Procalcitonin as a prognostic and diagnostic tool for septic complications after major trauma

Fracture related infection and sepsis in orthopedic trauma: A review

Trauma is a leading cause of death in the United States for people under 45. Amongst trauma-related injuries, orthopedic injuries represent a significant component of trauma-related morbidity. In addition to the potential morbidity and mortality secondary to the specific traumatic injury or injuries sustained, sepsis is a significant cause of morbidity and mortality in trauma patients as well, and infection related to orthopedic trauma can be especially devastating. Therefore, infection prevention and early recognition of infections is crucial to lowering morbidity and mortality in trauma. Risk factors for fracture-related infection include obesity, tobacco use, open fracture, and need for flap coverage, as well as fracture of the tibia and the degree of contamination. Timely administration of prophylactic antibiotics for patients presenting with open fractures has been shown to decrease the risk of fracture-related infection, and in patients that do experience sepsis from an orthopedic injury, prompt source control is critical, which may include the removal of implanted hardware in infections that occur more than 6 weeks from operative fixation. Given that orthopedic injury constitutes a significant proportion of traumatic injuries, and will likely continue to increase in number in the future, surgeons caring for patients with orthopedic trauma must be able to promptly recognize and manage sepsis secondary to orthopedic injury.

Bloodstream infection: derivation and validation of a reliable and multidimensional prognostic score based on a machine learning model (BLISCO)

BACKGROUND

A bloodstream infection (BSI) prognostic score applicable at the time of blood cultures collection is currently missing.

OBJECTIVES

We aimed to derivate and validate ta machine learning model-based BSIs prognostic scores, to predict 14 and 30-day in-hospital mortality (BLISCO 14d-30d).

METHODS

4327 patients with BSIs were included, divided in a derivation (80%) and a validation dataset (20%). Forty-two variables among host-related, demographic, epidemiological, clinical, laboratory extracted from the electronic health records were analyzed. Logistic regression was chosen for predictive scoring after testing multiple machine learning models. Accuracy was assessed using sensitivity, specificity, and predictive values.

RESULTS

The 14-day mortality model included age, body temperature, blood urea nitrogen, respiratory insufficiency, platelets count, high-sensitive C-reactive protein and consciousness status: a score of ≥ 6 was correlated to a 14-day mortality rate of 15% with a sensitivity of 0.742, a specificity of 0.727 and an AUC 0.783. The 30-day mortality model further included cardiovascular diseases: a score of ≥ 6 predicting 30-day mortality rate of 15% with a sensitivity of 0.691 a specificity of 0.699 and an AUC 0.697.

CONCLUSIONS

A quick and easy-to-assess mortality score could represent a valid support for prognosis assessment and resources prioritizing for patients with BSIs not admitted in ICU.

Development and validation of a nomogram for predicting gram-negative bacterial infections in patients with peritoneal dialysis-associated peritonitis

Background

This study aimed to develop a nomogram for predicting gram-negative bacterial (GNB) infections in patients with peritoneal dialysis-associated peritonitis (PDAP) to identify patients at high risk for GNB infections.

Methods

In this investigation, hospitalization information was gathered retrospectively for patients with PDAP from January 2016 to December 2021. The concatenation of potential biomarkers obtained by univariate logistic regression, LASSO analysis, and RF algorithms into multivariate logistic regression was used to identify confounding factors related to GNB infections, which were then integrated into the nomogram. The concordance index (C-Index) was utilized to assess the precision of the model's predictions. The area under the curve (AUC) and decision curve analysis (DCA) was used to assess the predictive performance and clinical utility of the nomogram.

Results

The final study population included 217 patients with PDAP, and 37 (17.1%) patients had gram-negative bacteria due to dialysate effluent culture. After multivariate logistic regression, age, procalcitonin, and hemoglobin were predictive factors of GNB infections. The C-index and bootstrap-corrected index of the nomogram for estimating GNB infections in patients were 0.821 and 0.814, respectively. The calibration plots showed good agreement between the predictions of the nomogram and the actual observation of GNB infections. The AUC of the receiver operating characteristic curve was 0.821, 95% CI: 0.747-0.896, which indicates that the model has good predictive accuracy. In addition, the DCA curve showed that the nomogram had a high clinical value in the range of 1%-94%, which further demonstrated that the nomogram could accurately predict GNB infection in patients with PDAP.

Conclusions

We have created a new nomogram for predicting GNB infections in patients with PDAP. The nomogram model may improve the identification of GNB infections in patients with PDAP and contribute to timely intervention to improve patient prognosis.

Procalcitonin and Pediatric Traumatic Brain Injury: Differentiating Neuro-Storming From Infection

INTRODUCTION

Recurrent febrile episodes represent a diagnostic challenge in the pediatric traumatic brain injury (TBI) population as they may indicate presence of infection versus sterile neuro-storming. Procalcitonin (PCT) is a promising biomarker used in pediatric sepsis; however, data are limited regarding use in TBI. We hypothesized PCT helps discern neuro-storming from sepsis in children with TBI.

MATERIALS AND METHODS

A single-institution retrospective review (2014-2021) identified pediatric patients (aged 0-18 y) with moderate-to-severe TBI and intensive care unit admission > 2 d. Patients with multiple febrile events who underwent infectious evaluation including cultures and PCT drawn within 48 h of fever were included. Demographics, vital signs, infectious biomarkers including PCT, and culture data were captured. Univariate and multivariate analyses were performed to determine variables associated with culture positive status.

RESULTS

One hundred and fifty six patients were admitted to the intensive care unit with moderate-to-severe TBI during the study period. Eighty five patients (54%) experienced recurrent febrile episodes. Twenty four (28%) met inclusion criteria, undergoing 32 total infectious workups. Twenty one workups were culture-positive (66%) in a total of 18 patients. Median PCT levels were not statistically different between culture-positive and culture-negative workups (P = 0.94). In multivariate modeling, neither PCT [odds ratio 0.89 (confidence interval: 0.75-1.05)] nor temperature [odds ratio 7.34 (confidence interval: 0.95-57.16)] correlated with positive bacterial cultures.

CONCLUSIONS

In this small pilot analysis, recurrent febrile episodes were common and PCT did not correlate with sepsis or neuro-storming in pediatric TBI patients. Prospective protocols are needed to better understand the utility of PCT and identify predictors of bacterial infection to improve early diagnosis of sepsis in this population.

Early changes in white blood cell, C-reactive protein and procalcitonin levels in children with severe multiple trauma

BACKGROUND

To analyze early changes in white blood cells (WBCs), C-reactive protein (CRP) and procalcitonin (PCT) in children with multiple trauma, before secondary inflammation develops.

METHODS

This single-center retrospective study collected data from patients with blunt traumatic injury admitted to the pediatric intensive care unit (PICU). According to the prognostic outcome of 28 d after admission to the PICU, patients were divided into survival group (n=141) and non-survival group (n=36). Characteristics between the two groups were compared. Receiver operation characteristic (ROC) curve analysis was conducted to evaluate the capacity of different biomarkers as predictors of mortality.

RESULTS

The percentages of children with elevated WBC, CRP, and PCT levels were 81.36%, 31.07%, and 95.48%, respectively. Patients in the non-survival group presented a statistically significantly higher injury severity score (ISS) than those in the survival group: 37.17±16.11 vs. 22.23±11.24 (t=6.47, P<0.01). WBCs were also higher in non-survival group than in the survival group ([18.70±8.42]×10⁹/L vs. [15.89±6.98] ×10⁹/L, t=2.065, P=0.040). There was no significant difference between the survival and non-survival groups in PCT or CRP. The areas under the ROC curves of PCT, WBC and ISS for predicting 28-day mortality were 0.548 (P=0.376), 0.607 (P=0.047) and 0.799 (P<0.01), respectively.

CONCLUSIONS

Secondary to multiple trauma, PCT levels increased in more patients, even if their WBC and CRP levels remained unchanged. However, early rising WBC and ISS were superior to PCT at predicting the mortality of multiple trauma patients in the PICU.

Soluble CD14 Subtype in Peripheral Blood is a Biomarker for Early Diagnosis of Sepsis

OBJECTIVE

To study the value of serum soluble CD14 subtype (sCD14-ST) in early diagnosis of sepsis.

METHODS

Seventy-two patients were diagnosed with systemic inflammatory response syndrome, sepsis, or septic shock. Peripheral blood was collected at 0, 12, 24, and 48 hours after admission to the hospital. Levels of sCD14-ST, procalcitonin (PCT), hypersensitive C-reactive protein (CRP), and white blood cells (WBC) were determined.

