro-adrenomedullin (MR-proADM) in septic paediatric patients in comparison with procalcitonin (PCT), and to evaluate the usefulness of a single early determination of MR-proADM as a stratification and severity prediction tool, a prospective observational study was conducted. Seventy-three paediatric patients with a suspicion of sepsis were included. A single blood test was carried out at initial time to analyse infection biomarkers. PCT values were significantly higher in septic patients in comparison with non-septic patients (p = 0.03) with an AUC of 0.748 (p = 0.003). Levels of MR-proADM significantly increased in patients with severe sepsis (p = 0.048), with an AUC of 0.729 (p = 0.013). MR-proADM showed a positive correlation with pSOFA, PRISM III, and PELOD-2 severity scores. Levels of MR-proADM were significantly higher in patients who required vasoactive drugs (p = 0.02) or presented renal dysfunction (p = 0.004).Conclusion: PCT appeared to be superior to MR-proADM in diagnosing sepsis. Determining MR-proADM plasma levels at the initial phase of sepsis could be a useful tool for sepsis stratification and morbidity prediction before organ failure occurs. The present results need to be assessed with larger sample size studies.What is Known:•CRP and PCT are already included in clinical practice to assess sepsis and estimate disease severity, although their sensitivity and specificity are lower than desired.•ADM is a protein that has immune and vascular modulation actions, and its blood levels are increased in adult and paediatric sepsis.•ADM is a promising tool for early diagnosis and prognostic assessment in adult sepsis.What is New:•PCT appeared to be superior to MR-proADM in diagnosing paediatric sepsis.•MR-proADM plasma levels could be a useful tool for paediatric sepsis stratification and morbidity prediction.

The value of biomarker-guided antibiotic therapy

INTRODUCTION

There is an increasing interest to individualize patient management and decisions regarding antibiotic treatment. Biomarkers may provide relevant information for this purpose.

AREAS COVERED

Despite a growing number of clinical trials investigating several biomarkers, there remain open questions regarding the best type of biomarker, timing or frequency of testing, and optimal cutoffs among others. The most promising results in regard to diagnosis of bacterial infection and therapy monitoring are found for procalcitonin (PCT), although some recent trials were not able to validate the promising earlier findings. Furthermore, less specific markers like C-reactive protein (CRP) and new prognostic biomarkers such as proadrenomedullin (MR-proADM) may improve the prognostic assessment of patients and proteomics may help shorten time to microbiological results. The aim of this review is to summarize the current concept of biomarker-guided management and provide an outlook of promising ongoing investigations.

EXPERT OPINION

'Antibiotic stewardship' is complex and needs more than just the measurement of one single biomarker. However, when integrated into the context of a thorough clinical examination, standard blood parameters and a well done risk stratification by clinical scores such as the SOFA-score, biomarkers have great potential to improve the diagnostic and prognostic assessment of patients.

Biomarkers of sepsis: time for a reappraisal

INTRODUCTION

Sepsis biomarkers can have important diagnostic, therapeutic, and prognostic functions. In a previous review, we identified 3370 references reporting on 178 different biomarkers related to sepsis. In the present review, we evaluate the progress in the research of sepsis biomarkers.

METHODS

Using the same methodology as in our previous review, we searched the PubMed database from 2009 until September 2019 using the terms "Biomarker" AND "Sepsis." There were no restrictions by age or language, and all studies, clinical and experimental, were included.

RESULTS

We retrieved a total of 5367 new references since our previous review. We identified 258 biomarkers, 80 of which were new compared to our previous list. The majority of biomarkers have been evaluated in fewer than 5 studies, with 81 (31%) being assessed in just a single study. Apart from studies of C-reactive protein (CRP) or procalcitonin (PCT), only 26 biomarkers have been assessed in clinical studies with more than 300 participants. Forty biomarkers have been compared to PCT and/or CRP for their diagnostic value; 9 were shown to have a better diagnostic value for sepsis than either or both of these biomarkers. Forty-four biomarkers have been evaluated for a role in answering a specific clinical question rather than for their general diagnostic or prognostic properties in sepsis.

CONCLUSIONS

The number of biomarkers being identified is still increasing although at a slower rate than in the past. Most of the biomarkers have not been well-studied; in particular, the clinical role of these biomarkers needs to be better evaluated.

How biomarkers can improve pneumonia diagnosis and prognosis: procalcitonin and mid-regional-pro-adrenomedullin

Aim: The diagnostic and prognostic role of procalcitonin (PCT) and mid-regional-pro-adrenomedullin (MR-proADM) were investigated in patients with pneumonia. Material & methods: A total of 168 and 77 patients with pneumonia enrolled in two different hospital settings, an internal medicine unit and an emergency unit were included in the study. PCT and MR-proADM plasma concentrations and pneumonia severity index score were measured. Median values were compared by Mann–Whitney’s test. Receiver operating characteristic analysis and rank correlation were used to define the diagnostic and prognostic accuracy. Results: PCT confirmed the diagnostic role at values 0.08–0.10 ng/ml and MR-proADM the prognostic role for severe pneumonia. Significant correlation (p < 0.0001) between MR-proADM and pneumonia severity index score indicated expression of pneumonia severity. Conclusion: This combination of biomarkers presents a high positive predictive value in pneumonia diagnosis and prognosis.

