Procalcitonin as an early marker of bacterial infection in neutropenic febrile children with acute lymphoblastic leukemia

Diagnostic and Monitoring Value of β-2 Transferrin and Transferrin for Intracranial Infection After Neurosurgery

BACKGROUND AND OBJECTIVES

After neurosurgery, intracranial infection is a common complication with high rates of clinical impairment and death. Traditional diagnostic approaches are time-consuming. Early and correct diagnosis improves infection control, treatment success, and survival. Novel markers are used to diagnose and classify post-neurosurgical meningitis (PNM) to overcome the difficulties of diagnosing postoperative intracranial infections and avoid the drawbacks of existing diagnostic measures. The objective was to investigate the diagnostic value of β-2 transferrin (β-2TF) and transferrin (TF) in the cerebrospinal fluid (CSF) for the identification of intracranial infection after neurosurgery.

METHODS

Owing to their symptoms and laboratory results, 168 patients with suspected intracranial infection after neurosurgery were divided into 3 groups: post-neurosurgical bacterial meningitis (PNBM; n = 61), post-neurosurgical aseptic meningitis (PNAM; n = 45), and non-PNM (n = 62). We measured lactate (LA), β-2TF, and TF levels in the CSF.

RESULTS

CSF LA levels were significantly higher in the PNM, PNBM, and PNAM groups compared with the non-PNM group ( P < .05). The CSF β-2TF level in PNM, PNBM, and PNAM were statistically higher than those in non-PNMs ( P < .05). CSF TF levels in the PNBM group were statistically higher than those in the PNAM and non-PNM groups ( P < .05). The PNBM and non-PNM receiver operating curve (ROC) analysis indicates that the cutoff values for the combination (LA, β-2TF, TF) was 0.349, and the area under the curve (AUC) was 0.945 ( P < .0001), with 92.86% sensitivity and 92.98% specificity. The PNAM and non-PNM ROC analysis indicates that the cutoff values for the combination (LA, β-2TF, TF) was 0.346, and the AUC was 0.962 ( P < .0001), with 89.29% sensitivity and 90.24% specificity. The PNM and non-PNM ROC analysis indicates that the cutoff values for the combination (LA, β-2TF, TF) was 0.609, and the AUC was 0.941 ( P < .0001), with 96.36% sensitivity and 82.83% specificity. A Glasgow Coma Scale score ≤8, LA, β-2TF/TF ratio, length of hospital stay, intensive care unit admission, poor surgical wound, and craniotomy were associated with poor outcomes ( P < .05). LA and β-2TF were independent risk factors for intracranial infection.

CONCLUSION

Postoperative cerebral infections can be identified using CSF β-2TF as a particular marker protein. CSF TF helps distinguish PNBM from PNAM. Combining CSF LA with them improves diagnostic speed, sensitivity, and accuracy. LA and β-2TF were independent risk factors for cerebral infection.

Hussain, Rajwa H. Essa. Molecular study of Enterobacter cloacae isolated from leukemia patients

Introduction and Aim: Polymerase chain reaction (PCR) of 16S rRNA and virulence genes associated with Type Three Secretion System (TTSS) has been used as a rapid method for the identification of the pathogen Enterobacter cloacae in leukemia patients. Rapid diagnosis of this pathogen becomes necessary for starting a proper treatment in these patients. In the current study, we aimed to isolate Enterobacter cloacae from leukemia patients and study the TSSS genes associated with these isolates using molecular methods.   Materials and Methods: E. cloacae isolates identified using biochemical tests was molecular confirmed by                 16S rRNA polymerase chain reaction (PCR).  Genomic DNA extracted was also subjected to the Type Three Secretion System (TTSS) associated virulence genes escV and ascV using specific primers.   Results: 30 (23.07%) out of the 130 blood samples tested in this study were identified as E. cloaca by biochemical tests. Further confirmation using molecular methods showed only 11 of these isolates to be 16S rRNA positive. Few of these isolates were positive for the TTSS associated ASCV gene of the samples positive for presence of the ascV gene. All strains were negative for the escV gene.   Conclusion: PCR is the best technique in comparison with other conventional methods for the diagnosis of                       E. cloacae in leukemia patients because of its safety, high sensitivity, specificity, and speed.

Biomarkers for Diagnosing Febrile Illness in Immunocompromised Children: A Systematic Review of the Literature

OBJECTIVE

This study aims to assess the performance of biomarkers used for the prediction of bacterial, viral, and fungal infection in immunocompromised children upon presentation with fever.

METHODS

We performed a literature search using PubMed and MEDLINE and In-Process & Other Non-indexed Citations databases. Cohort and case-control studies assessing biomarkers for the prediction of bacterial, viral, or fungal infection in immunocompromised children vs. conventional microbiological investigations were eligible. Studies including adult patients were eligible if pediatric data were separately assessable. Data on definitions used for infections, fever, and neutropenia and predictive values were collected. Risk of bias was assessed with the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

RESULTS

Fifty-two studies involving 13,939 febrile episodes in 7,059 children were included. In total, 92.2% were in cancer patients (n = 48), and 15.7% also included hematopoietic stem cell transplantation patients (n = 8). Forty-three biomarkers were investigated, of which 6 (CRP, PCT, IL-8, IL-6, IL-10, and TNFα) were significantly associated with bacterial infection at admission, studied in multiple studies, and provided predictive data. Literature on the prediction of viral and fungal infection was too limited. Eight studies compared C-reactive protein (CRP) and procalcitonin (PCT), with PCT demonstrating superiority in 5. IL-6, IL-8, and IL-10 were compared with CRP in six, four, and one study, respectively, with mixed results on diagnostic superiority. No clear superior biomarker comparing PCT vs. IL-6, IL-8, or IL-10 was identified.

