How reliable is a negative blood culture result? Volume of blood submitted for culture in routine practice in a children's hospital

Neurodevelopmental outcomes following neonatal late-onset sepsis and blood culture-negative conditions

OBJECTIVE

Determine risk of death or neurodevelopmental impairment (NDI) in infants with late-onset sepsis (LOS) versus late-onset, antibiotic-treated, blood culture-negative conditions (LOCNC).

DESIGN

Retrospective cohort study.

SETTING

24 neonatal centres.

PATIENTS

Infants born 1/1/2006-31/12/2014, at 22-26 weeks gestation, with birth weight 401-1000 g and surviving >7 days were included. Infants with early-onset sepsis, necrotising enterocolitis, intestinal perforation or both LOS and LOCNC were excluded.

EXPOSURES

LOS and LOCNC were defined as antibiotic administration for ≥5 days with and without a positive blood/cerebrospinal fluid culture, respectively. Infants with these diagnoses were also compared with infants with neither condition.

OUTCOMES

Death or NDI was assessed at 18-26 months corrected age follow-up. Modified Poisson regression models were used to estimate relative risks adjusting for covariates occurring ≤7 days of age.

RESULTS

Of 7354 eligible infants, 3940 met inclusion criteria: 786 (20%) with LOS, 1601 (41%) with LOCNC and 1553 (39%) with neither. Infants with LOS had higher adjusted relative risk (95% CI) for death/NDI (1.14 (1.05 to 1.25)) and death before follow-up (1.71 (1.44 to 2.03)) than those with LOCNC. Among survivors, risk for NDI did not differ between the two groups (0.99 (0.86 to 1.13)) but was higher for LOCNC infants (1.17 (1.04 to 1.31)) compared with unaffected infants.

CONCLUSIONS

Infants with LOS had higher risk of death, but not NDI, compared with infants with LOCNC. Surviving infants with LOCNC had higher risk of NDI compared with unaffected infants. Improving outcomes for infants with LOCNC requires study of the underlying conditions and the potential impact of antibiotic exposure.

Clinical Utility of Molecular Tests for Guiding Therapeutic Decisions in Bloodstream Staphylococcal Infections: A Meta-Analysis

Background: Treatment of bloodstream staphylococcal infections (BSI) necessitates the prompt initiation of appropriate antimicrobial agents and the rapid de-escalation of excessive broad-spectrum coverage to reduce the risk of mortality. We, therefore, aimed to demonstrate the diagnostic accuracy of nucleic acid amplification tests (NAAT) for the identification of methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) in clinically suspected patients. Methods: Until November 23, 2020, databases including PubMed, Scopus, Embase, and Web of Science were scanned for eligible studies. A bivariate random-effects model was used for meta-analysis of the 33 included studies obtained from 1606 citations, and pooled summary estimates with 95% confidence intervals (CI) were generated. Results: Twenty-three studies (n = 8,547) assessed NAAT accuracy for MSSA detection, while three studies (n = 479) evaluated MRSA detection in adults. The pooled NAAT sensitivity and specificity for MRSA in adults was higher [sensitivity: 0.83 (95% CI 0.59-0.96), specificity: 0.99 (95% CI 0.98-1.0)] as compared to MSSA [sensitivity: 0.76 (95% CI 0.69-0.82), specificity: 0.98 (95% CI 0.98-0.99)]. Similarly, eight studies (n = 4,089) investigating MSSA in pediatric population reported higher NAAT accuracy [sensitivity: 0.89 (95% CI 0.76-0.96), specificity: 0.98 (95% CI 0.97-0.98)] compared to adults. Among NAA tests, SeptiFast (real-time PCR, commercial) was frequently applied, and its diagnostic accuracy corresponded well to the overall summary estimates. A meta-regression and subgroup analysis of study design, sample condition, and patient selection method could not explain the heterogeneity (P > 0.05) in the diagnostic efficiency. Conclusions: NAAT could be applied as the preferred initial tests for timely diagnosis and BSI management.

Problem-solving in clinical practice: Persisting respiratory distress in a premature infant

The deterioration of a previously stable preterm infant is a common scenario on the neonatal unit. The the most common bacterial causes of deterioration are nosocomial infections, such as coagulase-negative Staphylococcus and Staphylococcus aureus Non-infective conditions such as pulmonary haemorrhage, anaemia of prematurity and necrotising enterocolitis may also cause preterm infants to deteriorate. This case chronicles the unusual diagnostic journey of an infant born at 27+1 weeks who deteriorated at 26 days of life and did not respond to antimicrobial therapy as anticipated.

How to interpret a paediatric blood culture

Blood culture is one of the most important diagnostic tests in medicine, considering the significant morbidity and mortality associated with bloodstream infection (BSI). However, it is an often misused and misinterpreted test in everyday paediatric practice. In this article, we explore the evidence related to paediatric blood cultures, with the aim of providing clear and clinically-relevant recommendations for its judicious use.

miRNomic Signature in Very Low Birth-Weight Neonates Discriminates Late-Onset Gram-Positive Sepsis from Controls

Background and Objectives. Neonatal sepsis is a serious condition with a high rate of mortality and morbidity. Currently, the gold standard for sepsis diagnosis is a positive blood culture, which takes 48–72 h to yield results. We hypothesized that identifying differentially expressed miRNA pattern in neonates with late-onset Gram-positive sepsis would help with an earlier diagnosis and therapy. Methods. This is a prospective observational study in newborn infants with late-onset Gram positive bacterial sepsis and non-septic controls. Complementary to blood culture, an aliquot of 0.5 mL of blood was used to determine small non-coding RNA expression profiling using the GeneChip miRNA 4.0 Array. Results. A total of 11 very low birth-weight neonates with late-onset Gram-positive sepsis and 16 controls were analyzed. Further, 217 differentially expressed miRNAs were obtained between both groups. Subsequently, a combined analysis was performed with these miRNAs and 4297 differentially expressed genes. We identified 33 miRNAs that regulate our mRNAs, and the most relevant biological processes are associated with the immune system and the inflammatory response. Conclusions. The miRNA profiling in very low birth-weight neonates distinguishes late-onset Gram-positive sepsis versus control neonates.

Next-generation sequencing diagnostics of bacteremia in pediatric sepsis

INTRODUCTION

Sepsis and septic shock are the most severe forms of infection affecting predominantly elderly people, preterm and term neonates, and young infants. Even in high-income countries sepsis causes about 8% of admissions to pediatric intensive care units (PICUs). Early diagnosis, rapid anti-infective treatment, and prompt hemodynamic stabilization are crucial for patient survival. In this context, it is essential to identify the causative pathogen as soon as possible to optimize antimicrobial treatment. To date, culture-based diagnostic procedures (e.g., blood cultures) represent the standard of care. However, they have 2 major problems: on the one hand, in the case of very small sample volumes (and thus usually in children), they are not sufficiently sensitive. On the other hand, with a time-to-result of 2 to 5 days, blood cultures need a relatively long time for the anti-infective therapy to be calculated. To overcome these problems, culture-independent molecular diagnostic procedures such as unbiased sequence analysis of circulating cell-free DNA (cfDNA) from plasma samples of septic patients by next-generation sequencing (NGS) have been tested successfully in adult septic patients. However, these results still need to be transferred to the pediatric setting.

METHODS

The Next GeneSiPS-Trial is a prospective, observational, non-interventional, multicenter study used to assess the diagnostic performance of an NGS-based approach for the identification of causative pathogens in (preterm and term) neonates (d1-d28, n = 50), infants (d29 to <1 yr, n = 50), and toddlers (1 yr to <5 yr, n = 50) with suspected or proven severe sepsis or septic shock (according to the pediatric sepsis definition) by the use of the quantitative sepsis indicating quantifier (SIQ) score in comparison to standard of care (culture-based) microbiological diagnostics. Potential changes in anti-infective treatment regimens based on these NGS results will be estimated retrospectively by a panel of 3 independent clinical specialists.

DISCUSSION

Neonates, infants, and young children are significantly affected by sepsis. Fast and more sensitive diagnostic approaches are urgently needed. This prospective, observational, non-interventional, multicenter study seeks to evaluate an NGS-based approach in critically ill children suffering from sepsis.

TRIAL REGISTRATION

DRKS-ID: DRKS00015705 (registered October 24, 2018). https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00015705.

