Diagnostic Accuracy of Procalcitonin Compared to C-Reactive Protein and Interleukin 6 in Recognizing Gram-Negative Bloodstream Infection: A Meta-Analytic Study

Study of the Role of C-reactive Protein/Procalcitonin Ratio as a Prognostic Tool in ICU Patients with Sepsis: A Prospective Observational Study

Background

Prediction of prognosis in sepsis is an essential research area aiming to improve disease outcomes. In this study, we investigated the role of the C-reactive protein (CRP)/procalcitonin (PCT) ratio as a prognostic tool in sepsis patients.

Materials and methods

This prospective observational study was conducted at the intensive care unit (ICU) of Alexandria Main University Hospital in the period from January to June 2024. One hundred and seventy patients with a diagnosis of sepsis were enrolled. Sequential organ failure assessment (SOFA) score, acute physiology and chronic health evaluation (APACHEII) score and CRP/PCT ratio were calculated on admission (day 1), and as a follow-up on day 3. Patients were subsequently divided into survivor and non-survivor groups, and the data were compared.

Results

The CRP/PCT ratio was significantly lower, on admission and on follow-up, in non-survivor patients than in survivor patients. The ratio median (minimum-maximum) in non-survivors was 4.82 (1.51-23.28) vs 11.23 (1.85-136.7) in survivors on admission, and it was 7.37 (2.27-26.36) in non-survivors vs 11.37 (2.78-110.9) in survivors on day 3. The ratio was significantly lower in patients with septic shock than in non-septic shock patients. The ratio had a significant negative correlation with both SOFA and APACHEII scores. The receiver operating characteristic (ROC) curve showed high accuracy of the day 1 CRP/PCT ratio to predict mortality [area under curve (AUC = 0.835)], which is comparable to the day 1 SOFA score (AUC = 0.878) and higher than the day 1 PCT and day 1 APACHE scores.

Conclusion

Our results suggest a potential role for the CRP/PCT ratio, on admission and on follow-up, as a marker for predicting prognosis in sepsis patients, where low ratio values can predict poor disease outcome.

How to cite this article

Abdellatif EM, Hamouda EH. Study of the Role of C-reactive Protein/Procalcitonin Ratio as a Prognostic Tool in ICU Patients with Sepsis: A Prospective Observational Study. Indian J Crit Care Med 2024;28(12):1130-1138.

The epidemiological characteristics of invasive pulmonary aspergillosis and risk factors for treatment failure: a retrospective study

OBJECTIVE

The incidence of invasive pulmonary aspergillosis (IPA) is increasing gradually. This study analysed the epidemiological characteristics and prognostic factors of patients with IPA and explored the risk factors affecting prognosis.

MATERIALS AND METHODS

The clinical data and treatment of 92 patients with IPA were retrospectively analysed, and the patients were followed for 12 weeks. Patients were divided into an effective treatment group and an ineffective treatment group, and the risk factors affecting prognosis were discussed.

RESULTS

A total of 92 patients met the IPA inclusion criteria, and the most common genus of Aspergillus was Aspergillus fumigatus. The incidence of IPA was highest in patients with malignant tumours. IPA often coexisted with infections caused by other pathogens. We divided the patients into an effective treatment group and an ineffective treatment group according to prognosis. Compared with those in the effective treatment group, the procalcitonin (PCT) level, lactate dehydrogenase-to-albumin ratio (LDH/ALB) and neutrophil-to-lymphocyte ratio (NLR) in the ineffective treatment group were greater, the serum albumin level was lower, and the imaging findings revealed less nodules and bronchial wall thickening (P < 0.05). Among these factors, a decrease in the serum albumin concentration, an increase in the PCT level, coinfection and less bronchial wall thickening on imaging were independent risk factors for aspergillosis treatment failure.

CONCLUSION

A decreased albumin level, an elevated PCT level, coinfection, and less bronchial wall thickening were independent risk factors for treatment failure in patients with IPA. Attention should be given to the albumin level, coinfection status and imaging findings of patients.