DISCUSSION

There is great heterogeneity in the biomarkers studied and cutoff values and definitions used, thus complicating the analysis. Literature for immunocompromised children with non-malignant disease and for non-bacterial infection is sparse. Literature on novel diagnostics was not available. We illustrated the challenges of diagnosing fever adequately in this study population and the need for improved biomarkers and clinical decision-making tools.

Presepsin and Midregional Proadrenomedullin in Pediatric Oncologic Patients with Febrile Neutropenia

OBJECTIVE

In this study, we investigated the roles of presepsin (PSP) and midregional proadrenomedullin (mr-proADM) in children with febrile neutropenia (FN) due to chemotherapy.

METHODS

We assessed 36 FN episodes in 26 children. Patients were classified into bacteremia (B) and fever of unknown origin (FUO) groups. We evaluated PSP and mr-proADM at admission (T0), after 24/48 h (T1), and after 5 days (T2).

RESULTS

PSP and mr-proADM levels were elevated at T0 and significantly decreased at T2. mr-proADM levels did not significantly differ between the B and FUO groups. PSP levels significantly differed between the B and FUO groups only at T1. Both PSP and mr-proADM levels at T0 were a predictor of length of hospital stay but not of the duration of fever. Finally, receiver operating characteristic curve analysis showed that PSP and mr-proADM had low diagnostic accuracy for blood culture positivity.

CONCLUSION

PSP and mr-proADM display poor clinical usefulness for FN in oncologic children.

Neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio in evaluation of inflammation in non-dialysis patients with end-stage renal disease (ESRD)

Background

Neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) have been reported to be associated with inflammation in end-stage renal disease (ESRD) receiving dialysis. However, the value of NLR and PLR in non-dialysis patients with ESRD remains unclear.

Methods

Among 611 non-dialysis patients with ESRD in The First Affiliated Hospital of University of South China (2012–2018), we compared NLR and PLR in patients with high-sensitivity C-reactive protein (hs-CRP) levels of ≤3 mg/L vs. > 3 mg/L. Correlation of NLR and PLR to hs-CRP, PCT, ferritin were analyzed. Receiver operating characteristics (ROC) analysis was used for estimating sensitivity and specificity of NLR and PLR.

Results

NLR was higher in the patients with high hs-CRP levels (> 3 mg/L), compared to patients with low hs-CRP levels (≤ 3 mg/L) [5.74 (3.54–9.01) vs. 3.96 (2.86–5.85), p < 0.0001]. Additionally, PLR was higher in high hs-CRP group than in low group [175.28 (116.67–252.26) vs. 140.65 (110.51–235.17), p = 0.022]. In the current study, NLR and PLR were both positively correlated with hs-CRP (rs = 0.377, p = 0.000 for NLR; rs = 0.161, p = 0.001 for PLR), PCT, leukocytes, neutrophils, platelets, and age. NLR or PLR with a cut-off value of 5.07 or 163.80 indicated sensitivity and specificity were 65.67 and 66.37% (AUC = 0.69) or 57.21 and 57.52% (AUC = 0.55), respectively.

Conclusions

NLR or PLR was positively correlated with hs-CRP in non-dialysis patients with ESRD. NLR might be better for identifying inflammation than PLR in this population.

Pro-inflammatory cytokine ratios determine the clinical course of febrile neutropenia in children receiving chemotherapy

Background

Febrile neutropenia is a common and serious complication during treatment of childhood cancer. Empirical broad-spectrum antibiotics are usually administered until neutrophil cell count recovery. It was the aim of this study to investigate cytokine profiles as potential biomarkers using in-vitro sepsis models to differentiate between distinct clinical courses of febrile neutropenia (FN).

Methods

We conducted an observational study in FN episodes of pediatric oncology patients. Courses of neutropenia were defined as severe in case of proven blood stream infection or clinical evidence of complicated infection. We collected blood samples at various time points from the onset of FN and stimulated ex vivo with lipopolysaccharide (LPS) and Staphylococcus epidermidis (SE) for 24 h. Twenty-seven cytokine levels were measured in the whole blood culture supernatants by a multiplex immunoassay system.

Results

Forty-seven FN episodes from 33 children were investigated. IL-8, IL-1β, and MCP-1 expression increased significantly over time. IL-8, MIP-1α, MIP-1β, MCP-1, and TNF-α showed significantly lower concentration in patients with a clinically severe course of the FN.

Conclusions

Distinct patterns of cytokine profiles seem to be able to determine infectious FN and to predict the severity of its clinical course. If these data can be verified in a multi-centre setting, this may finally lead to an individualized treatment strategy facilitating antibiotic stewardship in these patients.

Predictive value of PCT and IL-6 for bacterial infection in children with cancer and febrile neutropenia

Purpose

Only a third of children with cancer and febrile neutropenia (FN) have a proven bacterial infection; nevertheless, most children are hospitalized and treated with intravenous antibiotics. Several biomarkers have been proposed as predictive markers for bacterial infection in this population. We aimed to evaluate the role of interleukin-6 (IL-6) and procalcitonin (PCT) in diagnosing bacterial infection in children with cancer and FN.

Methods

The study population was derived from a prospective database (2006–2013, IL-8 study) comprising children with cancer who presented with FN. From stored plasma samples (taken at admission and/or at 12–24 h), we determined the PCT and IL-6 levels. Consequently, we explored their relation with the presence of bacterial infection (positive blood culture, radiologically documented infection or clinical bacterial focus). We predefined cutoff values at 60 ng/L for IL-6 and 0.25 ng/mL for PCT.