Comparison of Microorganism Detection and Time to Positivity in Pediatric and Standard Media from Three Major Commercial Continuously Monitored Blood Culture Systems

New blood culture instrumentation and medium formulations have led to improved time to positivity (TTP) for positive blood cultures. Data regarding the necessity of pediatric blood culture bottles with contemporary blood culture systems are sparse. We compared performance of three commercial blood culture systems, evaluating impact of blood volumes in standard and pediatric blood culture media across systems. Simulated blood cultures with packed red blood cells (PRBCs) and three Gram-positive, four Gram-negative, and one anaerobic organism (final concentrations ranging from 0.5 to 19 CFU/ml blood) on the Virtuo, VersaTrek, and Bactec FX instruments were evaluated with FAN Plus, Redox, and Bactec Plus media, respectively. For each medium/instrument/organism combination, 1-, 3-, 5-, and 10-ml blood volumes were evaluated in triplicate. Detection rate was not affected by blood volume. Aerobic organisms that demonstrated variable rates of detection were Kingella kingae, Haemophilus influenzae, and Neisseria meningitidis. Bacteroides fragilis was detected in 83%, 100%, and 100% of Virtuo, VersaTrek, and Bactec anaerobic bottles, respectively. The average TTP of standard medium for aerobic organisms detected on Virtuo was decreased compared to those for VersaTrek (-2.3 h) and Bactec (-4.9 h). Compared to standard medium, detection rate and TTP were unchanged on Virtuo, while TTP was reduced with pediatric medium for 2/8 organisms tested on Bactec and 7/8 organisms on VersaTrek, illustrating the potential benefit of pediatric medium on VersaTrek or Bactec when low blood volumes (<5 ml) are collected. These results demonstrate that TTP is decreased on the Virtuo compared to VersaTrek and Bactec for many microorganisms associated with bloodstream infection (BSI) but may have species-specific limitations.

Neonatal sepsis at point of care

Sepsis, which includes infection followed by inflammation, is one of the leading causes of death among neonates worldwide. The major attribute of this disease process is dysregulated host response to infection leading to organ dysfunction and potentially death. A comprehensive understanding of the host response as well as the pathogen itself are important factors contributing to outcome. Early diagnosis is paramount, as it leads to accurate assessment and improved clinical management. Accordingly, a number of diagnostic platforms have been introduced to assess the presence of blood stream pathogens in septic neonates. Unfortunately, current point-of-care (POC) methods rely on a single parameter/biomarker and thus lack a comprehensive evaluation. The emerging field of biosensing has, however, resulted in the development of a wide range of analytical devices that may be useful at POC. This review discusses currently available methods to screen the inflammatory process in neonatal sepsis. We describe POC sensor-based methods for single platform multi-analyte detection and highlight the latest advances in this evolving technology. Finally, we critically evaluate the applicability of these POC devices clinically for early diagnosis of sepsis in neonates.

Antibiotic Stewardship for the Neonatologist and Perinatologist

Antibiotic use is common in the neonatal intensive care unit. The density and heterogeneity of antibiotic prescribing suggests inappropriate and overuse of these agents. Potential antibiotic stewardship targets include sepsis, necrotizing enterocolitis, and perioperative prophylaxis. Diagnostic stewardship principles, including appropriately obtained cultures, may be leveraged to decrease unnecessary antibiotic prescribing. Strategies including guideline development, prospective audit and feedback, and formulary restriction have been successfully deployed in the neonatal intensive care unit to improve the quality of antibiotic prescribing. Implementation of antibiotic stewardship in the neonatal intensive care unit requires multidisciplinary collaboration between neonatologists, surgeons, infectious diseases specialists, pharmacists, and nurses.

Biomarkers for the Diagnosis of Neonatal Sepsis

Neonatal sepsis is a major cause of morbidity and mortality in neonates and is challenging to diagnose. Infants manifest nonspecific clinical signs in response to sepsis; these signs may be caused by noninfectious conditions. Time to antibiotics affects neonatal sepsis outcome, so clinicians need to identify and treat neonates with sepsis expeditiously. Clinicians use serum biomarkers to measure inflammation and infection and assess the infant's risk of sepsis. However, current biomarkers lack sufficient sensitivity or specificity to be consider useful diagnostic tools. Continued research to identify novel biomarkers as well as novel ways of measuring them is sorely needed.

Survey on antibiotic regimens for necrotizing enterocolitis prescribed by Chinese pediatricians in 2020

Background

Necrotizing enterocolitis (NEC) is a serious intestinal inflammatory disease in neonates, and intravenous antibiotics constitute the main therapeutic strategy. Studies have shown that substantial variation in the selection of antibiotic regimens for NEC remains in many countries. The variability in antibiotic therapy selection in China is unclear.

Methods

A cross-sectional study using an online questionnaire regarding antibiotic regimens for NEC was conducted among pediatricians working in tertiary hospitals in China.

Results

A total of 284 pediatricians from 29 provinces completed the survey; 37.9% of them administered one antibiotic, 56.7% administered two antibiotics and 2.4% administered three antibiotics. The top three single-antibiotic regimens for NEC were beta-lactamase inhibitors (n=66, 41.5%), carbapenems (n=46, 28.9%) and cephalosporins (n=33, 20.8%). Twenty combinations of two antibiotics were identified, and the top three combinations were beta-lactamase inhibitors and antianaerobic agents (n=49, 19.6%), carbapenems and glycopeptides (n=42, 16.8%), and cephalosporins and antianaerobic agents (n=37, 14.8%). Regarding the therapeutic duration of antibiotic treatment, 77.5% (n=220) of the pediatricians chose 5–10 days for stage II NEC, and 79.6% (n=226) chose 7–14 days for stage III NEC. Forty-three percent (n=122) of the respondents preferred to use carbapenems when NEC was diagnosed, and 83.3% (n=135) adjusted the antibiotics to carbapenems if a patient’s medical condition deteriorated or if the therapeutic efficacy was poor.

Conclusion

This survey revealed that carbapenems were the most common antibiotics selected when NEC was diagnosed or a patient’s condition deteriorated, but the duration of the course of treatment for NEC varied substantially among doctors.

Diagnostic Yield of Initial and Consecutive Blood Cultures in Children With Cancer and Febrile Neutropenia

BACKGROUND

The timing and necessity of repeated blood cultures (BCs) in children with cancer and febrile neutropenia (FN) are unknown. We evaluated the diagnostic yield of BCs collected pre- and post-empiric FN antibiotics.

METHODS

Data collected prospectively from the Australian Predicting Infectious ComplicatioNs in Children with Cancer (PICNICC) study were used. Diagnostic yield was calculated as the number of FN episodes with a true bloodstream infection (BSI) detected divided by the number of FN episodes that had a BC taken.

RESULTS

A BSI was identified in 13% of 858 FN episodes. The diagnostic yield of pre-antibiotic BCs was higher than of post-antibiotic cultures (12.3% vs 4.4%, P < .001). Two-thirds of the post-antibiotic BSIs were associated with a new episode of fever or clinical instability, and only 2 new BSIs were identified after 48 hours of empiric antibiotics and persistent fever. A contaminated BC was identified more frequently in post-antibiotic cultures.

CONCLUSIONS

In the absence of new fever or clinical instability, BCs beyond 48 hours of persistent fever have limited yield. Opportunity exists to optimize BC collection in this population and reduce the burden of unnecessary tests on patients, healthcare workers, and hospitals.

Turkish pediatric residents' knowledge, perceptions, and practices of blood culture sampling

INTRODUCTION

Pediatrics is one of the medical specialties in which blood cultures for bloodstream infections are performed very frequently. This study aimed to evaluate pediatric residents' knowledge and perceptions of blood culture sampling.

MATERIAL AND METHODS

Between June 2019 and September 2019, a questionnaire comprising 20 questions about blood culture sampling was sent via email to participants who were pediatric residents at five different hospitals in Turkey. There were 11 true/false and nine multiple-choice questions that assessed three aspects of culture sampling: indications, sampling practice and knowledge, and contamination. The percentage of correct answers was used to calculate an overall score and subsection scores.

RESULTS

A total of 132 pediatric residents [102 (77%) female] with a mean age of 28.3±2.8 years completed the questionnaire. Forty-five (35%) were in their 1st year of residency. Sixty (46%) participants reported that they had not performed blood culture sampling in the last week. There was a negative relationship between years in training and the number of cultures performed (Kendal's tau-b=-0.297, p<0.001). The overall median score was 65 (range, 35-90) and it seemed to increase with years of training. The lowest median score was in the contamination subscale and only one (0.76%) participant correctly answered all questions concerning contamination.

CONCLUSION

Residents who obtained the majority of blood cultures had the lowest knowledge levels. Therefore, it is evident that the knowledge levels of pediatric residents must be increased in order to improve blood culture sampling practices in centers where they perform blood culture sampling.