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.

Biomarkers of Sepsis and Bloodstream Infections: The Role of Procalcitonin and Proadrenomedullin With Emphasis in Patients With Cancer

Sepsis and bloodstream infections remain a leading cause of death in immunocompromised patients with cancer. The management of these serious infections consist of empiric use of antimicrobial agents which are often overused. Procalcitonin and proadrenomedullin are biomarkers that have been extensively evaluated in the general populations but with little emphasis in the population immunocompromised patients with cancer, where they may have promising roles in the management of febrile patients. In this review, we summarize the available evidence of the potential role of these available biomarkers in guiding antimicrobial therapy to optimize the use of resources in the general patient population. Special emphasis is given to the role of these 2 biomarkers in the immunocompromised and critically ill patients with cancer, highlighting the distinctive utility of each.

Biomarkers and clinical scores to identify patient populations at risk of delayed antibiotic administration or intensive care admission

BACKGROUND

The performance of blood biomarkers (mid-regional proadrenomedullin (MR-proADM), procalcitonin (PCT), C-reactive protein (CRP), and lactate) and clinical scores (Sequential Organ Failure Assessment (SOFA), National Early Warning Score (NEWS), and quick SOFA) was compared to identify patient populations at risk of delayed treatment initiation and disease progression after presenting to the emergency department (ED) with a suspected infection.

METHODS

A prospective observational study across three EDs. Biomarker and clinical score values were calculated upon presentation and 72 h, and logistic and Cox regression used to assess the strength of association. Primary outcomes comprised of 28-day mortality prediction and delayed antibiotic administration or intensive care (ICU) admission, whilst secondary outcomes identified subsequent disease progression.

RESULTS

Six hundred eighty-four patients were enrolled with hospitalisation, ICU admission, and infection-related 28-day mortality rates of 72.8%, 3.4%, and 4.4%, respectively. MR-proADM and NEWS had the strongest association with hospitalisation and the requirement for antibiotic administration, whereas MR-proADM alone had the strongest association with ICU admission (OR [95% CI]: 5.8 [3.1 - 10.8]) and mortality (HR [95% CI]: 3.8 [2.2 - 6.5]). Patient subgroups with high MR-proADM concentrations (≥ 1.77 nmol/L) and low NEWS (< 5 points) values had significantly higher rates of ICU admission (8.1% vs 1.6%; p < 0.001), hospital readmission (18.9% vs. 5.9%; p < 0.001), infection-related mortality (13.5% vs. 0.2%; p < 0.001), and disease progression (29.7% vs. 4.9%; p < 0.001) than corresponding patients with low MR-proADM concentrations. ICU admission was delayed by 1.5 [0.25 - 5.0] days in patients with high MR-proADM and low NEWS values compared to corresponding patients with high NEWS values, despite similar 28-day mortality rates (13.5% vs. 16.5%). Antibiotics were withheld in 17.4% of patients with high MR-proADM and low NEWS values, with higher subsequent rates of ICU admission (27.3% vs. 4.8%) and infection-related hospital readmission (54.5% vs. 14.3%) compared to those administered antibiotics during ED treatment.

CONCLUSIONS

Patients with low severity signs of infection but high MR-proADM concentrations had an increased likelihood of subsequent disease progression, delayed antibiotic administration or ICU admission. Appropriate triage decisions and the rapid use of antibiotics in patients with high MR-proADM concentrations may constitute initial steps in escalating or intensifying early treatment strategies.

Procalcitonin and MR-Proadrenomedullin Combination with SOFA and qSOFA Scores for Sepsis Diagnosis and Prognosis: A Diagnostic Algorithm

PURPOSE

The third Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) defined sepsis as an organ dysfunction consequent to infection. A Sequential Organ Failure Assessment (SOFA) score at least 2 identifies sepsis. In this study, procalcitonin (PCT) and midregional pro-adrenomedullin (MR-proADM) were evaluated along with SOFA and quick SOFA (qSOFA) scores in patients with sepsis or septic shock.

METHODS

A total of 109 septic patients and 50 patients with noninfectious disease admitted at the Department of Internal Medicine and General Surgery of the University Hospital Campus Bio-Medico of Rome were enrolled. PCT and MR-proADM were measured with immunoluminometric assays (Brahms, Hennigsdorf, Germany). Data were analyzed with receiver-operating characteristic (ROC) curve analysis, likelihood ratios, and Mann-Whitney U test using MedCalc 11.6.1.0 package.

RESULTS

At ROC curve analysis, PCT showed the highest area under the curve and positive likelihood ratio values of 27.42 in sepsis and 43.62 in septic shock. MR-proADM and SOFA score showed a comparable performance. In septic shock, lactate showed the most accurate diagnostic ability. In sepsis, the best combination was PCT with MR-proADM with a posttest probability of 0.988. Based upon these results, an algorithm for sepsis and septic shock diagnosis has been developed. MR-proADM, SOFA, and qSOFA scores significantly discriminated survivors from nonsurvivors.