Results

Seventy-seven FN episodes in 55 children with cancer were included. In 18 episodes (23.4%), a bacterial infection was documented. Both at presentation and after 12–24 h, median values of IL-6 and PCT were significantly higher in patients with a bacterial infection compared to patients without a bacterial infection. With both biomarkers above cutoff values, sensitivity was 93% (with either one, this was even 100%). The identified group at low risk for bacterial infection comprised 41% of the population.

Conclusion

PCT and IL-6 are promising markers in identifying bacterial infection in children with cancer and FN. In a subsequent project, we will incorporate these biomarkers in a risk assessment model that we will test prospectively in a clinical trial.

Diagnosis and empirical treatment of fever of unknown origin (FUO) in adult neutropenic patients: guidelines of the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO)

Fever may be the only clinical symptom at the onset of infection in neutropenic cancer patients undergoing myelosuppressive chemotherapy. A prompt and evidence-based diagnostic and therapeutic approach is mandatory. A systematic search of current literature was conducted, including only full papers and excluding allogeneic hematopoietic stem cell transplant recipients. Recommendations for diagnosis and therapy were developed by an expert panel and approved after plenary discussion by the AGIHO. Randomized clinical trials were mainly available for therapeutic decisions, and new diagnostic procedures have been introduced into clinical practice in the past decade. Stratification into a high-risk versus low-risk patient population is recommended. In high-risk patients, initial empirical antimicrobial therapy should be active against pathogens most commonly involved in microbiologically documented and most threatening infections, including Pseudomonas aeruginosa, but excluding coagulase-negative staphylococci. In patients whose expected duration of neutropenia is more than 7 days and who do not respond to first-line antibacterial treatment, specifically in the absence of mold-active antifungal prophylaxis, further therapy should be directed also against fungi, in particular Aspergillus species. With regard to antimicrobial stewardship, treatment duration after defervescence in persistently neutropenic patients must be critically reconsidered and the choice of anti-infective agents adjusted to local epidemiology. This guideline updates recommendations for diagnosis and empirical therapy of fever of unknown origin in adult neutropenic cancer patients in light of the challenges of antimicrobial stewardship.

Procalcitonin to Detect Bacterial Infections in Critically Ill Pediatric Patients

The diagnostic power of procalcitonin (PCT) in the pediatric intensive care unit (PICU) is uncertain. This study aimed to determine the diagnostic ability of PCT to detect serious bacterial infections (SBI) in a heterogeneous PICU population. This was a retrospective cohort study of patients on whom a PCT level was obtained within 48 hours of admission to a PICU from 2013 to 2015. Discriminatory ability of PCT to predict SBI was examined by test and receiver operating characteristics (AUC [area under the curve]-ROC). Seventy-five patients were included and 28 (37%) had an SBI (median PCT = 6.48 ng/mL) compared with 47 (63%) in the noninfection group (median PCT = 0.23 ng/mL, P < .0001). PCT was able to adequately predict SBI (AUC-ROC = 0.83, 95% CI 0.74-0.93; P < .0001), and a PCT ≥1.28 ng/mL was the optimal threshold to detect SBI with a positive predictive value of 76.7% and negative predictive value of 88.9%. PCT adequately predicted SBI in a heterogeneous PICU population and may be useful for minimizing antibiotic consumption.

Use of biomarkers in pediatric sepsis: literature review

Despite advances in recent years, sepsis is still a leading cause of hospitalization and mortality in infants and children. The presence of biomarkers during the response to an infectious insult makes it possible to use such biomarkers in screening, diagnosis, prognosis (risk stratification), monitoring of therapeutic response, and rational use of antibiotics (for example, the determination of adequate treatment length). Studies of biomarkers in sepsis in children are still relatively scarce. This review addresses the use of biomarkers in sepsis in pediatric patients with emphasis on C-reactive protein, procalcitonin, interleukins 6, 8, and 18, human neutrophil gelatinase, and proadrenomedullin. Assessment of these biomarkers may be useful in the management of pediatric sepsis.

Current use and potential role of procalcitonin in the diagnostic work up and follow up of febrile neutropenia in hematological patients

INTRODUCTION

Febrile neutropenia (FN) represents a life-threatening complication in hematological malignancies. Its etiology is most often due to infections even though FN of other origins, such as tumor-related fever and non-infectious inflammation, should rapidly be ruled out. Initially, C-reactive protein and, more recently, procalcitonin (PCT) have been proposed as useful biomarkers for differential diagnosis. PCT was shown to be a good biomarker of bacterial infections and their clinical outcomes. Definition of standard cut-offs and design of PCT-guided treatment protocols remain however to be defined. Areas covered: In this review, highlights on the current clinical use of PCT and its potential role as a diagnostic tool have been discussed by a panel of physicians from different areas of expertise. We provide current clinical evidence that PCT has been shown to be a reliable biomarker to differentiate fever of bacterial origin from other causes. Moreover, the Authors convened to a round-table to discuss their 'real-life experience' and offer their recommendations by a Delphi survey. Expert commentary: PCT has an important clinical role in FN. Issues such as the validation of a specific decision algorithm that includes PCT to monitor antibiotic choice and treatment duration will be addressed in prospective studies.

Clinical usefulness of serum procalcitonin level in distinguishing between Kawasaki disease and other infections in febrile children

Purpose

The aims of this study were to compare serum procalcitonin (PCT) levels between febrile children with Kawasaki disease (KD) and those with bacterial or viral infections, and assess the clinical usefulness of PCT level in predicting KD.

Methods

Serum PCT levels were examined in febrile pediatric patients admitted between August 2013 and August 2014. The patients were divided into 3 groups as follows: 49 with KD, 111 with viral infections, and 24 with bacterial infections.

