Procalcitonin as an early marker of infection in neonates and children

A Clinical Prediction Rule to Identify Febrile Infants 60 Days and Younger at Low Risk for Serious Bacterial Infections

IMPORTANCE

In young febrile infants, serious bacterial infections (SBIs), including urinary tract infections, bacteremia, and meningitis, may lead to dangerous complications. However, lumbar punctures and hospitalizations involve risks and costs. Clinical prediction rules using biomarkers beyond the white blood cell count (WBC) may accurately identify febrile infants at low risk for SBIs.

OBJECTIVE

To derive and validate a prediction rule to identify febrile infants 60 days and younger at low risk for SBIs.

DESIGN, SETTING, AND PARTICIPANTS

Prospective, observational study between March 2011 and May 2013 at 26 emergency departments. Convenience sample of previously healthy febrile infants 60 days and younger who were evaluated for SBIs. Data were analyzed between April 2014 and April 2018.

EXPOSURES

Clinical and laboratory data (blood and urine) including patient demographics, fever height and duration, clinical appearance, WBC, absolute neutrophil count (ANC), serum procalcitonin, and urinalysis. We derived and validated a prediction rule based on these variables using binary recursive partitioning analysis.

MAIN OUTCOMES AND MEASURES

Serious bacterial infection, defined as urinary tract infection, bacteremia, or bacterial meningitis.

RESULTS

We derived the prediction rule on a random sample of 908 infants and validated it on 913 infants (mean age was 36 days, 765 were girls [42%], 781 were white and non-Hispanic [43%], 366 were black [20%], and 535 were Hispanic [29%]). Serious bacterial infections were present in 170 of 1821 infants (9.3%), including 26 (1.4%) with bacteremia, 151 (8.3%) with urinary tract infections, and 10 (0.5%) with bacterial meningitis; 16 (0.9%) had concurrent SBIs. The prediction rule identified infants at low risk of SBI using a negative urinalysis result, an ANC of 4090/µL or less (to convert to ×109 per liter, multiply by 0.001), and serum procalcitonin of 1.71 ng/mL or less. In the validation cohort, the rule sensitivity was 97.7% (95% CI, 91.3-99.6), specificity was 60.0% (95% CI, 56.6-63.3), negative predictive value was 99.6% (95% CI, 98.4-99.9), and negative likelihood ratio was 0.04 (95% CI, 0.01-0.15). One infant with bacteremia and 2 infants with urinary tract infections were misclassified. No patients with bacterial meningitis were missed by the rule. The rule performance was nearly identical when the outcome was restricted to bacteremia and/or bacterial meningitis, missing the same infant with bacteremia.

CONCLUSIONS AND RELEVANCE

We derived and validated an accurate prediction rule to identify febrile infants 60 days and younger at low risk for SBIs using the urinalysis, ANC, and procalcitonin levels. Once further validated on an independent cohort, clinical application of the rule has the potential to decrease unnecessary lumbar punctures, antibiotic administration, and hospitalizations.

Gestational diabetes mellitus increases the baseline level of procalcitonin in maternal blood but not in umbilical cord blood in late pregnancy: A retrospective case-controlled study

To study the effects of gestational diabetes mellitus (GDM) on the level of procalcitonin (PCT) in maternal blood and umbilical cord blood in late-pregnant women.We retrospectively analyzed 37 pregnant women in late pregnancy who had GDM and compared with those of 97 age-matched normal glucose-tolerant (NGT) pregnant women. The PCT level was converted to a value with normal distribution (LG-PCT) by taking the logarithm of each value to the base 10 (log10).The body mass index (BMI) before delivery, family history of diabetes mellitus (DM), and postpartum blood loss within 24 hours were markedly higher in GDM group than in NGT group, while the gestational age was smaller in GDM group than in NGT group. The maternal blood LG-PCT was significantly higher in GDM group than in NGT group, while the umbilical cord blood LG-PCT was not significantly different between the 2 groups. Multivariate analysis showed that family history of DM, gestational age, and maternal blood LG-PCT were independent risk factors of GDM after adjusting for BMI and postpartum blood loss within 24 hours.GDM increases the baseline level of maternal blood PCT but has little effect on umbilical cord blood PCT.

Presepsin: A promising biomarker for the detection of bacterial infections

Appropriate recognition of bacterial infections in health care setting is the basis for effective treatment and control of infectious diseases. The positivity rate of traditional methods is low and is influenced by quality and quantity of specimens, patient antibiotic administration, severity of infection, and laboratory sufficiency. Currently, there are novel non-culture-based techniques that are being accomplished to improve the identification of infections. Several immunologic biomarkers have been assessed to develop the best indicator of infections. Presepsin is an immunologic biomarker which has been demonstrated as new, emerging, early indicator for the detection of different infections. The biological function of presepsin is not well known. However, it is believed that it may be a regulatory molecule of the adaptive immune system and also a stimulator of monocyte phagocytosis. The early increased levels of presepsin during the sepsis and other bacterial infections have made it an attractive indicator for laboratory testing. Several studies have investigated the capacity of presepsin for use in clinical settings. The aim of the present study was review the clinical application of presepsin in diagnosis and prediction of infections. To achieve this objective, the documents on diagnostic and clinical assessment were evaluated in PubMed and Scopus databases regarding the use of presepsin as indicators of infections.

The Physiological Variation in Plasma Presepsin Levels During the Early Neonatal Period

Neonatal sepsis continues to be a global problem with significant morbidity and mortality, because of the difficulty in predicting its onset with clinical symptoms alone. Thus, the presence of biomarkers is useful for the diagnosis of neonatal sepsis. Presepsin is a 13-kDa truncated form of soluble CD14 that is produced through proteolytic cleavage on activated monocytes. Presepsin, consisting of 64 amino acid residues, has been proposed as a reliable biomarker for the early diagnosis of sepsis in neonates. However, some biomarkers for the diagnosis of sepsis are elevated during the early neonatal period due to physiological variation, whereas such variation in presepsin levels is uncertain. The objective of this study is to investigate the physiological variation in plasma presepsin levels during the early neonatal period. This prospective study included 30 full-term healthy neonates, including 15 neonates delivered by cesarean section. Plasma presepsin levels were examined at birth and on the first day and the fifth day of life in neonates, and the levels on the 5th day of life were lower than those at any other points (P < 0.001). Moreover, there was no significant difference of plasma presepsin levels between neonates delivered vaginally and by cesarean section. The physiological variation in plasma presepsin levels was observed during the early neonatal period. Attention needs to be paid when measuring plasma presespsin levels for the screening of sepsis during the early neonatal period.

Associations of Neighborhood-Level Social Determinants of Health with Bacterial Infections in Young, Febrile Infants

OBJECTIVE

To examine the sociodemographic characteristics of one population of young, febrile infants and identify associations between neighborhood-level social determinants of health (SDHs) with bacterial infections.

STUDY DESIGN

This was a retrospective cross sectional study of all infants ≤90 days old with a temperature of ≥38°C who presented in 2014 to the emergency department of an urban children's hospital in a large east coast city. The primary outcome was the presence of a bacterial infection, defined as a positive urine, blood, or cerebrospinal fluid culture that was treated clinically as a pathogen. The home address of each infant was geocoded and linked to neighborhood data based on census tract. Neighborhood-level SDHs included deprivation index, median household income, poverty, childhood poverty, social capital, and crowded housing. Associations were estimated using generalized estimating equations and negative binomial regression analysis. Models were adjusted for age, prematurity, and race/ethnicity.

RESULTS

Of 232 febrile infants, the median age was 54 days, 58% were male, 49% were Hispanic, and 88% had public health insurance; 31 infants (13.4%) had a bacterial infection. In the adjusted analyses, the risk of bacterial infection among infants from neighborhoods with high rates of childhood poverty was >3 times higher (relative risk, 3.16; 95% CI, 1.04-9.6) compared with infants from neighborhoods with low rates of childhood poverty.

