An update on the use of C-reactive protein in early-onset neonatal sepsis: current insights and new tasks

C-reactive protein (CRP) is one of the most studied and most used laboratory tests for neonatal sepsis. As part of the acute-phase reaction to infection, it plays a central role in the humoral response to bacterial invasion. The delayed synthesis during the inflammatory response accounts for its low sensitivity during the early phases of the disease. Diagnostic accuracy clearly improves by the performance of serial determinations and by the combination with earlier markers such as interleukins or procalcitonin. CRP is as well particularly useful for monitoring the response to treatment and guiding antibiotic therapy, though nothing replaces the clinical impression and the gold standard (i.e. culture results). In spite of the large amount of research done on CRP in neonates, some topics are still not fully understood, such as the influence of noninfectious factors on CRP levels in healthy as well as in symptomatic neonates and the role of gestational age and birthweight on CRP kinetics. In this review, we aim to give an update on the current evidence on the use of CRP in neonates.

Fetal and early neonatal interleukin-6 response

In 1998, a systemic fetal cytokine response, defined as a plasma interleukin-6 (IL-6) value above 11 pg/mL, was reported to be a major independent risk factor for the subsequent development of neonatal morbid events even after adjustments for gestational age and other confounders. Since then, the body of literature investigating the use of blood concentrations of IL-6 as a hallmark of the fetal inflammatory response syndrome (FIRS), a diagnostic marker of early-onset neonatal sepsis (EONS) and a risk predictor of white matter injury (WMI), has grown rapidly. In this article, we critically review: IL-6 biological functions; current evidence on the association between IL-6, preterm birth, FIRS and EONS; IL-6 reference intervals and dynamics in the early neonatal period; IL-6 response during the immediate postnatal period and perinatal confounders; accuracy and completeness of IL-6 diagnostic studies for EONS (according to the Standards for Reporting of Diagnostic Accuracy statement); and recent breakthroughs in the association between fetal blood IL-6, EONS, and WMI.

Episodes of hypocarbia and early-onset sepsis are risk factors for cystic periventricular leukomalacia in the preterm infant

BACKGROUND

Septic episodes in preterm infants recently have been reported to be associated with periventricular leukomalacia (PVL). The role of hypocarbia as an independent risk factor for PVL in clinical studies raises many questions without conclusive answers.

AIMS

To evaluate risk factors for cystic PVL focussing on the influence of hypocarbia.

STUDY DESIGN

Retrospective single centre case-control study.

SUBJECTS

Preterm infants 24 to 35 weeks of gestational age and matched (1:2 for gender, birth year, gestational age and birth weight) controls.

OUTCOME MEASURES

Multivariate analysis of perinatal factors being associated with cystic PVL diagnosed by serial ultrasound examinations.

RESULTS

Univariate analysis of risk factors revealed lower 5 and 10 min Apgar scores, and higher rates of neonatal seizures, early-onset sepsis, neonatal steroids, respiratory distress syndrome with surfactant replacement therapy, and episodes of hypocarbia significantly being associated with PVL. Multivariate analysis using a logistic regression model revealed early-onset sepsis and hypocarbia being significantly associated with PVL (p=.022 and .024, respectively). Lowest PaCO(2) values did not differ as did not the duration of hypocarbia, but the onset of hypocarbia was significantly later in PVL cases compared to controls (mean 26 vs. 15 h, p=.033). Neurodevelopmental follow-up at a median time of 46 months was poor showing 88% of the cases having an adverse neurological outcome.

CONCLUSION

We found early-onset sepsis and episodes of hypocarbia within the first days of life being independently associated with PVL.

Amphotericin B transfer to CSF following intravenous administration of liposomal amphotericin B

OBJECTIVES

Although amphotericin B (AmB) and its lipid formulations are used for the treatment of fungal infections of the CNS, the kinetics of AmB in the CSF after intravenous administration of liposomal amphotericin B (LAmB) are not well characterized.

PATIENTS AND METHODS

From 14 paediatric haemato-oncological patients (aged 0.4-19.5 years, median 7.6 years), we obtained 30 CSF samples by means of routine punctures (performed for intrathecal treatment of the underlying diseases) at different timepoints after the prophylactic intravenous infusion of LAmB (AmBisome, 3 mg/kg/day). Concurrent serum samples were obtained to calculate the transfer rates. An HPLC method was used for AmB detection.

