Reliability of procalcitonin in neonatology. Experience in 59 preterm newborns

Serum Biomarkers for the Early Detection of the Early-Onset Neonatal Sepsis: A Single-Center Prospective Study

BACKGROUND

Reducing the hazards of the early-onset neonatal sepsis (EONS) is a priority justifying the further investigation for potential biomarkers for its early diagnosis.

PURPOSE

We aimed to investigate the diagnostic value of presepsin, procalcitonin, lactoferrin, interleukin (IL)-6, and IL-8 for the early diagnosis of EONS.

METHODS

A prospective comparative study, including 30 cases with highly suspected EONS and 30 matched controls, was conducted. Besides the complete blood count and blood culture, C-reactive protein, procalcitonin, presepsin, IL-6, IL-8, and lactoferrin were measured at the admission and after 72 hours.

RESULTS

At the time of the admission, presepsin, procalcitonin, C-reactive protein, and IL-8 were significantly higher in the sepsis group. The levels of presepsin, procalcitonin, and IL-8 significantly decreased after 72 hours of the admission. Presepsin, procalcitonin, IL-8, and IL-6 showed a high diagnostic ability for sepsis at admission with area under the curve of 0.934, 0.798, 0.775, and 0.751, respectively. The cutoff values of presepsin, procalcitonin, IL-8, and IL-6 were 821 pg/mL, 2.3 ng/mL, 54 pg/mL, and 24 pg/mL, with a sensitivity of 88.9%, 72.2%, 83.3%, and 94.4% and specificity of 85.7%, 80.9%, 71.4%, and 52.4%, respectively. Lactoferrin had the lowest diagnostic ability with area under the curve of 0.558.

IMPLICATIONS FOR PRACTICE

Presepsin was the most accurate biomarker followed by procalcitonin, IL-8, and IL-6 regarding the early diagnosis and management of EONS. The combination between these biomarkers is highly recommended.

IMPLICATIONS FOR RESEARCH

Further studies are needed to investigate the diagnostic ability of the combination of these biomarkers.

Presepsin as a predictor of positive blood culture in suspected neonatal sepsis

BACKGROUND

Although the incidence of neonatal sepsis is decreasing, neonatal sepsis remains a severe life-threatening disease. No current biochemical marker can provide perfect diagnostic accuracy for neonatal sepsis. The aim of this study was therefore to evaluate the accuracy of presepsin (P-SEP) as a novel biomarker of bacterial infection for neonatal sepsis diagnosis.

METHODS

We prospectively studied newborns with sepsis (sepsis group; n = 13) during the first 30 days after birth and compared them with control preterm newborns (control group; n = 18). In addition, we evaluated term newborns with some clinical signs of early onset sepsis (non-sepsis term group; n = 35).

RESULTS

P-SEP in the sepsis group was significantly higher than in the control group (P < 0.001) The area under the curve for P-SEP was 0.868 (95%CI: 0.71-1.00). A P-SEP cut-off of 795 pg/mL was established, with 85% sensitivity and 89% specificity. The positive and negative predictive values were 85% and 89%, respectively. In the non-sepsis term group, P-SEP had better stability than white blood cells and C-reactive protein for 3 days after birth.

CONCLUSIONS

P-SEP can better discriminate between infections and non-infectious inflammatory conditions than the currently used biomarkers.

Early-Onset Neonatal Sepsis: Still Room for Improvement in Procalcitonin Diagnostic Accuracy Studies

To perform a systematic review assessing accuracy and completeness of diagnostic studies of procalcitonin (PCT) for early-onset neonatal sepsis (EONS) using the Standards for Reporting of Diagnostic Accuracy (STARD) initiative.EONS, diagnosed during the first 3 days of life, remains a common and serious problem. Increased PCT is a potentially useful diagnostic marker of EONS, but reports in the literature are contradictory. There are several possible explanations for the divergent results including the quality of studies reporting the clinical usefulness of PCT in ruling in or ruling out EONS.We systematically reviewed PubMed, Scopus, and the Cochrane Library databases up to October 1, 2014. Studies were eligible for inclusion in our review if they provided measures of PCT accuracy for diagnosing EONS. A data extraction form based on the STARD checklist and adapted for neonates with EONS was used to appraise the quality of the reporting of included studies.We found 18 articles (1998-2014) fulfilling our eligibility criteria which were included in the final analysis. Overall, the results of our analysis showed that the quality of studies reporting diagnostic accuracy of PCT for EONS was suboptimal leaving ample room for improvement. Information on key elements of design, analysis, and interpretation of test accuracy were frequently missing.Authors should be aware of the STARD criteria before starting a study in this field. We welcome stricter adherence to this guideline. Well-reported studies with appropriate designs will provide more reliable information to guide decisions on the use and interpretations of PCT test results in the management of neonates with EONS.

[Diagnostic value of suspicion criteria for early-onset neonatal bacterial infection: report ten years after the Anaes recommendations]

BACKGROUND

Because clinical symptoms and biological markers are neither sensitive nor specific, newborns are frequently suspected of having an infection. In France, 30-50% of newborns are suspected of having early-onset sepsis (EOS) and many of them undergo laboratory tests and empirical antibiotic treatments while awaiting results. The aim of this study was to evaluate the diagnostic value of various suspicion criteria for EOS as recommended by the Anaes since 2002, and the value of umbilical cord blood procalcitonin (PCT), currently assayed in our maternity ward.