Results

The mean PCT level in the KD group was significantly lower than that in the bacterial infection group (0.82±1.73 ng/mL vs. 3.11±6.10 ng/mL, P=0.002) and insignificantly different from that in the viral infection group (0.23±0.34 ng/mL,P=0.457). The mean erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level in the KD group were significantly higher than those in the viral and bacterial infection groups (P<0.001 and P<0.001 for ESR, P<0.001 and P=0.005 for CRP, respectively). The proportion of patients in the KD group with PCT levels of >1.0 ng/mL was significantly higher in the nonresponders to the initial intravenous immunoglobulin treatment than in the responders (36% vs. 8%, P=0.01).

Conclusion

PCT levels may help to differentiate KD from bacterial infections. A combination of disease markers, including ESR, CRP, and PCT, may be useful for differentiating between KD and viral/bacterial infections.

[Pathogens of infections in the induction period of childhood acute lymphoblastic leukemia and drug resistance of isolated strains]

OBJECTIVE

To investigate the infections occurring in the induction period of childhood acute lymphoblastic leukemia (ALL), the pathogens of the infections, and drug resistance of isolated strains.

METHODS

A retrospective analysis was performed for the clinical data of 130 children with newly-diagnosed childhood ALL. Infections occurring during the induction chemotherapy, pathogenic strains, and drug-resistance spectrum were analyzed.

RESULTS

The incidence rate of clinical infection and/or microbial infection reached 76.2%. The lungs were the most common infection site (46.2%). The children with severe infection accounted for 52.3%, among whom 60 had pulmonary infection and/or 21 had sepsis. A total of 50 pathogenic strains were detected, which consisted of 29 bacterial strains and 21 fungal strains. Of all the children, 28.5% experienced infections caused by at least one microbe. Among the 29 bacterial strains, there were 19 (65.5%) Gram-negative bacteria and 10 (34.5%) Gram-positive bacteria. The most common Gram-negative bacteria were Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa, which were 100% sensitive to imipenem. The most common Gram-positive bacterium was Streptococcus viridans, which was 100% sensitive to vancomycin. The infections caused by fungi accounted for 16.2%, with Candida albicans as the most common fungus. Compared with those with non-severe infections, the children with severe infections had a significantly shorter time to the occurrence of agranulocytosis, a significantly longer duration of agranulocytosis, significantly higher incidence of fever and C-reactive protein (CRP) level, and a significantly longer length of hospital stay (P<0.05).

CONCLUSIONS

Pulmonary infections are common in the induction period of childhood ALL. Gram-negative bacteria are the most common pathogenic bacteria. Severe infections can be controlled by carbapenems combined with vancomycin and antifungal agents.

Procalcitonin as a Marker of Bacteremia in Patients With Fever and Acute Lymphoblastic Leukemia

BACKGROUND

Children undergoing treatment for acute lymphoblastic leukemia (ALL) often present to the emergency department (ED) with a fever. They are at high risk of bacteremia secondary to being immunocompromised. Recent reports indicate that procalcitonin (PCT) is a useful marker of bacteremia in children.

OBJECTIVE

Our objective was to evaluate the clinical utility of PCT as a rapid marker of bacteremia in children with ALL presenting to the ED with a fever. In addition, we compared the results of PCT with white blood cell (WBC) count, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP).

METHODS

Retrospective chart reviews were conducted of 492 patients with a total of 735 visits presenting to the ED from January 2009 to June 2012 with fever and a history of ALL where a PCT and a blood culture (BC) were obtained,. Positive BCs determined to be contaminants were excluded. The predictive powers of PCT, WBC, ESR, and CRP for bacteremia were evaluated using the area under the receiver operating characteristic curve with 95% confidence intervals (CI). In addition, each of the 4 markers were also examined in a logistic regression model as a potential predictor of the BC result.

RESULTS

A total of 735 PCT values were correlated with BC results. There were 76 (10.3%) true-positive BCs. The area under the receiver operating characteristic curve was 0.729 (95% CI, 0.661-0.792) for PCT, 0.685 (95% CI, 0.531-0.823) for ESR, 0.622 (95% CI, 0.460-0.796) for CRP, and 0.567 (95% CI, 0.483-0.649) for WBC. When logistic regression was used, the transformation log PCT was significantly associated with BC result whereas each of the other 3 markers, after appropriate transformation to remove heavy skewness, was not significant (all P > 0.1). A doubling of PCT was associated with an odds ratio of 1.32 for positive BCs (95% CI, 1.15-1.53).

CONCLUSIONS

Procalcitonin value was significantly associated with positive BC (P < 0.0001). The diagnostic performance of PCT was better than the other markers of inflammation. Its use in the ED in a select population of patients may be of significant value in identifying bacteremia. This has the potential to lead to a decrease in unwarranted use of antibiotics, hospital length of stay, and health care expenditures.

Strong inflammatory response and Th1-polarization profile in children with acute lymphoblastic leukemia without apparent infection

Children with acute lymphoblastic leukemia (ALL) often present fever. Febrile states are usually associated with infectious processes that generate an inflammatory response involving various molecules, including cytokines. However, an inflammatory response may also occur in the absence of infection. We hypothesized that the levels of inflammatory cytokines are increased in children with ALL without apparent infection. The serum levels of 13 cytokines in 99 patients with ALL and 48 non-oncological patients without apparent infection were measured using multiplex analyte profiling technology (Luminex®). The concentration of circulating pro-inflammatory cytokines associated with fever was similar between patients with ALL and fever at diagnosis and those without fever. The levels of tumor necrosis factor α, interleukin (IL)-6, IL-8, monocyte chemoattractant protein-1 (MCP-1) and IL-10 were higher in patients with ALL vs. the control group (P<0.05). Moreover, the levels of the T helper 1 (interferon‑γ and IL-12) cytokines were higher in patients with ALL vs. the control group. Transforming growth factor β was lower in patients with ALL vs. the control group (P<0.05). The levels of IL-1β, IL-2, IL-4, IL-13, and IL-17 were similar in the two groups. Our results indicate that the circulating levels of seven of the important studied cytokines are elevated in patients with newly diagnosed ALL without apparent infection, reflecting a strong and deregulated inflammatory state in this disease, with a Th1-polarization profile.