Infection Manager System (IMS) as a new hemocytometry-based bacteremia detection tool: A diagnostic accuracy study in a malaria-endemic area of Burkina Faso

BACKGROUND

New hemocytometric parameters can be used to differentiate causes of acute febrile illness (AFI). We evaluated a software algorithm-Infection Manager System (IMS)-which uses hemocytometric data generated by Sysmex hematology analyzers, for its accuracy to detect bacteremia in AFI patients with and without malaria in Burkina Faso. Secondary aims included comparing the accuracy of IMS with C-reactive protein (CRP) and procalcitonin (PCT).

METHODS

In a prospective observational study, patients of ≥ three-month-old (range 3 months- 90 years) presenting with AFI were enrolled. IMS, blood culture and malaria diagnostics were done upon inclusion and additional diagnostics on clinical indication. CRP, PCT, viral multiplex PCR on nasopharyngeal swabs and bacterial- and malaria PCR were batch-tested retrospectively. Diagnostic classification was done retrospectively using all available data except IMS, CRP and PCT results.

FINDINGS

A diagnosis was affirmed in 549/914 (60.1%) patients and included malaria (n = 191) bacteremia (n = 69), viral infections (n = 145), and malaria-bacteremia co-infections (n = 47). The overall sensitivity, specificity, and negative predictive value (NPV) of IMS for detection of bacteremia in patients of ≥ 5 years were 97.0% (95% CI: 89.8-99.6), 68.2% (95% CI: 55.6-79.1) and 95.7% (95% CI: 85.5-99.5) respectively, compared to 93.9% (95% CI: 85.2-98.3), 39.4% (95% CI: 27.6-52.2), and 86.7% (95% CI: 69.3-96.2) for CRP at ≥20mg/L. The sensitivity, specificity and NPV of PCT at 0.5 ng/ml were lower at respectively 72.7% (95% CI: 60.4-83.0), 50.0% (95% CI: 37.4-62.6) and 64.7% (95% CI: 50.1-77.6) The diagnostic accuracy of IMS was lower among malaria cases and patients <5 years but remained equal to- or higher than the accuracy of CRP.

INTERPRETATION

IMS is a new diagnostic tool to differentiate causes of AFI. Its high NPV for bacteremia has the potential to improve antibiotic dispensing practices in healthcare facilities with hematology analyzers. Future studies are needed to evaluate whether IMS, combined with malaria diagnostics, may be used to rationalize antimicrobial prescription in malaria endemic areas.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT02669823) https://clinicaltrials.gov/ct2/show/NCT02669823.

Diagnostic Accuracy of Clinical Tool 'STOPS' and Serum Procalcitonin for Optimizing Antibiotic Therapy in Neonates Born at ≥ 28 Weeks of Gestation with Neonatal Sepsis

BACKGROUND

Antibiotic therapy is initiated in neonates on suspicion of sepsis. Optimizing therapy is a felt need of clinicians as prolonged injudicious use increases mortality and morbidity risk.

OBJECTIVE

To evaluate the diagnostic accuracy of clinical tool 'STOPS' and serum procalcitonin (PCT) for identifying neonates with early-onset neonatal sepsis (EONS) or late-onset neonatal sepsis (LONS) and early discontinuation in those with no sepsis.

METHODS

The study had a prospective analytical design conducted at a tertiary care hospital. Consecutively admitted neonates with suspected EONS or LONS were enrolled. The 'STOPS' tool comprising sensorium, temperature, oxygenation, perfusion, skin color, and blood sugar was applied at 6 and 12 hours of enrollment. Serum PCT was sent at 12 hr. The sensitivity, specificity, positive and negative predictive value (PPV and NPV), positive and negative likelihood ratio (PLR and NLR) were estimated.

RESULTS

The study enrolled 380 neonates, of which 330 were given antibiotics for EONS and 50 for LONS. Temperature disturbance in the EONS group at 12 hr showed a PPV of 100% and a PLR of 9.1 (7.7 - 18). Perfusion assessment at 12 hr had a PPV of 77% and PLR of 8.25 (2.3 - 29). Skin color assessment at 12 hr had a PPV of 100% and PLR of 13.5 (9.7 - 27). The diagnostic accuracy of PCT in the EONS group was unremarkable. In the LONS group, skin color at 12 hr had a PPV of 100% and PLR of 11.2 (8.6 - 19.5). The diagnostic accuracy of PCT in the LONS group showed a PPV of 82% and PLR of 7 (1.7 - 29).

CONCLUSION

Identifying abnormal STOPS parameters was superior to PCT alone in EONS and as good as PCT in LONS. The 'STOPS' tool allows early identification of neonates with no sepsis, thereby optimizing antibiotic use.

Neonatal Escherichia coli infection in twins: clinical spectrum and management dilemma

The clinical manifestation of Escherichia coli could vary from asymptomatic bacteraemia to systemic bloodstream infection and meningitis. We describe an unusual course of E. coli infection in twins, emphasising commencement of appropriate antimicrobial therapy. A set of male dichorionic diamniotic twins were delivered at 34 weeks of gestation by caesarian section. Pregnancy was complicated by diabetes, pre-eclampsia and cholestasis. Antenatal ultrasounds noted a congenital pulmonary airway malformation in twin A. Following delivery, twin A developed respiratory distress, but twin B was asymptomatic. Partial septic work-up at admission in the neonatal intensve care unit was done. Twin A's blood culture grew E. coli, while twin B's blood culture was negative. Twin A was treated with 7 days of intravenous antibiotics. At 11 days of age, twin B acutely developed a scrotal swelling. On suspicion of testicular torsion, he was taken for urgent surgery, which revealed a scrotal abscess positive for E. coli The scrotum was irrigated and successfully treated with 4 weeks of antibiotics. Both twins were doing well at 3 months of follow-up.

Visual multiple cross displacement amplification for the rapid identification of S. agalactiae immediately from vaginal and rectal swabs

Streptococcus agalactiae (S. agalactiae) is an important pathogen that can lead to neonatus and mother infection. The current existing techniques for the identification of S. agalactiae are limited by accuracy, speed and high-cost. Therefore, a new multiple cross displacement amplification (MCDA) assay was developed for test of the target pathogen immediately from vaginal and rectal swabs. MCDA primers screening were conducted targeting S. agalactiae pcsB gene, and one set of MCDA primers with better rapidity and efficiency was selected for establishing the S. agalactiae-MCDA assay. As a result, the MCDA method could be completed at a constant temperature of 61 °C, without the requirement of special equipment. The detection limit is 250 fg (31.5 copies) per reaction, all S. agalactiae strains displayed positive results, but not for non-S. agalactiae strains. The visual MCDA assay detected 16 positive samples from 200 clinical specimen, which were also detected positive by enrichment/qPCR. While the CHROMagar culture detected 6 positive samples. Thus, the MCDA assay is prefer to enrichment/qPCR and culture for detecting S. agalactiae from clinical specimen. Particularly, the whole test of MCDA takes about 63.1 min, including sample collection (3 min), DNA preparation (15 min), MCDA reaction (45 min) and result reporting (6 s). In addition, the cost was very economic, with only US$ 4.9. These results indicated that our S. agalaciae-MCDA assay is a rapid, sensitive and cost-efficient technique for target pathogen detection, and is more suitable than conventional assays for an urgent detection, especially for 'on-site' laboratories and resource-constrained settings.

Association of early life antibiotics and health outcomes: Evidence from clinical studies

Preterm infants are susceptible to infections that can rapidly progress to disastrous outcomes. Antibiotics are lifesaving, but their prolonged and inappropriate use are associated with adverse outcomes. In this review, we discuss the current status of antimicrobial use in the preterm neonatal population, and the challenges in determining the initiation, duration, and choice of antibiotics. Finally, we review the clinical studies on the potential consequences of prolonged antimicrobial exposure in prematurely born infants.

Expanding antimicrobial stewardship strategies for the NICU: Management of surgical site infections, perioperative prophylaxis, and culture negative sepsis

OBJECTIVE

To review antibiotic stewardship strategies for neonatal intensive care units (NICU) in the areas of management of surgical site infections, perioperative prophylaxis and culture negative late onset sepsis.

FINDING

Review of local microbiology, stratification of surgical procedures by risk of contamination of the surgical site, and adherence to evidence-based principles of perioperative antibiotic administration (targeted therapy, effective dosing, appropriate timing and limiting duration post-operatively) can help to minimize unnecessary antibiotic use for neonatal surgery. Creating a late onset sepsis case definition, appropriate collection and interpretation of blood cultures, and instituting antibiotic time-outs can minimize the overuse of antibiotics for culture negative sepsis.