CONCLUSIONS

PCT and MR-proADM test combination represent a good tool in sepsis diagnosis and prognosis suggesting their inclusion in the diagnostic algorithm besides SOFA and qSOFA scores. Furthermore, MR-proADM as marker of organ dysfunction, with a turn around time of about 30 min, has the advantage to be more objective and rapid than SOFA score.

New approaches for the detection of invasive fungal diseases in patients following liver transplantation-results of an observational clinical pilot study

PURPOSE

Despite antifungal prophylaxis following liver transplantation (LTX), patients are at risk for the development of subsequent opportunistic infections, such as an invasive fungal disease (IFD). However, culture-based diagnostic procedures are associated with relevant weaknesses.

METHODS

Culture and next-generation sequencing (NGS)-based fungal findings as well as corresponding plasma levels of ß-D-glucan (BDG), galactomannan (GM), interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), interleukin (IL)-2, -4, -6, -10, -17A and mid-regional proadrenomedullin (MR-proADM) were evaluated in 93 patients at 6 consecutive time points within 28 days following LTX.

RESULTS

A NGS-based diagnostic approach was shown to be suitable for the early identification of fungal pathogens in patients following LTX. Moreover, MR-proADM and IL-17A in plasma proved suitable for the identification of patients with an IFD.

CONCLUSION

Plasma measurements of MR-proADM and IL-17A as well as a NGS-based diagnostic approach were shown to be attractive methodologies to attenuate the weaknesses of routinely used culture-based diagnostic procedures for the determination of an IFD in patients following LTX. However, an additional confirmation within a larger multicenter trial needs to be recommended.

TRIAL REGISTRATION

German Clinical Trials Register: DRKS00005480 .

Infection markers as predictors of Bacteremia in an Intensive Care Unit: A prospective study

Objective:

Although several biomarkers have been evaluated for the diagnosis and prognosis of sepsis, the gold standard biomarker has not yet been found. We aimed to evaluate the diagnostic value of neutrophil-to-lymphocyte count ratio (NLCR), neopterin, pro-adrenomedullin (pro-ADM) and the other infection markers to predict bacteremia in patients with SIRS, sepsis and severe sepsis/septic shock.

Methods:

A prospective cohort study was conducted on septic patients in a tertiary referral hospital between December 2014- July 2015. A total of 156 patients diagnosed with SIRS, sepsis and severe sepsis/septic shock in Anesthesia intensive care unit (ICU) were included in the study.

Results:

A total of 156 patients who had been diagnosed as SIRS(10.9%), sepsis (44.2%) and severe sepsis/septic shock (44.9%) were included. Positive blood cultures were obtained in 64 patients. NLCR, neopterin and pro-ADM levels were insignificant in predicting bacteremia (p>0.05). The mortality rate was significantly higher in bacteremic sepsis (43.9%) compared to non-bacteremic patients (20.8%) (p=0.001). Only procalcitonin levels were significant predictor of mortality (p<0.001).

Conclusion:

NLCR, CRP, procalcitonin, neopterin and pro-ADM levels were insignificant in diagnosis of bacteremia in critically ill patients. The gold standard method in predicting bacteremia is still blood culture positivity.

Prognostic value of serum proadrenomedullin in catheter-related bloodstream infection in the intensive care unit: A prospective observational study

Patients with catheter-related bloodstream infection (CRBSI) have a poor prognosis. Proadrenomedullin (pro-ADM) has emerged as a valuable marker of sepsis. The potential role of pro-ADM in predicting the prognosis of CRBSI was evaluated. We enrolled 25 CRBSI patients and pro-ADM level was measured within 24 hours after each admission. Survival was assessed after 28 days. Among 25 patients with CRBSI, 14 patients survived. Pro-ADM in survivors was significantly lower than that in non-survivors (3.71 ± 1.30 vs 5.58 ± 1.18 nmol/L). The area under the curve (AUC) for pro-ADM was 0.87 (95% CI 0.68-0.97) with a cut-off value of 4.67 nmol/L, providing sensitivity of 85.7% and specificity of 81.8%. The AUCs for PCT, WBC, and CRP were 0.76 (95% CI 0.55-0.90), 0.72 (95% CI 0.50-0.88), and 0.69 (95% CI 0.48-0.86), respectively. Kaplan-Meier survival curves showed pro-ADM ≥ 4.67 nmol/L was associated with higher mortality (log-rank p = 0.001). Moreover, the pro-ADM level was significantly higher in patients with septic shock than those without shock (5.44 ± 1.17 vs 3.54 ± 1.18nmol/L). The mortality of patients with septic shock was higher than that of patients without shock (69.2% vs 16.7%, P = .008). In conclusion, pro-ADM could be used as a prognostic marker of CRBSI in critically ill patients.

Plasma levels of mid-regional pro-adrenomedullin in sepsis are associated with risk of death

BACKGROUND

Identifying Intensive Care Unit (ICU) patients with sepsis and predicting the risk of death are unmet clinical needs.