CONCLUSIONS

Our findings suggest that SDHs may be associated with bacterial infections in young, febrile infants. If confirmed in subsequent studies, the inclusion of SDHs in predictive tools may improve accuracy in detecting bacterial infections among young, febrile infants.

The combination of procalcitonin and C-reactive protein or presepsin alone improves the accuracy of diagnosis of neonatal sepsis: a meta-analysis and systematic review

Background

Sepsis is an important cause of neonatal morbidity and mortality; therefore, the early diagnosis of neonatal sepsis is essential.

Method

Our aim was to compare the diagnostic accuracy of procalcitonin (PCT), C-reactive protein (CRP), procalcitonin combined with C-reactive protein (PCT + CRP) and presepsin in the diagnosis of neonatal sepsis. We searched seven databases to identify studies that met the inclusion criteria. Two independent reviewers performed data extraction. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), area under curve (AUC), and corresponding 95% credible interval (95% CI) were calculated by true positive (TP), false positive (FP), false negative (FN), and true negative (TN) classification using a bivariate regression model in STATA 14.0 software. The pooled sensitivity, specificity, PLR, NLR, DOR, AUC, and corresponding 95% CI were the primary outcomes. Secondary outcomes included the sensitivity and specificity in multiple subgroup analyses.

Results

A total of 28 studies enrolling 2661 patients were included in our meta-analysis. The pooled sensitivity of CRP (0.71 (0.63, 0.78)) was weaker than that of PCT (0.85 (0.79, 0.89)), PCT + CRP (0.91 (0.84, 0.95)) and presepsin (0.94 (0.80, 0.99)) and the pooled NLR of presepsin (0.06 (0.02, 0.23)) and PCT + CRP (0.10 (0.05, 0.19)) were less than CRP (0.33 (0.26, 0.42)), and the AUC for presepsin (0.99 (0.98, 1.00)) was greater than PCT + CRP (0.96 (0.93, 0.97)), CRP (0.85 (0.82, 0.88)) and PCT (0.91 (0.89, 0.94)). The results of the subgroup analysis showed that 0.5–2 ng/mL may be the appropriate cutoff interval for PCT. A cut-off value > 10 mg/L for CRP had high sensitivity and specificity.

Conclusions

The combination of PCT and CRP or presepsin alone improves the accuracy of diagnosis of neonatal sepsis. However, further studies are required to confirm these findings.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2236-1) contains supplementary material, which is available to authorized users.

Time-to-Positivity of Blood Cultures in Children With Sepsis

Background: Blood cultures are essential for the diagnosis and further appropriate treatment in children with suspected sepsis. In most hospitals, children will be empirically treated or closely monitored for at least 48 h awaiting results of blood cultures. Several studies have challenged the optimal duration of empiric treatment in the era of continuously monitored blood culture systems. The aim of our study was to investigate time-to-positivity (TTP) of blood cultures in children with proven sepsis. Methods: The Swiss Pediatric Sepsis Study prospectively enrolled children 0-16 years of age with blood culture positive sepsis between September 2011 and October 2015. TTP was prospectively assessed in six participating academic pediatric hospitals by fully automated blood culture systems. Results: In 521 (93%) of 562 bacteremia episodes (493 children, median age 103 days, range 0 days-16.9 years) a valid TTP was available. Median TTP was 12 h (IQR 8-17 h, range 0-109 h). By 24, 36, and 48 h, 460 (88%), 498 (96%), and 510 (98%) blood cultures, respectively, were positive. TTP was independent of age, sex, presence of comorbidities, site of infection and severity of infection. Median TTP in all age groups combined was shortest for group B streptococcus (8.7 h) and longest for coagulase-negative staphylococci (16.2 h). Conclusion: Growth of bacteria in blood cultures is detectable within 24 h in 9 of 10 children with blood culture-proven sepsis. Therefore, a strict rule to observe or treat all children with suspected sepsis for at least 48 h is not justified.

Is Procalcitonin Useful in Pediatric Critical Care Patients?

This review examines the use of procalcitonin in different clinical situations in the pediatric patient, with special emphasis on those requiring intensive care. We review the latest articles on its potency as a biomarker in both infectious processes at diagnosis and on the response to treatment.

Effect of the Procalcitonin Assay on Antibiotic Use in Critically Ill Children

We retrospectively studied the effect of introducing procalcitonin into clinical practice on antibiotic use within a large academic pediatric intensive care unit. In the absence of a standardized algorithm, availability of the procalcitonin assay did not reduce the frequency of antibiotic initiations or the continuation of antibiotics for greater than 72 hours.

Refined Lab-score, a Risk Score Predicting Serious Bacterial Infection in Febrile Children Less Than 3 Years of Age

BACKGROUND

The identification of serious bacterial infection (SBI) in children with fever without source remains a challenge. A risk score called Lab-score, based on C-reactive protein, procalcitonin and urinary dipstick results was derived to predict SBI. However, all biomarkers were initially dichotomized, leading to weak statistical reliability and lack of transportability across diverse settings. We aimed to refine and validate this risk-score algorithm.

METHODS

The Lab-score was refined using a secondary analysis of a multicenter cohort study of children with fever without source via multilevel regression modeling. The external validation was conducted on data from a Canadian cohort study.

RESULTS

Eight hundred seventy-seven children (24% SBI) were included for the derivation study, and 347 (16% SBI) for validation. Only C-reactive protein, procalcitonin, age and urinary dipstick remained independently associated with SBI. The model achieved an area under the receiver operating characteristic (ROC) curve of 0.94 (95% confidence interval [CI]: 0.93-0.96), which was significantly higher than any other isolated biomarker (P < 0.0001), and the original Lab-score (P < 0.0001). According to a decision curve analysis, the model yielded a better strategy than those based on independently considered biomarkers, or on the original Lab-score. The threshold analysis led to a cutoff that yielded 96% (95% CI: 92-98) sensitivity and 73% (95% CI: 70-77) specificity. The external validation found similar predictive abilities: 0.96 area under the ROC curve (95% CI: 0.93-0.99), 95% sensitivity (95% CI: 85-99) and 87% specificity (95% CI: 83-91).

CONCLUSION

The refined Lab-score demonstrated higher prediction ability for SBI than the original Lab-score, with promising wider applicability across settings. These results require validation in additional populations.

Evaluation of a real-time PCR assay for detection and quantification of bacterial DNA directly in blood of preterm neonates with suspected late-onset sepsis

Background

Rapid and accurate diagnosis of neonatal sepsis is highly warranted because of high associated morbidity and mortality. The aim of this study was to evaluate the performance of a novel multiplex PCR assay for diagnosis of late-onset sepsis and to investigate the value of bacterial DNA load (BDL) determination as a measure of infection severity.

Methods

This cross-sectional study was conducted in a neonatal intensive care unit. Preterm and/or very low birth weight infants suspected for late-onset sepsis were included. Upon suspicion of sepsis, a whole blood sample was drawn for multiplex PCR to detect the eight most common bacteria causing neonatal sepsis, as well as for blood culture. BDL was determined in episodes with a positive multiplex PCR.