Role of C-reactive Protein and Procalcitonin in Early Diagnostic Accuracy and Their Prognostic Significance in Sepsis

INTRODUCTION

Sepsis is a serious condition that often results in high fatality rates, particularly in intensive care units (ICUs). Its nonspecific clinical characteristics makes early diagnosis and therapy difficult, despite how critical they are. The use of biomarkers like procalcitonin (PCT) and C-reactive protein (CRP) in the diagnosis and prognosis of sepsis has demonstrated encouraging results. In contrast to PCT, which is highly selective for bacterial infections, CRP is an acute-phase protein that reflects systemic inflammation.

OBJECTIVE

This study aimed to assess the diagnostic accuracy and prognostic significance of CRP and PCT in early sepsis detection and outcome prediction.

METHODOLOGY

This study was a retrospective cohort study that involved 90 patients in the ICU who met the criteria for sepsis-3. CRP and PCT levels, clinical data, and outcomes were obtained from electronic medical records. The diagnostic accuracy was tested using receiver operating characteristic (ROC) curves, while the prognostic relevance was analyzed by Kaplan-Meier survival analysis and Cox proportional hazards regression.

RESULTS

The mean CRP level was 102.3 mg/L and PCT level was 5.4 ng/mL. ROC analysis revealed an area under the curve (AUC) of 0.78 for CRP and 0.82 for PCT, indicating better diagnostic performance for PCT. High levels of CRP and PCT were associated with poorer survival, with median survival times of 18 and 15 days, respectively, for high-level groups. Cox regression identified CRP and PCT as significant predictors of mortality, with hazard ratios of 1.50 and 1.68, respectively.

CONCLUSION

Both CRP and PCT are valuable biomarkers for diagnosing and prognosticating sepsis. PCT, with its higher specificity for bacterial infections, demonstrates superior diagnostic accuracy compared to CRP. Elevated levels of both biomarkers are associated with increased mortality risk, highlighting their potential role in early sepsis management and outcome prediction.

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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Diagnostic value of procalcitonin in infections in patients with malignant hematologic diseases

OBJECTIVES

The incidence of infections in patients with malignant hematologic diseases is extremely high and significantly affects their prognosis. Identifying early and precise biomarkers for infection is crucial for guiding the treatment of infections in these patients. Previous studies have shown that procalcitonin (PCT) can serve as an early diagnostic marker for bloodstream infections in patients with malignant hematologic diseases. This study aims to compare serum PCT levels in these patients with different pathogens, disease types, infection sites, and severity levels.

METHODS

Clinical data and laboratory results of infected patients with malignant hematologic diseases treated at the Department of Hematology, the Third Xiangya Hospital of Central South University from January 2018 to August 2023 were collected. General patient information was retrospectively analyzed. Serum PCT levels were compared among patients with different pathogens, types of malignant hematologic diseases, infection sites, and infection severity; Receiver operator characteristic (ROC) curves were used to determine the cut-off values and diagnostic value of serum PCT levels in diagnosing bloodstream infections versus local infections and severe infections versus non-severe infections. Mortality rates after 4-7 days of anti-infective treatment were compared among groups with rising, falling, and unchanged PCT levels.

RESULTS

A total of 526 patients with malignant hematologic diseases were included. The main pathogens were Gram-negative bacteria (272 cases, 51.7%), followed by Gram-positive bacteria (120 cases, 22.8%), fungi (65 cases, 12.4%), viruses (23 cases, 4.4%), and mixed pathogens (46 cases, 8.7%). The main types of malignant hematologic diseases were acute myeloid leukemia (216 cases, 41.1%), acute lymphoblastic leukemia (107 cases, 20.3%), and lymphoma (93 cases, 17.7%). Granulocyte deficiency was present in 68.3% (359 cases) of the patients during infection, with severe infection in 24.1% (127 cases). Significant differences in serum PCT levels were found among patients with different types of pathogens (P<0.001), with the highest levels in Gram-negative bacterial infections. Significant differences in serum PCT levels were also found among patients with different types of malignant hematologic diseases (P<0.05), with the highest levels in lymphoma patients. Serum PCT levels were significantly higher in systemic infections and severe infections compared to local infections and non-severe infections (both P<0.001). ROC curve analysis showed that the cut-off values for diagnosing bloodstream infections and severe infections were 0.22 and 0.28 ng/mL, with areas under the curve of 0.670 and 0.673, respectively. After 4-7 days of anti-infective treatment, the mortality rates of the PCT declining, PCT unchanged, and PCT rising groups were 11.9%, 21.2%, and 35.7%, respectively, and pairwise comparisons were statistically significant (all P<0.05).