CONCLUSION

Effective implementation of these antimicrobial stewardship strategies in the NICU can reduce unnecessary antimicrobial use and limit the emergence of resistant pathogens.

Time to positivity of Klebsiella pneumoniae in blood culture as prognostic indicator for pediatric bloodstream infections

The aim of this study is to explore the prognostic values and optimal cutoff point of time to positivity (TTP) of blood culture in children with Klebsiella pneumoniae (K. pneumoniae) bloodstream infection. Ninety-four children with K. pneumoniae bloodstream infection hospitalized in Children's Hospital of Chongqing Medical University from April 2014 to January 2019 were enrolled retrospectively. TTP and risk factors were determined and analyzed by receiver operating characteristic (ROC) analysis and logistic regression analysis. The standard cutoff point of TTP was 13 h. Patients in early TTP (≤ 13 h) group had significantly higher in-hospital mortality (37.93% vs 6.15%, P = 0.000), higher incidence of septic shock (44.83% vs 6.15%, P = 0.000), higher proportion of PRISM III scores ≥ 10 (48.28% vs 20.00%, P = 0.005), and higher proportion of hypoalbuminemia on admission (44.83% vs 18.46%, P = 0.008). Multivariate analysis indicated PRISM III scores ≥ 10, early TTP, and hypoalbuminemia on admission were independent risk factors of in-hospital mortality (OR 8.36, 95% CI 1.80-38.92, P = 0.007; OR 5.85, 95% CI 1.33-25.61, P = 0.019; OR 5.73, 95% CI 1.30-25.22, P = 0.021, respectively) and septic shock (OR 14.04, 95% CI 2.63-75.38, P = 0.002; OR 11.26, 95% CI 2.10-60.22, P = 0.005; OR 10.27, 95% CI 2.01-52.35, P = 0.005, respectively).Conclusion: Early TTP (TTP ≤ 13 h), PRISM III scores ≥ 10, and hypoalbuminemia on admission appeared to be associated with worse outcomes for K. pneumoniae bloodstream infection children. What is Known: • Klebsiella pneumoniae bloodstream infection is an important cause of infectious disease morbidity and mortality worldwide in children. • Short duration of time to positivity indicated poor clinical outcomes. What is New: • Time to positivity ≤ 13 h, along with PRISM III scores ≥ 10 and hypoalbuminemia on admission, indicated higher in-hospital mortality and incidence of septic shock in Klebsiella pneumoniae bloodstream infection children. • The cut-off point of TTP in this pediatric study was much longer than that reported in adult patients.

The practice of blood volume submitted for culture in a neonatal intensive care unit

BACKGROUND

Neonatal sepsis is the leading cause of mortality and morbidity in neonatal intensive care units. The volume of blood taken for culture remains one of the most important factors in isolating microorganisms.

OBJECTIVES

To evaluate the impact of the intervention on the blood volume submitted for culture and to identify factors influencing the volume as determined by the phlebotomist.

METHODS

Blood culture volume was determined by weighing the culture bottle before and immediately after blood inoculation. A 3-month preintervention audit revealed that in 126/130 samples (96.9%), the volume of blood submitted was suboptimal. Multiple intervention measures were instituted, and volume was monitored over the next 9 months.

RESULTS

637 blood culture samples were included in the study, 130 were in preintervention and 507 were in postintervention epochs. Following the intervention, suboptimal volume samples reduced from 96.9% (126/130 samples) to 25% (126/507 samples), p<0.0001 and the median (IQR) sample volume improved from 0.36 (0.23) ml to 0.9 (0.27) ml, p<0.0001. Poor blood flow was identified as the most common reason for an inadequate sample.

CONCLUSION

The study underscores the role of educational intervention in improving the blood culture volume in newborn infants. Poor backflow from the cannula is an important cause of inadequate volume collection.

Morbidity and mortality due to surgical congenital malformations from the perspective of surgical neonatal ICU outside a maternity service: a retrospective cohort study

OBJECTIVE

To describe the characteristics of patients treated at a level III surgical Neonatal Intensive Care Unit outside of a maternity service and analyze possible risk factors for mortality in this population.

METHODS

A retrospective cohort study evaluating patients admitted to a level III surgical Neonatal Intensive Care Unit from June/2015 to November/2017. Univariate analysis was performed by the Chi-square test and T-student test or Mann-Whitney test. Multivariate analysis by logistic regression was performed including in the model the variables with a P-value <0.2 in univariate analysis. Kaplan-Meier curve and Log-Rank test were performed using the variables that were statistically associated with death in the multivariate analysis. A significance level of a=5% and an error B=80% were adopted.

RESULTS

During this period, 246 patients were admitted to this service. 58 (23.8%) patients died, with a mean time until death of 18 days. Half of the patients had a clinical diagnosis of sepsis (50.6%), blood culture was positive in 25.2%, and gram-positive bacteria (48.4%) were the main pathogens isolated. The variables that remained in the final model after multivariate analysis were diagnosis of congenital heart disease (OR = 4.5; p = 0.016), clinical diagnosis of sepsis (OR = 8.1; p = 0.000), and isolation of gram-positive bacteria in blood culture (OR = 3.9; p = 0.006).

CONCLUSION

The level III surgical Neonatal Intensive Care Unit outside of a maternity service has a different profile of morbidity and mortality, and death was associated with the diagnosis of congenital heart disease, the clinical diagnosis of sepsis, and the isolation of gram-positive bacteria in the blood culture.

Prognostic role of time to positivity of blood culture in children with Pseudomonas aeruginosa bacteremia

BACKGROUND

Pseudomonas aeruginosa (P. aeruginosa) is a major Gram-negative pathogen, which has been reported to result in high mortality. We aim to investigate the prognostic value and optimum cut-off point of time-to-positivity (TTP) of blood culture in children with P. aeruginosa bacteremia.

METHODS

From August 2014 to November 2018, we enrolled the inpatients with P. aeruginosa bacteremia in a 1500-bed tertiary teaching hospital in Chongqing, China retrospectively. Receiver operating characteristic (ROC) analysis was used to determine the optimum cut-off point of TTP, and logistic regression were employed to explore the risk factors for in-hospital mortality and septic shock.

RESULTS

Totally, 52 children with P. aeruginosa bacteremia were enrolled. The standard cut-off point of TTP was18 h. Early TTP (≤18 h) group patients had remarkably higher in-hospital mortality (42.9% vs 9.7%, P = 0.014), higher incidence of septic shock (52.4% vs12.9%, P = 0.06), higher Pitt bacteremia scores [3.00 (1.00-5.00) vs 1.00 (1.00-4.00), P = 0.046] and more intensive care unit admission (61.9% vs 22.6%, P = 0.008) when compared with late TTP (> 18 h) groups. Multivariate analysis indicated TTP ≤18 h, Pitt bacteremia scores ≥4 were the independent risk factors for in-hospital mortality (OR 5.88, 95%CI 1.21-21.96, P = 0.035; OR 4.95, 95%CI 1.26-27.50, P = 0.024; respectively). The independent risk factors for septic shock were as follows: TTP ≤18 h, Pitt bacteremia scores ≥4 and hypoalbuminemia (OR 6.30, 95%CI 1.18-33.77, P = 0.032; OR 8.15, 95%CI 1.15-42.43, P = 0.014; OR 6.46, 95% CI 1.19-33.19 P = 0.031; respectively).

CONCLUSIONS

Early TTP (≤18 hours) appeared to be associated with worse outcomes for P. aeruginosa bacteremia children.

Suspected Neonatal Sepsis: Tenth Clinical Consensus of the Ibero-American Society of Neonatology (SIBEN)

Suspected neonatal sepsis is one of the most common diagnoses made in newborns (NBs), but very few NBs actually have sepsis. There is no international consensus to clearly define suspected neonatal sepsis, but each time that this suspected diagnosis is assumed, blood samples are taken, venous accesses are used to administer antibiotics, and the mother-child pair is separated, with prolonged hospital stays. X-rays, urine samples, and a lumbar puncture are sometimes taken. This is of concern, as generally <10% and no more than 25%-30% of the NBs in whom sepsis is suspected have proven neonatal sepsis. It seems easy to start antibiotics with suspicion of sepsis, but stopping them is difficult, although there is little or no support to maintain them. Unfortunately, the abuse of antibiotics in inpatient and outpatient NBs is foolish. Its negative impact on neonatal health and the economy is a public health problem of epidemiological and even epidemic proportions. This manuscript is a shortened version of the 10^th Clinical Consensus of the Ibero-American Society of Neonatology (SIBEN) on suspected neonatal sepsis at the end of 2018, updated with publications from its completion to February 2020. This manuscript describes useful strategies for everyday neonatal practice when neonatal sepsis is suspected, along with important aspects about the indisputable value of clinical evaluation of the NB and about obtaining and interpreting blood cultures, urine cultures, and other cultures. Likewise, the low value of laboratory tests in suspected neonatal sepsis is demonstrated with evidence and clinical recommendations are made on the appropriate use of antibiotics.