METHODS

Prospective observational single-center study of 120 consecutive ICU patients with suspected severe sepsis at Jerez Hospital. Epidemiological, clinical, laboratory data and MR-proADM, Procalcitonin (PCT) and C-reactive protein (CRP) levels were recorded at ICU admission and follow-up.

RESULTS

At ICU discharge, 104 patients were diagnosed with severe sepsis and 39 died. Plasma MR-proADM was highly indicative of sepsis: 4.05 nmol/L vs. of 0.309 nmol/L (P<0.001), with area under the ROC curve (AUC-ROC) was 0.947. At 48 hours following admission, the median MR-proADM levels in surviving sepsis patients fell to 1.65 nmol/L but remained higher in the non-survivors (2.475 nmol/L) (P=0.04). On day 5 the levels fell to 1.36 nmol/L in surviving sepsis patients vs. 3.42 nmol/L in the non-survivors (P<0.001). On day 5 the survivors showed greater MR-proADM clearance (62.7% vs. 21.2%). The AUC-ROC on day 5 was 0.825, PCT 0.725 and CRP 0.700. The AUC-ROC to MR-proADM clearance on day 5 was 0.734. In a multivariable model, MR-proADM levels at 48 hours and on day 5 and clearance on day 5 following admission were statistically significant predictive factors of mortality.

CONCLUSIONS

In clinical practice, in ICU patients admitted with SIRS and organ dysfunction, an MR-proADM cut-off point of 1.425 nmol/L helps to identify those with sepsis. An MR-proADM value above 5.626 nmol/L 48 hours after admission was associated with a high risk of death.

Mid-Regional Pro-Adrenomedullin (MR-proADM) as a Biomarker for Sepsis and Septic Shock: Narrative Review

Early identification and diagnosis of sepsis and septic shock is vitally important; despite appropriate management, mortality and morbidity rates remain high. For this reason, many biomarkers and screening systems have been investigated in accordance with the precision medicine concept. A narrative review was conducted to assess the role of mid-regional pro-adrenomedullin (MR-proADM) as a biomarker for sepsis and septic shock. Relevant studies were collected via an electronic PubMed, Web of Science, and The Cochrane Library search. The review focused on both diagnosis and prognosis in patients with sepsis and septic shock and specifically in subpopulations of patients with sepsis and septic shock with burns or malignant tumors. No exclusion criteria regarding age, sex, intensive care unit admission, follow-up duration, or co morbidities were used so as to maximize sensitivity and due to lack of randomized controlled trials, opinion paper and reviews were also included in this review. A total of 22 studies, one opinion paper, and one review paper were investigated. MR-proADM levels were found to be useful in assessing patients’ initial evolution and become even more useful during follow-up with increased area under curve values in the mortality prognosis by exceeding values of 0.8 in the data shown in several studies. These results also improve along with other biomarkers or severity scores and especially correlate with the organ failure degree. The results of this study indicate that MR-proADM is a good biomarker for the diagnosis and prognosis of sepsis and septic shock patients as well as for organ failure. Although several publications have discussed its role as a biomarker for pneumonia, its value as a biomarker for sepsis and septic shock should now be assessed in randomized controlled trials and more collaborative prospective studies with larger patient samples.

Diagnostic and prognostic value of proadrenomedullin in neonatal sepsis

Purpose

Sepsis is a major cause of neonatal morbidity and mortality. Early diagnosis is a major problem because of the lack of specific clinical signs. Therefore, a reliable diagnostic marker is needed to guide the use of antimicrobial agents. The objective of our study was to assess the value of proadrenomedullin (pro-ADM) in establishing the diagnosis and evaluating the prognosis of neonatal sepsis.

Methods

This study enrolled 60 newborn infants with sepsis proven with positive blood cultures and 30 healthy neonates. Complete blood count, C-reactive protein levels, and pro-ADM levels were obtained from all neonates.

Results

The pro-ADM levels were significantly higher (14.39±0.75 nmol/L) in the sepsis group than in the control group (3.12±0.23 nmol/L). The optimal cutoff value for pro-ADM was 4.3 nmol/L, with a sensitivity of 93.3% and a specificity of 86.7%. The pro-ADM levels were also higher in nonsurvivors (P=0.001).

Conclusion

Pro-ADM can be used as a reliable biomarker for neonatal sepsis. High pro-ADM levels were associated with mortality and could be an early indicator of disease outcome.

The role of procalcitonin in the diagnosis of bacterial infection after major abdominal surgery: Advantage from daily measurement

Postsurgical infections represent an important cause of morbidity after abdominal surgery. The microbiological diagnosis is not achieved in at least 30% of culture with consequent worsening of patient outcome. In this study, procalcitonin measurement, during the first 3 days after abdominal surgery, has been evaluated for the early diagnosis of postsurgical infection.Ninety consecutive patients subjected to major abdominal surgery at the University Campus Bio-Medico of Rome, have been included. PCT concentrations were measured by time-resolved amplified cryptate emission (TRACE) assay at admission and at the first, second, and third day after surgery. PCT levels were compared using the Mann-Whitney test and by ANOVA test for variance analysis. Receiver operating characteristic (ROC) analysis was performed to define the diagnostic ability of PCT in case of postsurgical infections.PCT values resulted significantly different between patients developing or not developing postsurgical infections. PCT >1.0 ng/mL at first or second day after surgery and >0.5 ng/mL at third day resulted diagnostic for infectious complication, whereas a value <0.5 ng/mL at the fifth day after surgery was useful for early and safety discharge of patients.In conclusion, PCT daily measurement could represent a useful diagnostic tool improving health care in the postsurgical period following major abdominal surgery and should be recommended.