RESULTS

Levels of sCD14-ST in the patients with septic shock were higher than those in the other patients (P < .01) and peaked at 48 h. PCT and CRP levels were similar in the patients at admission but increased by 5 times to 10 times in the next 48 h, especially in the patients with septic shock. WBC levels remained high and did not change dramatically. Receiver operating characteristic analysis revealed that the area under the curve, sensitivity, and specificity values of sCD14-ST to diagnose sepsis were much higher than those of the other markers.

CONCLUSION

Compared with PCT, CRP, and WBC, sCD14-ST is a better biomarker for the early diagnosis of sepsis.

Gene Expression-Based Diagnosis of Infections in Critically Ill Patients-Prospective Validation of the SepsisMetaScore in a Longitudinal Severe Trauma Cohort

OBJECTIVES

Early diagnosis of infections is pivotal in critically ill patients. Innovative gene expression-based approaches promise to deliver precise, fast, and clinically practicable diagnostic tools to bedside. This study aimed to validate the SepsisMetaScore, an 11-gene signature previously reported by our study group, in a representative longitudinal cohort of trauma patients.

DESIGN

Prospective observational cohort study.

SETTING

Surgical ICUs of the University Medical Center Goettingen, Germany.

PATIENTS

Critically ill patients with severe traumatic injuries.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Paired box gene (PAXgene) RNA blood tubes were drawn at predefined time points over the course of disease. The performance of the SepsisMetaScore was tested using targeted polymerase chain reaction and compared with Procalcitonin using area under the receiver operating characteristics analyses. The SepsisMetaScore showed significant differences between infected and noninfected patients (n = 52). It was able to accurately discriminate infectious from noninfectious acute inflammation with an area under the receiver operating characteristics of 0.92 (95% CI, 0.85-0.99) and significantly outperformed Procalcitonin (area under the receiver operating characteristics curve = 0.53; 95% CI, 0.42-0.64) early in the course of infection (p = 0.014).

CONCLUSIONS

We demonstrated the clinical utility for diagnosis of infections with higher accuracy using the SepsisMetaScore compared with Procalcitonin in a prospective cohort of severe trauma patients. Future studies should assess whether the SepsisMetaScore may substantially improve clinical practice by accurate differentiation of infections from sterile inflammation and identification of patients at risk for sepsis. Our results support further investigation of the SepsisMetaScore for the development of tailored precision treatment of critically ill patients.

The role of procalcitonin in reducing antibiotics across the surgical pathway

Procalcitonin (PCT) is widely considered as a highly sensitive biomarker of bacterial infection, offering general and emergency surgeons a key tool in the management of surgical infections. A multidisciplinary task force of experts met in Bologna, Italy, on April 4, 2019, to clarify the key issues in the use of PCT across the surgical pathway. The panelists presented the statements developed for each of the main questions regarding the use of PCT across the surgical pathway. An agreement on the statements was reached by the Delphi method, and this document reports the executive summary of the final recommendations approved by the expert panel.

Procalcitonin in special patient populations: Guidance for antimicrobial therapy

PURPOSE

Procalcitonin (PCT) is an endogenous hormone that increases reliably in response to bacterial infection, and measurement of serum PCT levels is recommended to help guide antimicrobial therapy. The utility of PCT assessment in special patient populations (eg, patients with renal dysfunction, cardiac compromise, or immunocompromised states and those undergoing acute care surgery) is less clear. The evidence for PCT-guided antimicrobial therapy in special populations is reviewed.

SUMMARY

In the presence of bacterial infection, nonneuroendocrine PCT is produced in response to bacterial toxins and inflammatory cytokines, resulting in markedly elevated levels of serum PCT. Cytokine induction in nonbacterial inflammatory processes activated by acute care surgery may alter the interpretation of PCT levels. The reliability of PCT assessment has also been questioned in patients with renal dysfunction, cardiac compromise, or immunosuppression. In many special populations, serum PCT may be elevated at baseline and increase further in the presence of infection; thus, higher thresholds for diagnosing infection or de-escalating therapy should be considered, although the optimal threshold to use in a specific population is unclear. Procalcitonin-guided antimicrobial therapy may be recommended in certain clinical situations.

CONCLUSION

Procalcitonin may be a reliable marker of infection even in special populations with baseline elevations in serum PCT. However, due to unclear threshold values and the limited inclusion of special populations in relevant clinical trials, PCT levels should be considered along with clinical criteria, and antibiotics should never be initiated or withheld based on PCT values alone. Procalcitonin measurement may have a role in guiding de-escalation of antibiotic therapy in special populations; however, the clinician should be aware of disease states and concomitant therapies that may affect interpretation of results.

LDH, CRP and ALB predict nucleic acid turn negative within 14 days in symptomatic patients with COVID-19

Aims

To search for biochemical indicators that can identify symptomatic patients with COVID-19 whose nucleic acid could turn negative within 14 days, and assess the prognostic value of these biochemical indicators in patients with COVID-19.

Patients and methods

We collected the clinical data of patients with COVID-19 admitted to our hospital, by using logistic regression analysis and AUC curves, explored the relationship between biochemical indicators and nucleic acid positive duration, the severity of COVID-19, and hospital stay respectively.

Results

A total of two hundred and thirty-three patients with COVID-19 were enrolled in the study. We found patients whose nucleic acid turned negative within 14 days had lower LDH, CRP and higher ALB (P < 0.05). ROC curve results indicated that lower LDH, TP, CRP and higher ALB predicted the nucleic acid of patients turned negative within 14 days with statistical significance(P < 0.05), AST, LDH, CRP and PCT predicted the severe COVID-19 with statistical significance, and CRP predicted hospital stay >31days with statistical significance (P < 0.05). After verification, the probability of nucleic acid turning negative within 14 days in patients with low LDH (<256 U/L), CRP (<44.5 mg/L) and high ALB (>35.8 g/L) was about 4 times higher than that in patients with high LDH, CRP and low ALB (P < 0.05).

Conclusions

LDH, CRP and ALB are useful prognostic marker for predicting nucleic acid turn negative within 14 days in symptomatic patients with COVID-19.

Procalcitonin kinetics early after severe burn injury and its value in diagnosis of sepsis

PURPOSE

To investigate the clinical significance of procalcitonin (PCT) kinetics early after burn and the perioperative period, and to assess its diagnostic performance for sepsis in major burn patients.

METHODS

This retrospective study on major burn patents (≥40% total body surface area) admitted from 2014 to 2019 was conducted in Southwest Hospital, Chongqing, China. A total of 321 patients were included. The kinetics of PCT was analyzed during the 1st week after burn, the perioperative period, and at the onset of clinical suspected sepsis.

RESULTS

Serum PCT concentration rose immediately after burn injury. Factors associated with increased PCT level in the 1st week after burn include greater burn area (>70% TBSA) and lower age (≤14 years). Correlations between PCT kinetics after burn and the risk of early development of sepsis and mortality were observed. At the onset of sepsis, serum PCT increased significantly compared to its basal level in the 48 h before diagnosis. The area under the receiver operating characteristics curve of PCT concentration and its kinetic changes was 0.788 and 0.826, respectively. PCT kinetics showed better accuracy than PCT concentration in discrimination of Gram-positive sepsis. The optimal diagnostic thresholds for PCT concentration and its kinetics were 1.41 ng/mL, and a 1.34-fold elevation compared to the baseline level.

CONCLUSIONS

PCT kinetics in the early stage after burn was a prognostic factor for sepsis and mortality among major burn patients. Serum PCT levels could be a diagnostic biomarker for sepsis in major burn patients.

Laboratory Markers in the Management of Pediatric Polytrauma: Current Role and Areas of Future Research

Severe trauma is the most common cause of mortality in children and is associated with a high socioeconomic burden. The most frequently injured organs in children are the head and thorax, followed by the extremities and by abdominal injuries. The efficient and early assessment and management of these injuries is essential to improve patients' outcome. Physical examination as well as imaging techniques like ultrasound, X-ray and computer tomography are crucial for a valid early diagnosis. Furthermore, laboratory analyses constitute additional helpful tools for the detection and monitoring of pediatric injuries. Specific inflammatory markers correlate with post-traumatic complications, including the development of multiple organ failure. Other laboratory parameters, including lactate concentration, coagulation parameters and markers of organ injury, represent further clinical tools to identify trauma-induced disorders. In this review, we outline and evaluate specific biomarkers for inflammation, acid-base balance, blood coagulation and organ damage following pediatric polytrauma. The early use of relevant laboratory markers may assist decision making on imaging tools, thus contributing to minimize radiation-induced long-term consequences, while improving the outcome of children with multiple trauma.