ASSOCIATION BETWEEN SEPSIS RISK CALCULATOR AND INFECTION PARAMETERS FOR NEONATES WITH RISK OF EARLY ONSET SEPSIS

C-reactive protein (CRP) is an acute-phase reactant protein that is primarily induced by the IL-6 action during the acute phase of an inflammatory or infectious process. Bacterial infection is a potent stimulus, leading to a rapid elevation of CRP levels within hours while the CBC and symptom are often misleading and/or absent. American Academy of paediatrics (AAP) is recommended routine blood examination test Complete Blood Count (CBC), C-reactive protein (CRP), and blood culture along with empirical antibiotic in neonates with early onset sepsis risk (EOS) risk even asymptomatic. Previous study is showed there were no correlation of CRP and EOS risk. The aim of this study is to evaluate the CRP and CBC profile in neonate with risk of EOS.  Methods of this study is using the sepsis risk calculator (SRC) to calculate the probability of neonatal early onset sepsis (EOS) based on maternal risk and infant’s clinical presentation. Neonates with ≥34 weeks of gestation who were started on antibiotic treatment after laboratory examination and blo odculture were taken. EOS risk estimation were compared including CRP, leukocyte, and thrombocyte count. ANOVA applied to distinguished laboratory examination between stratified risk groups. The result is showed using 82 subjects who met the inclusion and exclusion criterias, EOS risk level was stratified into green, yellow, and red group. The p value of CRP level, platelets, white blood cell were 0.35,0.54 and 0.48 where p value was considered as significant if < 0.5. The conclusion of this study is there were no correlation of CRP level and EOS riskASSOCIATION BETWEEN SEPSIS RISK CALCULATOR AND INFECTION PARAMETERS FOR NEONATES WITH RISK OF EARLY ONSET SEPSIS

Soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) in neonatal sepsis

BACKGROUND

Efficient and accurate diagnosis of neonatal sepsis is challenging. The potential impact for a reduction in morbidity and mortality as well as antibiotic usage has stimulated the ongoing search for biomarkers of early sepsis. The objective of this pilot study was to quantify the levels of sTREM-1 and correlate with blood cultures and inflammatory markers in neonates evaluated for sepsis.

METHODS

Neonates with suspected sepsis were enrolled (n = 83; Preterm n = 35; Term n = 48). Routine bloods for sepsis evaluation were included and plasma sTREM-1 levels were quantified by ELISA.

RESULTS

Term and preterm neonates (n = 83; Preterm n = 35; Term n = 48) were enrolled and 16 neonates had positive blood cultures (preterm n = 15; term n = 1). sTREM-1 levels were not significantly different in infants with culture-positive or culture-negative sepsis (356 ± 218 pg/mL and 385 ± 254 pg/mL respectively). The immature-to-total granulocyte (I/T) ratio showed a significant positive correlation with sTREM-1 in the preterm group with positive blood cultures. Additionally, sTREM-1 showed a positive correlation with CRP in the preterm group with negative blood cultures.

CONCLUSIONS

sTREM-1 was associated with traditional markers of inflammation (I/T ratio and CRP). However, in this cohort sTREM-1 did not improve the early detection of neonatal culture-positive sepsis.

Time to Positivity of Neonatal Blood Cultures for Early-onset Sepsis

BACKGROUND

In newborns at risk for early-onset sepsis, empiric antibiotics are often initiated while awaiting the results of blood cultures. The duration of empiric therapy can be guided by the time to positivity (TTP) of blood cultures. The objective of the study was to determine the TTP of neonatal blood cultures for early-onset sepsis and the factors which may impact TTP.

METHODS

Observational study of blood cultures growing pathogenic species obtained within 72 hours of birth from infants born at 23-42 weeks gestation, at 19 hospitals in Northern California, Boston, and Philadelphia. TTP was defined as the time from blood culture collection to the time organism growth was reported by the microbiology laboratory.

RESULTS

A total of 594 blood cultures growing pathogenic bacteria were identified. Group B Streptococcus and Escherichia coli accounted for 74% of blood culture isolates. Median TTP was 21.0 hours (interquartile range, 17.1-25.3 hours). Blood cultures were identified as positive by 24 hours after they were obtained in 68% of cases; by 36 hours in 94% of cases; and by 48 hours in 97% of cases. Neither the administration of maternal intrapartum antibiotic prophylaxis, gestational age <35 weeks, nor blood culture system impacted median TTP.

CONCLUSIONS

Pathogens are isolated by 36 hours after blood culture collection in 94% of neonatal early blood cultures, regardless of maternal antibiotic administration. TTP information can inform decisions regarding the duration of empiric neonatal antibiotic therapies.

Effectiveness of antimicrobial stewardship programmes in neonatology: a systematic review

INTRODUCTION

Antimicrobial stewardship programmes (ASPs) are recommended to improve antibiotic use in healthcare and reduce antimicrobial resistance (AMR). Our aim was to investigate the effectiveness of ASPs in reducing antibiotic consumption, use of broad-spectrum/restricted antibiotics, antibiotic resistance and healthcare-associated infections (HAIs) in neonates.

METHODS

We searched PUBMED, SCIELO, EMBASE and the Cochrane Database (January 2000-April 2019) to identify studies on the effectiveness of ASPs in neonatal wards and/or neonatal intensive care units (NICUs). Outcomes were as follows: reduction of antibiotic consumption overall and of broad-spectrum/target antibiotics, inappropriate antibiotic use, antibiotic resistance and HAIs. ASPs conducted in settings other than acute care hospitals, for children older than 1 month, and ASPs addressing antifungal and antiviral agents, were excluded.

RESULTS

The initial search identified 53 173 titles and abstracts; following the application of filters and inclusion criteria, a total of six publications were included in the final analysis. All studies, of which one was multi-centre study, were published after 2010. Five studies were conducted exclusively in NICUs. Four articles applied multimodal interventions. Reduction of antibiotic consumption overall and/or inappropriate antibiotic use were reported by four articles; reduction of broad-spectrum/targeted antibiotics were reported by four studies; No article evaluated the impact of ASPs on AMR or the incidence of HAI in neonates.

CONCLUSION

ASPs can be effectively applied in neonatal settings. Limiting the use of broad-spectrum antibiotics and shorting the duration of antibiotic treatment are the most promising approaches. The impact of ASPs on AMR and HAI needs to be evaluated in long-term studies.

A narrative review of heart rate and variability in sepsis

Clinicians face challenges in the timely diagnosis and management of pediatric sepsis. Pediatric heart rate has been incorporated into early warning systems and studied as a predictor for critical illness. We aim to review: (I) the role of heart rate in pediatric warning systems and (II) the role of heart rate variability (HRV) in adult and neonatal sepsis, with a focus on its potential applications in pediatrics. We conducted a literature search for papers published up to December 2019 on the utility of heart rate and HRV analysis in the diagnosis and management of sepsis, using four medical databases: PubMed, Google Scholar, EMBASE and Web of Science. This review demonstrates that the clinical utility of pediatric heart rate in predicting clinical deterioration is limited by the lack of consensus among warning systems, consensus-based guidelines, and evidence-based studies as to what constitutes abnormal heart rate in the pediatric age group. Current studies demonstrate that abnormal heart rate itself does not adequately discriminate children with sepsis from those without. HRV analysis provides a quick and non-invasive method of assessment and can provide more information than traditional heart rate. HRV analysis has the potential to add value in identification and prognostication of adult and neonatal sepsis. With further studies to explore its role, HRV analysis has the potential to add to current tools in the diagnosis and prognosis of pediatric sepsis.

Blood culture sampling rate in hospitalised children as a quality indicator for diagnostic stewardship

PURPOSE

Recommendations regarding the optimal number of blood cultures in children are not available. The aim of this article is to describe the correlation between blood culture (BC) rates and laboratory-confirmed bloodstream infection (LCBSI) rates, on different paediatric wards of a tertiary-care centre in Germany.