CONCLUSIONS

PCT can be used as an auxiliary indicator for early identification of different pathogens, infection sites, and severity levels in patients with malignant hematologic diseases combined with infections. Dynamic monitoring of PCT levels after empirical antibiotic treatment provides important guidance for assessing patient's prognosis.

Diagnostic accuracy of interleukin-6 in multiple diseases: An umbrella review of meta-analyses

Objective

This review aims to conduct a comprehensive study of the diagnostic accuracy of interleukin-6 (IL-6) for multiple diseases by utilizing existing systematic reviews and meta-analyses.

Methods

We performed a thorough search of Embase, Web of Science, PubMed, and Cochrane Database of Systematic Reviews up to April 2023 to gather meta-analyses that investigate the diagnostic accuracy of IL-6. To assess the methodological quality of the studies, we employed the Assessing the Methodological Quality of Systematic Reviews-2 and Grading of Recommendations, Assessment, Development and Evaluation criteria.

Results

We included 34 meta-analyses out of the 3024 articles retrieved from the search. These meta-analyses covered 9 categories of diseases of the International Classification of Diseases-11. Studies rated as "Critically Low" or "Very Low" in the quality assessment process were excluded, resulting in a total of 6 meta-analyses that encompassed sepsis, colorectal cancer, tuberculous pleural effusion (TPE), endometriosis, among others. Among these diseases, IL-6 demonstrated a relatively high diagnostic potential in accurately identifying TPE and endometriosis.

Conclusions

IL-6 exhibited favorable diagnostic accuracy across multiple diseases, suggesting its potential as a reliable diagnostic biomarker in the near future. Substantial evidence supported its high diagnostic accuracy, particularly in the cases of TPE and endometriosis.

[Diagnostic accuracy of procalcitonin for bacteremia in the emergency department: a systematic review]

OBJECTIVE

Obtaining blood cultures (HC) is performed in 15% of the patients treated with suspicion of infection in the Hospital Emergency Services (ED) with a variable diagnostic yield (2-20%). The 30-day mortality of patients with bacteremia is two or three times higher than the rest with the same process. Procalcitonin (PCT) is a biomarker that has been used as a tool to help predict bacteremia in HEDs. The main objective of this systematic review is to investigate the diagnostic accuracy of PCT in predicting true bacteraemia in adult patients treated with clinical suspicion of infection in the ED, as well as to identify a specific PCT value as the most relevant from the clinical decision diagnostic point of view that can be recommended for decision making.

METHODS

A systematic review was performed following the PRISMA guidelines in the PubMed, Web of Science, EMBASE, Lilacs, Cochrane, Epistemonikos, Tripdatabase and ClinicalTrials.gov databases from January 2010 to May 31, 2023 without language restrictions and using a combination of MESH terms: "Bacteremia/ Bacteraemia/ Blood Stream Infection", "Procalcitonin", "Emergencies/ Emergency/ Emergency Department" and "Adults". Observational cohort studies and partially an systematic review were included. No meta-analysis techniques were performed, but the results were compared narratively.

RESULTS

A total of 1,372 articles were identified, of which 20 that met the inclusion criteria were finally analyzed. The included studies represent a total of 18,120 processed HC with 2,877 bacteraemias (15.88%). Ten studies were rated as high, 9 moderate and 1 low quality. The AUC-COR of all the studies ranges from 0.68 (95% CI: 0.59-0.77) to 0.98 (95% CI: 0.97-0.99). The PCT value >0.5 ng/ml is the most widely used and proposed in up to ten of the works included in this systematic review, whose estimated mean yield is an AUC-COR of 0.833. If only the results of the 6 high-quality studies using a cut-off point (PC) >0.5 ng/mL PCT are taken into account, the estimated mean AUC-COR result is 0.89 with Se of 77.6% and It is 78%.