Early Differential Value of Plasma Presepsin on Infection of Trauma Patients

OBJECTIVE

Early differential diagnosis of an infection in a trauma patient is likely to have a significant influence on the prognosis. In the present study, we evaluated the early differential value of plasma presepsin, procalcitonin (PCT), C-reactive protein (CRP), and white blood cells (WBCs) on infection in trauma patients.

METHODS

Trauma patients were divided into noninfected (n = 89) and infected trauma groups (n = 68); healthy adult volunteers (n = 60) and patients having sterile surgery (n = 60) were enrolled as the controls. Plasma presepsin, PCT, CRP, and WBC counts were measured and the injury severity score (ISS) was calculated.

RESULTS

Plasma presepsin levels within the first 3 d of admission were only significantly increased in the infected trauma group, but not in the noninfected trauma and sterile groups. This indicated that presepsin might have an ability to differentiate the infection in trauma patients; however, plasma PCT, CRP, and WBCs were significantly increased in both the infected and noninfected trauma patients. Binary logistic regression analysis showed that only increased plasma presepsin, PCT, and ISS were significantly associated with an increased likelihood of infection in trauma patients. Both presepsin and PCT were valuable for diagnosing infection; presepsin had a higher area under the curve than PCT.

CONCLUSION

Presepsin might be a superior biomarker for early differentiation of infection in trauma patients; however, trauma stress elevates PCT, CRP, and WBCs even in the absence of infection; therefore, caution is advised when using these indicators to diagnose infection.

A 2020 review on the role of procalcitonin in different clinical settings: an update conducted with the tools of the Evidence Based Laboratory Medicine

Biomarkers to guide antibiotic treatment decisions have been proposed as an effective way to enhancing a more appropriate use of antibiotics. As a biomarker, procalcitonin (PCT) has been found to have good specificity to distinguish bacterial from non-bacterial inflammations. Decisions regarding antibiotic use in an individual patient are complex and should be based on the pre-test probability for bacterial infection, the severity of presentation and the results of PCT serum concentration. In the context of a high pre-test probability for bacterial infections and/or a high-risk patient with sepsis, monitoring of PCT over time helps to track the resolution of infection and decisions regarding early stop of antibiotic treatment. As outlined by the Evidence Based Laboratory Medicine (EBLM), not only the pre-test probability but also the positive likelihood ratio influence the performance of a test do be really diagnostic. This aspect should be taken into account in the interpretation of the results of clinical trials evaluating the performance of PCT in guiding antibiotic therapy.

The prognostic value of serum procalcitonin measurements in critically injured patients: a systematic review

Background

Major trauma is associated with high incidence of septic complications and multiple organ dysfunction (MOD), which markedly influence the outcome of injured patients. Early identification of patients at risk of developing posttraumatic complications is crucial to provide early treatment and improve outcomes. We sought to evaluate the prognostic value of serum procalcitonin (PCT) levels after trauma as related to severity of injury, sepsis, organ dysfunction, and mortality.

Methods

We searched PubMed, MEDLINE, EMBASE, the Cochrane Database, and references of included articles. Two investigators independently identified eligible studies and extracted data. We included original studies that assessed the prognostic value of serum PCT levels in predicting severity of injury, sepsis, organ dysfunction, and mortality among critically injured adult patients.

Results

Among 2015 citations, 19 studies (17 prospective; 2 retrospective) met inclusion criteria. Methodological quality of included studies was moderate. All studies showed a strong correlation between initial PCT levels and Injury Severity Score (ISS). Twelve out of 16 studies demonstrated significant elevation of initial PCT levels in patients who later developed sepsis after trauma. PCT level appeared a strong predictor of MOD in seven out of nine studies. While two studies did not show association between PCT levels and mortality, four studies demonstrated significant elevation of PCT levels in non-survivors versus survivors. One study reported that the PCT level of ≥ 5 ng/mL was associated with significantly increased mortality (OR 3.65; 95% CI 1.03–12.9; p = 0.04).

Conclusion

PCT appears promising as a surrogate biomarker for trauma. Initial peak PCT level may be used as an early predictor of sepsis, MOD, and mortality in trauma population.

Procalcitonin for predicting catheter-associated bloodstream infection: A meta-analysis

OBJECTIVE

The predictive accuracies of procalcitonin (PCT) in the diagnosis of catheter-associated bloodstream infection (CABSI) vary widely. This meta-analysis aimed to explore the predictive value of PCT for CABSI.

METHODS

We searched PubMed, EMBase, Web of Science, ScienceDirect, Cochrane Library, and studies published up to 10 March 2019. Odds ratios (ORs) with 95% confidence intervals (95%CIs) were calculated to evaluate PCT predictive value using Stata 14.0 software.

RESULTS

The meta-analysis was composed of 7 studies, consisting of 347 subjects. Pooled analysis demonstrated that a high PCT was significantly correlated with CABSI (pooled OR = 23.36, 95%CI 12.43-43.91, P < .001) and medium heterogenicity (I = 36.9%, P = .147). The pooled sensitivity and specificity were 85% (95%CI 0.76-0.91) and 89% (95%CI 0.68-0.97), respectively. Although Begg funnel plot (P = .007) indicated the presence of publication bias among the included studies, the stability of the pooled outcomes was verified by the trim-and-fill method. Furthermore, sensitivity analyses did not show important differences in effect estimation.

CONCLUSION

PCT is an effective predictor of CABSI. However, high-quality randomized controlled trials are needed to determine whether PCT could predict CABSI.

The use of APACHE II, SOFA, SAPS 3, C-reactive protein/albumin ratio, and lactate to predict mortality of surgical critically ill patients: A retrospective cohort study

Several prognostic indices have been employed to predict the outcome of surgical critically ill patients. Among them, acute physiology and chronic health evaluation (APACHE) II, sequential organ failure assessment (SOFA) and simplified acute physiology score (SAPS 3) are widely used. It seems that biological markers such as C-reactive protein (CRP), albumin, and blood lactate levels correlate with the degree of inflammation during the immediate postoperative phase and could be used as independent predictors. The objective of this study is to compare the different predictive values of prognostic indices and biological markers in the outcome of 847 surgical patients admitted to the intensive care unit (ICU) in the postoperative phase.The patients were divided into survivors (n = 765, 57.4% males, age 61, interquartile range 51-71) and nonsurvivors (n = 82, 57.3% males, age 70, interquartile range 58-79). APACHE II, APACHE II death probability (DP), SOFA, SAPS 3, SAPS 3 DP, CRP, albumin, and lactate were recorded on ICU admission (first 24 hours). The area under the ROC curve (AUROC) and 95% confidence interval (95% CI) were used to measure the index accuracy to predict mortality.The AUROC and 95% CI for APACHE II, APACHE II DP, SOFA, SAPS 3, SAPS 3 DP, CRP/albumin ratio, CRP, albumin, and lactate were 0.850 (0.824-0.873), 0.855 (0.829-0.878), 0.791 (0.762-0.818), 0.840 (0.813-0.864), 0.840 (0.813-0.864), 0.731 (0.700-0.761), 0.708 (0.676-0.739), 0.697 (0.665-0.728), and 0.601 (0.567-0.634), respectively. The ICU and overall in-hospital mortality were 6.6 and 9.7%, respectively. The APACHE II, APACHE II DP, SAPS 3, SAPS 3 DP, and SOFA scores showed a better performance than CRP/albumin ratio, CRP, albumin, or lactate to predict in-hospital mortality of surgical critically ill patients.Even though all indices were able to discriminate septic from nonseptic patients, only APACHE II, APACHE II DP, SOFA and to a lesser extent SAPS 3, SAPS 3 DP, and blood lactate levels could predict in the first 24-hour ICU admission surgical patients who have survived sepsis.

Ability of serum procalcitonin to distinguish focus of infection and pathogen types in patients with bloodstream infection

Background

Serum procalcitonin (PCT) is a widely recognized inflammatory marker which can distinguish systemic bacterial infection from other types of infections. The ability of PCT levels to distinguish different pathogens from different focus of infection is contradictory.

Methods

This study included 551 patients with bloodstream infection (BSI) diagnosed with positive blood culture (BC) during Jan 2013 and May 2018. The patients were divided into two groups with or without definite focus of infection. In this study, we analyzed PCT levels induced by Gram-positive bacteria, Gram-negative bacteria and fungal infection. Relationship of time between PCT peak and BC collection, and the impact of antibiotics usage on PCT peak distribution were examined.