METHODS

We conducted a retrospective cohort study in a paediatric university hospital, from 1st January to 31st December 2018. All blood cultures collected from neonatal (NICU) and paediatric intensive-care units (PICU), haematology/oncology, and general paediatric wards were included. There were no exclusion criteria. BC taken/1000 patients-days (BC rates/BCR) and LCBSI/1000 patient-days at risk (LCBSI rates) were calculated for each unit.

RESULTS

A total of 6040 patients were admitted to the hospital with 3114 of them into wards studied. Of the 3072 BCs collected, 200 (6.5%) were positive. Collection of BCs was performed in 51/77 (66.2%) of admitted patients on NICU, in 151/399 (37.8%) of PICU patients, in 163/755 (21.6%) of haematology/oncology patients, and in 281/1883 (14.9%) of children on general paediatric wards. Gram-positive bacteria were the most commonly detected organisms in blood cultures from all wards with exception of NICU. The BCR in NICU, PICU, haematology/oncology wards, and general wards were 61.6, 196.2, 358.4, and 52.3, respectively. Excluding commensal pathogens and possible contaminations, the LCBSI rates in the same units were 2.4, 5.6, 4.4, and 1.0, respectively.

CONCLUSION

We found different BCR values according the ward studied, being higher in patients with high risk of bloodstream infection such as haematology/oncology patients.

Reporting and Categorization of Blood Culture Contaminants in Infants and Young Children: A Scoping Review

BACKGROUND

Blood cultures are obtained routinely for infants and young children for the evaluation for serious bacterial infection. Isolation of organisms that represent possible contaminants poses a management challenge. The prevalence of bacteremia reported in this population is potentially biased by inconsistent contaminant categorization reported in the literature. Our aim was to systematically review the definition and reporting of contaminants within the literature regarding infant bacteremia.

METHODS

A search of studies published between 1986 and mid-September 2016 was conducted using Medline/PubMed. Included studies examined children aged 0 to 36 months for whom blood culture was performed as part of a serious bacterial infection evaluation. Studies that involved children in an intensive care unit, prematurely born children, and immunocompromised children or those with an indwelling catheter/device were excluded. Data extracted included contaminant designation methodology, organisms classified as contaminants and pathogens, and contamination and bacteremia rates.

DISCUSSION

Our search yielded 1335 articles, and 69 of them met our inclusion criteria. The methodology used to define contaminants was described in 37 (54%) study reports, and 16 (23%) reported contamination rates, which ranged from 0.5% to 22.8%. Studies defined contaminants according to organism species (n = 22), according to the patient's clinical management (n = 4), and using multifactorial approaches (n = 11). Many common organisms, particularly Gram-positive cocci, were inconsistently categorized as pathogens or contaminants.

CONCLUSIONS

Reporting and categorization of blood culture contamination are inconsistent within the pediatric bacteremia literature, which limits our ability to estimate the prevalence of bacteremia. Although contaminants are characterized most frequently according to organism, we found inconsistency regarding the classification of certain common organisms. A standardized approach to contaminant reporting is needed.

Histological chorioamnionitis is predicted by early infant C-reactive protein in preterm infants and correlates with neonatal outcomes

AIM

Histological chorioamnionitis (HCA) is associated with preterm birth and adverse neonatal outcomes. We evaluated the rise in C-reactive protein (CRP) in preterm infants as a predictor of HCA severity and outcomes.

METHODS

Consecutive preterm infants, born January 2009 to January 2014 in the National Maternity Hospital, Dublin, under 32 weeks' gestation or <1.5 kg birthweight, were included. Histological chorioamnionitis was staged as maternal inflammatory response, foetal inflammatory response and non-HCA.

RESULTS

Preterm infants (n = 518) were included with a mean gestational age 28.5 ± 2.8 weeks, birthweight 1.1 ± 0.3 kg, and 53.5% were male. Histological chorioamnionitis was found in 25.4%. Histological chorioamnionitis was present in 93.7% when CRP > 5 mg/L, 65.2% when CRP 1-5 mg/L and in 19.4% when CRP < 1 mg/L. When both the immature to total neutrophil (IT) ratio was >0.2 and the CRP > 1 mg/L the positive predictive value and negative predictive value for HCA were 92.5% and 84.9%, respectively. Histological chorioamnionitis was associated with more resuscitation and respiratory distress syndrome (both P < .001). A CRP > 10 mg/L was associated with a foetal inflammatory response and increased early-onset sepsis.

CONCLUSION

Higher early CRP was a surrogate predictor of HCA and correlated with the severity of HCA. Higher CRP and HCA were associated with adverse early outcomes.

Neonatal Outcomes Following Culture-negative Late-onset Sepsis Among Preterm Infants

BACKGROUND

Culture-negative late-onset sepsis (LOS) is commonly diagnosed in neonatal intensive care units, while the outcomes of neonatal culture-negative LOS are not reported for large cohorts. This study aimed to examine the incidence and neonatal outcomes for culture-negative LOS in a contemporary multicenter cohort of preterm infants.

METHODS

We performed a retrospective analysis of data from a cluster-randomized controlled study. Infants <34 weeks of gestation and admitted to 25 neonatal intensive care units between May 1, 2015, and April 30, 2018, were included. Culture-negative LOS was diagnosed if infants had abnormal manifestations and laboratory tests but negative blood cultures. The primary outcome was a composite of mortality or morbidities including periventricular leukomalacia (PVL), retinopathy of prematurity (ROP) ≥ stage 3 or bronchopulmonary dysplasia (BPD).

RESULTS

Of 22,346 eligible infants, 1505 (6.7%) infants had culture-negative and 761 (3.4%) infants had culture-positive LOS. Compared with infants without LOS, infants with culture-negative LOS had higher rates of composite outcome (24.1% vs. 9.6%), death (3.8% vs. 1.8%), PVL (4.8% vs. 2.2%), severe ROP (3.3% vs. 1.1%) and BPD (18.1% vs. 7.0%). After adjustment, culture-negative LOS was independently associated with increased risk of composite outcome {adjusted odds ratio [aOR]: 1.8 [95% confidence interval (CI): 1.5-2.1]}, PVL [aOR: 2.0 (95% CI: 1.4-2.8)] and BPD [aOR: 1.8 (95% CI: 1.5-2.2)] relative to the absence of LOS.

CONCLUSION

Culture-negative LOS was frequently diagnosed in preterm infants and was associated with increased risks of adverse outcomes. There is an emerging need for more precise diagnosis and treatment strategies for culture-negative LOS.

Biomarker-guided antibiotic stewardship in suspected ventilator-associated pneumonia (VAPrapid2): a randomised controlled trial and process evaluation

BACKGROUND

Ventilator-associated pneumonia is the most common intensive care unit (ICU)-acquired infection, yet accurate diagnosis remains difficult, leading to overuse of antibiotics. Low concentrations of IL-1β and IL-8 in bronchoalveolar lavage fluid have been validated as effective markers for exclusion of ventilator-associated pneumonia. The VAPrapid2 trial aimed to determine whether measurement of bronchoalveolar lavage fluid IL-1β and IL-8 could effectively and safely improve antibiotic stewardship in patients with clinically suspected ventilator-associated pneumonia.

METHODS

VAPrapid2 was a multicentre, randomised controlled trial in patients admitted to 24 ICUs from 17 National Health Service hospital trusts across England, Scotland, and Northern Ireland. Patients were screened for eligibility and included if they were 18 years or older, intubated and mechanically ventilated for at least 48 h, and had suspected ventilator-associated pneumonia. Patients were randomly assigned (1:1) to biomarker-guided recommendation on antibiotics (intervention group) or routine use of antibiotics (control group) using a web-based randomisation service hosted by Newcastle Clinical Trials Unit. Patients were randomised using randomly permuted blocks of size four and six and stratified by site, with allocation concealment. Clinicians were masked to patient assignment for an initial period until biomarker results were reported. Bronchoalveolar lavage was done in all patients, with concentrations of IL-1β and IL-8 rapidly determined in bronchoalveolar lavage fluid from patients randomised to the biomarker-based antibiotic recommendation group. If concentrations were below a previously validated cutoff, clinicians were advised that ventilator-associated pneumonia was unlikely and to consider discontinuing antibiotics. Patients in the routine use of antibiotics group received antibiotics according to usual practice at sites. Microbiology was done on bronchoalveolar lavage fluid from all patients and ventilator-associated pneumonia was confirmed by at least 104 colony forming units per mL of bronchoalveolar lavage fluid. The primary outcome was the distribution of antibiotic-free days in the 7 days following bronchoalveolar lavage. Data were analysed on an intention-to-treat basis, with an additional per-protocol analysis that excluded patients randomly assigned to the intervention group who defaulted to routine use of antibiotics because of failure to return an adequate biomarker result. An embedded process evaluation assessed factors influencing trial adoption, recruitment, and decision making. This study is registered with ISRCTN, ISRCTN65937227, and ClinicalTrials.gov, NCT01972425.