Value of lipopolysaccharide binding protein as diagnostic marker of infection in adult cancer patients with febrile neutropenia: comparison with C-reactive protein, procalcitonin, and interleukin 6

PURPOSE

Early detection of infection is essential for initial management of cancer patients with chemotherapy-associated febrile neutropenia in the emergency department. In this study, we evaluated lipopolysaccharide binding protein (LBP) as predictor for infection in febrile neutropenia and compared with other biomarkers previously studied: C-reactive protein (CRP), procalcitonin (PCT), and interleukin (IL)-6.

METHODS

A total of 61 episodes of chemotherapy-associated febrile neutropenia in 58 adult cancer patients were included. Serum samples were collected on admission at emergency department and CRP, LBP, PCT, and IL-6 were measured. Patients were classified into fever of unknown origin and infection, including microbiologically and clinically documented infection, groups. Receiver operating characteristic (ROC) curve analysis was performed for each biomarker for the diagnosis of infection.

RESULTS

Thirty-two of the 61 episodes were classified as infection. On admission, CRP, PCT, IL-6, and LBP were significantly increased in patients with infection compared to fever of unknown origin group. Area under the ROC curve (AUC ROC) of CRP, PCT, IL-6, and LBP for discriminating both groups was 0.77, 0.88, 0.82, and 0.82, respectively, without significant difference between them. The combination of IL-6 and PCT or LBP did not lead to a significant improvement of the diagnostic accuracy of PCT or LBP alone.

CONCLUSIONS

On admission, LBP has a similar diagnostic accuracy than PCT or IL-6 for the diagnosis of infection and might be used as additional diagnostic tool in adult cancer patients with chemotherapy-associated febrile neutropenia.

The diagnostic value of cerebrospinal fluids procalcitonin and lactate for the differential diagnosis of post-neurosurgical bacterial meningitis and aseptic meningitis

OBJECTIVES

Distinguishing between post-neurosurgical bacterial meningitis (PNBM) and aseptic meningitis is difficult. This study aims to evaluate the combined diagnostic value of CSF procalcitonin and lactate as novel PNBM markers in hospitalized post-neurosurgery patients.

DESIGN AND METHODS

This study was performed using CSF samples, collected by lumbar puncture, from 178 PNBM-suspected patients enrolled in a retrospective clinical study. The levels of CSF procalcitonin and lactate were appropriately assayed and the combined diagnostic value of these markers was assessed using receiver operating characteristic (ROC) curves, a two by two table, and non-parametric tests.

RESULTS

Fifty of the 178 patients were diagnosed with PNBM, based on the clinical symptoms and laboratory results. These PNBM patients showed significantly elevated levels of CSF procalcitonin and CSF lactate compared with the non-PNBM group (p<0.001 for both). It was revealed that the cut-off values for the diagnosis of PNBM were: 0.075ng/mL (sensitivity, 68%; specificity, 73%) for procalcitonin and 3.45mmol/L (sensitivity, 90%; specificity, 85%) for lactate. A serial test combining the levels of these two markers showed decreased sensitivity (64%) and increased specificity (91%), compared with either marker alone. In contrast, a parallel test combining the levels of these both markers showed increased sensitivity (96%) and decreased specificity (65%), compared with either marker alone.

CONCLUSION

Our study shows that the combined use of CSF procalcitonin and lactate can reliably distinguish between PNBM and non-PNBM and can be included in the design of diagnostic approaches to circumvent the shortcomings of conventional methods.

Procalcitonin use in a pediatric intensive care unit

We evaluated whether procalcitonin (PCT) might aid diagnosing serious bacterial infections in a general pediatric intensive care unit population. Two-hundred and one patients accounted for 332 PCT samples. A PCT ≥1.45 ng/mL had a positive predictive value of 30%, a negative predictive value of 93% and a sensitivity of 72% and a specificity of 75%. These data suggest PCT can assist in identifying patients without serious bacterial infections and limit antimicrobial use.

Sensitivity and specificity of procalcitonin to determine etiology of diarrhea in children younger than 5 years

AIM

The aim of this study is to assess the sensitivity and specificity of procalcitonin to determine bacterial etiology of diarrhea.

THE EXAMINEES AND METHODS

For this purpose we conducted the study comprising 115 children aged 1 to 60 months admitted at the Department of Pediatric Gastroenterology, Pediatric Clinic, divided in three groups based on etiology of the diarrhea that has been confirmed with respective tests during the hospitalization. Each group has equal number of patients - 35. The first group was confirmed to have bacterial diarrhea, the second viral diarrhea and the third extra intestinal diarrhea. The determination of procalcitonin has been established with the ELFA methods of producer B.R.A.H.M.S Diagnostica GmbH, Berlin, (Germany).