Results

For patients without definite focus of infection, the serum PCT values of Gram-negative bacteria were higher than that of Gram-positive bacteria (P<0.05). A cut-off value of 7.54 ng/mL for PCT showed a sensitivity of 88.3%. For patients with definite focus of infection, the serum PCT values of Gram-negative bacteria were significantly higher than Gram-positive bacteria in patients with lower respiratory tract (P=0.003), abdominal (P=0.039), urinary tract infection (P=0.025), but not in patients with upper respiratory tract infection (P=0.664). The PCT values between multidrug-resistant organism (MDRO) and sensitive bacteria were not statistically significant (P>0.05) among all patients. Moreover, among patients who use antibiotics before BC collection, the longer antibiotics used, the higher trend of the proportion for PCT peak distribution after BC collection. The higher proportion of antibiotics combined before BC collection, the lower proportion of PCT peak distribution appeared before BC collection, and the higher the proportion of PCT peak distribution appeared after BC collection.

Conclusions

PCT value is determined by many factors. PCT value is related to not only Gram-positive bacteria or Gram-negative bacteria, but also related to specific pathogens, and specific of infection sites etc. The use of Antibiotics is also an important factor of PCT value.

Procalcitonin Is a Prognostic Marker of Hospital Outcomes in Patients with Critical Limb Ischemia and Diabetic Foot Infection

AIM

To evaluate the prognostic role of procalcitonin (PCT) in patients with diabetic foot infection (DFI) and critical limb ischemia (CLI).

MATERIALS AND METHODS

The study group was composed of diabetic patients with DFI and CLI. All patients were treated according to a preset limb salvage protocol which includes revascularization, wound debridement, antibiotic therapy, and offloading. Inflammatory markers, including PCT, were evaluated at admission. Only positive values of PCT, greater than 0.5 ng/ml, were considered. Hospital outcomes were categorized as limb salvage (discharge with preserved limb), major amputation (amputation above the ankle), and mortality.

RESULTS

Eighty-six patients were included. The mean age was 67.3 ± 11.4 years, 80.7% were male, 95.1% had type 2 diabetes, and the mean diabetes duration was 20.5 ± 11.1 with a mean HbA1c of 67 ± 16 mmol/mol. 66/86 (76.8%) of patients had limb salvage, 7/86 (8.1%) had major amputation, and 13/86 (15.1%) died. Patients with positive PCT baseline values in comparison to those with normal values showed a lower rate of limb salvage (30.4 versus 93.6%, p = 0.0001), a higher rate of major amputation (13 versus 6.3%, p = 0.3), and a higher rate of hospital mortality (56.5 versus 0%, p < 0.0001). At the multivariate analysis of independent predictors found at univariate analysis, positive PCT was an independent predictor of major amputation [OR 3.3 (CI 95% 2.0-5.3), p = 0.0001] and mortality [OR 4.1 (CI 95% 2.2-8.3), p < 0.0001].

DISCUSSION

Positive PCT at admission increased the risk of major amputation and mortality in hospital patients with DFI and CLI.

Splenectomy modulates early immuno-inflammatory responses to trauma-hemorrhage and protects mice against secondary sepsis

In polytrauma patients, the impact of splenectomy is equivocal, ranging from negative to protective. We investigated the impact of splenectomy on immune responses in the 1^st-hit polytrauma alone and on survival in the post-traumatic sepsis (2^nd hit). Female BALB/c mice underwent polytrauma (1^st hit) consisting of either a) TH: femur fracture, hemorrhagic shock or b) TSH: splenectomy, femur fracture, hemorrhagic shock. Additionally, the polytrauma hit was followed by cecal ligation and puncture (CLP) 48 h later and compared to CLP alone. Splenectomy improved the 28-day survival in secondary sepsis to 92% (from 62%), while TH lowered it to 46% (p < 0.05). The improved survival was concurrent with lower release of inflammatory cytokines (IL-6, CXCL-1, MCP-1) and increase of C5a post-CLP. In the polytrauma hit alone, TSH induced stronger neutrophilia (1.9 fold) and lymphocytosis (1.7 fold) when compared to TH mice. Moreover, TSH resulted in a 41% rise of regulatory T-cells and reduced the median fluorescence intensity of MHC-2 on monocytes by 55% within 48 h (p < 0.05). Conversely, leukocyte phagocytic capacity was significantly increased by 4-fold after TSH despite a similar M1/M2 macrophage profile in both groups. Summarizing, splenectomy provoked both immuno-suppressive and immuno-stimulatory responses but was life-saving in secondary sepsis. Additionally, the polytrauma components in 2-hit models should be tested for their effects on outcome; the presumed end-effect of the 1^st hit solely based on the common immuno-inflammatory parameters could be misleading.

Diagnostic and predictive values of procalcitonin in bloodstream infections for nosocomial pneumonia

PURPOSE

We evaluated the diagnostic accuracy of PCT to distinguish between gram-negative (GN) and gram-positive (GP) bloodstream infections nosocomial pneumonia (NP) patients and compared PCT levels with the pneumonia severity index (PSI) for predicting mortality.

METHODS

Data were collected retrospectively for blood culture-positive NP patients between January 2014 and August 2016. PCT levels were compared between patients with GN versus GP infections. Outcome variables included 28- and 60-day mortality.

RESULTS

PCT level was higher in GN infections than in GP infections. PCT could differentiate between GN and GP infections with an AUC value of 0.706. At a PCT cutoff of 5.4 ng/mL, the specificity for GN infections were 80.3%. The AUCs for 28- and 60-day mortality were 0.758 and 0.759 for PSI, and 0.620 and 0.634 for PCT. Serum PCT level was less predictive of mortality in GN NP patients compared with that for GP NP patients. There was a significantly positive correlation between PCT and PSI, and the correlation in GP NP patients was better than that in GN NP patients.

CONCLUSIONS

PCT could differentiate between GN and GP bloodstream infections in patients with NP. However, PCT levels were less predictive of mortality compared with the PSI.

Procalcitonin: Usefulness in Acute Care Surgery and Trauma

BACKGROUND

Procalcitonin (PCT) is a serum biomarker currently suggested by the Surviving Sepsis Campaign to aid in determination of the appropriate duration of therapy in sepsis patients. We review the use of procalcitonin in patients after trauma or acute care surgery.

METHOD

A MEDLINE search via PubMed was performed using the combination of "procalcitonin" and "humans" and "injuries, trauma," "wounds and injuries," or "wounds." Studies of burn patients, children, other biomarkers, and non-acute care surgery were excluded.

RESULTS

Procalcitonin may be useful in identifying infection in trauma and post-operative acute care surgery. However, heterogenity exists among patients, and surgery and trauma alone elevate PCT even in the absence of infection.

CONCLUSIONS

Although trends in PCT concentrations may offer insight, no standard approach can be recommended currently.

Incidence of elevated procalcitonin and presepsin levels after severe trauma: a pilot cohort study

Procalcitonin (PCT) and presepsin (PSEP) are useful biomarkers for diagnosing sepsis; however, elevated PCT and PSEP levels may be observed in conditions other than sepsis. We hypothesised that PCT and PSEP levels could increase after severe traumatic injuries. Trauma patients with an Injury Severity Score of ≥16 from October 2013 to September 2015 were enrolled in our study. We examined PCT and PSEP levels and their positive rates on days 0 and 1. PCT and PSEP levels on days 0 and 1 were compared. Risk factors for increasing sepsis biomarker levels were identified by multivariate logistic regression analyses. In this study, 75 patients were included. PCT levels on days 0 and 1 were 0.1±0.4 and 1.8±6.3 ng/ml, respectively (P=0.02). PSEP levels on days 0 and 1 were 221±261 and 222±207 pg/ml, respectively (P=0.98). As per multivariate logistic regression analyses, packed red blood cell (PRBC) transfusion was the only independent risk factor for higher PCT levels on day 1 (P=0.04). Using PCT to diagnose sepsis in trauma patients on day 1 requires caution. PRBC transfusion was found to be a risk factor for increasing PCT levels. On the other hand, PSEP levels were not affected by trauma during the early phases.

Prognostic Value of Serum Procalcitonin After Orthopedic Surgery in the Elderly Population

Background

Orthopedic surgery is more and more frequent in the older patients and is associated with a high mortality rate. Although serum procalcitonin levels are associated with prognosis in young adults, data are still lacking in the elderly population, and especially after surgery. The main objective of this study was to determine the prognostic value of procalcitonin levels in a large geriatric orthopedic population, and we compared it with clinical variables and biomarkers.