RESULTS

CSF levels of AmB 1-100 h after the intravenous infusion of LAmB were between 10 and 120 ng/mL, except in one case with a level of 529 ng/mL. Concurrent serum levels were about 1000-fold higher, ranging between 3 and 75 μg/mL. CSF levels did not show a clear time-dependent concentration profile, but remained at a steady-state for longer than 48 h after infusion. The transfer rate ranged from 0.02% to 0.92% (median 0.13%) and correlated significantly (r=0.801, P<0.001) with increasing time after infusion.

CONCLUSIONS

After the intravenous administration of LAmB, AmB CSF levels were low, confirming published animal data. CSF levels remained at a steady-state level for longer than 48 h. As indicated by published post mortem data, higher levels in brain tissue, which would be necessary for the successful treatment of CNS infections, might be possible.

Performance of the definitions of the systemic inflammatory response syndrome and sepsis in neonates

AIMS

The aim of this study was to examine the applicability of the definitions of the systemic inflammatory response syndrome (SIRS) and sepsis to neonates during the first 3 days of life.

METHODS

This is a retrospective study of all term neonates hospitalized within the first 24 h of life from 2004 to 2010 at our neonatal intensive care unit.

RESULTS

Of 476 neonates, 30 (6 %) had a diagnosis of culture-proven early-onset sepsis (EOS) and 81 (17 %) had culture-negative clinical EOS or suspected EOS. SIRS and sepsis criteria were applied to 116 (24 %) and 61 (13 %) neonates, respectively. Of 30 neonates with culture proven, EOS 14 (53 %) fulfilled SIRS and sepsis criteria. The single diagnostic criterion of SIRS applied to 20 % (hypothermia or fever), 43 % (white blood cell count/immature-to-total neutrophil ratio), 87 % (respiratory symptoms), and 33 % (cardiocirculatory symptoms) of all neonates with culture-proven EOS.

CONCLUSIONS

The definitions of SIRS and sepsis did not apply to about half of all cases of culture-proven EOS. An evidence-based approach to find the appropriate criteria for defining EOS in the neonate is needed.

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.

Neonates presenting with temperature symptoms: role in the diagnosis of early onset sepsis

BACKGROUND

In this study, we aimed to evaluate the role of fever, hypothermia, and temperature instability in term and preterm newborns during the first 3 days of life and to identify risk factors for early onset sepsis (EOS) among newborns presenting with these temperature symptoms.

METHODS

In this retrospective cohort study set in our level III neonatal intensive care unit, we included all newborns hospitalized within the first 24 h of life from 2004 to 2007.

RESULTS

Of 851 newborns, 127 presented with temperature symptoms during the first 3 days of life (15%): 69 had fever, 69 had hypothermia, and 55 had temperature instability (8%, 8%, and 6%, respectively). Of 127 newborns presenting with temperature symptoms, 14 had culture-proven EOS/pneumonia (33% of all 42 newborns with culture-proven EOS/pneumonia), 67 had clinical EOS (30% of all 209 newborns with clinical EOS) and 46 were EOS-negative (8% of all 600 EOS-negatives). Factors associated with culture-proven EOS/pneumonia in newborns presenting with temperature symptoms were maternal fever (P = 0.009), chorioamnionitis (P < 0.001), antibiotic therapy of the mother (P = 0.04), poor skin color (P = 0.001) and syndrome of persistent fetal circulation (P = 0.01).

CONCLUSIONS

Every seventh newborn hospitalized at our neonatal intensive care unit developed fever, hypothermia and/or temperature instability during the first 3 days of life. Two-thirds of them had culture-proven or clinical sepsis. Temperature symptoms were rarely observed in EOS-negative newborns (8%) but despite low sensitivity, were highly specific for bacterial infection in preterm and term newborns.

Inflammatory indices in meconium aspiration syndrome

INTRODUCTION

Meconium aspiration syndrome (MAS) is linked to inflammation, but data on the patterns of hematological indices and C-reactive protein (CRP) in MAS are lacking. The aim of the study was to evaluate CRP, white blood cell count (WBC), absolute neutrophil count (ANC), and immature-to-total neutrophil ratio (IT-ratio) in MAS and to assess their association with disease severity.