RESULTS

From the total number of 1130 patient with acute diarrhea procalcitonin was assessed in 105. 67 (63.8%) of these patient were male. More than one third (38.14%) of the children in our study were younger then 12 months. Approximately the same was the number of children 13-24 months (33 patients or 31.43%) and 25-60 months (32 patients or 30.43%). The mean value of PRC in children with viral diarrhea was 0.13±0.5 ng/mL in children with bacterial diarrhea was 5.3±4.9 ng/m Land in children with extra intestinal diarrhea was 1.7±2.8 ng/mL. When measured using ANOVA and Turkey HSD tests, results have shown the statistical significance when comparing viral with bacterial and extra intestinal diarrhea but were statistically insignificant when comparing bacterial and extra intestinal diarrhea.

CONCLUSION

Procalcitonin is an important but not conclusive marker of bacterial etiology of acute diarrhea in children younger than 5 years.

Procalcitonin levels predict acute kidney injury and prognosis in acute pancreatitis: a prospective study

Background

Acute kidney injury (AKI) has been proposed as a leading cause of mortality for acute pancreatitis (AP) patients admitted to the intensive care unit (ICU). This study investigated the predictive value of procalcitonin (PCT) for AKI development and relevant prognosis in patients with AP, and compared PCT’s predictive power with that of other inflammation-related variables.

Methods

Between January 2011 and March 2013, we enrolled 305 cases with acute pancreatitis admitted to ICU. Serum levels of PCT, serum amyloid A (SAA), interleukin-6 (IL-6), and C reactive protein (CRP) were determined on admission. Serum PCT was tested in patients who developed AKI on the day of AKI occurrence and on either day 28 after occurrence (for survivors) or on the day of death (for those who died within 28 days).

Results

Serum PCT levels were 100-fold higher in the AKI group than in the non-AKI group on the day of ICU admission (p<0.05). The area under the receiver-operating characteristic (ROC) curve of PCT for predicting AKI was 0.986, which was superior to SAA, CRP, and IL-6 (p<0.05). ROC analysis revealed all variables tested had lower predictive performance for AKI prognosis. The average serum PCT level on day 28 (2.67 (0.89, 7.99) ng/ml) was significantly (p<0.0001) lower than on the day of AKI occurrence (43.71 (19.24,65.69) ng/ml) in survivors, but the serum PCT level on death (63.73 (34.22,94.30) ng/ml) was higher than on the day of AKI occurrence (37.55 (18.70,74.12) ng/ml) in non-survivors, although there was no significant difference between the two days in the latter group (p = 0.1365).

Conclusion

Serum PCT is superior to CRP, IL-6, and SAA for predicting the development of AKI in patients with AP, and also can be used for dynamic evaluation of AKI prognosis.

An updated systematic review and meta-analysis of the predictive value of serum biomarkers in the assessment of fever during neutropenia in children with cancer

BACKGROUND

Fever during neutropenia (FN) is a frequent and potentially life-threatening complication of the treatment of childhood cancer. The role of biomarkers in predicting morbidity and mortality associated with FN in children has been explored with varying results. This systematic review identified, critically appraised and synthesized information on the use of biomarkers for the prediction of outcome of FN in children/young adults, updating a review of initial assessment and adding further analysis of their value at reassessment.

METHODS

This review was conducted in accordance with the Centre for Reviews and Dissemination Methods, using 3 different random effects meta-analysis models.

RESULTS

Thirty-seven studies involving over 4689 episodes of FN in children were assessed, including an additional 13 studies investigating 18 biomarkers in 1670 FN episodes since the original review. Meta-analysis was possible for admission C-reactive protein (CRP), procalcitonin (PCT), interleukin-6 and interleukin-8 in their ability to detect significant infection. Marked heterogeneity exists, precluding clear clinical interpretation of the results. Qualitative synthesis of the role of serial biomarkers suggests their predictive ability may be more pronounced at 24 to 48 hours compared with admission. Direct comparisons of the discriminatory power of admission values of PCT and CRP showed PCT generally had a better discriminatory estimate of serious infection than CRP.

CONCLUSIONS

There remains a paucity of robust and reproducible data on the use of biomarkers in prediction of serious infection in children with FN. Available evidence suggests PCT has better discriminatory ability than CRP and that the role of serial biomarkers warrants further study.

Diagnostic accuracy of lipopolysaccharide-binding protein for predicting bacteremia/clinical sepsis in children with febrile neutropenia: comparison with interleukin-6, procalcitonin, and C-reactive protein

PURPOSE

In febrile neutropenia (FN), no reliable marker has been identified to discriminate between severe infection and other causes of fever early in the clinical course. Since lipopolysaccharide-binding protein (LBP) has proven to be an accurate biomarker of bacteremia/clinical sepsis in critically ill non-immunocompromised infants and children, we performed a prospective study to determine the diagnostic accuracy of LBP in children with FN.

METHODS

Concentrations of LBP, procalcitonin (PCT), interleukin-6 (IL-6), and C-reactive protein (CRP) were prospectively measured on two consecutive days in 90 FN episodes experienced by 47 children. Receiver operating characteristic curve analysis was performed for each biomarker to predict bacteremia/clinical sepsis and severe sepsis.

RESULTS

Eighteen of the 90 episodes were classified as bacteremia/clinical sepsis. On both days 1 and 2, all biomarkers had a low to intermediate diagnostic accuracy for sepsis, and no significant differences were found between them (area under the curve (AUC) for LBP, 0.648 and 0.714; for PCT, 0.665 and 0.744; for IL-6, 0.775 and 0.775; and for CRP, 0.695 and 0.828). Comparison of their AUCs to the AUC of maximum body temperature on admission (AUC = 0.668) also failed to show any significant differences. In severe sepsis, however, the best diagnostic accuracies were found for IL-6 and PCT (AUC 0.892 and 0.752, respectively), and these were significantly higher than those for LBP (AUC 0.566) on admission.