Methods

This is a prospective study including patients admitted in our dedicated geriatric postoperative unit, after orthopedic surgery with immediate postoperative measured procalcitonin levels. Collected data included age, sex, medical history, functional status (activities of daily living [ADL]), fracture type, Cumulative Illness Rating scale (CIRS), postoperative complications, and biological data. The primary endpoint was the 30-day mortality.

Results

436 patients (age 85±6 years) were included. Hip fracture surgery was the most frequent (n = 310; 71%), and the 30-day mortality rate was 6.9%. Compared with C-reactive protein (CRP), albumin, CIRS, and ADL, procalcitonin had the highest area under the receiver operating characteristic curve for predicting 30-day mortality (0.74; 95% CI: 0.70-0.78). Using a cutoff at 1 µg/L, procalcitonin was more specific than CIRS to predict 30-day mortality (92 vs 77%; p < .001). In a multivariable analysis, procalcitonin level higher than 0.39 µg/L is a significant predictor of mortality within 30 days (odds ratio 3.84; 95% CI: 1.61-9.14, p = .002).

Conclusion

Elevated procalcitonin values were strongly and significantly associated with mortality within 30 days in older patients after orthopedic surgery.

Single-blinded, randomized, and controlled clinical trial evaluating the effects of Omega-3 fatty acids among septic patients with intestinal dysfunction: A pilot study

Sepsis is a systemic inflammatory reaction, which is aggravated by aspects of the immune response that are thought to be inhibited by Omega-3 fatty acids. The aim of the present study was to determine if Omega-3 fatty acid could modulate immunological function and improve survival rate among septic patients with intestinal dysfunction. A total of 48 mechanically ventilated patients with intestinal dysfunction were included in this prospective, randomized and single-blind clinical study. Patients were randomly divided into control (group A) and treatment groups (group B). The treatment protocol for all the participants followed the Sepsis Survival Campaign guidelines, and group B received total parenteral nutrition containing 100 ml of Omega-3 fatty acids (containing 10 g refined fish oil) per day in addition to the standard treatment applied in group A. Group B had a significantly lower mortality rate compared with group A (12.5 vs. 41.7%, P<0.05) during the 28-day follow-up. Group B also had lower Acute Physiology and Chronic Health Evaluation II scores (P<0.05) and lower Marshall scores (P<0.05) at day 7. In addition, group B had a higher ratio of T helper to inducer lymphocytes as well as a higher ratio of CD4 to CD8 lymphocytes (P<0.01 for both) than group A. It was concluded that Omega-3 fatty acids improved T helper/inducer and CD4/CD8 ratios, and may have reduced mortality, among septic patients with intestinal dysfunction.

Thioredoxin a novel biomarker of post-injury sepsis

BACKGROUND

Thioredoxin (TRX), an endogenous anti-oxidant protein induced in inflammatory conditions, has been shown to increase in plasma and to be associated with outcome in septic patients. This biomarker has never been studied in a trauma setting. We hypothesized that TRX would be increased after trauma and associated with post-injury sepsis.

METHODS

Single-centre prospective observational study conducted at the intensive care unit (ICU) at the Karolinska University Hospital, Stockholm, Sweden, a level-1 trauma centre. Eighty-three severely injured trauma patients, 18 years or older, with an ICU stay of three days or more were included. Plasma samples were obtained on day 1 and 3 after informed consent. Clinical, physiological and outcome data were retrieved from the trauma and ICU research registries. Plasma samples were also obtained from 15 healthy subjects. In addition, a standardized porcine trauma model was conducted where a femur fracture followed by a controlled hemorrhage period were inflicted in four pigs.

RESULTS

In pigs, however not significant, there was a continuing increase in plasma-TRX after femur fracture and sequential hemorrhage despite near normalisation of cardiac index and lactate levels. In patients, median injury severity score was 29 and 48 patients developed sepsis during their ICU stay. A three-fold increase in initial TRX was seen in trauma patients when compared to healthy volunteers. Thioredoxin was significantly higher in patients in shock on admission, those subject to massive transfusion and in the most severely injured patients. No difference was seen between survivors and non-survivors. Plasma-TRX on day 1 was significantly increased in patients who later developed post-injury sepsis. In a logistic regression analysis including TRX, C-reactive protein, injury severity, massive transfusion, and admission blood pressure, TRX was the only variable independently associated with post-injury sepsis.

CONCLUSIONS

This study demonstrates that TRX is released into plasma in response to severe trauma and independently associated with post-injury sepsis. The use of TRX as a biomarker in trauma patients needs further evaluation in larger studies.

LEVEL OF EVIDENCE

Retrospective cohort study, level III.

Procalcitonin levels in bloodstream infections caused by different sources and species of bacteria

OBJECTIVE

The aim of this study was to evaluate procalcitonin (PCT) diagnostic accuracy in discriminating gram-negative (GN) from gram-positive (GP) bloodstream infections and determining the relationship between PCT levels, infection sites, and pathogen types.

METHODS

Clinical and laboratory data were collected from patients with blood culture (BC)-positive sepsis between January 2014 and December 2015. PCT levels at different infection sites were compared, as was the presence of GN and GP bloodstream infection. A receiver operating characteristic (ROC) curve was generated to assess diagnostic accuracy.

RESULTS

Of the 486 monomicrobial BCs, 254 (52.26%) were positive for GN bacteria (GNB), and 202 (42.18%) for GP bacteria (GPB). Median PCT levels were higher in BCs positive for GN (2.42ng/ml, IQR: 0.38-15.52) than in those positive for GPB (0.49ng/ml, IQR: 0.13-5.89) (P<0.001). In the ROC analysis to differentiate between GNB and GPB, the area under the curve was 0.628 (95% CI: 0.576-0.679). When the cutoffs for PCT were 10.335 and 15.000ng/ml, the specificity of GNB infection was 80.2% and 84.2%, respectively. PCT levels caused by GNB differed between Escherichia coli and Acinetobacter baumanni/Burkholderia cepacia, Klebsiella pneumonia and Acinetobacter baumanni. PCT levels caused by GPB differed between Staphylococcus epidermidis/Staphylococcus aureus and Staphylococcus hominis/Staphylococcus haemolyticus, Enterococcus faecium and Enterococcus faecalis/S.hominis/S. haemolyticus. Among patients with known infection sites, there were statistical differences in PCT levels between abdominal infection and pneumonia/infective endocarditis, urinary tract infection and pneumonia/catheter-related infection/infective endocarditis.

CONCLUSION

PCT can distinguish between GNB and GPB infection, as well as between different bacterial species and infection sites.

Preoperative oral health care reduces postoperative inflammation and complications in oral cancer patients

The records of 70 patients with oral cancer who were treated at a single institution between 2008 and 2014 were reviewed. The body temperature, white blood cell count, and C-reactive protein (CRP) levels were compared between those who had received preoperative oral care (oral care group) and those who had not received any (non-oral care group). When the patients were divided into those who underwent minimally invasive surgery and those who underwent severely invasive surgery, the mean CRP level in the early postoperative period was lower in the oral care group as compared with the non-oral care group in those who underwent minimally invasive surgery as well as those who underwent severely invasive surgery. However, the mean CRP level was most evidently reduced in the severely invasive group on days 1 and 3-5. However, no significant differences were observed with regard to the percentage of postoperative infectious complications (for example, surgical site infection, anastomotic leak and pneumonia) between the oral care (13.6%) and non-oral care (20.8%) groups, though a reduced prevalence of postoperative complications following preoperative oral care was noted. The results of the present study suggest that preoperative oral care can decrease inflammation during the early postoperative stage in patients with oral cancer who undergo severely invasive surgery.

The Clinical Challenge of Sepsis Identification and Monitoring

Jean-Louis Vincent outlines why combinations of biomarkers will be central to the future of sepsis diagnosis.