FINDINGS

Between Nov 6, 2013, and Sept 13, 2016, 360 patients were screened for inclusion in the study. 146 patients were ineligible, leaving 214 who were recruited to the study. Four patients were excluded before randomisation, meaning that 210 patients were randomly assigned to biomarker-guided recommendation on antibiotics (n=104) or routine use of antibiotics (n=106). One patient in the biomarker-guided recommendation group was withdrawn by the clinical team before bronchoscopy and so was excluded from the intention-to-treat analysis. We found no significant difference in the primary outcome of the distribution of antibiotic-free days in the 7 days following bronchoalveolar lavage in the intention-to-treat analysis (p=0·58). Bronchoalveolar lavage was associated with a small and transient increase in oxygen requirements. Established prescribing practices, reluctance for bronchoalveolar lavage, and dependence on a chain of trial-related procedures emerged as factors that impaired trial processes.

INTERPRETATION

Antibiotic use remains high in patients with suspected ventilator-associated pneumonia. Antibiotic stewardship was not improved by a rapid, highly sensitive rule-out test. Prescribing culture, rather than poor test performance, might explain this absence of effect.

FUNDING

UK Department of Health and the Wellcome Trust.

Two Blood Cultures With Age-Appropriate Volume Enhance Suspected Sepsis Decision-Making

Background

Multiple blood cultures have been shown to improve pathogen yield and antimicrobial stewardship for adult patients with suspected serious bacterial infection (SBI). For children, the use of multiple blood cultures is less common and volume recommendations are more complicated, often resulting in single cultures with low volume.

Methods

In 2010, Children’s Hospital Colorado instituted electronic medical record (EMR) decision support to recommend collection of 2 blood cultures before administration of antibiotics for suspected SBI. Recommended blood culture volumes were calculated by age rather than weight. We evaluated all children admitted to inpatient units between 2008 and 2009 (pre-intervention) and 2011 and 2013 (postintervention) who received antibiotics in the hospital after having blood cultures drawn in the emergency department, excluding those with a length of stay >8 days. We compared blood culture yield, isolate classification (pathogen vs contaminant), and antimicrobial modifications before and after the interventions.

Results

A total of 3948 children were included in the study. EMR guidelines were associated with a significantly higher number of children with multiple blood cultures drawn before antibiotic administration (88.0% vs 12.3%; P < .001) and an increased percentage of blood cultures with the recommended volume (74.3% vs 15.2%; P < .001), resulting in a significantly higher pathogen isolation rate and improved antimicrobial decisions. Multiple cultures helped define the role of common contaminants in the clinical decision process.

Conclusions

Multiple blood cultures with age-based volumes taken before starting antibiotics increase pathogen isolation rates and appropriate modification of antimicrobial treatment in children.

Verification of blood volume for blood culture and detection rate in pediatrics

PURPOSE

This study was conducted to estimate the blood culture volume that should be collected from pediatric patients to improve diagnostic abilities.

METHODS

Blood cultures from neonates and children aged up to 18 years were collected and the volume was measured for over a 1-year period. During the intervention period, examiners were instructed to draw 3 mL of blood for culture, if possible. The pre-intervention period was from June 1 to August 31, 2016. The post-intervention period was from September 1, 2016, to May 30, 2017. The rate of positive detections was calculated and compared between pre and post-intervention periods.

RESULTS

We collected 1352 samples and measured 1327 bottles. During the pre-intervention period, 340 cases were collected with a median blood volume of 1.64 mL; 9 cases (2.7%) were true-positive. During the intervention period, 1012 cases were ordered with a median blood volume of 2.41 mL; 19 cases (1.9%) were true-positive. After intervention, blood volume was increased significantly (p < 0.01). However, there was no significant difference in the rate of positive detections during the study periods (p = 0.254).

CONCLUSIONS

In the pediatric clinical setting in a Japanese municipal hospital, the positive detection rate did not improve even when the collected blood volume was increased. One milliliter of blood volume may be adequate for the pediatric bottle in children.

Antibiotic prescribing practices in paediatric septic shock in a tertiary care hospital in a resource limited setting: an audit

Introduction

Early empiric broad spectrum antibiotic administration in children with septic shock improves outcome. Knowledge on possible bacterial aetiology, drug resistance pattern and rational choice of antibiotics is crucial in management of septic shock.

Methods

This was an audit carried out among 50 (0- 5 years age) children admitted with septic shock at the Kenyatta National Hospital between October to December 2016. A standard questionnaire was used for data collection as per the Surviving Sepsis Guideline. Data were stored in Excel and analyzed in Strata 12.

Results

Of the 50 admitted children with septic shock 86% were less than one-year age. Samples for blood cultures were removed from 12(24%) prior to administration of antibiotics. Blood culture bottles were unavailable in 80%. All children received antibiotics. Antibiotics were initiated in 44(88%) in the golden hour of diagnosis of septic shock. Monotherapy with cephalosporins 30 (60%) was the commonest choice of initial antibiotic. Antibiotics were changed in 7(22.6%) and 1(5.3%) at 24 and 48 hours respectively due to clinical deterioration. Over mortality at 72 hours was 35 (70%). All the 9 children initiated on meropenem monotherapy on admission died.

Conclusion

The majority of patients with septic shock were under one-year age. All patients were initiated on antibiotics. Blood cultures were done in a quarter of the patients. Monotherapy with cephalosporin was the commonest choice of antibiotic. De-escalation was not well accomplished due to microbiological culture limitation. There was no standard antibiotic choice hence antibiotic use in septic shock needs to be included in the paediatric local guidelines.

Comparison of initial and final diagnoses in children with acute febrile illness: A retrospective, descriptive study: Initial and final diagnoses in children with acute fever

BACKGROUND

This study aimed to elucidate the etiologies and diagnostic errors of early-phase pediatric fever without an obvious cause.

METHODS

This single-center, retrospective, descriptive study included 1334 febrile children hospitalized at Beppu Medical Center in Japan between 2014 and 2018. Eligibility criteria were age ≤12 years, axillary temperature ≥38.0°C, and fever duration ≤7 days at admission. Initial diagnoses on the day of admission and final diagnoses at defervescence were divided into initial fever with identified source (FIS) and initial fever without source (FWS) and final FIS and final FWS, respectively. The etiology of initial FWS and diagnostic discordance between initial FIS and final FIS were investigated.

RESULTS

Of the 1334 participants, 94 (7.0%) were diagnosed with initial FWS. Among patients with initial FWS, final diagnoses were confirmed in 40 (43%), including Kawasaki disease in 17, urinary tract infection in 5, bacteremia in 4, exanthem subitum in 3, and the others in 11. Among the 1275 patients diagnosed with final FIS, diagnostic discordances between initial and final diagnoses were observed in 131 patients (10%). The multiple logistic regression analysis identified increased serum C-reactive protein value at admission (odds ratio [OR]: 1.09; 95% confidence interval [CI]: 1.06-1.13), exanthem subitum (OR: 409; 95% CI: 119-1399), and Kawasaki disease (OR: 14.3; 95% CI: 8.7-23.3) as independent risk factors for diagnostic discordance.

CONCLUSION

Exanthem subitum and Kawasaki disease may be undiagnosed or misdiagnosed in febrile children with fever duration ≤7 days.

The correct blood volume for paediatric blood cultures: a conundrum?

BACKGROUND

Bloodstream infections (BSIs) are a major cause of morbidity and mortality in paediatric patients. For fast and accurate diagnosis, blood culture (BC) is the reference standard. However, the procedure for blood sampling in paediatric patients, particularly the optimal blood volume, is the subject of controversy stemming from a lack of knowledge of the bacterial load and because of several obstacles such as low intravascular volume and the risk of causing anaemia.

AIMS

The aim of this narrative review is to summarize current knowledge on blood sampling in paediatric patients for BC purposes, in particular blood volume and number and type of BC bottles needed for reasonable future guidelines/recommendations.

SOURCES

A comprehensive literature search of PubMed, including all publications in English, was performed in June 2019 using the search terms 'blood culture', 'blood volume', 'bloodstream infection', 'diagnostic', 'paediatric' and/or 'sepsis'.