Results

In total, 91 episodes of suspected sepsis were investigated, and PCR was positive in 53 (58%) and blood culture in 60 (66%) episodes, yielding no significant difference in detection rate (p = 0.17). Multiplex PCR showed a sensitivity of 77%, specificity of 81%, positive predictive value of 87%, and negative predictive value of 68% compared with blood culture. Episodes with discordant results of PCR and blood culture included mainly detection of coagulase-negative staphylococci (CoNS). C-reactive protein (CRP) level and immature to total neutrophil (I/T) ratio were lower in these episodes, indicating less severe disease or even contamination. Median BDL was high (4.1 log₁₀ cfu Eq/ml) with a wide range, and was it higher in episodes with a positive blood culture than in those with a negative blood culture (4.5 versus 2.5 log₁₀ cfu Eq/ml; p < 0.0001). For CoNS infection episodes BDL and CRP were positively associated (p = 0.004), and for Staphylococcus aureus infection episodes there was a positive association between BDL and I/T ratio (p = 0.049).

Conclusions

Multiplex PCR provides a powerful assay to enhance rapid identification of the causative pathogen in late-onset sepsis. BDL measurement may be a useful indicator of severity of infection.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2010-4) contains supplementary material, which is available to authorized users.

The diagnostic utility of procalcitonin, interleukin-6 and interleukin-8, and hyaluronic acid in the Norwegian consensus definition for early-onset neonatal sepsis (EONS)

Introduction

A key challenge in identifying serious bacterial infection in new born infants is the nonspecific clinical presentation of early-onset neonatal sepsis (EONS). Routinely used C-reactive protein, white blood cell count, and platelets are nonspecific. We assessed the diagnostic utility of single biomarkers or combinations of procalcitonin (PCT), interleukin (IL)-6, IL-8, and hyaluronic acid (HA) in newborn infant with EONS, and in human umbilical cord blood (HUCB) from deliveries with chorioamnionitis.

Materials and methods

Blood was collected from term infants with strictly defined EONS (group 1, n=15), healthy term infants (group 2, n=15), and the umbilical vein from pregnancies with suspected chorioamnionitis (group 3, n=8), and from healthy pregnancies with no signs of infection (group 4, n=15).

Results

Neonatal plasma PCT and IL-8 showed good predictive value (90% and 83%) for EONS, and the combination of IL-6 or HA with PCT increased the predictability to 87% and 90%, respectively. PCT, IL-6, IL-8, and HA were 8.4-, 4.5-, 3.6-, and 1.9-fold higher when compared with plasma levels in noninfected neonates. PCT, IL-6, and IL-8 in HUCB predicted chorioamnionitis and fever in the delivering mother (89%, 83%, and 72%, respectively). HA was a poor predictor (59%), but its predictability increased in combination with PCT, IL-8, or IL-6. In HUCB from chorioamnionitic deliveries, IL-6, IL-8, and PCT were 23-, 14-, and 2.4-fold higher, respectively, when compared with HUCB from healthy deliveries. There was no correlation between C-reactive protein, white blood cell, and platelet count with PCT, IL-6, IL-8, or HA.

Conclusion

In neonates that fulfilled the Norwegian consensus definition of neonatal sepsis, PCT, IL-6, and IL-8, but not HA, have the potential to improve our management of neonates at risk. Except for PCT and IL-8, both with a predictability of >80% in neonatal plasma, combinations of biomarkers increased the predictability for EONS and chorioamnionitis.

Validation of the Feverkidstool and procalcitonin for detecting serious bacterial infections in febrile children

BackgroundTo validate the Feverkidstool, a prediction model consisting of clinical signs and symptoms and C-reactive protein (CRP) to identify serious bacterial infections (SBIs) in febrile children, and to determine the incremental diagnostic value of procalcitonin.MethodsThis prospective observational study that was carried out at two Dutch emergency departments included children with fever, aged 1 month to 16 years. The prediction models were developed with polytomous logistic regression differentiating "pneumonia" and "other SBIs" from "non-SBIs" using standardized, routinely collected data on clinical signs and symptoms, CRP, and procalcitonin.ResultsA total of 1,085 children were included with a median age of 1.6 years (interquartile range 0.8-3.4); 73 children (7%) had pneumonia and 98 children (9%) had other SBIs. The Feverkidstool showed good discriminative ability in this new population. After adding procalcitonin to the Feverkidstool, c-statistic for "pneumonia" increased from 0.85 (95% confidence interval (CI) 0.76-0.94) to 0.86 (0.77-0.94) and for "other SBI" from 0.81 (0.73-0.90) to 0.83 (0.75- 0.91). A model with clinical features and procalcitonin performed similar to the Feverkidstool.ConclusionThis study confirms the external validity of the Feverkidstool, with CRP and procalcitonin being equally valuable for predicting SBI in our population of febrile children. Our findings do not support routine dual use of CRP and procalcitonin.

Culture-Negative Early-Onset Neonatal Sepsis - At the Crossroad Between Efficient Sepsis Care and Antimicrobial Stewardship

Sepsis is a leading cause of mortality and morbidity in neonates. Presenting clinical symptoms are unspecific. Sensitivity and positive predictive value of biomarkers at onset of symptoms are suboptimal. Clinical suspicion therefore frequently leads to empirical antibiotic therapy in uninfected infants. The incidence of culture confirmed early-onset sepsis is rather low, around 0.4-0.8/1000 term infants in high-income countries. Six to 16 times more infants receive therapy for culture-negative sepsis in the absence of a positive blood culture. Thus, culture-negative sepsis contributes to high antibiotic consumption in neonatal units. Antibiotics may be life-saving for the few infants who are truly infected. However, overuse of broad-spectrum antibiotics increases colonization with antibiotic resistant bacteria. Antibiotic therapy also induces perturbations of the non-resilient early life microbiota with potentially long lasting negative impact on the individual's own health. Currently there is no uniform consensus definition for neonatal sepsis. This leads to variations in management. Two factors may reduce the number of culture-negative sepsis cases. First, obtaining adequate blood cultures (0.5-1 mL) at symptom onset is mandatory. Unless there is a strong clinical or biochemical indication to prolong antibiotics physician need to trust the culture results and to stop antibiotics for suspected sepsis within 36-48 h. Secondly, an international robust and pragmatic neonatal sepsis definition is urgently needed. Neonatal sepsis is a dynamic condition. Rigorous evaluation of clinical symptoms ("organ dysfunction") over 36-48 h in combination with appropriately selected biomarkers ("dysregulated host response") may be used to support or refute a sepsis diagnosis.

Procalcitonin: The marker of pediatric bacterial infection

Timely recognition of systemic bacterial infections in pediatric care setting is the basis for effective treatment and control. This review provides an overview of procalcitonin (PCT) as an early marker for the detection of severe, invasive bacterial infection in children. Almost all articles on biochemical property and clinical studies in PubMed and Scopus databases regarding their use in pediatric infections and the use of PCT as a marker of bacterial infections were examined. Various methods and analyzers are currently available for the evaluation of PCT. Employment of PCT in the identification of neonatal bacterial infection is a complex process in some conditions. Age specific cut-off, underlying syndrome, and maternal antibiotics usage should be considered when PCT is to be applied in neonates. PCT might be false-negative in these conditions. However, if used appropriately, it can lead to a higher specificity than other immunologic markers. Due to its correlation with the severity of infection, PCT can consequently be used as a prognostic indicator especially for sepsis and urinary tract infection. It is, therefore, a practical supplementary means for the identification of bacterial infections in pediatric health settings.

Predictive value of procalcitonin for intestinal ischemia and/or necrosis in pediatric patients with adhesive small bowel obstruction (ASBO)

PURPOSE

Evaluate serum procalcitonin (PCT) level as a predictor of intestinal ischemia or necrosis (IN) in patients with postoperative adhesive small bowel obstruction (ASBO).

METHODS

Prospective cohort of consecutive patients with ASBO. Patients previously treated with antibiotics or septic were excluded. PCT was measured at the diagnosis of ASBO and every 24 h afterwards.

MAIN OUTCOME

intestinal ischemia or necrosis (IN).