Procalcitonin Levels in Survivors and Nonsurvivors of Sepsis: Systematic Review and Meta-Analysis

Procalcitonin (PCT) is an acute-phase reactant that has been used to diagnose and potentially track the treatment of sepsis. Procalcitonin values rise initially as the infection sets in and eventually fall with resolution. Its level has been reported to be significantly higher in potential nonsurvivors of a septic episode than among survivors. However, there is also a significant amount of evidence against this. We thus conducted a meta-analysis to pool data from all the available studies regarding PCT levels in survivors and nonsurvivors of sepsis. An extensive literature search was conducted using the key words "procalcitonin," "sepsis," and "prognosis." The references of the relevant studies were also scanned. The data from the eligible studies were extracted and analyzed for any significant pooled mean difference between survivors and nonsurvivors both on days 1 and 3. The mean difference in the day 1 PCT values between survivors and nonsurvivors was found to be statistically significant (P = 0.02). The mean difference on day 3 was also statistically significant (P = 0.002). However, in a subgroup consisting of studies on patients with severe sepsis and septic shock, day 1 difference was not found to be significant (P = 0.62). We found heterogeneity of 90% in our study population, which decreased to 62% after exclusion of studies conducted in emergency department patients. Procalcitonin levels in early stages of sepsis are significantly lower among survivors as compared with nonsurvivors of sepsis.

Efficacy and safety of procalcitonin guidance in reducing the duration of antibiotic treatment in critically ill patients: a randomised, controlled, open-label trial

BACKGROUND

In critically ill patients, antibiotic therapy is of great importance but long duration of treatment is associated with the development of antimicrobial resistance. Procalcitonin is a marker used to guide antibacterial therapy and reduce its duration, but data about safety of this reduction are scarce. We assessed the efficacy and safety of procalcitonin-guided antibiotic treatment in patients in intensive care units (ICUs) in a health-care system with a comparatively low use of antibiotics.

METHODS

We did a prospective, multicentre, randomised, controlled, open-label intervention trial in 15 hospitals in the Netherlands. Critically ill patients aged at least 18 years, admitted to the ICU, and who received their first dose of antibiotics no longer than 24 h before inclusion in the study for an assumed or proven infection were eligible to participate. Patients who received antibiotics for presumed infection were randomly assigned (1:1), using a computer-generated list, and stratified (according to treatment centre, whether infection was acquired before or during ICU stay, and dependent on severity of infection [ie, sepsis, severe sepsis, or septic shock]) to receive either procalcitonin-guided or standard-of-care antibiotic discontinuation. Both patients and investigators were aware of group assignment. In the procalcitonin-guided group, a non-binding advice to discontinue antibiotics was provided if procalcitonin concentration had decreased by 80% or more of its peak value or to 0·5 μg/L or lower. In the standard-of-care group, patients were treated according to local antibiotic protocols. Primary endpoints were antibiotic daily defined doses and duration of antibiotic treatment. All analyses were done by intention to treat. Mortality analyses were completed for all patients (intention to treat) and for patients in whom antibiotics were stopped while being on the ICU (per-protocol analysis). Safety endpoints were reinstitution of antibiotics and recurrent inflammation measured by C-reactive protein concentrations and they were measured in the population adhering to the stopping rules (per-protocol analysis). The study is registered with ClinicalTrials.gov, number NCT01139489, and was completed in August, 2014.

FINDINGS

Between Sept 18, 2009, and July 1, 2013, 1575 of the 4507 patients assessed for eligibility were randomly assigned to the procalcitonin-guided group (761) or to standard-of-care (785). In 538 patients (71%) in the procalcitonin-guided group antibiotics were discontinued in the ICU. Median consumption of antibiotics was 7·5 daily defined doses (IQR 4·0-12·7) in the procalcitonin-guided group versus 9·3 daily defined doses (5·0-16·6) in the standard-of-care group (between-group absolute difference 2·69, 95% CI 1·26-4·12, p<0·0001). Median duration of treatment was 5 days (3-9) in the procalcitonin-guided group and 7 days (4-11) in the standard-of-care group (between-group absolute difference 1·22, 0·65-1·78, p<0·0001). Mortality at 28 days was 149 (20%) of 761 patients in the procalcitonin-guided group and 196 (25%) of 785 patients in the standard-of-care group (between-group absolute difference 5·4%, 95% CI 1·2-9·5, p=0·0122) according to the intention-to-treat analysis, and 107 (20%) of 538 patients in the procalcitonin-guided group versus 121 (27%) of 457 patients in the standard-of-care group (between-group absolute difference 6·6%, 1·3-11·9, p=0·0154) in the per-protocol analysis. 1-year mortality in the per-protocol analysis was 191 (36%) of 538 patients in the procalcitonin-guided and 196 (43%) of 457 patients in the standard-of-care groups (between-group absolute difference 7·4, 1·3-13·8, p=0·0188).

INTERPRETATION

Procalcitonin guidance stimulates reduction of duration of treatment and daily defined doses in critically ill patients with a presumed bacterial infection. This reduction was associated with a significant decrease in mortality. Procalcitonin concentrations might help physicians in deciding whether or not the presumed infection is truly bacterial, leading to more adequate diagnosis and treatment, the cornerstones of antibiotic stewardship.

FUNDING

Thermo Fisher Scientific.

Procalcitonin in patients with influenza A (H1N1) infection and acute respiratory failure

OBJECTIVE

To verify serum procalcitonin levels of patients with acute respiratory failure secondary to influenza A (H1N1) upon their admission to the Intensive Care Unit and to compare these results to values found in patients with sepsis and trauma admitted to the same unit.

METHODS

Analysis of records of patients infected with influenza A (H1N1) and respiratory failure admitted to the General Intensive Care Unit during in a period of 60 days. The values of serum procalcitonin and clinical and laboratory data were compared to those of all patients admitted with sepsis or trauma in the previous year.

RESULTS

Among patients with influenza A (H1N1) (n = 16), the median serum procalcitonin level upon admission was 0.11 ng/mL, lower than in the sepsis group (p < 0.001) and slightly lower than in trauma patients. Although the mean values were low, serum procalcitonin was a strong predictor of hospital mortality in patients with influenza A (H1N1).

CONCLUSION

Patients with influenza A (H1N1) with severe acute respiratory failure presented with low serum procalcitonin values upon admission, although their serum levels are predictors of hospital mortality. The kinetics study of this biomarker may be a useful tool in the management of this group of patients.

Combined biomarkers discriminate a low likelihood of bacterial infection among surgical intensive care unit patients with suspected sepsis

Among surgical intensive care unit (SICU) patients, it is difficult to distinguish bacterial sepsis from other causes of systemic inflammatory response syndrome (SIRS). Biomarkers have proven useful to identify the presence of bacterial infection. We enrolled a prospective cohort of 69 SICU patients with suspected sepsis and assayed the concentrations of 9 biomarkers (α-2 macroglobulin [A2M], C-reactive protein, ferritin, fibrinogen, haptoglobin, procalcitonin [PCT], serum amyloid A, serum amyloid P, and tissue plasminogen activator) at baseline, 24, 48, and 72hours. Forty-two patients (61%) had bacterial sepsis by chart review. A2M concentrations were significantly lower, and PCT concentrations were significantly higher in subjects with bacterial sepsis at 3 of 4 time points. Using optimal cutoff values, the combination of baseline A2M and 72-hour PCT achieved a negative predictive value of 75% (95% confidence interval, 54-96%). The combination of A2M and PCT discriminated bacterial sepsis from other SIRS among SICU patients with suspected sepsis.

Inflammatory Changes and Coagulopathy in Multiply Injured Patients

Severe tissue trauma leads to an early activation of several danger recognition systems, including the complement and the coagulation system, often resulting in an overwhelming almost synchronic pro- and anti-inflammatory response of the host. Although the immune response is associated with beneficial effects at the site of injury including the elimination of exogenous and endogenous danger molecules as well as the initiation of regenerative processes, an exaggerated systemic inflammatory response significantly contributes to posttraumatic complications such as multiple organ failure (MOF) and early death. Besides pre-existing physical conditions, age, gender, and underlying comorbidities, surgical and anesthesiological management after injury is decisive for outcome. Improvements in surgical intensive care have increased number of patients who survive the initial phase after trauma. However, instead of progressing to normal recovery, patients often pass into persistent inflammation, immunosuppression, and catabolism syndrome (PICS). The characterization and management of PICS will require new strategies for direct monitoring and therapeutic intervention into the patient’s immune function. In this chapter, we describe various factors involved in the inflammatory changes after trauma and aim to understand how these factors interact to progress to systemic inflammation, MOF, and PICS.

The impact of tracheotomy on levels of procalcitonin in patients without sepsis: a prospective study

OBJECTIVE

Procalcitonin is a reliable biomarker of infection and sepsis. We aimed to determine whether tracheotomy influences the procalcitonin concentrations in patients without sepsis and assess whether operative duration and procedure affect the peak procalcitonin level.