CONTENT

The amount of inoculated blood determines the sensitivity, specificity and time to positivity of a BC, and low-level bacteraemia (≤10 cfu/mL) in paediatric patients is presumed to be more common than reported. Current approaches for 'adequate' blood volume for paediatric BC are mainly weight- or age-dependent. Of these recommendations, the scheme devised by Gaur and colleagues seems most appropriate and calls for a sample of 1-1.5 mL for children weighing <11 kg and 7.5 mL for a patient weight of 11-17 kg to be drawn into one BC bottle. Inclusion of a more detailed grading in the weight range 4-14 kg, as published by Gonsalves and colleagues, might be useful.

IMPLICATIONS

This review could be important for future guidelines on paediatric BC collection and thus could contribute to improving patient management and lowering the economic and global health burden associated with BSI. Furthermore, upcoming molecular-based approaches with low sample volumes might be an interesting alternative.

Unfinished agenda of the neonates in developing countries: magnitude of neonatal sepsis: systematic review and meta-analysis

Purpose

Neonatal sepsis is the major cause of mortality and morbidity globally, particularly in developing countries. Despite studies revealed the extent of neonatal sepsis in developing countries, the findings were inconclusive. Therefore, the main aim of this study was to determine the pooled prevalence of neonatal sepsis in developing countries.

Methods

We used a systematic review and Meta-analysis study method. The reviewed studies were accessed through an electronic web-based search strategy from the electronic database (PUBMED), advanced google scholar, different journal sites. The data extraction was done by two researchers using a data extraction table and the disparity between data extractors was resolved by the third researcher. The analysis was done using STATA version 11. The I2 test was used to assess heterogeneity across studies. The Funnel plot, Begg's test, and Egger's test were used to check for publication bias. The random-effect model was used to determine the pooled effect size. All studies related to neonatal sepsis which fulfill the inclusion criteria were considered into this study. The quality of each study was checked using the Newcastle-Ottawa Scale and studies graded low score were excluded from the study.

Results

At the end, 36 articles fit with our study objectives. Studies conducted in Ethiopia were significant the source of heterogeneity of the study with a coefficient = 90, P-value = 0.025. The overall pooled prevalence of the study was 29.92%. The limitations of this study would be the authors were only used articles reported in the English language, and publication bias.

Conclusion

The pooled prevalence of neonatal sepsis was found to be high which accounted for a third of the neonates. Despite countries have established possible prevention and treatment mechanisms, neonatal sepsis is the major public health problem in lower and middle-income countries till now.

Diagnostic accuracy of serum (1,3)-beta-d-glucan for neonatal invasive candidiasis: systematic review and meta-analysis

OBJECTIVES

Neonatal invasive candidiasis (NIC) is a leading cause of infection-related morbidity and mortality in preterm neonates. Several studies have shown that (1,3)-Beta-d-glucan (BDG) was accurate in detecting invasive fungal infection in adults, but studies in neonates are scarce. The aim was to obtain summary estimates of the accuracy of BDG detection in serum for the diagnosis of NIC.

METHODS

We searched Medline, Embase, Clinicaltrials.gov, and Google Scholar (inception to July 2019). We checked the reference lists of included studies, clinical guidelines, and review articles. We included studies that assessed the accuracy of BDG against a reference standard that defined groups of patients with ordinal levels of NIC probability (e.g. proven, probable, possible) and included fungal blood culture. Participants were neonates suspected of having NIC. The intervention was BDG measurement in serum (Fungitell® assay). We assessed risk of bias and applicability using QUADAS-2. We used bivariate meta-analysis to produce summary estimates of diagnostic accuracy at prespecified positivity thresholds of 80 and 120 pg/mL. This study was registered with PROSPERO (CRD42018089545).

RESULTS

We included eight studies (465 participants). Of these, two were judged at low overall risk of bias. There was substantial variability across studies in the reference standards used. At a positivity threshold of 80 pg/mL, summary estimates of sensitivity and specificity of BDG were 89% (95% CI: 80-94%) and 60% (53-66%), respectively; summary sensitivity for detecting proven cases of NIC was 99% (93-100%). At a positivity threshold of 120 pg/mL, summary estimates of sensitivity and specificity were 81% (71-88%) and 80% (67-88%), respectively.

CONCLUSIONS

Because of high sensitivity, BDG seems promising to rule-out NIC. It might be too early to recommend its use because of the scarcity of reliable clinical data, heterogeneity in case definitions, and unstable accuracy estimates.

Rapid diagnosis of bacterial meningitis by nanopore 16S amplicon sequencing: A pilot study

Early administration of antibiotics is crucial in the management of bacterial meningitis. Rapid pathogen identification helps to make a definite diagnosis of bacterial meningitis and enables tailored antibiotic treatment. We investigated if the 16S amplicon sequencing performed by MinION, a nanopore sequencer, was capable of rapid pathogen identification in bacterial meningitis. Six retrospective cases of confirmed bacterial meningitis and two prospective cases were included. The initial cerebrospinal fluid (CSF) samples of these patients were used for the experiments. DNA was extracted from the CSF, and PCR was performed on the 16S ribosomal DNA (16S rDNA). Sequencing libraries were prepared using the PCR products, and MinION sequencing was performed for up to 3 h. The reads were aligned to the bacterial database, and the results were compared to the conventional culture studies. Pathogenic bacteria were successfully detected from the CSF by 16S sequencing in all retrospective cases. 16S amplicon sequencing was more sensitive than conventional diagnostic tests and worked properly even in antibiotics-treated samples. MinION sequencing significantly reduced the turnaround time, and even 10 min of sequencing was sufficient for pathogen detection in certain cases. Protocol adjustment could further increase the sensitivity and reduce the turnaround time for MinION sequencing. Finally, the prospective application of MinION 16S sequencing was successful. Nanopore 16S amplicon sequencing is capable of rapid bacterial identification from the CSF of the bacterial meningitis patients. It may have many advantages over conventional diagnostic tests and should therefore be applied in a larger number of patients in the future.

Critical factors in the recovery of pathogenic microorganisms in blood

BACKGROUND

The critical factors for optimal recovery of microbial pathogens from blood are not only the basis for how we perform blood cultures on a daily basis, but are also important for development of all current blood-culture systems. Because much of this research was conducted and published between 1975 and 2010 there is a general sense that many physicians and scientists may not be familiar with it, but it is critical for performing and interpreting blood cultures.

OBJECTIVES

To review the critical factors in the laboratory recovery and isolation of pathogenic microorganisms in blood.

SOURCES

Literature review of published papers, select reviews and updated guidelines.

CONTENT

This review focuses on the critical factors that affect the recovery isolation of pathogenic microorganisms from individuals with bloodstream infections. Contemporary blood-culture systems, and current methods for blood-culture collection, have been designed to incorporate these critical factors so as to optimize recovery and isolation of pathogens while minimizing contamination.

IMPLICATIONS

It is important for microbiologists and practitioners to understand how and why these critical factors affect current blood-culture practices to improve patient management. Future research should emphasize which of these critical factors will still play a role in the era of molecular diagnostic tests, which will no longer be relevant, and which new critical factors have yet to be defined.

Continuous Monitoring and Feedback Optimizes Blood Volume Inoculated Into Culture Bottles in the Pediatric Intensive Care Unit

In this quasi-experimental study that included 3489 blood culture bottles, interventions that included the distribution of simple weight-stratified guidelines for recommended blood volume and monthly feedback to physicians were effective in optimizing blood volume for culture in a pediatric intensive care unit.

Managing Infants Exposed to Maternal Chorioamnionitis by the Use of Early-Onset Sepsis Calculator

Objective. To reduce neonatal intensive care unit admission rate (NAR) and antibiotic utilization rate (AUR) in ≥36 weeks gestational age infants exposed to maternal chorioamnionitis (MC) through the application of early-onset sepsis calculator (EOSCAL). Study Design. This is a single-center cohort study. All infants born ≥36 weeks gestational age and exposed to MC were compared for NAR, AUR, and laboratory evaluation rate (LER) 2 years after and 1 year before the implementation of EOSCAL. Results. There is a significant decrease in NAR (P < .001), AUR (P < .04), and LER for blood culture, complete blood count, and C-reactive protein (P < .001) after implementation of EOSCAL. If infants received antibiotics, it was for significantly less number of doses (P < .01). There was no increase in the readmission rate. Conclusion. Use of EOSCAL significantly decreases the rate of NAR, AUR, and LER in infants exposed to MC, without affecting readmission rates and late antibiotic use.