CONCLUSIONS

PCT has a considerable diagnostic accuracy of bacteraemia in patients treated in EDs for different infectious processes. The CP>0.5 ng/ml has been positioned as the most suitable for predicting the existence of bacteraemia and can be used to reasonably rule it out.

Diagnostic value of serum CRP, PCT and IL-6 in children with nephrotic syndrome complicated by infection: a single center retrospective study

OBJECTIVE

The purpose was to look into the diagnostic value of serum CRP, PCT and IL-6 in children with nephrotic syndrome co-infection.

METHODS

One hundred and forty-nine children with nephrotic syndrome who met the inclusion and exclusion criteria were included in this study. The children were divided into three groups: bacterial infection group, non-bacterial infection group, and non-infection group. The diagnostic value was analyzed and compared using the ROC curve.

RESULTS

There was no statistically significant difference in the Leukocyte counts among three groups. The mean results of serum CRP, PCT and IL-6 were significantly higher in the bacterial infection group compared to those in the non-infection group (p < 0.05). AUC of CRP, PCT, IL-6 in bacterial infection were 0.791, 0.859, 0.783. The following combinations CRP + PCT + IL-6, IL-6 + PCT, CRP + PCT significantly increased the efficiency of bacterial infection diagnosis, the AUCs were 0.881, 0.884, and 0.884, respectively. AUC of PCT in non-bacterial infection was 0.663. The combinations of these three clinical indicators performed no better than PCT in ROC analysis.

CONCLUSION

Normal CRP or IL-6 levels do not rule out the diagnosis of bacterial infection in children on long-term glucocorticoid therapy. The appropriate combination of two or three indicators can improve the diagnostic value.

IMPACT

This study evaluated the diagnostic value of the serum concentrations of CRP, PCT and IL-6 and assessed whether the value of their combined application is better than when used alone for diagnosing primary nephrotic syndrome complicated by infection. The elevation in leukocyte count cannot be used to diagnose children with nephrotic syndromes on long-term glucocorticoid treatment who have bacterial infections. Normal CRP or IL-6 levels do not rule out the diagnosis of bacterial infection in children on long-term glucocorticoid therapy. The appropriate combination of two or three indicators can improve diagnostic value, sensitivity, and specificity.

Biomarkers in sepsis-looking for the Holy Grail or chasing a mirage!

Sepsis is defined as a life-threatening organ dysfunction caused by the dysregulated host response to infection. It is a complex syndrome and is characterized by physiologic, pathologic and biochemical abnormalities in response to an infection. Diagnosis of sepsis is based on history, physical examination and other investigations (including biomarkers) which may help to increase the certainty of diagnosis. Biomarkers have been evaluated in the past for many diseases and have been evaluated for sepsis as well. Biomarkers may find a possible role in diagnosis, prognostication, therapeutic monitoring and anti-microbial stewardship in sepsis. Since the pathophysiology of sepsis is quite complex and is incompletely understood, a single biomarker that may be robust enough to provide all information has not been found as of yet. However, many biomarkers have been studied and some of them have applications at the bedside and guide clinical decision-making. We evaluated the PubMed database to search for sepsis biomarkers for diagnosis, prognosis and possible role in antibiotic escalation and de-escalation. Clinical trials, meta-analyses, systematic reviews and randomized controlled trials were included. Commonly studied biomarkers such as procalcitonin, Soluble urokinase-type plasminogen activator (Supar), presepsin, soluble triggering receptor expressed on myeloid cells 1, interleukin 6, C-reactive protein, etc., have been described for their possible applications as biomarkers in septic patients. The sepsis biomarkers are still an area of active research with newer evidence adding to the knowledge base continuously. For patients presenting with sepsis, early diagnosis and prompt resuscitation and early administration of anti-microbials (preferably within 1 h) and source control are desired goals. Biomarkers may help us in the diagnosis, prognosis and therapeutic monitoring of septic patients. The marker redefining our view on sepsis is yet a mirage that clinicians and researchers continue to chase.