METHODS

A total of 38 non-septic patients who required a tracheotomy underwent either a percutaneous dilatational tracheotomy (n=19) or a surgical tracheotomy (n=19). Procalcitonin levels were measured at the beginning of the tracheotomy and at 2 h, 4 h, 8 h, 24 h, 48 h and 72 h after the procedure.

RESULTS

The baseline procalcitonin concentration before the tracheotomy was 0.24 ± 0.13 ng/mL. The postoperative levels increased rapidly, with a 4-fold elevation after 2 h, reaching a peak 4 h later with a 5-fold increase over baseline. Thereafter, the levels gradually returned to 2-fold greater than the baseline level within 72 h. The peak levels of procalcitonin showed a significant positive correlation with operative durations (r=0.710, p<0.001) and procedures (rho=0.670, p<0.001).

CONCLUSION

In patients without sepsis, tracheotomy induces a rapid release of serum procalcitonin, and the operative duration and procedure have significant impacts on the peak procalcitonin levels. Thus, the nonspecific increase in procalcitonin levels following tracheotomy needs to be considered when this measure is used to evaluate infection.

The PRECious trial PREdiction of Complications, a step-up approach, CRP first followed by CT-scan imaging to ensure quality control after major abdominal surgery: study protocol for a stepped-wedge trial

Background

After major abdominal surgery (MAS), 20 % of patients endure major complications, which require invasive treatment and are associated with increased morbidity and mortality. A quality control algorithm after major abdominal surgery aimed at early identification of patients at risk of developing major complications can decrease associated morbidity and mortality. Literature studies show promising results for C-reactive protein (CRP) as an early marker for postoperative complications, however clinical significance has yet to be determined.

Methods

A multicenter, stepped wedge, prospective clinical trial including all adult patients planned to undergo elective MAS. The first period consists of standard postoperative monitoring, which entails on demand additional examinations. This is followed by a period with implementation of postoperative control according to the PRECious protocol, which implicates standardized measurement of CRP levels. If CRP levels exceed 140 mg/L on postoperative day 3,4 or 5, an enhanced CT-scan is performed.

Primary outcome in this study is a combined primary outcome, entailing all morbidity and mortality due to postoperative complications. Complications are graded according to the Clavien-Dindo classification. Secondary outcomes are hospital length of stay, patients reported outcome measures (PROMs) and cost-effectiveness. Data will be collected during admission, three months and one year postoperatively. Approval by the medical ethics committee of the VU University Medical Center was obtained (ID 2015.114).

Discussion

the PRECious trial is a stepped-wedge, multicenter, open label, prospective clinical trial to determine the effect of a standardized postoperative quality control algorithm on postoperative morbidity and mortality, and cost-effectiveness.

Trial registration

www.ClinicalTrials.gov, NCT02102217. Registered 5 February 2015.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-015-0903-y) contains supplementary material, which is available to authorized users.

Procalcitonin ratio and on-demand relaparotomy for septic peritonitis: validation of the focus index (FI)

PURPOSE

Secondary peritonitis remains challenging to manage and some recent evidence suggests that on-demand relaparotomy is more appropriate than planned relaparotomy. This study was designed to validate the predictive power of postoperative procalcitonin (PCT) changes in relation to elimination of the septic abdominal focus.

METHODS

In this prospective trial, postoperative PCT serum levels were monitored in 234 surgical patients with secondary peritonitis. The PCT ratio on postoperative days (PODs) 1 and 2 (focus index; FI) was calculated and correlated with the success of the operation.

RESULTS

A cutoff value of 1.1 was calculated for the FI. Values below 1.1 indicated insufficient elimination of the focus and values above 1.1 correlated with effective treatment. The optimal time for first PCT sampling was found to be 12-24 h after the index operation. After the respective data cleanup, successful elimination of the intraabdominal focus could be confirmed, with a sensitivity of 93 % and a specificity of 71 %.

CONCLUSIONS

The FI is a single parameter-based reliable predictor of successful surgical eradication and strengthens the on-demand relaparotomy concept as the method of choice to treat secondary peritonitis.

Predictive Value of C-Reactive Protein for Major Complications after Major Abdominal Surgery: A Systematic Review and Pooled-Analysis

Background

Early diagnosis and treatment of complications after major abdominal surgery can decrease associated morbidity and mortality. Postoperative CRP levels have shown a strong correlation with complications. Aim of this systematic review and pooled-analysis was to assess postoperative values of CRP as a marker for major complications and construct a prediction model.

Study design

A systematic review was performed for CRP levels as a predictor for complications after major abdominal surgery (MAS). Raw data was obtained from seven studies, including 1427 patients. A logit regression model assessed the probability of major complications as a function of CRP levels on the third postoperative day. Two practical cut-offs are proposed: an optimal cut-off for safe discharge in a fast track protocol and another for early identification of patients with increased risk for major complications.

Results

A prediction model was calculated for major complications as a function of CRP levels on the third postoperative day. Based on the model several cut-offs for CRP are proposed. For instance, a two cut-off system may be applied, consisting of a safe discharge criterion with CRP levels below 75 mg/L, with a negative predictive value of 97.2%. A second cut-off is set at 215 mg/L (probability 20%) and serves as a predictor of complications, indicating additional CT-scan imaging.

Conclusions

The present study provides insight in the interpretation of CRP levels after major abdominal surgery, proposing a prediction model for major complications as a function of CRP on postoperative day 3. Cut-offs for CRP may be implemented for safe early-discharge in a fast-track protocol and, secondly as a threshold for additional examinations, such as CT-scan imaging, even in absence of clinical signs, to confirm or exclude major complications. The prediction model allows for setting a cut-off at the discretion of individual surgeons or surgical departments.

Determination of Factors Affecting Mortality of Patients with Sepsis in a Tertiary Intensive Care Unit

OBJECTIVES

Sepsis is a disease with high mortality that is frequently observed in intensive care units. This study aimed to determine the risk factors affecting mortality of patients with sepsis who were followed up in the intensive care unit (ICU). We aimed to contribute to literature by evaluating the relationship between mortality and pro-brain natriuretic peptide (pro-BNP9), C-reactive protein (CRP), thrombocyte count, Acute Physiology and Chronic Health Evaluation (APACHE) II score, Sequential Organ Failure Assessment (SOFA) score, duration of hospitalization in the intensive care unit, and the presence of multidrug-resistant microorganism.

MATERIAL AND METHODS

Patients hospitalized in ICU because of the diagnosis of sepsis and septic shock between December 2010 and June 2012 were included in this retrospective study.

RESULTS

A total of 141 patients, including 74 male (52.5%) and 67 female (47.5%) patients, were involved in the study, and the median age was 66.8±17.9 years. Sixty-nine patients (48.9%) were discharged from the ICU; however, 72 patients (51.1%) were exitus. Multidrug-resistant microorganism was detected in 34 patients (24.1%). The patients' median SOFA score was 9.16±3.16, median APACHE-II score was 24.9±7.83, and median duration of hospitalization in the ICU was 8.44±11.61 days. It was found that mortality rate significantly increased in patients with the APACHE-II score of 24.5 and over, SOFA score of 8.5 and over, pro BNP value of 7241 ng/L and over, and CRP value of 96.5 mg/dL and over. Mortality rate was detected to be higher in patients undergoing invasive mechanical ventilation than in patients undergoing non-invasive mechanical ventilation. When thrombocyte count and mortality were associated with each other, it was found that the median value was 86000 mg/dL in exitus patients, whereas it was 185000 mg/dL in patients discharged from the ICU.

CONCLUSION

It was revealed that increased APACHE-II score, increased SOFA score, increased pro BNP score, increased CRP, the presence of multidrug-resistant microorganism, and decreased thrombocyte count elevated the rate of mortality. However, no relationship was observed between the duration of hospitalization in the ICU and mortality.

Searching for predictors of surgical complications in critically ill surgery patients in the intensive care unit: a review

We reviewed the use of the levels of C-reactive protein, lactate and procalcitonin and/or the Sequential Organ Failure Assessment score to determine their diagnostic accuracy for predicting surgical complications in critically ill general post-surgery patients. Included were all studies published in PubMed from inception to July 2013 that met the following inclusion criteria: evaluation of the above parameters, describing their diagnostic accuracy and the risk stratification for surgical complications in surgical patients admitted to an intensive care unit. No difference in the Sequential Organ Failure Assessment scores was seen between patients with or without complications. The D-lactate levels were significantly higher in those who developed colonic ischemic complications after a ruptured abdominal aortic aneurysm. After gastro-intestinal surgery, contradictory data were reported, with both positive and negative use of C-reactive protein and procalcitonin in the diagnosis of septic complications. However, in trauma patients, the C-reactive protein levels may help to discriminate between those with and without infectious causes. We conclude that the Sequential Organ Failure Assessment score, lactate concentration and C-reactive protein level have no significant predictive value for early postoperative complications in critically ill post-surgery patients. However, procalcitonin seems to be a useful parameter for diagnosing complications in specific patient populations after surgery and/or after trauma.

