Use of C-reactive protein to guide duration of empiric antibiotic therapy in suspected early neonatal sepsis

Ten- vs. 14-day antibiotic therapy for culture-positive neonatal sepsis

BACKGROUND

Neonatal sepsis is a major determinant of neonatal mortality. There is a scarcity of evidence-based guidelines for the duration of antibiotics in culture-positive sepsis.

OBJECTIVES

The aim of this study was to compare the efficacy of 10- and 14-day antibiotic therapies in the management of culture-positive neonatal sepsis.

METHODS

This randomized controlled trial was conducted in the neonatal intensive care unit of a tertiary care center among the neonates suffering from culture-positive sepsis (with signs of clinical remission on day 9 of antibiotic) between January 2023 and May 2023. Newborns with major congenital anomaly, deep-seated infections, multi-organ dysfunction, associated fungal infections/infection by multiple organisms and severe birth asphyxia were excluded. Two hundred and thirty-four newborns were randomized into two groups-study (received 10 days of antibiotics) and control (received 14 days of antibiotics). Treatment failure, hospital stay and adverse effects were compared between the two groups. p < 0.05 was taken as the limit of statistical significance.

RESULTS

Median [interquartile range (IQR)] birth weight and gestational age of the study population (53.8% boys) were 2.424 kg (IQR: 2.183-2.695) and 37.3 weeks (IQR: 35.5-38.1), respectively. Acinetobacter was the most commonly isolated species (56, 23.9%). The baseline characteristics of both groups were almost similar. Treatment failure was similar in the study and control groups (3.8% vs. 1.7%, p = 0.40), with a shorter hospital stay [median (IQR): 14 (13-16) vs. 18 (17-19) days, p < 0.001].

CONCLUSION

Ten-day antibiotic therapy was comparable with 14-day antibiotic therapy in efficacy, with a shorter duration of hospital stay and without any significant increase in adverse effects.

Biomarkers of Neonatal Sepsis: Where We Are and Where We Are Going

Neonatal sepsis is a bacterial bloodstream infection leading to severe clinical manifestations frequently associated with death or irreversible long-term deficits. Antibiotics are the drug of choice to treat sepsis, regardless of age. In neonates, the lack of reliable criteria for a definite diagnosis and the supposition that an early antibiotic administration could reduce sepsis development in children at risk have led to a relevant antibiotic overuse for both prevention and therapy. The availability of biomarkers of neonatal sepsis that could alert the physician to an early diagnosis of neonatal sepsis could improve the short and long-term outcomes of true sepsis cases and reduce the indiscriminate and deleterious use of preventive antibiotics. The main aim of this narrative review is to summarize the main results in this regard and to detail the accuracy of currently used biomarkers for the early diagnosis of neonatal sepsis. Literature analysis showed that, despite intense research, the diagnosis of neonatal sepsis and the conduct of antibiotic therapy cannot be at present decided on the basis of a single biomarker. Given the importance of the problem and the need to reduce the abuse of antibiotics, further studies are urgently required. However, instead of looking for new biomarkers, it seems easier and more productive to test combinations of two or more of the presently available biomarkers. Moreover, studies based on omics technologies should be strongly boosted. However, while waiting for new information, the use of the clinical scores prepared by some scientific institutions could be suggested. Based on maternal risk factors and infant clinical indicators, sepsis risk can be calculated, and a significant reduction in antibiotic consumption can be obtained.

2.5 Million Annual Deaths-Are Neonates in Low- and Middle-Income Countries Too Small to Be Seen? A Bottom-Up Overview on Neonatal Morbi-Mortality

(1) Background: Every year, 2.5 million neonates die, mostly in low- and middle-income countries (LMIC), in total disregard of their fundamental human rights. Many of these deaths are preventable. For decades, the leading causes of neonatal mortality (prematurity, perinatal hypoxia, and infection) have been known, so why does neonatal mortality fail to diminish effectively? A bottom-up understanding of neonatal morbi-mortality and neonatal rights is essential to achieve adequate progress, and so is increased visibility. (2) Methods: We performed an overview on the leading causes of neonatal morbi-mortality and analyzed the key interventions to reduce it with a bottom-up approach: from the clinician in the field to the policy maker. (3) Results and Conclusions: Overall, more than half of neonatal deaths in LMIC are avoidable through established and well-known cost-effective interventions, good quality antenatal and intrapartum care, neonatal resuscitation, thermal care, nasal CPAP, infection control and prevention, and antibiotic stewardship. Implementing these requires education and training, particularly at the bottom of the healthcare pyramid, and advocacy at the highest levels of government for health policies supporting better newborn care. Moreover, to plan and follow interventions, better-quality data are paramount. For healthcare developments and improvement, neonates must be acknowledged as humans entitled to rights and freedoms, as stipulated by international law. Most importantly, they deserve more respectful care.