MATERIAL AND METHODS

This 4-year retrospective study in the CHU of Nantes included hospitalized newborns with suspected early neonatal infection. Infection status was established according to the Anaes definitions and clinical evolution.

RESULTS

The study included 2151 newborns. Among anamnestic criteria, only prematurity significantly increased the risk of EOS (relative risk of 3.1; 95% CI 1.4-7.0). The relative risk of infection for a symptomatic newborn was 12.2 (95% CI 4.9-30.2; P<0.0001). Laboratory test results were the most predictive criteria. The relative risk to be infected was 291.6 (95% CI 70.7-1,214.0; P<0.0001) with a blood cord PCT value>0.6 ng/L. The positive post-test probability was 28% (95% CI: 23-33) and the negative post-test probability was close to 0 (95% CI: 0-0).

CONCLUSION

Clinical criteria of postnatal life adaptation are more predictive of early-onset neonatal infection than anamnestic criteria are. The blood cord PCT value could be a helpful marker in the identification of infected newborns. PCT measured in umbilical cord blood could be included in a general algorithm in order to identify as soon as possible newborns with a high risk of EOS.

The importance of biomarkers in neonatology

Despite a 35% decline in the mortality rate for infants aged <5 years over the past two decades, every year nearly 40% of all deaths in this age group occur in the neonatal period, defined as the first 28 days of life. New knowledge on molecular and biochemical pathways in neonatal diseases will lead to the discovery of new candidate biomarkers potentially useful in clinical practice. In the era of personalized medicine, biomarkers may play a strategic role in accelerating the decline in neonatal mortality by assessing the risk of developing neonatal diseases, by implementing tailored therapeutic treatment, and by predicting the clinical outcome. However, there is an urgent need to reduce the gap in translating newly acquired knowledge from bench to bedside. Traditional and candidate biomarkers for neonatal sepsis and necrotizing enterocolitis will be discussed in this review, such as C-reactive protein (CRP), procalcitonin (PCT), serum amyloid A (SAA), soluble form of CD14 subtype presepsin (sCD14-ST), lipolysaccharide binding protein (LBP), angiopoietins (Ang)-1 and -2, soluble form of triggering receptor expressed on myeloid cells (sTREM-1), soluble form of urokinase-type plasminogen activator receptor (suPAR), platelet-activating factor (PAF) and calprotectin. New frontiers in managing critically ill newborns may be opened by metabolomics, a diagnostic tool based on the recognition of metabolites contained in biological fluids. Metabolomics represents the passage from a descriptive science to a predictive science, having the potential to translate benchtop research to real clinical benefits.

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.

Biomarkers for diagnosis of neonatal infections: A systematic analysis of their potential as a point-of-care diagnostics

BACKGROUND

Neonatal infections annually claim lives of 1.4 million neonates worldwide. Until now, there is no ideal diagnostic test for detecting sepsis and thus management of possible sepsis cases often depends on clinical algorithm leading to empirical treatment. This often results in unnecessary antibiotic use, which may lead to emergence of antibiotic resistance. Biomarkers have shown great promise in diagnosis of sepsis and guiding appropriate treatment of neonates. In this study, we conducted a literature review of existing biomarkers to analyze their status for use as a point-of-care diagnostic in developing countries.

METHODS

PubMed and EMBASE database were searched with keywords, 'infections', 'neonates', and 'biomarkers' to retrieve potentially relevant papers from the period 1980 to 2010. Leading hospitals and manufacturers were communicated to inquire about the cost, laboratory requirements and current standing of biomarkers in clinical use.

RESULTS

The search returned 6407 papers on biomarkers; 65 were selected after applying inclusion and exclusion criteria. Among the studies, C-reactive protein (CRP), procalcitonin (PCT) and interleukin 6 (IL-6) were the most widely studied biomarkers and were considered to be most promising for diagnosing neonatal infections. About 90% of the studies were from developed countries; more than 50% were from Europe.

CONCLUSIONS

Extensive work is being performed to find the diagnostic and prognostic value of biomarkers. However, the methodologies and study design are highly variable. Despite numerous research papers on biomarkers, their use in clinical setting is limited to CRP. The methods for detection of biomarkers are far too advanced to be used at the community level where most of the babies are dying. It is important that a harmonized multi-site study is initiated to find a battery of biomarkers for diagnosis of neonatal infections.

Urinary tract infection in the newborn and the infant: state of the art

Urinary tract infection is one of the most common causes of infection in newborns. Obtaining a urinary tract infections (UTIs) diagnosis just on the basis of the clinical findings is frequently difficult, however, being the pediatrician's goal to reduce the risk of renal scarring, a prompt diagnosis and treatment is of extreme importance. The key instrument for the diagnosis of UTIs is represented today by urine culture. However, in reality, the caregivers and investigators are increasingly demanding fast and cheap methods for a rapid and effective diagnosis.