Host response biomarkers in sepsis: the role of procalcitonin

Procalcitonin is the prohormone of calcitonin and present in minute quantities in health. However, during infection, its levels rise considerably and are correlated with the severity of the infection. Several assays have been developed for measurement of procalcitonin levels; in this article, we will briefly present the PCT-sensitive Kryptor(®) test (Brahms, Hennigsdorf, Germany), one of the most widely used assays for procalcitonin in recent studies. Many studies have demonstrated the value of procalcitonin levels for diagnosing sepsis and assessing disease severity. Procalcitonin levels have also been successfully used to guide antibiotic administration. However, procalcitonin is not specific for sepsis, and values need to be interpreted in the context of a full clinical examination and the presence of other signs and symptoms of sepsis.

Clinical Applications of Procalcitonin in Pediatrics: An Advanced Biomarker for Inflammation and Infection-Can It Also Be Used in Trauma?

Background. Procalcitonin is a small molecular peptide that has gained increased support as an adjunct diagnostic marker of infection in the adult population; the concordant body of evidence for the use of procalcitonin in pediatric populations is far less complete. Objectives. Our objective is to review the current evidence supporting the utilization of procalcitonin in children in a variety of clinical scenarios including SIRS, sepsis, burns, and trauma and to identify existing knowledge gaps. Methods. A thorough review of the literature was performed utilizing PubMed. We focused on using meta-analysis from adult populations to review current practices in interpretation and methodology and find concordant pediatric studies to determine if the same applications are validated in pediatric populations. Results. Current evidence supports the usage of procalcitonin as both a sensitive and a specific marker for the differentiation of systemic inflammatory response syndrome from sepsis in pediatrics with increased diagnostic accuracy compared to commonly used biomarkers including complete blood counts and C-reactive protein. Conclusions. Although the body of evidence is limited, initial observations suggest that procalcitonin can be used in pediatric trauma and burn patients as both a prognostic and a diagnostic marker, aiding in the identification of infection in patients with extensive underlying inflammation.

Prediction of sepsis in trauma patients

Trauma is one of the leading causes of death worldwide. Approximately 39.5% of deaths occur in the hospital, and the mortality rate of delayed death caused by septic complications is still high. Early prediction of the development of sepsis can help promote early intervention and treatment for patients and contribute to improving patient outcomes. Thus so far, biomarkers, patient demographics and injury characteristics are the main methods used for predicting sepsis in trauma patients. However, studies that verify their predictive value are limited, and the results are still controversial. More work should be conducted to explore more efficient and accurate ways to predict post-traumatic sepsis.

Serum soluble triggering receptor expressed on myeloid cells-1 and procalcitonin can reflect sepsis severity and predict prognosis: a prospective cohort study

Objective. To investigate the prognostic significance of serum soluble triggering receptor expressed on myeloid cells-1 (sTREM-1), procalcitonin (PCT), N-terminal probrain natriuretic peptide (NT-pro-BNP), C-reactive protein (CRP), cytokines, and clinical severity scores in patients with sepsis. Methods. A total of 102 patients with sepsis were divided into survival group (n = 60) and nonsurvival group (n = 42) based on 28-day mortality. Serum levels of biomarkers and cytokines were measured on days 1, 3, and 5 after admission to an ICU, meanwhile the acute physiology and chronic health evaluation II (APACHE II) and sequential organ failure assessment (SOFA) scores were calculated. Results. Serum sTREM-1, PCT, and IL-6 levels of patients in the nonsurvival group were significantly higher than those in the survival group on day 1 (P < 0.01). The area under a ROC curve for the prediction of 28 day mortality was 0.792 for PCT, 0.856 for sTREM-1, 0.953 for SOFA score, and 0.923 for APACHE II score. Multivariate logistic analysis showed that serum baseline sTREM-1 PCT levels and SOFA score were the independent predictors of 28-day mortality. Serum PCT, sTREM-1, and IL-6 levels showed a decrease trend over time in the survival group (P < 0.05). Serum NT-pro-BNP levels showed the predictive utility from days 3 and 5 (P < 0.05). Conclusion. In summary, elevated serum sTREM-1 and PCT levels provide superior prognostic accuracy to other biomarkers. Combination of serum sTREM-1 and PCT levels and SOFA score can offer the best powerful prognostic utility for sepsis mortality.

Procalcitonin as a marker of sepsis and outcome in patients with neurotrauma: an observation study

BACKGROUND

Procalcitonin (PCT) is a reliable biomarker of sepsis and infection. The level of PCT associated with sepsis and infection in patients with traumatic brain injury is currently unknown. The purpose of this study was to investigate the value of PCT and C-reactive protein (CRP) as diagnostic markers of sepsis and to evaluate the prognostic value of these markers related to the severity of injury, sepsis and mortality.

METHODS

105 adult patients with neurotrauma were enrolled in this study from June 2011 to February 2013. PCT and CRP were measured at admission and 2, 3, 5 and 7 days after admission. The sepsis criteria established by American College of Chest Physicians /Society of Critical Care Medicine Consensus Conference were used to identify patients. Injury Severity Score (ISS) and Glasgow Coma Score (GCS) were used to assess the severity of the injury. All these patients were monitored for 28 days.

RESULTS

At admission, the median level of PCT was consistent with the severity of brain injury as follows: mild 0.08 ng/ml (0.05 - 0.13), moderate 0.25 ng/ml (0.11 - 0.55) and severe 0.31 ng/ml (0.17 - 0.79), but the range of CRP levels varied greatly within the given severity of brain injury. Seventy-one (67.6%) patients developed sepsis. The initial levels of PCT at admission were statistically higher in patients with sepsis, compared with patients with systemic inflammatory response syndrome (SIRS), but there were no differences in the initial concentration of CRP between sepsis and SIRS. After adjusting for these parameters, multivariate logistic regression analysis revealed that PCT was an independent risk factor for septic complications (p < 0.05). The areas under the ROCs at admission for the prediction of mortality were 0.76 (p < 0.05) and 0.733 for PCT and CRP, respectively.

CONCLUSIONS

Increased levels of PCT during the course of the ICU stay could be an important indicator for the early diagnosis of sepsis after neurotrauma. In addition, high serum levels of PCT in patients with neurotrauma at admission indicate an increased risk of septic complications, and the daily measurement of PCT assists in guiding antibiotic therapy in neurotrauma patients.

Biomarkers predicting sepsis in polytrauma patients: Current evidence

INTRODUCTION

Major trauma still represents one of the leading causes of death in the first four decades of life. Septic complications represent the predominant causes of late death (45% of overall mortality) in polytrauma patients. The ability of clinicians to early differentiate between systemic inflammatory response syndrome (SIRS) and sepsis is demonstrated to improve clinical outcome and mortality. The identification of an "ideal" biomarker able to early recognize incoming septic complications in trauma patients is still a challenge for researchers.

AIM

To evaluate the existing evidence regarding the role of biomarkers to predict or facilitate early diagnosis of sepsis in trauma patients, trying to compile some recommendations for the clinical setting.

METHODS

An Internet-based search of the MEDLINE, EMBASE and Cochrane Library databases was performed using the search terms: "Biomarkers", "Sepsis" and "Trauma" in various combinations. The methodological quality of the included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies Checklist (QUADAS). After data extraction, the level of evidence available for each bio-marker was rated and presented using the "best-evidence synthesis" method, in line with the US Agency for Healthcare Research and Quality.

RESULTS

Thirty studies were eligible for the final analysis: 13 case-control studies and 17 cohort studies. The "strong evidence" available demonstrated the potential use of procalcitonin as an early indicator of post-traumatic septic complications and reported the inability of c-reactive protein (CRP) to specifically identify infective complications. Moderate, conflicting and limited evidence are available for the other 31 biomarkers.

CONCLUSION

Several biomarkers have been evaluated for predicting or making early diagnosis of sepsis in trauma patients. Current evidence does not support the use of a single biomarker in diagnosing sepsis. However, procalcitonin trend was found to be useful in early identification of post-traumatic septic course and its use is suggested (Recommendation Grade: B) in clinical practice.