RESULTS

Fifty-nine patients were included, 12 of whom were excluded; 47 patients remained in the study; male-to-female ratio = 1.9:1.

MANAGEMENT

medical in 15 cases (32%) and surgical in 32 (68%).

MAIN OUTCOME

Intestinal necrosis (IN) in 10 patients (21.3%). Mean PCT level was higher in patients with IN (15.11 ng/ml vs. 0.183 ng/ml, p=0.002), the proportion of patients with elevated PCT (>0.5 ng/dl) was higher in patients with IN (70% vs. 8.1%, p=<0.001, RR=26.4 with a 95% CI of 4.39-159.5). Elevated PCT levels at diagnosis had a 70% positive predictive value (PPV) and 91.8% negative predictive value (NPV) for prediction of IN. With a PCT value at diagnosis of >1.0 ng/dl, PPV was 87.5% and NPV, 92.3%.

CONCLUSIONS

PCT levels are closely related to the presence of intestinal ischemia and necrosis in children with ASBO.

LEVEL OF EVIDENCE

Study of Diagnostic Test, Level II.

Procalcitonin-guided decision making for duration of antibiotic therapy in neonates with suspected early-onset sepsis: a multicentre, randomised controlled trial (NeoPIns)

BACKGROUND

Up to 7% of term and late-preterm neonates in high-income countries receive antibiotics during the first 3 days of life because of suspected early-onset sepsis. The prevalence of culture-proven early-onset sepsis is 0·1% or less in high-income countries, suggesting substantial overtreatment. We assess whether procalcitonin-guided decision making for suspected early-onset sepsis can safely reduce the duration of antibiotic treatment.

METHODS

We did this randomised controlled intervention trial in Dutch (n=11), Swiss (n=4), Canadian (n=2), and Czech (n=1) hospitals. Neonates of gestational age 34 weeks or older, with suspected early-onset sepsis requiring antibiotic treatment were stratified into four risk categories by their treating physicians and randomly assigned [1:1] using a computer-generated list stratified per centre to procalcitonin-guided decision making or standard care-based antibiotic treatment. Neonates who underwent surgery within the first week of life or had major congenital malformations that would have required hospital admission were excluded. Only principal investigators were masked for group assignment. Co-primary outcomes were non-inferiority for re-infection or death in the first month of life (margin 2·0%) and superiority for duration of antibiotic therapy. Intention-to-treat and per-protocol analyses were done. This trial was registered with ClinicalTrials.gov, number NCT00854932.

FINDINGS

Between May 21, 2009, and Feb 14, 2015, we screened 2440 neonates with suspected early-onset sepsis. 622 infants were excluded due to lack of parental consent, 93 were ineligible for reasons unknown (68), congenital malformation (22), or surgery in the first week of life (3). 14 neonates were excluded as 100% data monitoring or retrieval was not feasible, and one neonate was excluded because their procalcitonin measurements could not be taken. 1710 neonates were enrolled and randomly assigned to either procalcitonin-guided therapy (n=866) or standard therapy (n=844). 1408 neonates underwent per-protocol analysis (745 in the procalcitonin group and 663 standard group). For the procalcitonin group, the duration of antibiotic therapy was reduced (intention to treat: 55·1 vs 65·0 h, p<0·0001; per protocol: 51·8 vs 64·0 h; p<0·0001). No sepsis-related deaths occurred, and 9 (<1%) of 1710 neonates had possible re-infection. The risk difference for non-inferiority was 0·1% (95% CI -4·6 to 4·8) in the intention-to-treat analysis (5 [0·6%] of 866 neonates in the procalcitonin group vs 4 [0·5%] of 844 neonates in the standard group) and 0·1% (-5·2 to 5·3) in the per-protocol analysis (5 [0·7%] of 745 neonates in the procalcitonin group vs 4 [0·6%] of 663 neonates in the standard group).

INTERPRETATION

Procalcitonin-guided decision making was superior to standard care in reducing antibiotic therapy in neonates with suspected early-onset sepsis. Non-inferiority for re-infection or death could not be shown due to the low occurrence of re-infections and absence of study-related death.

FUNDING

The Thrasher Foundation, the NutsOhra Foundation, the Sophia Foundation for Scientific research.

Biomarkers of necrotizing enterocolitis: a review of literature

Necrotizing enterocolitis (NEC) is among the most serious gastrointestinal emergency in very low birth weight (VLBW), extremely low birth weight (ELBW) and extremely low gestational age neonates (ELGAN), affecting 7-14% of these neonates. Despite extensive research, the underlying aetiology of NEC still remains blurred. Due to high mortality, morbidity and its delayed presentation, early detection of NEC is considered to be lifesaving. A number of biomarkers have been studied for early detection and prediction of severity of NEC but till date, no ideal marker has been discovered. Molecular techniques like proteomic and metabolomic have recently emerged in the field for the development of biomarkers for early detection and understanding the pathophysiology of NEC. We did literature search for identifying all biomarkers that have been used for the detection of NEC and, in this review article, we discuss these biomarkers along with the available current evidence.

Cerebrospinal fluid procalcitonin as a biomarker of bacterial meningitis in neonates

OBJECTIVE

The objective of the study was to study the performance of cerebrospinal fluid (CSF) procalcitonin as a marker for bacterial meningitis in neonates, and to determine its optimal 'cutoff' in CSF that can be called significant for the diagnosis.

STUDY DESIGN

Neonates qualifying for lumbar puncture were prospectively studied. Procalcitonin and established CSF parameters were recorded.

RESULTS

At a cut-off value of 0.33 ng ml^-1, CSF procalcitonin had a sensitivity of 0.92, specificity of 0.87, with positive and negative likelihood ratios of 7.13 and 0.092, respectively. The area under the curve for different CSF parameters was: 0.926 (0.887 to 0.964) (P<0.001) for procalcitonin, 0.965 (0.956 to 0.974) for total leukocyte count, 0.961 (0.94 to 0.983) for neutrophil count, 0.874 (0.825 to 0.923) for protein, 0.946 (0.914 to 0.978) for sugar and 0.92 (0.955 to 0.992) for CSF:serum sugar ratio. The lumbar puncture was traumatic in 36 (21.4%) patients; out of these 15 (41.7%) had bacterial meningitis and 21 (58.3%) had no meningitis. In traumatic lumbar tap group, the median (IQR) CSF procalcitonin in patients with and without meningitis was 1.41 (0.32-3.42) ng/ml and 0.21(0.20-0.31) ng/ml respectively (p<0.05).

CONCLUSIONS

Procalcitonin measurement has diagnostic efficiency similar to the established CSF markers. Routine assessment of procalcitonin in clean non-contaminated CSF may not yield additional information, but it may have clinical utility in situations where diagnosis of meningitis is in dilemma, as in the case of blood contamination of CSF in traumatic lumbar punctures.

Bloodstream Infections

Bacteremia and sepsis are conditions associated with high mortality and are of great impact to health care operations. Among the top causes of mortality in the United States, these conditions cause over 600 fatalities each day. Empiric, broad-spectrum treatment is a common but often a costly approach that may fail to effectively target the correct microbe, may inadvertently harm patients via antimicrobial toxicity or downstream antimicrobial resistance. To meet the diagnostic challenges of bacteremia and sepsis, laboratories must understand the complexity of diagnosing and treating septic patients, in order to focus on creating algorithms that can help direct a more targeted approach to antimicrobial therapy and synergize with existing clinical practices defined in new Surviving Sepsis Guidelines. Significant advances have been made in improving blood culture media; as yet no molecular or antigen-based method has proven superior for the detection of bacteremia in terms of limit of detection. Several methods for rapid molecular identification of pathogens from blood cultures bottles are available and many more are on the diagnostic horizon. Ultimately, early intervention by molecular detection of bacteria and fungi directly from whole blood could provide the most patient benefit and contribute to tailored antibiotic coverage of the patient early on in the course of the disease. Although blood cultures remain as the best means of diagnosing bacteremia and candidemia, complementary testing with antigen tests, microbiologic investigations from other body sites, and histopathology can often aid in the diagnosis of disseminated disease, and application of emerging nucleic acid test methods and other new technology may greatly impact our ability to bacteremic and septic patients, particularly those who are immunocompromised.