METHODS

Retrospective cross-sectional study including 239 consecutively admitted neonates with MAS to a level III NICU. Neonates with early onset sepsis were excluded. Results Neonates with severe MAS (invasive mechanical ventilation for <7 days) and very severe MAS (invasive mechanical ventilation for ≥7 days or high frequency ventilation or ECMO) had higher CRP and IT-ratio compared to neonates with non-severe MAS (no invasive mechanical ventilation) during the first 2 days of life (CRP: 13.0 and 40.9 vs. 9.5 mg/L, P = 0.039 and <0.001, respectively) and neonates with very severe MAS had lower WBC and ANC. All four inflammatory indices correlated significantly with duration of invasive mechanical ventilation, duration of respiratory support and with length of hospital stay, arterial hypotension, and persistent pulmonary hypertension. Neonates with all four inflammatory indices beyond the normal range had a more than 20-fold increase in risk for very severe MAS.

CONCLUSION

High CRP and IT-ratio and low WBC and ANC values were closely linked to a more severe course of MAS during the early phases of the disease. These findings reflect the role of inflammation in the pathogenesis of MAS. Pediatr Pulmonol. 2016;51:601-606. 2015 Wiley Periodicals, Inc.

Serum bile acids in term and preterm neonates: A case-control study determining reference values and the influence of early-onset sepsis

Serum bile acids (BA) reference values are lacking for neonates. Therefore, this study aimed to determine serum BA reference values in term and preterm neonates. Furthermore, as serum BA concentrations are well-known to rise in septic adults, BA values were determined in early-onset neonatal sepsis (EOS), a common and serious disease in neonates.Using high-performance liquid chromatography-high-resolution mass spectrometry (HPLC-HRMS), we profiled serum BA in 236 infants, including healthy term neonates (n = 84), premature infants (n = 101), and both term infants (n = 35) and preterm infants (n = 16) with EOS. We examined the impact of prematurity and EOS on BA concentrations.The median reference values of serum BA were 8.0 μmol/L, interquartile range (IQR): 4.6 to 12.9, in healthy term neonates and 10.1 μmol/L, IQR: 5.7 to 15.7, in preterm neonates. Neonates with EOS had significantly lower median BA values, term (4.7 μmol/L, IQR: 2.7-7.6; P < 0.01) as well as preterm (6.4 μmol/L, IQR: 3.5-8.4; P < 0.01). Furthermore, primary and conjugated BA were most abundant in all groups. Taurine-conjugated BA were predominant in all neonates; glycine-conjugated BA were significantly lower in term neonates with EOS than in controls (P < 0.05). Multivariate regression analysis results obtained for BA and inflammatory parameters revealed that BA are an independent factor associated with EOS.This is the first study to determine standard value ranges of serum BA in neonates using HPLC-HRMS. In contrast to adults with sepsis, neonates suffering from EOS exhibit significantly lower BA values than do controls of the same gestational age. These data suggest BA as a supplementary parameter within a panel of biomarkers for EOS in the future.

Age- and gender-related differences in teicoplanin levels in paediatric patients

OBJECTIVES

Teicoplanin is a glycopeptide antibiotic active against Gram-positive bacteria, including methicillin-resistant staphylococci. While teicoplanin trough levels (TTLs) >10 mg/L are commonly considered appropriate, levels >20 mg/L are aimed for in the treatment of severe infections. Due to toxicity, it is recommended to avoid levels >60 mg/L.

PATIENTS AND METHODS

In our institution, the initial dosing schedule of teicoplanin (10-15 mg/kg every 12 h for three loading doses and every 24 h thereafter) is adapted according to TTLs analysed by a fluorescence polarization immunoassay on treatment days 2 to 4. Teicoplanin peak levels (TPLs) are analysed in selected cases 30 min after the end of infusion. In a retrospective analysis we evaluated 1357 TTLs and 333 TPLs from 410 treatment episodes from 2005 to 2011.