CONCLUSIONS

On admission and 24 h later, the LBP concentration is less accurate for predicting bacteremia/clinical sepsis compared to IL-6, PCT, and CRP.

Procalcitonin in pediatrics

Over the past two decades, the body of literature on the clinical usefulness of procalcitonin (PCT) in adults has grown rapidly. Although this approach has led to increased insight, it has also prompted debate regarding its potential use in diagnosis and management of severe infection. Clinicians, however, are less familiar with the use of PCT in pediatric populations. In this review, we examine PCT as a marker of severe clinical pediatric conditions including its role in systemic inflammation, infection, and sepsis.

Procalcitonin as a marker of bacteremia in children with fever and a central venous catheter presenting to the emergency department

OBJECTIVE

To evaluate the clinical use of procalcitonin (PCT) as a rapid marker for the identification of bacteremia in the emergency department (ED) population of children with fever and a central venous catheter (CVC).

METHODS

Children were identified on presentation to the ED with a chief complaint of fever and who had a CVC. Fever was defined as 38°C or higher orally. Patients were excluded from the study if they had received antibiotics within the previous 24 hours of presenting to the ED, if they had a peripherally inserted central catheter line or by parental refusal. On presentation to the ED, all patients had a complete blood cell count with differential, blood culture from the central line, and PCT levels drawn. All had empiric antibiotics initiated. Blood culture results were recorded, and in the case of positive cultures, time to positive culture was noted.

RESULTS

Sixty-two patients (aged 5 months-18 y) were enrolled, and 14 (23%) had a positive culture. Mean PCT value in bacteremic patients was 18.47 ± 31.6 ng/mL and 0.65 ± 1.2 ng/mL in nonbacteremic patients (P < 0.001). Median PCT for negative blood culture was 0.23 ng/mL (interquartile range, 0.11-0.61) and 1.15 ng/mL for a positive blood culture (interquartile range, 0.45-29.16). The receiver operating characteristic analysis identified a level of PCT of 0.3 ng/mL as the best cutoff point that produced a sensitivity of 93% and a specificity of 63% (area under the curve, 0.82).

CONCLUSIONS

The PCT levels are useful in identifying children with fever and a CVC who are bacteremic in the ED.

IL-10 combined with procalcitonin improves early prediction of complications of febrile neutropenia in hematological patients

Early diagnosis of complicated course in febrile neutropenia is cumbersome due to the non-specificity of clinical and laboratory signs of severe infection. This prospective study included 100 adult hematological patients with febrile neutropenia after intensive chemotherapy at the onset of fever (d0) and for 3 days (d1-d3) thereafter. The study aim was to find early predictors for complicated course of febrile neutropenia, defined as bacteremia or septic shock. Interleukin 6 (IL-6), interleukin 10 (IL-10), procalcitonin (PCT) and C-reactive protein (CRP) all predicted complicated course of febrile neutropenia on d0, but only PCT was predictive throughout the study period. For IL-10 on d0-1 with cut-off 37 ng/L, sensitivity was 0.71, specificity 0.82, positive predictive value 0.52 and negative predictive value 0.92. For PCT on d0-1 with cut-off 0.13 μg/L, the respective measures were 0.95, 0.53, 0.36, and 0.98. For the combination of IL-10 and PCT on d0-1 with the same cut-offs, specificity improved to 0.85 and positive predictive value to 0.56. In conclusion, the present study confirms the high negative predictive value of PCT and provides new evidence for IL-10 as an early predictor for complicated course of febrile neutropenia in hematological patients. Combining IL-10 with PCT improves the early prediction for complicated course of febrile neutropenia.

Predictive factors for poor prognosis febrile neutropenia

PURPOSE OF REVIEW

Most patients with chemotherapy-induced febrile neutropenia recover rapidly without serious complications. However, it still remains a life-threatening treatment-related toxicity, and is associated with dose reductions and delays of chemotherapeutic agents that may compromise treatment outcomes. Recent developments of risk stratification enabled early discharge with oral antibiotics for low-risk patients. However, even in low-risk patients, medical complications including bacteremia could happen. The authors reviewed recent literature to provide an update on research regarding predictive factors for poor prognosis in patients with febrile neutropenia.

RECENT FINDINGS

Various prognostic factors have been suggested with controversies. Hematological parameters, prophylactic measurements and patient-specific risk factors showed inconsistent results. MASCC risk-index score, which was originally developed to identify low-risk patients, in turn showed that the lower the MASCC score, the poorer the prognosis of febrile neutropenia, with very low levels (<15), the rate of complications was high. Patients with severe sepsis and septic shock commonly had procalcitonin concentration above 2.0 ng/ml, and this level should be considered at high risk of poor prognosis.

SUMMARY

Lower MASCC score and higher procalcitonin concentration can predict poor outcomes in febrile neutropenia. More research is required with regard to the other factors showing controversies.

Biomarkers for risk stratification of febrile neutropenia among children with malignancy: a pilot study

BACKGROUND

Patients receiving myelosuppressive chemotherapy remain at increased risk for developing febrile neutropenia (FN). For this heterogeneous population, a biomarker based risk stratification of FN patients may be a useful clinical tool. We hypothesized that serum biomarkers during initial presentation of an FN event could be predictive of subsequent clinical outcome.

PROCEDURE

Eighty-nine FN events from 36 non-consecutive subjects were analyzed. "High-risk" FN criteria included prolonged hospitalization (≥ 7 days), admission to pediatric intensive care unit (PICU) or a microbiology confirmed bacteremia. Patients with "low risk" FN had none of the above. Biomarkers measured during the first 2 days of FN hospitalization were analyzed and correlated with respective clinical outcome.