Evaluation of the relationship between procalcitonin level and the causative pathogen in intensive care patients with sepsis

Aim: This study was designed to investigate how procalcitonin (PCT) levels are affected by different pathogens in patients with sepsis. Materials & methods: A total of 110 Gram-positive sepsis, 62 Gram-negative sepsis and 27 fungal sepsis patients were included in the study. Kaplan-Meier and ROC curve analysis was performed to assess PCT levels. Results: PCT levels were 2.36 ng/ml in Gram-negative patients, 0.79 ng/ml in Gram-positive patients and 0.89 ng/ml in fungal patients. The area under the curve for PCT was 0.608, the cutoff value was 1.34, sensitivity was 56.50% the specificity was 56.50%. Conclusion: PCT survival levels of 7.71 ng/ml in Gram-negative patients, 2.65 ng/ml in Gram-positive patients and 1.16 ng/ml in fungal patients can be evaluated to predict survival.

The ability of inflammatory markers to recognize infection in cancer patients with fever at admission

Infection is one of the main causes of death in cancer patients. Accurate identification of fever caused by infection could avoid unnecessary antibiotic treatment and hospitalization. This study evaluated the diagnostic value of procalcitonin (PCT), C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-10 (IL-10), and other commonly used inflammatory markers in suspected infected adult cancer patients with fever, for better use of antibiotics. This research retrospective analyzed the clinical data of 102 adult cancer patients with fever and compared the serum levels of commonly used inflammatory markers for different fever reasons. Receiver-operating characteristic (ROC) curve and logistic regression analyses were performed. In adult cancer patients with fever, the serum PCT, CRP, IL-6, and IL-10 levels of infected patients were significantly higher than uninfected patients (median 1.19 ng/ml vs 0.14 ng/ml, 93.11 mg/l vs 56.55 mg/l, 123.74 pg/ml vs 47.35 pg/ml, 8.74 pg/ml vs 3.22 pg/ml; Mann-Whitney p = 0.000, p = 0.009, p = 0.004, p = 0.000, respectively). The ROC area under the curve(AUC) was 0.769 (95% confidence interval (CI) 0.681-0.857; p = 0.000) for PCT, 0.664 (95% CI 0.554-0.775; p = 0.009) for CRP, 0.681(95% CI 0.576-0.785; p = 0.004) for IL-6, and 0.731(95% CI 0.627-0.834; p = 0.000) for IL-10. PCT had specificity of 96.67% and positive predictive value (PPV) of 97.6%, when the cut-off value is set as 0.69 ng/ml. The serum IL-6 and IL-10 levels also had significant differences between the infected and uninfected cancer patients with advanced disease (median 128.92 pg/ml vs 36.40 pg/ml, 8.05 pg/ml vs 2.92 pg/ml; Mann-Whitney p = 0.003, p = 0.001, respectively). For the patients with neutropenia, IL-6 and IL-10 had higher AUC of 0.811 and 0.928, respectively. With a cut-off of 9.10 pg/ml, IL-10 had the highest sensitivity 83.33% and specificity 100%. In adult cancer patients, PCT had the best performance compared to CRP, IL-6, and IL-10 in differentiating infected from uninfected causes of fever, with high specificity and PPV. IL-6 and IL-10 might be useful in cancer patients with severe bloodstream infections and advanced disease. However, for patients with neutropenia, IL-10 might be more valuable than PCT in diagnosing infection.

Endogenous Carboxyhemoglobin Level Variation in COVID-19 and Bacterial Sepsis: A Novel Approach?