New diagnostic biomarker in acute diarrhea due to bacterial infection in children

BACKGROUND AND OBJECTIVES

Diarrhea is a major cause of morbidity and mortality in children, and diarrhea may be due to infection that is bacterial or non-bacterial. Differentiation between diarrhea from a bacterial or non-bacterial infection is not a simple task, and no single method is present to differentiate between these causes of diarrhea.To evaluate the diagnostic accuracy of soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) and procalcitonin (PCT) in the diagnosis of acute diarrhea due to bacterial infection.

PATIENTS AND METHODS

Case control study of forty children with bacterial infection diarrhea diagnosed by stool culture and CRP, 40 children with acute non-bacterial infection diarrhea and 30 age- and sex-matched healthy controls. Stool cultures, serum CRP, PCT and serum sTREM-1 were measured in all children on admission.

RESULTS

Children with acute bacterial infection diarrhea had a significant increase in the serum sTREM-1 and PCT levels on admission compared to patients with nonbacterial infection diarrhea and controls (26.3667 ± 16.8184 ng/ml vs 7.2267 ± 6.4174 ng/ml vs 6.7367 ± 5.6479 ng/ml and 39.9933 ± 22.5260 ng/ml vs 1.8533 ± 1.7123 vs 0.2840 ± 0.1208 ng/ml, respectively; P < 0.05). sTREM-1 demonstrated significantly higher sensitivity (93.7%) and specificity (94.3%) in the prediction of bacterial infection as a cause of acute diarrhea in children with an area under the receiver operator characteristic (ROC) curve (95% CI) of 0.94 (0.84-0.99) at a cutoff value of 12.4 ng/ml.

CONCLUSIONS

Both serum PCT and sTREM-1 are valuable in the early diagnosis of acute bacterial infection-induced diarrhea in children, and there was markedly higher diagnostic discriminatory power for sTREM-1.

Accuracy of serum procalcitonin for the diagnosis of sepsis in neonates and children with systemic inflammatory syndrome: a meta-analysis

Background

A number of biomarkers have been studied for the diagnosis of sepsis in paediatrics, but no gold standard has been identified. Procalcitonin (PCT) was demonstrated to be an accurate biomarker for the diagnosis of sepsis in adults and showed to be promising in paediatrics. Our study reviewed the diagnostic accuracy of PCT as an early biomarker of sepsis in neonates and children with suspected sepsis.

Methods

A comprehensive literature search was carried out in Medline/Pubmed, Embase, ISI Web of Science, CINAHL and Cochrane Library, for studies assessing PCT accuracy in the diagnosis of sepsis in children and neonates with suspected sepsis. Studies in which the presence of infection had been confirmed microbiologically or classified as “probable” by chart review were included. Studies comparing patients to healthy subjects were excluded. We analysed data on neonates and children separately.

Our primary outcome was the diagnostic accuracy of PCT at the cut-off of 2-2.5 ng/ml, while as secondary outcomes we analysed PCT cut-offs <2 ng/ml and >2.5 ng/ml. Pooled sensitivities and specificities were calculated by a bivariate meta-analysis and heterogeneity was graphically evaluated.

Results

We included 17 studies, with a total of 1408 patients (1086 neonates and 322 children). Studies on neonates with early onset sepsis (EOS) and late onset sepsis (LOS) were grouped together. In the neonatal group, we calculated a sensitivity of 0.85, confidence interval (CI) (0.76; 0.90) and specificity of 0.54, CI (0.38; 0.70) at the PCT cut-off of 2.0-2.5 ng/ml. In the paediatric group it was not possible to undertake a pooled analysis at the PCT cut-off of 2.0-2.5 ng/ml, due to the paucity of the studies.

Conclusions

PCT shows a moderate accuracy for the diagnosis of sepsis in neonates with suspected sepsis at the cut-off of 2.0-2.5 ng/ml. More studies with high methodological quality are warranted, particularly in neonates, studies considering EOS and LOS separately are needed to improve specificity.

Trial registration

PROSPERO Identifier: CRD42016033809. Registered 30 Jan 2016.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2396-7) contains supplementary material, which is available to authorized users.

Biomarkers for the diagnosis of neonatal sepsis and necrotizing enterocolitis: Clinical practice guidelines

Sepsis and necrotizing enterocolitis are major contributors to morbidity and mortality in neonates, especially in those born preterm. While therapeutic interventions are available for both (for e.g. antibiotics), a major dilemma is early diagnosis so that these interventions can be done in a timely manner. As clinical evaluation alone is unreliable in identifying infants in the early stages of neonatal sepsis or necrotizing enterocolitis, there is a need to find specific biomarkers associated with these conditions to improve diagnostic capabilities. Optimal use of biomarkers in the identification and management of affected neonates requires an understanding of the properties of each marker within the timeline of the inflammatory response. We propose that early- and mid-phase markers such as neutrophil CD64 and procalcitonin should be combined with the late-phase biomarker C-reactive protein for maximal diagnostic benefit. Appropriately powered trials evaluating the serial measurements of these markers in decisions related to antibiotic stewardship in the neonatal population are indicated, in addition to more studies investigating other potentially useful biomarkers.

Utility of cytokine, adhesion molecule and acute phase proteins in early diagnosis of neonatal sepsis

Background and Aim:

Neonatal infection, including bacterial sepsis, is a major health care issue with an annual global mortality in excess of one million lives. Therefore, this study aimed to evaluate the potential diagnostic value of C-reactive protein (CRP), E-selectin, procalcitonin (PCT), interleukins-6 (IL-6), and tumor necrosis factor-α (TNF-α) both independently and in combination for the diagnosis of neonatal sepsis in its earliest stages.

Materials and Methods:

A total of 320 subjects were included in this study. A prospective cross-sectional study was conducted among neonates admitted to Neonatal Intensive Care Unit at King Abdulaziz Medical City, Riyadh, KSA during January 2013 to August 2015, the study based on three study groups categorized according to clinical symptoms and blood culture result. Study groups include healthy control neonates (n = 80), clinical sepsis (CS) group (n = 80) with clinical signs of sepsis but their blood culture was negative, and sepsis group with clinical signs of sepsis and their blood culture was positive.

Results:

The study observed significant difference in plasma levels of CRP, IL-6, TNF-α, E-selectin, and PCT in patients group when compared with control group (P < 0.001). Furthermore, the levels are significantly different between patient groups including CS and neonatal sepsis group. Moreover, result observed significant difference in CRP and IL-6 in early onset sepsis (EOS) when compared with late onset sepsis (LOS) neonates (P < 0.001 and 0.01), respectively, while there were no significant difference in TNF-α, E-selectin, and PCT between EOS and LOS (P = 0.44, 0.27 and 0.24), respectively. Regarding biomarkers accuracy, the result showed that CRP has the best diagnostic accuracy with cutoff value of 3.6 ng/ml (sensitivity 78% and specificity of 70%). The best combination is shown with CRP and IL-6 in which sensitivity increased to 89% and specificity to 79%.

Conclusion:

It was concluded that infected new-born babies have a higher E-selectin, PCT, IL-6, TNF-α, and CRP compared with the neonates with CS and control. IL-6, TNF-α, and CRP should be measured in combination for mare diagnostic accuracy in neonatal sepsis. Likewise, PCT should be investigated as a part of sepsis screening for all suspected neonates.