RESULTS

Initial TTLs were <10 mg/L in 14.1% and <20 mg/L in 72.6% of episodes. Toddlers had significantly lower TTLs, with a 2-fold and 2.5-fold increased risk of having levels <10 mg/L (24.6%) and <20 mg/L (82.6%), respectively. For the entire cohort, follow-up TTLs were less likely to be <10 mg/L and more likely to be >20 mg/L when compared with initial TTLs (P < 0.001, each). Adolescent girls had significantly higher initial TPLs (P = 0.001) and significantly higher follow-up TTLs (P = 0.016) than adolescent boys. In parallel, adolescent girls had initial TPLs >60 mg/L significantly more frequently (P = 0.012) and follow-up TTLs <10 mg/L significantly less frequently (P = 0.005).

CONCLUSIONS

More tailored dosing regimens with higher loading doses, especially for toddlers, should be considered. While further pharmacokinetic data in paediatric patients are pending, therapeutic drug monitoring is mandatory.

Prospective evaluation of clinical scoring systems in infants with bronchiolitis admitted to the intensive care unit

The objective of this investigation was to compare different scoring systems to assess the severity of illness in infants with bronchiolitis admitted to a tertiary paediatric intensive care unit (PICU). Over an 18-year period (1990-2007), infants with bronchiolitis aged up to 12 months and admitted to the PICU were prospectively scored using the Pediatric Risk of Mortality III (PRISM III) score, the Organ System Failure (OSF) score and the Acute Physiologic Score for Children (APSC) within 24 h. Infants were compared as to whether or not bronchiolitis was associated with respiratory syncytial virus (RSV). There was no difference between 113 RSV-positive and 80 RSV-negative infants regarding gestational age, birth weight, rate of premature delivery or bronchopulmonary dysplasia (BPD). The PRISM III score differed significantly between RSV-positive and RSV-negative cases (3.27 ± 0.39 vs. 1.96 ± 0.44, p = 0.006), as did the OSF score (0.56 ± 0.05 vs. 0.35 ± 0.06, p = 0.049) and the APSC (5.16 ± 0.46 vs. 4.1 ± 0.53, p = 0.048). All scores were significantly higher in the subgroup with mechanical ventilation (p < 0.0001). The mean time of ventilation was significantly higher in the RSV-positive group compared to the RSV-negative group (6.39 ± 1.74 days vs. 2.4 ± 0.47 days, p < 0.001). Infants suffering from RSV-positive bronchiolitis had higher clinical scores corresponding with the severity of bronchiolitis.

Long-Term Respiratory Support for Children and Adolescents in Austria: A National Survey

BACKGROUND

Population-based data on pediatric patients on long-term respiratory support (LTRS) in Austria are lacking. This study aimed to record the pediatric departments active in this field, as well as number and characteristics of patients on LTRS.

METHODS

A national cross-sectional study was carried out by means of questionnaires sent to all pediatric departments in Austria.

RESULTS

All departments answered to the questionnaires. On June 1st, 2013, the reference day for this study, 12 of the 41 pediatric departments in Austria were active in the field. At this time, these centers were caring for 143 patients, 111 (77.6%) of them under 18 years, which corresponds to a prevalence of 7.4 per 100 000. The patients suffered from neuromuscular disorders (44%), other neurological disorders (18.9%), disorders of respiratory drive (9.1%), obstructive sleep apnea (8.4%), thoracal and spinal diseases (8.4%), pulmonary disorders (4.9%) and other diseases (6.3%). Continuous positive airway pressure was used in 6.3%, non-invasive ventilation in 60.1% and invasive ventilation in 33.6% of the patients, respectively. LTRS was performed at home in 92.3%.

CONCLUSION

LTRS represents a common management strategy in children and adolescents with a variety of disorders. Census reports such as this one provide the basis for appropriate planning of resource allocation. The age distribution of our patients shows the need for structured transition into adult care.

Seasonal differences and within-canopy variations of antioxidants in mature spruce (Picea abies) trees under elevated ozone in a free-air exposure system

The effect of free-air ozone fumigation and crown position on antioxidants were determined in old-growth spruce (Picea abies) trees in the seasonal course of two consecutive years (2003 and 2004). Levels of total ascorbate and its redox state in the apoplastic washing fluid (AWF) were increased under double ambient ozone concentrations (2xO3), whilst ascorbate concentrations in needle extracts were unchanged. Concentrations of apoplastic and symplastic ascorbate were significantly higher in 2003 compared to 2004 indicating a combined effect of the drought conditions in 2003 with enhanced ozone exposure. Elevated ozone had only weak effects on total glutathione levels in needle extracts, phloem exudates and xylem saps. Total and oxidised glutathione concentrations were higher in 2004 compared to 2003 and seemed to be more affected by enhanced ozone influx in the more humid year 2004 compared to the combined effect of elevated ozone and drought in 2003 as observed for ascorbate.