Background: The increased production of carbon monoxide (CO) in sepsis has been proven, but the blood level variations of carboxyhemoglobin (COHb) as a potential evolutionary parameter of COVID-19 and sepsis/septic shock have yet to be determined. This study aims to evaluate the serum level variation of COHb as a potential evolutionary parameter in COVID-19 critically ill patients and in bacterial sepsis. Materials and method: A prospective and observational study was conducted on two groups of patients: the bacterial sepsis group (n = 52) and the COVID-19 group (n = 52). We followed paraclinical parameters on Day 1 (D1) and Day 5 (D5) of sepsis/ICU admission for COVID-19 patients. Results: D1 of sepsis: statistically significant positive correlations between: COHb values and serum lactate (p = 0.024, r = 0.316), and total bilirubin (p = 0.01, r = 0.359). In D5 of sepsis: a statistically significant positive correlations between: COHb values and procalcitonin (PCT) (p = 0.038, r = 0.402), and total bilirubin (p = 0.023, r = 0.319). D1 of COVID-19 group: COHb levels were statistically significantly positively correlated with C-reactive protein CRP values (p = 0.003, r = 0.407) and with PCT values (p = 0.022, r = 0.324) and statistically significantly negatively correlated with serum lactate values (p = 0.038, r = −0.285). Conclusion: COHb variation could provide rapid information about the outcome of bacterial sepsis/septic shock, having the advantages of a favorable cost-effectiveness ratio, and availability as a point-of-care test.

Infection Biomarkers Based on Metabolomics

Current infection biomarkers are highly limited since they have low capability to predict infection in the presence of confounding processes such as in non-infectious inflammatory processes, low capability to predict disease outcomes and have limited applications to guide and evaluate therapeutic regimes. Therefore, it is critical to discover and develop new and effective clinical infection biomarkers, especially applicable in patients at risk of developing severe illness and critically ill patients. Ideal biomarkers would effectively help physicians with better patient management, leading to a decrease of severe outcomes, personalize therapies, minimize antibiotics overuse and hospitalization time, and significantly improve patient survival. Metabolomics, by providing a direct insight into the functional metabolic outcome of an organism, presents a highly appealing strategy to discover these biomarkers. The present work reviews the desired main characteristics of infection biomarkers, the main metabolomics strategies to discover these biomarkers and the next steps for developing the area towards effective clinical biomarkers.

Prognostic Value of Procalcitonin, C-Reactive Protein, and Lactate Levels in Emergency Evaluation of Cancer Patients with Suspected Infection

Simple Summary

Cancer patients are at increased risk of infections and related complications, including sepsis. We developed a scoring system for mortality prediction based on readily available clinical and laboratory data, including the quick sequential organ failure assessment (qSOFA) score, cancer subtype, and several laboratory markers (procalcitonin, C-reactive protein, lactate dehydrogenase, and albumin) that can be used in emergency departments for cancer patients with suspected infection. The prediction score, which stratifies patients into four different risk groups (from low risk to very high risk), achieved excellent performance in predicting 14-day mortality, with an area under the receiver operating characteristic curve value of 0.88 (95% confidence interval 0.85–0.91). The score was also effective in predicting intensive care unit admission and 30-day mortality.

Abstract

Cancer patients have increased risk of infections, and often present to emergency departments with infection-related problems where physicians must make decisions based on a snapshot of the patient’s condition. Although C-reactive protein, procalcitonin, and lactate are popular biomarkers of sepsis, their use in guiding emergency care of cancer patients with infections is unclear. Using these biomarkers, we created a prediction model for short-term mortality in cancer patients with suspected infection. We retrospectively analyzed all consecutive patients who visited the emergency department of MD Anderson Cancer Center between 1 April 2018 and 30 April 2019. A clinical decision model was developed using multiple logistic regression for various clinical and laboratory biomarkers; coefficients were used to generate a prediction score stratifying patients into four groups according to their 14-day mortality risk. The prediction score had an area under the receiver operating characteristic curve value of 0.88 (95% confidence interval 0.85–0.91) in predicting 14-day mortality. The prediction score also accurately predicted intensive care unit admission and 30-day mortality. Our simple new scoring system for mortality prediction, based on readily available clinical and laboratory data, including procalcitonin, C-reactive protein, and lactate, can be used in emergency departments for cancer patients with suspected infection.

Combined procalcitonin and hemogram parameters contribute to early differential diagnosis of Gram-negative/Gram-positive bloodstream infections

Background

Hemogram parameters and procalcitonin (PCT) play auxiliary roles in the diagnosis and outcome of sepsis. However, it is not clear whether these indicators can quickly distinguish bacterial classification or guide the choice of empirical antibiotics.