Serum Procalcitonin Level Reflects the Severity of Cellulitis

Background

Cellulitis is a common bacterial infection of the superficial skin. Procalcitonin is one of the precursor proteins of calcitonin, its levels are elevated in bacterial infection, and it has been established as a diagnostic marker for severe bacterial infections.

Objective

This study evaluated the clinical usefulness of procalcitonin for predicting disease severity and prognosis of cellulitis.

Methods

We reviewed the medical records of 160 patients diagnosed with cellulitis in the past 3 years. Body temperature, procalcitonin, white blood cell (WBC), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels were measured on their first day of admission. The associations of procalcitonin, WBC, ESR, and CRP with the body temperature and the number of hospitalized days were assessed.

Results

Procalcitonin, WBC, and CRP showed a positive correlation with body temperature. In addition, procalcitonin, WBC, ESR, and CRP showed a positive correlation with number of hospitalized days (p<0.05).

Conclusion

In patients diagnosed with cellulitis, proclacitonin was a helpful parameter to indicate the severity of disease and also a useful predictor of prognosis.

Diagnosis and Treatment of Central Nervous System Infections in the Emergency Department

Central nervous system (CNS) infections, including meningitis, encephalitis, and brain abscess, are rare but time-sensitive emergency department (ED) diagnoses. Patients with CNS infection can present to the ED with nonspecific signs and symptoms, including headache, fever, altered mental status, and behavioral changes. Neuroimaging and CSF fluid analysis can appear benign early in the course of disease. Delaying therapy negatively impacts outcomes, particularly with bacterial meningitis and herpes simplex virus encephalitis. Therefore, diagnosis of CNS infection requires vigilance and a high index of suspicion based on the history and physical examination, which must be confirmed with appropriate imaging and laboratory evaluation.

Early prediction of renal parenchymal injury with serum procalcitonin

INTRODUCTION

Urinary tract infection (UTI) is one of the most common bacterial infections in children that can be associated with renal parenchymal injuries and late scars. Dimercaptosuccinic acid (DMSA) renal scan is known as golden standard for detecting acute pyelonephritis (APN) that has a lot of difficulties and limitations.

OBJECTIVES

we designed this study the accuracy of one inflammatory marker, serum procalcitonin (PCT) to identify as an early predictor of renal injuries.

PATIENTS AND METHODS

A prospective study was carried out in 95 patients who admitted in the hospital with the first febrile UTI. Serum PCT of all patients was measured; sensitivity, specificity, positive and negative predictive value (PPV and NPV) of this marker was analyzed compared to DMSA scan. P value <0.05 was taken as significant.

RESULTS

In total, 79 females and 16 males were investigated. There are 42 cases in group 1 with normal DMSA scan and 53 patients in group two with renal parenchymal injuries in their scans. Mann-Whitney test showed a meaningful relation between the two groups regarding PCT level (P<0.0001). Sensitivity, specificity, PPV and NPV of PCT reported in optimum cut off were 70%, 88.1%, 88.1% and 70%, respectively. The positive likelihood ratio (PLR) of PCT test was 5.8.

CONCLUSION

In the current survey, PCT was the eligible inflammatory marker to predict renal parenchymal injuries in children with proper sensitivity, specificity, PPV and NPV that play also a pivotal role in the children aged less than 24 months, although, more studies should be undertaken to confirm.

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.

Procalcitonina como marcador de sepsis en niños

<p>Introducción. La procalcitonina es un biomarcador de infección bacteriana severa y sepsis, con aplicación diagnóstica, para severidad y pronóstico, el cual muestra valores de sensibilidad, especificidad y puntos de corte variables en niños. Materiales y métodos. Estudio retrospectivo, observacional y descriptivo. Se incluyeron niños de 7 días a 18 años, a quienes se les tomó procalcitonina y cultivo el mismo día. Se evaluaron otros biomarcadores como proteína C reactiva y los datos se tomaron de la historia clínica por medio de un formulario. Resultados. Se incluyeron 274 muestras de procalcitonina y cultivos, correspondientes a 162 pacientes con edad promedio de 1.5 años —59% masculinos—. De los 274 cultivos, el 81% fueron hemocultivos, siendo positivos el 17%. La procalcitonina con punto de corte >0.5ng/ml mostró sensibilidad de 76%, especificidad de 46%, VPP de 23% y VPN de 90% para sepsis, con AUC 0.6899 (IC95%: 0.6059-0.774). Se encontró de forma estadísticamente significativa que a mayor valor de procalcitonina mayor mortalidad (p=0.003). La procalcitonina mostró mejor rendimiento que los otros biomarcadores para predecir sepsis. Conclusión. La procalcitonina tiene un buen rendimiento diagnóstico como marcador de sepsis en niños —con mayor utilidad cuando toma valores negativos— y buen valor pronóstico al relacionarse con mortalidad.</p>

Procalcitonin as a Serum Biomarker for Differentiation of Bacterial Meningitis From Viral Meningitis in Children: Evidence From a Meta-Analysis

Several studies have explored the use of serum procalcitonin (PCT) in differentiating between bacterial and viral etiologies in children with suspected meningitis. We pooled these studies into a meta-analysis to determine the PCT diagnostic accuracy. All major databases were searched through March 2015. No date or language restrictions were applied. Eight studies (n = 616 pediatric patients) were included. Serum PCT assay was found to be very accurate for differentiating the etiology of pediatric meningitis with pooled sensitivity and specificity of 0.96 (95% CI = 0.92-0.98) and 0.89 (95% CI = 0.86-0.92), respectively. The pooled positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio (DOR), and area under the curve (AUC) for PCT were 7.5 (95% CI = 5.6-10.1), 0.08(95% CI = 0.04-0.14), 142.3 (95% CI = 59.5-340.4), and 0.97 (SE = 0.01), respectively. In 6 studies, PCT was found to be superior than CRP, whose DOR was only 16.7 (95%CI = 8.8-31.7). Our meta-analysis demonstrates that serum PCT assay is a highly accurate and powerful test for rapidly differentiating between bacterial and viral meningitis in children.

A new sensitive automated assay for procalcitonin detection: LIAISON® BRAHMS PCT® II GEN

Objectives

To assess the performance of LIAISON^® BRAHMS PCT^® II GEN (DiaSorin, Saluggia, Italy) in procalcitonin (PCT) determination by comparing it to the assay reference method B·R·A·H·M·S PCT KRYPTOR (Thermo Fisher Scientific Clinical Diagnostics, Hennigsdorf, Germany) and assessing its ability to discriminate between healthy subjects and patients with suspected infection.

Methods

Diagnostic performance was evaluated on: a) 193 selected samples covering the assay range, whose procalcitonin levels were already evaluated with the B·R·A·H·M·S PCT^® KRYPTOR; b) prospective samples: 150 apparently healthy specimens obtained from a blood bank, 161 hospitalized patients (not with specific pathologies), 243 apparently healthy children.

Results

The comparison of LIAISON^® BRAHMS PCT^® II GEN to the reference method B·R·A·H·M·S PCT KRYPTOR yielded high correlation coefficients: slope of Deming fit equal to 1.04 (95% CI: 0.99–1.09) with an intercept equal to 0.05 (95% CI: −0.09 to 0.19) and a high concordance (98.4% (95% CI: 95.5–99.7%)) at the 0.5 ng/mL cut-off. Moreover, the results obtained using prospective samples showed: (i) no samples with PCT concentration >0.5 ng/mL (cut-off) for the apparently healthy adults (highest value=0.033 ng/mL, 95th percentile and 97.5th percentile <0.02 ng/mL); (ii) 2 samples >0.5 ng/mL for hospitalized patients (highest value=0.715 ng/mL, 95th percentile: 0.054 ng/mL; 97.5th percentile: 0.088 ng/mL); (iii) 3 samples >0.5 ng/mL for the healthy children population (highest value=0.713 ng/mL, 95th percentile: 0.155 ng/mL; 97.5th percentile: 0.275 ng/mL).