Immune-Response Patterns and Next Generation Sequencing Diagnostics for the Detection of Mycoses in Patients with Septic Shock-Results of a Combined Clinical and Experimental Investigation

Fungi are of increasing importance in sepsis. However, culture-based diagnostic procedures are associated with relevant weaknesses. Therefore, culture- and next-generation sequencing (NGS)-based fungal findings as well as corresponding plasma levels of β-d-glucan, interferon gamma (INF-γ), tumor necrosis factor alpha (TNF-α), interleukin (IL)-2, -4, -6, -10, -17A, and mid-regional proadrenomedullin (MR-proADM) were evaluated in 50 septic patients at six consecutive time points within 28 days after sepsis onset. Furthermore, immune-response patterns during infections with Candida spp. were studied in a reconstituted human epithelium model. In total, 22% (n = 11) of patients suffered from a fungal infection. An NGS-based diagnostic approach appeared to be suitable for the identification of fungal pathogens in patients suffering from fungemia as well as in patients with negative blood cultures. Moreover, MR-proADM and IL-17A in plasma proved suitable for the identification of patients with a fungal infection. Using RNA-seq., adrenomedullin (ADM) was shown to be a target gene which is upregulated early after an epithelial infection with Candida spp. In summary, an NGS-based diagnostic approach was able to close the diagnostic gap of routinely used culture-based diagnostic procedures, which can be further facilitated by plasmatic measurements of MR-proADM and IL-17A. In addition, ADM was identified as an early target gene in response to epithelial infections with Candida spp.

The Use of Procalcitonin (PCT) for Diagnosis of Sepsis in Burn Patients: A Meta-Analysis

The continuous development of resuscitation techniques and intensive care reduced the mortality rate induced by the initial shock in burn patients and, currently, infections (especially sepsis) are the main causes of mortality of these patients. The misuse of antimicrobial agents is strongly related to antimicrobial and adverse patient outcomes, development of microbial resistance and increased healthcare-related costs. To overcome these risks, antimicrobial stewardship is mandatory and biomarkers are useful to avoid unnecessary medical prescription, to monitor antimicrobial therapy and to support the decision of its stop. Among a large array of laboratory tests, procalcitonin (PCT) emerged as the leading biomarker to accurately and time-effectively indicate the presence of systemic infection. In the presence of systemic infection, PCT blood levels undergo a sudden and dramatic increase, following the course of the infection, and quickly subside after the control of the septic process. This work is a meta-analysis on PCT performance as a biomarker for sepsis. This meta–analysis showed that overall pooled area under the curve (AUC) is 0.83 (95% CI = 0.76 to 0.90); the estimated cut-off is 1.47 ng/mL. The overall sepsis effect in PCT levels is significant and strong (Cohen's d is 2.1 and 95% CI = 1.1 to 3.2). This meta–analysis showed PCT may be considered as a biomarker with a strong diagnostic ability to discriminate between the septic from the non-septic burn patients. Thus, this work encourages the determination of PCT levels in clinical practice for the management of these patients, in order to timely identify the susceptibility to sepsis and to initiate the antimicrobial therapy, improving the patients’ outcomes.

New role of biomarkers: mid-regional pro-adrenomedullin, the biomarker of organ failure

Mid-regional pro-adrenomedullin (MR-proADM) has a good biomarker profile: its half-life is several hours, and its plasma concentrations can be determined in clinical practice, it is essentially irrelevant, but proportionally represents the levels and activity of adrenomedullin (ADM). ADM synthesis is widely distributed in tissues, including bone, adrenal cortex, kidney, lung, blood vessels and heart. Its fundamental biological effects include vasodilator, positive inotropic, diuretic, natriuretic and bronchodilator. It has been described high levels in septic patients, interacting directly with the relaxation of vascular tone, triggering hypotension of these patients. It is also found high levels in other diseases such as hypertension, heart failure, respiratory failure, renal failure, cirrhosis and cancer. MR-proADM has been identified as a prognostic marker, stratifying the mortality risk in patients with sepsis in emergency department (ED) and ICU. Evolutionary MR-proADM levels and clearance marker to the 2nd-5th days of admission help to determine the poor performance and the risk of mortality in patients with severe sepsis admitted to the ICU. The MR-proADM levels are more effective than procalcitonin (PCT) and C-reactive protein (CRP) levels to determine an unfavorable outcome and the risk of mortality in patients with sepsis admitted to the ICU. It has also proved useful in patients diagnosed with organ dysfunction of infectious etiology. MR-proADM levels are independent of the germ conversely it is related to the magnitude of organ failure and therefore severity. We consider advisable incorporating the MR-proADM the panel of biomarkers necessary for the diagnosis and treatment of critically ill patients admitted to the ICU with severe sepsis. The combined PCT and MR-proADM levels could represent a valid tool in the clinical practice to timely identify patients with bacterial infections and guide the diagnosis and treatment of sepsis and septic shock.