Methods

We retrospectively enrolled 381 patients with bloodstream infections (BSI), divided into Gram‐positive bloodstream infections (GP‐BSI) and Gram‐negative bloodstream infections (GN‐BSI). Demographic parameters, hemogram parameters, and PCT were recorded and compared between the two groups.

Results

The mean platelet volume (MPV), platelet distribution width (PDW), and PCT in the GN‐BSI group were significantly higher than those in the GP‐BSI group, while the platelet count (PLT), plateletcrit, platelet count‐to‐white blood cell count ratio (PWR), platelet count‐to‐neutrophil count ratio (PNR), platelet count‐to‐PCT ratio (PLT/PCT), and mean platelet volume‐to‐PCT ratio (MPV/PCT) were significantly lower in the GN‐BSI group. Multivariate stepwise logistic regression analysis revealed that the independent predictors of GN‐BSI were MPV, PWR, and PCT. The areas under the curve (AUC) for this prediction model was 0.79, with sensitivity =0.75 and specificity =0.71.

Conclusions

There were significant differences in terms of PCT, platelet parameters, and platelet‐related index‐PCT ratio between GN‐BSI and GP‐BSI. Combined PCT and hemogram parameters are more conducive to the early differential diagnosis of bacterial classification of BSI.

Lactate and procalcitonin levels in peripartum women with intraamniotic infection

BACKGROUND

Pregnant women are vulnerable to infection as their immune response is modulated.

OBJECTIVE

Serum biomarkers are used to diagnose and manage severe infections, but data on their utility during labor are limited. We compared lactate and procalcitonin levels in women with and without an intraamniotic infection to determine whether they are useful biomarkers for infection during labor.

STUDY DESIGN

We performed a prospective, observational cohort study of term, singleton pregnancies admitted with planned vaginal delivery in 2019 at a university medical center. The lactate and procalcitonin levels were determined during early labor, within 2 hours following delivery, and on postpartum day 1. Women with an intraamniotic infection in addition had their lactate and procalcitonin levels determined following an intraamniotic infection diagnosis. Samples were processed immediately in the hospital clinical laboratory. The primary outcome was the mean lactate level following delivery. The secondary outcomes were the lactate and procalcitonin levels at other time points. Comparisons based on infection status were performed using multivariate linear regressions.

RESULTS

A total of 22 women with intraamniotic infection and 29 uninfected women were included. The mean early labor lactate level (1.47 vs 1.49 mmol/L) and mean procalcitonin level (0.048 vs 0.039 ng/mL) did not differ and were normal in the uninfected and intraamniotic infection groups. The mean lactate level was highest following delivery for women in both the uninfected and intraamniotic infection groups (2.00 vs 2.33 mmol/L; adjusted P=.08; 95% confidence interval, 0.98-1.53). The lactate level returned to normal by postpartum day 1 and did not differ significantly based on the infection status at any time point in the adjusted models. The procalcitonin level following delivery was higher among women with vs without an intraamniotic infection (0.142 vs 0.091 ng/mL; adjusted P=.03). The procalcitonin level rose further in both the intraamniotic infection and uninfected groups on postpartum day 1 (0.737 vs 0.408 ng/mL; adjusted P=.05).

CONCLUSION

The lactate level is not significantly elevated in pregnant women with an intraamniotic infection above the physiological increase that is observed in women without infection at delivery. The procalcitonin level is elevated at delivery in women with an intraamniotic infection and warrants further investigation as a peripartum infection marker.

Analysis of Risk Factors and Clinical Indicators in Bloodstream Infections Among Patients with Hematological Malignancy

Purpose

The incidence of bloodstream infection (BSI) is more common in patients with hematological malignancy. It is important to distinguish infectious episodes from noninfectious episodes. The present study was aimed to describe the epidemiology, clinical indexes, and antibiotic use for in-hospital bloodstream infections of hematological malignancy patients.

Patients and Methods

Single-center retrospective research was performed on hematological malignancy patients admitted to our hospital from July 2015 to March 2018. Laboratory and clinical information from 322 febrile patients were acquired. These episodes were divided by blood culture results into two groups: 1) blood culture positive-group, 2) blood culture negative-group.