Conclusion

The fully automated LIAISON^® BRAHMS PCT^® II GEN agrees well with the reference method and is suitable for early diagnosis of sepsis, severe bacterial infection and guiding antibiotic therapy.

Usefulness of analytical parameters in the management of paediatric patients with suspicion of acute pyelonephritis. Is procalcitonin reliable?

OBJECTIVE

To investigate the usefulness of procalcitonin (PCT) and other analytical parameters (white blood cell count [WBC], C-reactive protein [CRP]) as markers of acute renal damage in children after a first febrile or afebrile urinary tract infection (UTI).

METHODS

A retrospective study was conducted on children with a first episode of UTI admitted between January 2009 to December 2011, and in whom serum PCT, CRP and white blood cell count were measured, as well as assessing the acute renal damage with renal scintigraphy with ^99mTc-DMSA (DMSA) within the first 72h after referral. A descriptive study was performed and ROC curves were plotted, with optimal cut-off points calculated for each parameter.

RESULTS

The 101 enrolled patients were divided into two groups according to DMSA scintigraphy results, with 64 patients being classified with acute pyelonephritis (APN), and 37 with UTI. The mean WBC, CRP and PCT values were significantly higher in patients with APN with respect to normal acute DMSA. The area under the ROC curve was 0.862 for PCR, 0.774 for WBC, and 0.731 for PCT. The optimum statistical cut-off value for PCT was 0.285ng/ml (sensitivity 71.4% and specificity 75%).

CONCLUSION

Although the mean levels of fever, WBC, CRP, and PCT were significantly increased in patients with APN than in those who had UTI, the sensitivity and specificity of these analytical parameters are unable to predict the existence of acute renal damage, making the contribution by renal DMSA scintigraphy essential.

Recognising early onset neonatal sepsis: an essential step in appropriate antimicrobial use

Early diagnosis and timely treatment of early onset neonatal sepsis (EOS) are essential to prevent life threatening complications. Subtle, nonspecific clinical presentation and low predictive values of biomarkers complicate early diagnosis. This uncertainty commonly results in unnecessary and prolonged empiric antibiotic treatment. Annually, approximately 395,000 neonates (7.9% of live term births) are treated for suspected EOS in the European Union, while the incidence of proven EOS varies between 0.01 and 0.53 per 1000 live births. Adherence to guidelines for the management of suspicion of EOS is poor. Pragmatic approaches to minimise overtreatment in neonates with suspected EOS, using combined stratified risk algorithms, based on maternal and perinatal risk factors, clinical characteristics of the neonate and sequential biomarkers are promising.

Procalcitonin as a Diagnostic and Prognostic Factor for Tuberculosis Meningitis

Background and Purpose

We investigated the potential role of serum procalcitonin in differentiating tuberculosis meningitis from bacterial and viral meningitis, and in predicting the prognosis of tuberculosis meningitis.

Methods

This was a retrospective study of 26 patients with tuberculosis meningitis. In addition, 70 patients with bacterial meningitis and 49 patients with viral meningitis were included as the disease control groups for comparison. The serum procalcitonin level was measured in all patients at admission. Differences in demographic and laboratory data, including the procalcitonin level, were analyzed among the three groups. In addition, we analyzed the predictive factors for a prognosis of tuberculosis meningitis using the Glasgow Coma Scale (GCS) at discharge, and the correlation between the level of procalcitonin and the GCS score at discharge.

Results

Multiple logistic regression analysis showed that a low level of procalcitonin (≤1.27 ng/mL) independently distinguished tuberculosis meningitis from bacterial meningitis. The sensitivity and specificity for distinguishing tuberculosis meningitis from bacterial meningitis were 96.2% and 62.9%, respectively. However, the level of procalcitonin in patients with tuberculosis meningitis did not differ significantly from that in patients with viral meningitis. In patients with tuberculosis meningitis, a high level of procalcitonin (>0.4 ng/mL) was a predictor of a poor prognosis, and the level of procalcitonin was negatively correlated with the GCS score at discharge (r=-0.437, p=0.026).

Conclusions

We found that serum procalcitonin is a useful marker for differentiating tuberculosis meningitis from bacterial meningitis and is also valuable for predicting the prognosis of tuberculosis meningitis.

Discrepancies between plasma procalcitonin and C-reactive protein levels are common in acute illness

AIM

Procalcitonin (PCT) and C-reactive protein (CRP) are biomarkers of bacterial infection with distinct clinical qualities. This study aimed to determine the occurrence and significance of discrepancies in plasma PCT and CRP levels in hospitalised children.

METHODS

This was a single centre, retrospective analysis of simultaneous PCT and CRP measurements. Clinical characteristics, microbiological findings and diagnoses were compared between cases in which only PCT or CRP levels were elevated.

RESULTS

We studied 635 pairs of PCT and CRP measurements and found discrepancies in 29% of these. In the group with increased PCT and low CRP, there were more children with hypoxia or haemodynamic stress (14 versus 0, p < 0.001) and more bacteraemic patients (eight versus zero, p = 0.001) than in the group with low PCT and increased CRP. The latter group was associated with focal bacterial infections (three versus 18, p = 0.009), inflammatory conditions (one versus 12, p = 0.016) and postoperative setting (one versus 19, p = 0.001). Diabetic ketoacidosis was associated with a marked elevation of PCT.

CONCLUSION

Discrepancies in plasma PCT and CRP levels occurred in 29% of acutely ill children. Both biomarkers can increase in the absence of bacterial infection, but PCT may offer an advantage over CRP in the diagnosis of bacteraemia.

Relationship Between Serum Albumin Levels and Infections in Newborn Late Preterm Infants

Background

We aimed to evaluate the clinical value of serum albumin levels for the evaluation and prognosis of late preterm infants with infections.

Material/Methods

This was a retrospective study performed in late preterm infants admitted at the neonatal intensive care unit (NICU) of the Liaocheng People’s Hospital between July 2012 and March 2013. Data, including laboratory test results, neonatal critical illness score (NCIS), perinatal complications and prognosis, were analyzed. The newborn infants were divided into 3 groups according to their serum albumin levels, (≥30 g/L, 25–30 g/L and ≤25 g/L for high, moderate, and low, respectively).

Results

Among 257 patients, birth weight was 2003±348 g, gestational age was 35.7±2.3 weeks, and 59.1% were male. In addition, 127 (49.4%) were in the low albumin group. There were 32 patients with sepsis, 190 with infections, and 35 without infection, and their rates of hypoalbuminemia were 86.0%, 50.5%, and 30.7%, respectively (P<0.05). Albumin levels of the patients who survived were higher than those of the patients who died. In the low albumin group, the number of individual-event-critical NCIS cases and the frequency of multiple organs injuries were 63.8% and 28.3%, respectively, and were higher than in the 2 other groups. Mortality was higher in patients with sepsis. Hypoalbuminemia was associated with severe adverse outcomes (odds ratio=6.3, 95% confidence interval: 3.7–10.9, P<0.001).

Conclusions

Hypoalbuminemia was frequent among neonates with sepsis. Lower albumin levels might be associated with a poorer prognosis. Albumin levels could be appropriate for the diagnosis and prognosis of late preterm neonates with infections.

Monocyte HLA-DR expression and neutrophil CD64 expression as biomarkers of infection in critically ill neonates and infants

BACKGROUND

Reduced monocyte HLA-DR expression and increased neutrophil CD64 expression have been proposed as biomarkers of infection.