Procalcitonin as diagnostic marker of infection in solid tumors patients with fever

In oncologic patients fever is a non-specific clinical marker of different clinical settings. Procalcitonin (PCT) seems to be the most promising infection marker. We aimed to define the potential role of PCT as an earlier diagnostic marker in patients with fever and solid tumor. This retrospective study enrolled 431 patients. All of them performed hemoculture (HE) and basal PCT assessment (reference laboratory cut-off: ≤0.5 or >0.5 ng/dL) before starting antibiotic therapy. Gram positive (G+), negative (G−) or Fungi infection were detected. A statistically significant difference in PCT levels between patients with positive and negative HE was observed (P < 0.0001). Moreover comparing PCT values in patients with positive and negative HE, we obtain in the positive HE subpopulation an AUC of 0.7 and a cut-off of 1.52 ng/dL reached high sensitivity (61.6%) and specificity (70.1%). Using this last cut-off, instead of the normal reference value, we achieve a risk reduction to overestimate an infection status of 23.4%. We support the clinic usefulness of serum PCT dosage in febrile advanced solid tumor patients. A PCT cut-off of 1.52 ng/dL could be helpful in the management of the antibiotic therapy preventing delays of oncologic treatments.

Biomarker kinetics in the prediction of VAP diagnosis: results from the BioVAP study

Background

Prediction of diagnosis of ventilator-associated pneumonia (VAP) remains difficult. Our aim was to assess the value of biomarker kinetics in VAP prediction.

Methods

We performed a prospective, multicenter, observational study to evaluate predictive accuracy of biomarker kinetics, namely C-reactive protein (CRP), procalcitonin (PCT), mid-region fragment of pro-adrenomedullin (MR-proADM), for VAP management in 211 patients receiving mechanical ventilation for >72 h. For the present analysis, we assessed all (N = 138) mechanically ventilated patients without an infection at admission. The kinetics of each variable, from day 1 to day 6 of mechanical ventilation, was assessed with each variable’s slopes (rate of biomarker change per day), highest level and maximum amplitude of variation (Δ^max).

Results

A total of 35 patients (25.4 %) developed a VAP and were compared with 70 non-infected controls (50.7 %). We excluded 33 patients (23.9 %) who developed a non-VAP nosocomial infection. Among the studied biomarkers, CRP and CRP ratio showed the best performance in VAP prediction. The slope of CRP change over time (adjusted odds ratio [aOR] 1.624, confidence interval [CI]_95% [1.206, 2.189], p = 0.001), the highest CRP ratio concentration (aOR 1.202, CI_95% [1.061, 1.363], p = 0.004) and Δ^max CRP (aOR 1.139, CI_95% [1.039, 1.248], p = 0.006), during the first 6 days of mechanical ventilation, were all significantly associated with VAP development. Both PCT and MR-proADM showed a poor predictive performance as well as temperature and white cell count.

Conclusions

Our results suggest that in patients under mechanical ventilation, daily CRP monitoring was useful in VAP prediction.

Trial registration NCT02078999

Electronic supplementary material

The online version of this article (doi:10.1186/s13613-016-0134-8) contains supplementary material, which is available to authorized users.

Procalcitonin, MR-Proadrenomedullin, and Cytokines Measurement in Sepsis Diagnosis: Advantages from Test Combination

BACKGROUND

Elevated cytokines levels correlate with sepsis severity and mortality but their role in the diagnosis is controversial, whereas Procalcitonin (PCT) has been largely used. Recently, the mid-regional proadrenomedullin (MR-proADM) has been combined with PCT for diagnosis optimization. In this study the combined measurement of PCT, MR-proADM, and cytokines in patients with sepsis was evaluated.

METHODS

One hundred and four septic patients and 101 controls were enrolled. Receiver operating characteristic (ROC) analysis and multiple logistic regression were used to evaluate applicant markers for sepsis diagnosis. Markers with best Odds Ratio (OR) were combined, and the posttest probability and a composite score were computed.

RESULTS

Based upon ROC curves analysis, PCT, MR-proADM, IL-6, IL-10, TNF-α, and MCP-1 were considered applicant for sepsis diagnosis. Among these PCT, MR-proADM , IL-6, and TNF-α showed the best OR. A better posttest probability was found with the combination of PCT with MR-proADM and PCT with IL-6 or TNF-α compared to the single marker. A composite score of PCT, MR-proADM, and TNF-α showed the best ROC curve in the early diagnosis of sepsis.

CONCLUSION

The combination of PCT with other markers should expedite diagnosis and treatment of sepsis optimizing clinical management.