RESULTS

Of the 89 FN events, 44 (49%) fulfilled pre-defined high-risk criteria and 45 (51%) were low-risk. Procalcitonin level (>0.11 ng/ml) was found to be associated with the high-risk FN outcome with sensitivity of 97%. With an increase in log scale by 1, the odds of being high-risk FN increased twofold. Hs-CRP >100 mg/L had sensitivity of 88% in predicting high-risk FN. The odds of a high-risk FN event increased by approximately 1.8-fold with an increase in the log scale of hs-CRP by 1 (10-fold). In univariate analysis, IL-6, IL-8, and IL-10 were statistically significant and associated with high-risk FN. However, no statistically significant difference was found for IL-1α, sIL-2Ra, IL-3, or TNF-α.

CONCLUSIONS

Biomarkers with appropriate critical threshold values may be a useful clinical tool for appropriate risk stratification of children with FN.

Immune regulation of procalcitonin: a biomarker and mediator of infection

Procalcitonin (PCT) has recently emerged as a powerful biomarker for an early and accurate diagnosis of bacterial infection. Here we summarize our current understanding of the expression pathways of PCT, its potential cellular sources including immune cells, and factors inducing its secretion. Also addressed is the significance of increased blood PCT concentration, which may allow this molecule not only to act as a clinical biomarker but also as an active participant in the development and progression of infectious processes. Experimental approaches to delineate a better understanding of PCT functions, molecular pathways that modulate its expression and therapeutic opportunities to curtail its biological actions are discussed, as well.

New molecular and surrogate biomarker-based tests in the diagnosis of bacterial and fungal infection in febrile neutropenic patients

PURPOSE OF REVIEW

Prompt diagnosis of infection in febrile neutropenia hosts with hematological malignancy is essential in directing therapy. We highlight experience using modern molecular and biomarker-based methods to diagnose bacterial and fungal bloodstream infections and invasive aspergillosis in these patients.

RECENT FINDINGS

Nucleic acid amplification-based strategies are used to detect and identify pathogens from blood cultures or from blood/clinical specimens; the latter are more likely to influence clinical management. Advances in DNA extraction include standardization of isolation of Aspergillus DNA from blood. Broad-range and/or multiplex PCR generally have greater clinical utility than pathogen-specific assays. However, Aspergillus-PCR assays are useful in confirming/excluding disease and monitoring high-risk patients for invasive aspergillosis. Commercial real-time PCR/peptide nucleic acid fluorescent in-situ hybridization systems, used as adjuncts to blood cultures, to detect bacteria and fungi in blood cultures (or blood), are as sensitive as culture and enable earlier institution of targeted therapy. Yet there are no data indicating that molecular detection of bacterial/fungal pathogens influences patient outcomes. Positive serum Aspergillus galactomannan and 1,3-β-D-glucan tests are useful biomarkers in the diagnosis/screening of fungal infection, and have potential as measures of response to antifungal therapy. Serum procalcitonin levels can help differentiate infectious, from noninfectious, fever. Combined molecular and nonmolecular testing likely offers optimal diagnostic accuracy.

SUMMARY

Numerous PCR-based and biomarker tools are available for the diagnosis and screening of infection in febrile neutropenia hosts. The optimal approach remains to be resolved by prospective studies examining the impact of one or more of tests on patient outcomes.

Biomarkers for pediatric sepsis and septic shock

Sepsis is a clinical syndrome defined by physiologic changes indicative of systemic inflammation, which are likely attributable to documented or suspected infection. Septic shock is the progression of those physiologic changes to the extent that delivery of oxygen and metabolic substrate to tissues is compromised. Biomarkers have the potential to diagnose, monitor, stratify and predict outcome in these syndromes. C-reactive protein is elevated in inflammatory and infectious conditions and has long been used as a biomarker indicating infection. Procalcitonin has more recently been shown to better distinguish infection from inflammation. Newer candidate biomarkers for infection include IL-18 and CD64. Lactate facilitates the diagnosis of septic shock and the monitoring of its progression. Multiple stratification biomarkers based on genome-wide expression profiling are under active investigation and present exciting future possibilities.

The diagnostic value of CRP, IL-8, PCT, and sTREM-1 in the detection of bacterial infections in pediatric oncology patients with febrile neutropenia

Purpose

In this study, we evaluated C-reactive protein (CRP), interleukin (IL)-8, procalcitonin (PCT), and soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) as predictors for bacterial infection in febrile neutropenia, plus their usefulness in febrile neutropenia during chemotherapy-induced gastrointestinal mucositis.

Methods

Plasma was obtained from pediatric oncology patients at presentation with febrile neutropenia (n = 43) and 24–48 h later (n = 17). The patients were classified as having or not having a bacterial infection. Plasma was also obtained of patients in the absence and in the presence of mucositis (n = 26).

Results

At presentation with febrile neutropenia, median IL-8 and PCT levels were significantly increased in patients with a bacterial infection, in contrast to CRP and sTREM-1. IL-8 was the most sensitive marker for the early detection of bacterial infection, in combination with clinical parameters or PCT the sensitivity reached 100%. After 24–48 h, only PCT was significantly elevated during bacterial infection. IL-8 levels were significantly increased during mucositis. Mucositis did not cause considerable changes in PCT levels.

Conclusions

IL-8 is the most useful marker for the early detection of bacterial infections, compared with CRP, PCT, and sTREM-1. IL-8 in combination with clinical parameters or PCT might be even more useful. Gastrointestinal mucositis alone does not affect PCT levels, in contrast to IL-8 levels, and therefore, PCT might be more useful for the detection of bacterial infections during mucositis than IL-8.