METHODS

From 2009-2011, blood samples from neonatal intensive care unit (NICU) and pediatric intensive care unit (ICU) patients <1 y of age were collected at enrollment and during subsequent evaluation for suspected infection, if it occurred. Samples were analyzed for monocyte HLA-DR and neutrophil CD64 expression levels by flow cytometry.

RESULTS

Forty-seven infants had study samples collected at enrollment; 26 infants had study samples collected at the time of a suspected infection. At enrollment, there was an inverse relationship between neutrophil CD64 expression and age (P ≤ 0.047). At the time of suspected infection, infants with an infection demonstrated a lower percentage of HLA-DR+ monocytes (P = 0.02, area under the curve (AUC) 0.78), higher percentage of CD64+ neutrophils (P = 0.009, AUC 0.81), and higher neutrophil CD64 expression levels (P = 0.04, AUC 0.75).

CONCLUSION

Monocyte HLA-DR and neutrophil CD64 expression in critically ill infants are related to age and infection.

Normal values for pancreatic stone protein in different age groups

Background

Pancreatic stone protein (PSP) has been identified as a promising sepsis marker in adults, children and neonates. However, data on population-based reference values are lacking. This study aimed to establish age-specific reference values for PSP.

Methods

PSP was determined using a specific ELISA. PSP serum concentrations were determined in 372 healthy subjects including 217 neonates, 94 infants and children up to 16 years, and 61 adults. The adjacent categories method was used to determine which age categories had significantly different PSP concentrations.

Results

PSP circulating levels were not gender-dependent and ranged from 1.0 to 99.4 ng/ml with a median of 9.2 ng/ml. PSP increased significantly between the age categories, from a median of 2.6 ng/ml in very preterm newborns, to 6.3 ng/ml in term newborns, to 16.1 ng/ml in older children (p < 0.001). PSP levels were higher on postnatal day three compared to levels measured immediately post delivery (p < 0.001). Paired umbilical artery and umbilical vein samples were strongly correlated (p < 0.001). Simultaneously obtained capillary heel-prick versus venous samples showed a good level of agreement for PSP (Rho 0.89, bias 19 %).

Conclusions

This study provides age-specific normal values that may be used to define cut-offs for future trials on PSP. We demonstrate an age-dependent increase of PSP from birth to childhood.

Which Variables Are Useful for Predicting Severe Infection in Children With Febrile Neutropenia?

To distinguish children with chemotherapy-induced febrile neutropenia (FN) at low risk of severe infection, the variables that are significant risk factors must be identified. Our objective was to identify them by applying evidence-based standards. This retrospective 2-center cohort study included all episodes of chemotherapy-induced FN in children in 2005 and 2006. The medical history, clinical, and laboratory data available at admission were collected. Severe infection was defined by bacteremia, a positive culture of a normally sterile body fluid, invasive fungal infection, or localized infection at high risk of extension. Univariate analysis identified potential predictive variables. A generalized mixed model was used to determine the adjusted variables that predict severe infection. We analyzed 372 FN episodes. Severe infections occurred in 16.1% of them. Variables predictive of severe infection at admission were: disease with high risk of prolonged neutropenia (adjusted odds ratio [aOR]=2.5), blood cancer (aOR=1.9), fever ≥38.5°C (aOR=3.7), and C-reactive protein level ≥90 mg/L (aOR=4.5). Now that we have identified these variables significantly associated with the risk of severe infection, they must be validated prospectively before combining the best predictive variables in a decision rule that can be used to distinguish children at low risk.

Procalcitonin and community-acquired pneumonia (CAP) in children

The role of procalcitonin (PCT) as a biomarker for sepsis in adults is well documented, while its role in infections affecting neonatal children remains controversial. Among these infections, Community-Acquired pneumonia (CAP) has been studied extensively, because it's the second cause of death in children in developing countries, and one of the most frequent causes of hospitalization in industrialized countries. The PubMed database and the Cochrane Library were used to search for the following keywords: CAP, procalcitonin, and children. Thirteen articles were studied to determine the role of PCT in CAP management, specifically its usefulness for distinguishing pneumococcal infections from viral and unknown infections, for predicting severity and the correct antibiotic treatment. This paper focuses on the studies performed to identify the best inflammatory biomarker for CAP management. Although there is an increase in studies confirming the usefulness of PCT in CAP management in children, further studies are needed to have better understanding of its role for pediatric CAP management.

Utility of serum procalcitonin and C-reactive protein in severity assessment of community-acquired pneumonia in children

OBJECTIVES

Although the importance of serum Procalcitonin (PCT) levels at diagnosis is well established in adult Community-Acquired Pneumonia (CAP), its use remains controversial in pediatric CAP. The aim of our study is to investigate the role of PCT and C-Reactive Protein (CRP) in the assessment of pediatric CAP severity defined by the extent of consolidation on chest X-rays and the presence of pleural effusion. In this particular setting, no clinical severity score is available at present and chest X-ray, although important for diagnosis confirmation, is not recommended as routine test.

DESIGN AND METHODS

The study involved 119 children admitted to the Department of Pediatric Infectious Disease for radiographically documented CAP aged 1 year to 14 years, without chronic diseases. Baseline PCT, CRP and routine laboratory tests were performed on admission.

RESULTS

The median PCT (μg/L) and CRP (mg/L) were 0.11 (0.05–0.58) and 21.3 (4.2–48.1), respectively. PCT showed a good correlation with CRP, neutrophils and WBC (r = 0.538, P < 0.001; r = 0.377, P < 0.001; r = 0.285, P0.002, respectively). CRP, but not PCT, was associated with lobar consolidation (P = 0.007) and pleural effusion (P = 0.002). Logistic regression analysis revealed that only CRP was a predictor of lobar consolidation (OR: 1.078; 95% CI: 1.017–1.143; P = 0.011) and pleural effusion (OR: 1.076; 95% CI: 1.005–1.153; P = 0.036).

CONCLUSION

Our findings revealed that PCT is correlated to the main inflammatory markers in children with CAP. CRP, unlike PCT, is able to predict the extent of chest X-ray infiltration and ultimately the severity of the disease confirming its usefulness in the management of pneumonia

Procalcitonin levels in patients with positive blood culture, positive body fluid culture, sepsis, and severe sepsis: a cross-sectional study

BACKGROUND

Numerous investigations on procalcitonin (PCT) have been carried out, although few with large sample size. To deal with the complexity of sepsis, an understanding of PCT in heterogeneous clinical conditions is required.

METHODS

Hospitalized patients aged 10-79 years were included in this retrospective and cross-sectional study. PCT tests were assayed within 2 days of blood culture.

RESULTS

A total of 2952 cases (from 2538 patients) were enrolled in this study, including 440 cases in the 'positive BC' group, 123 cases in the 'positive body fluid culture' group, and 2389 cases in the 'negative all culture' group. Median PCT values were 4.53 ng/ml, 2.95 ng/ml, and 0.49 ng/ml, respectively. Median PCT values in the gram-negative BC group and gram-positive BC group, respectively, were 6.99 ng/ml and 2.96 ng/ml. Median PCT values in the 'positive hydrothorax culture' group, 'positive ascites culture' group, 'positive bile culture' group, and 'positive cerebrospinal fluid culture' group, respectively, were 1.39 ng/ml, 8.32 ng/ml, 5.98 ng/ml, and 0.46 ng/ml. In all, 357 cases were classified into the 'sepsis' group, 150 of them were classified into the 'severe sepsis' group. Median PCT values were 5.63 ng/ml and 11.06 ng/ml, respectively.

CONCLUSIONS

PCT could be used in clinical algorithms to diagnose positive infections and sepsis. Different PCT levels could be related to different kinds of microbemia, different infection sites, and differing severity of sepsis.