Antibiotic Discontinuation Rates Associated with Positive Respiratory Viral Panel and Low Procalcitonin Results in Proven or Suspected Respiratory Infections

INTRODUCTION

The differentiation of viral from bacterial pneumonia is important in determining whether antibiotics are appropriate for treatment of these infections. Advances in diagnostic technologies such as respiratory panels (RP) utilizing polymerase chain reactions to detect viruses and determination of procalcitonin (PCT) concentrations may aid in this differentiation. However, some studies have shown limited impact for this purpose and thus continuation of antibiotics despite results suggesting viral infection. Our objective was to characterize clinician-prescribing behavior at our institution once RP and/or PCT results were known and suggestive of a viral respiratory infection.

METHODS

This retrospective analysis was based upon records of hospitalized patients in whom proven or possible respiratory infections as indicated by RP testing, respiratory bacterial culture or International Statistical Classification of Diseases and Related Health Problems 9th revision codes for acute infectious respiratory illness was documented. Patients evaluated were required to have a RP or PCT within the first 72 h of presentation. Drug orders were evaluated for discontinuation of antibiotic therapy within 48 h of a procalcitonin of <0.25 μg/mL, a positive viral RP result, or both.

RESULTS

Of 4869 patients with PCT and/or RP results, 2031 were included. PCT and RP testing were obtained in 503 and 1823 patients, respectively, with 295 patients having both. Results of these tests suggested 789 patients were potential candidates for antibiotic avoidance. These included 219 with a PCT <0.25 μg/mL, 601 with a positive viral RP result, and 31 with both. Antibiotics were administered to 307 patients (39%) within the first 72 h. In these, antibiotics were discontinued within 48 h of laboratory results availability.

CONCLUSION

These results suggest that positive viral RP and low PCT results are infrequently associated with discontinuation of antibiotic therapy in proven or possible respiratory infections at our institution. Direct interventions with clinicians are likely needed to correct this behavior and decrease unnecessary antibiotic use.

Prognostic value of pro-adrenomedullin, procalcitonin and C-reactive protein in predicting outcome of febrile urinary tract infection

Bacterial infections such as febrile urinary tract infection (fUTI) may run a complicated course that is difficult to foretell on clinical evaluation only. Because the conventional biomarkers erythrocyte sedimentation rate (ESR), leucocyte count, C-reactive protein (CRP) and procalcitonin (PCT) have a limited role in the prediction of a complicated course of disease, a new biomarker-plasma midregional pro-adrenomedullin (MR-proADM)-was evaluated in patients with f UTI. We conducted a prospective multicentre cohort study including consecutive patients with f UTI at 35 primary-care centres and eight emergency departments. Clinical and microbiological data were collected and plasma biomarker levels were measured at presentation to the physician. Survival was assessed after 30 days. Of 494 fUTI patients, median age was 67 (interquartile range 49-78) years, 40% were male; two-thirds of them had significant co-existing medical conditions. Median MR-proADM level was 1.42 (interquartile range 0.67-1.57) nM; significantly elevated MR-proADM levels were measured in patients with bacteraemia, those admitted to the intensive care unit, and in 30-day and 90-day non-survivors, compared with patients without these characteristics. The diagnostic accuracy for predicting 30-day mortality in fUTI, reflected by the area-under-the-curve of receiver operating characteristics were: MR-proADM 0.83 (95% CI 0.71-0.94), PCT 0.71 (95% CI 0.56-0.85); whereas CRP, ESR and leucocyte count lacked diagnostic value in this respect. This study shows that MR-proADM assessed on first contact predicts a complicated course of disease and 30-day mortality in patients with fUTI and in this respect has a higher discriminating accuracy than the currently available biomarkers ESR, CRP, PCT and leucocyte count.

High serum trypsin levels and the -409 T/T genotype of PRSS1 gene are susceptible to neonatal sepsis

Neonatal sepsis remains an important and common cause of morbidity and mortality among newborn infants, especially in developing countries. The aim of the present study was to determine whether serum trypsin levels and genotypes of cationic trypsinogen (PRSS1) gene could be served as markers for predicting neonatal sepsis. The serum trypsin levels and genotypes of PRSS1 were examined in both 50 infants with infection during neonatal period and 56 healthy neonates as controls. The infected infants were further subdivided into infants with sepsis group (n=18) and infected infants without sepsis (n=32). The genotype of PRSS1 was analyzed by direct sequencing, and the serum trypsin level was measured by immunoassay. It showed that the median value of serum trypsin was significantly higher in infected infants (31.90 ng/mL) than in controls (12.85 ng/mL; P=0.030). More importantly, sepsis subgroup (50.95 ng/mL) had significantly higher median serum trypsin than infected infants without sepsis subgroup (19.10 ng/mL) and controls (12.85 ng/mL) (P=0.015 and P=0.002, respectively). Additionally, the median serum trypsin levels were found significantly higher in infants who had T/T (37.90 ng/mL) genotype of PRSS1 compared with those who had C/T genotype (12.80 ng/mL; P=0.005). This study suggested that serum trypsin and rs10273639 C/T of PRSS1 were revealed to be novel markers for predicting neonatal sepsis.