Significance of ozone exposure for inter-annual differences in primary metabolites of old-growth beech (Fagus sylvatica L.) and Norway spruce (Picea abies L.) trees in a mixed forest stand

The influence of long-term free-air ozone fumigation and canopy position on leaf contents of total glutathione, its redox state, non-structural proteins (NSP), soluble amino compounds, and total soluble sugars in old-growth beech (FAGUS SYLVATICA) and spruce (PICEA ABIES) trees were determined over a period of five years. Ozone fumigation had weak effects on the analysed metabolites of both tree species and significant changes in the contents of total glutathione, NSP, and soluble sugars were observed only selectively. Beech leaves were affected by crown position to a higher extent than spruce needles and exhibited lower contents of total glutathione and NSP and total soluble sugars, but enhanced contents of oxidised glutathione and amino compounds in the shade compared to the sun crown. Contents of total soluble sugars generally were decreased in shade compared to sun needles of spruce trees. Interspecific differences between beech and spruce were more distinct in the sun compared to the shade crown. Contents of total glutathione were increased whilst contents of amino compounds and total soluble sugars were lower in spruce needles compared to beech leaves. The metabolites determined showed individual patterns in the course of the five measurement years. Contents of total glutathione and its redox state correlated with air temperature and global radiation, indicating an important role for the antioxidant at low temperatures. Correlations of glutathione with instantaneous ozone concentrations seem to be a secondary effect. Differences in proteins and/or amino compounds in the inter-annual course are assumed to be a consequence of alterations in specific N uptake rates.

[Improvement of Psychosomatic Rehabilitation after Prestationary Intervention]

Aim of the study: Improvement of psychosomatic rehabilitation efforts with prestationary intervention. Method: The study is designed as a prospective and randomisized interventon study including 317 in patients. Result: Most of the patients were women (69.4 %), the mean age was 50.2 years. As measured with the BDI-II patients with prestationary intervention improved more than patients without intervention. The motivation has not been changed significantly in both treatment arms. Various independent cofactors like long duration of unemployment, disablement and patients who apply to pension were identified. Conclusion: Finally a prestationary telephon interview improves the results of psychosomatic rehabilitation measured with BDI.

Definitions of SIRS and sepsis in correlation with early and late onset neonatal sepsis

Objective: To examine the applicability of the 2002 International Pediatric Sepsis Consensus Conference definitions of the systemic inflammatory response syndrome (SIRS) and sepsis to term and preterm newborns in the diagnosis of early (EOS) and late onset sepsis (LOS). Methods: Retrospective cohort study including 1) all newborns with hospitalization within the first 72 hours of life and 2) infants with episodes of suspected LOS at a tertiary care neonatal intensive care unit between 2004 and 2008, and correlating the definitions of SIRS and sepsis with culture proven and clinical EOS and LOS. Results: Association with EOS: Among term newborns SIRS and sepsis definitions applied to 62 and 39/245 newborns (25% and 16%, respectively) and to 5/13 cases of culture proven EOS (38%) and 34/66 cases of clinical EOS (52%), respectively. Among preterm newborns SIRS and sepsis definitions applied to 202 and 124/505 newborns (40% and 25%, respectively) and to 17/24 cases of culture proven EOS (71%) and 107/160 cases of clinical EOS (67%), respectively. Sensitivity of SIRS and sepsis definitions was higher in preterm compared to term newborns in case of culture proven and clinical EOS (p=.047 and p=0.03, respectively). Association with LOS: SIRS and sepsis definitions applied to 5/5 episodes of culture proven LOS (100%) and to 4/9 episodes of clinical LOS (44%) in newborns who were term at onset of sepsis (corrected gestational age) and to 14/19 episodes of culture proven LOS (74%) and 24/28 episodes of clinical LOS (86%) in preterm newborns. Conclusion: The definitions of SIRS and sepsis correlated well with LOS but poorly with EOS, where nearly two thirds of term and one quarter of preterm newborns would have been missed. Postnatal age rather than gestational age had a positive influence on the correlation.