Results

In the 322 febrile cases, 81 (25.2%) patients were blood culture positive, and among them, Gram-negative (G-) bacteria (51.9%) were more isolated than Gram-positive (G+) bacteria (32.1%) and fungi (7.4%). Gram-negative bacteria were more likely to have drug resistance than G+ bacteria. Independent risk factors revealed that patients with complications, high levels of procalcitonin (PCT), glucose, interleukin-6 (IL-6), and d-dimer (D-D), and low concentration of albumin were correlated with the occurrence of BSI. PCT, IL-6 and D-D performed well in differentiating the positive group from the negative group. Moreover, IL-6 and D-D showed excellent performance in differentiating G- and G+ groups, with the areas under the curve all above 0.8.

Conclusion

We analyzed the risk factors for BSI in patients with hematological malignancy, the distribution of bacteria, antibiotic resistance, and the changes in clinical parameters. This single-center retrospective study may provide clinicians insight into the diagnosis and treatment of BSI.

ITIH4, as an inflammation biomarker, mainly increases in bacterial bloodstream infection

Bloodstream infection (BSI) is usually accompanied with the changes of varieties of inflammation proteins. In our previous study, we identified that inter-α-trypsin inhibitor heavy chain H4 (ITIH4) was highly expressed in the infection arms than the normal control arm. However, the correlated verification and mechanism remain obscure. Escherichia coli infected mice model and clinical serum samples were used to validate the concentration of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10), as well as ITIH4, in ELISA method. Cytokines (IL-6, TNF-α, IL-10 and lipopolysaccharide (LPS)) were used to stimulate the HepG2 cell model to explore which cytokines influence the expression of ITIH4. JAK/STAT inhibitor was treated before IL-6 and LPS stimulation. Westernblot, as well as real-time PCR were performed to detect the expression of ITIH4 in liver tissue from protein and transcription levels. Immunohistochemistry analysis was used to observe the expression of ITIH4 in mice liver tissue. In mice model, IL-6, TNF-α, as well as IL-10 increased in the infection arms than the normal control arm. ITIH4 in serum and liver tissue of mice model increased from 1 h to 128 h, which were remarkably different from that of the normal control arm. Besides, ITIH4 increased in the bacterial infection arm greatly than the fungemia arm, mycoplasma pneumoniae (MP) arm and febrile arm in clinical serum samples. Furthermore, using the HepG2 cell line, we demonstrated that ITIH4 was up-regulated at both protein and mRNA levels upon dose- and time- response treatments with IL-6, as well as LPS. Moreover, IL-6 or LPS mediated induction of ITIH4 expression could be significantly decreased by treatment with an JAK/STAT inhibitor in protein or mRNA level. No changes were observed after TNF-α or IL-10 stimulation. ITIH4 might be a critical inflammatory biomarker which correlated with the development of BSI, especially with bacterial bloodstream infection. It is expected that this study would provide some insights into potential functional mechanisms underlying BSI.

MicroRNA Biomarkers for Infectious Diseases: From Basic Research to Biosensing

In the pursuit of improved diagnostic tests for infectious diseases, several classes of molecules have been scrutinized as prospective biomarkers. Small (18–22 nucleotide), non-coding RNA transcripts called microRNAs (miRNAs) have emerged as promising candidates with extensive diagnostic potential, due to their role in numerous diseases, previously established methods for quantitation and their stability within biofluids. Despite efforts to identify, characterize and apply miRNA signatures as diagnostic markers in a range of non-infectious diseases, their application in infectious disease has advanced relatively slowly. Here, we outline the benefits that miRNA biomarkers offer to the diagnosis, management, and treatment of infectious diseases. Investigation of these novel biomarkers could advance the use of personalized medicine in infectious disease treatment, which raises important considerations for validating their use as diagnostic or prognostic markers. Finally, we discuss new and emerging miRNA detection platforms, with a focus on rapid, point-of-care testing, to evaluate the benefits and obstacles of miRNA biomarkers for infectious disease.