Host response biomarkers in the diagnosis of sepsis: a general overview

Critically ill patients who display a systemic inflammatory response syndrome (SIRS) are prone to develop nosocomial infections. The challenge remains to distinguish as early as possible among SIRS patients those who are developing sepsis. Following a sterile insult, damage-associated molecular patterns (DAMPs) released by damaged tissues and necrotic cells initiate an inflammatory response close to that observed during sepsis. During sepsis, pathogen-associated molecular patterns (PAMPs) trigger the release of host mediators involved in innate immunity and inflammation through identical receptors as DAMPs. In both clinical settings, a compensatory anti-inflammatory response syndrome (CARS) is concomitantly initiated. The exacerbated production of pro- or anti-inflammatory mediators allows their detection in biological fluids and particularly within the bloodstream. Some of these mediators can be used as biomarkers to decipher among the patients those who developed sepsis, and eventually they can be used as prognosis markers. In addition to plasma biomarkers, the analysis of some surface markers on circulating leukocytes or the study of mRNA and miRNA can be helpful. While there is no magic marker, a combination of few biomarkers might offer a high accuracy for diagnosis.

Neutrophil CD64 expression as a diagnostic marker for sepsis in adult patients: a meta-analysis

INTRODUCTION

Neutrophil CD64 (nCD64) expression appears to be a promising marker of bacterial infections. The aim of this meta-analysis was to assess the accuracy of nCD64 expression for the diagnosis of sepsis in critically ill adult patients.

METHODS

We systematically searched PubMed, Embase, ISI Web of Knowledge, and the Cochrane Library for literature published between database inception and 19 May 2014, as well as reference lists of identified primary studies. Studies were included if they included assessment of the accuracy of nCD64 expression for sepsis diagnosis in adult patients and provided sufficient information to construct a 2×2 contingency table.

RESULTS

A total of 8 studies comprising 1986 patients fulfilled the inclusion criteria for the final analysis. The pooled sensitivity and specificity were 0.76 (95 % confidence interval [CI], 0.73-0.78) and 0.85 (95 % CI, 0.82-0.87), respectively. The positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio were 8.15 (95 % CI, 3.82-17.36), 0.16 (95 % CI, 0.09-0.30), and 60.41 (95 % CI, 15.87-229.90), respectively. The area under the summary receiver operating characteristic curve of nCD64 expression with Q* value were 0.95 (Q* =0.89).

CONCLUSIONS

On the basis of our meta-analysis, nCD64 expression is a helpful marker for early diagnosis of sepsis in critically ill patients. The results of the test should not be used alone to diagnose sepsis, but instead should be interpreted in combination with medical history, physical examination, and other test results.

Diagnostic and prognostic role of procalcitonin (PCT) and MR-pro-Adrenomedullin (MR-proADM) in bacterial infections

Rapid diagnosis of bacterial infections is crucial for adequate antibiotic treatment. Serum molecules such as Procalcitonin (PCT) have been used as biomarkers of infection. Recently, the mid-regional pro-Adrenomedullin (MR-proADM) has been evaluated in combination with PCT for sepsis diagnosis. The diagnostic role of PCT and MR-proADM both in sepsis and in localized infections together with their contribution to effective antibiotic therapy has been evaluated. One hundred and eighty-two patients with bacterial infection has been enrolled: PCT and MR-proADM were measured at admission (T = 0), at 12-24 h (T = 1) and in the third or fifth day of antibiotic therapy (T = 3-5). ROC curve (receiver operating characteristic) and post-test probability were calculated. MR-proADM increased with the severity of the infection. PCT resulted significantly higher in sepsis than localized infection. After antibiotic therapy, PCT significantly decreased in localized respiratory infections and in sepsis, while MR-proADM decreased significantly after antibiotic therapy only in patients with severe sepsis/septic shock. The threshold values of PCT and MR-proADM were >0.1 ng/mL and >0.8 nmol/L, respectively. The combined use of PCT and MR-proADM increased the post-test probability of the diagnosis of bacterial infections compared to PCT alone. In conclusion, PCT and MR-proADM combination improves the diagnosis of bacterial infection and contribute to prognosis and antibiotic therapy effectiveness.

Biomarkers for sepsis

Bloodstream infections are a major concern because of high levels of antibiotic consumption and of the increasing prevalence of antimicrobial resistance. Bacteraemia is identified in a small percentage of patients with signs and symptoms of sepsis. Biomarkers are widely used in clinical practice and they are useful for monitoring the infectious process. Procalcitonin (PCT) and C-reactive protein (CRP) have been most widely used, but even these have limited abilities to distinguish sepsis from other inflammatory conditions or to predict outcome. PCT has been used to guide empirical antibacterial therapy in patients with respiratory infections and help to determine if antibacterial therapy can be stopped. New biomarkers such as those in this review will discuss the major types of biomarkers of bloodstream infections/sepsis, including soluble triggering receptor expressed on myeloid cells-1 (sTREM-1), soluble urokinase-type plasminogen receptor (suPAR), proadrenomedullin (ProADM), and presepsin.