Antibiotic stewardship in NICU: De-implementing routine CRP to reduce antibiotic usage in neonates at risk for early-onset sepsis

OBJECTIVE

Antibiotic overuse is common in the neonatal intensive care units (NICUs). We evaluated the change in antibiotic utilization rate (AUR) by eliminating routine CRP in the management of early-onset sepsis (EOS).

METHODS

Retrospective before-after cohort study in a Level 3B NICU. We made the following practice changes in the management of EOS: (1) stop routine CRP and (2) implement an automatic stop order (ASO) for antibiotics at 48 h. We compared the AUR, defined as any antibiotic use per 1000 patient days before and after practice change.

RESULT

There was an absolute reduction of 30% in AUR and a decrease in the proportion of neonates receiving antibiotics from the day of life 3-6 in postintervention period. We did not identify any case of partially treated EOS with change in practice.

CONCLUSION

Elimination of routine CRP and ASO implementation for antibiotics in neonates at risk for EOS decreased AUR.

Clinical characterization of benign enterovirus infection in neonates

Enteroviruses is a group of positive single-stranded RNA viruses ubiquitous in the environment, which is a causative agent of epidemic diseases in children and infants. But data on neonates are still limited. The present study aimed to describe the clinical characteristics of enterovirus infection in neonates and arise the awareness of this disease to general public.Between March 2018 and September 2019, data from all of the neonates diagnosed with enterovirus infection were collected and analyzed from neonatal intensive care unit of Zhangzhou Hospital in Fujian, China.A total of 23 neonates were enrolled. All of them presented with fever (100%), and some with rashes (39.1%). The incidence of aseptic meningitis was high (91.3%), but only a small proportion (28.6%) presented with cerebrospinal fluid (CSF) leukocytosis. The positive value for nucleic acid detection in CSF was significantly higher than throat swab (91.3% vs 43.5%, P = .007). Five of the infected neonates presented with aseptic meningitis (23.8%) underwent brain magnetic resonance imaging examination and no craniocerebral injuries were found. Subsequent follow-ups were performed in 15 of them (71.4%) and no neurological sequelae was found.Aseptic meningitis is a common type of enterovirus infection in neonates with a benign course. Nucleic acid detection of CSF has an important diagnostic value. Febrile neonates would be suggested to screen for enterovirus infection in addition to complete septic workup. An unnecessary initiation or earlier cessation of antibiotics could be considered in enterovirus infection, but that indications still need further studies to guarantee the safety.

Aetiology of invasive bacterial infection and antimicrobial resistance in neonates in sub-Saharan Africa: a systematic review and meta-analysis in line with the STROBE-NI reporting guidelines

BACKGROUND

Aetiological data for neonatal infections are essential to inform policies and programme strategies, but such data are scarce from sub-Saharan Africa. We therefore completed a systematic review and meta-analysis of available data from the African continent since 1980, with a focus on regional differences in aetiology and antimicrobial resistance (AMR) in the past decade (2008-18).

METHODS

We included data for microbiologically confirmed invasive bacterial infection including meningitis and AMR among neonates in sub-Saharan Africa and assessed the quality of scientific reporting according to Strengthening the Reporting of Observational Studies in Epidemiology for Newborn Infection (STROBE-NI) checklist. We calculated pooled proportions for reported bacterial isolates and AMR.

FINDINGS

We included 151 studies comprising data from 84 534 neonates from 26 countries, almost all of which were hospital-based. Of the 82 studies published between 2008 and 2018, insufficient details were reported regarding most STROBE-NI items. Regarding culture positive bacteraemia or sepsis, Staphylococcus aureus, Klebsiella spp, and Escherichia coli accounted for 25% (95% CI 21-29), 21% (16-27), and 10% (8-10) respectively. For meningitis, the predominant identified causes were group B streptococcus 25% (16-33), Streptococcus pneumoniae 17% (9-6), and S aureus 12% (3-25). Resistance to WHO recommended β-lactams was reported in 614 (68%) of 904 cases and resistance to aminoglycosides in 317 (27%) of 1176 cases.

INTERPRETATION

Hospital-acquired neonatal infections and AMR are a major burden in Africa. More population-based neonatal infection studies and improved routine surveillance are needed to improve clinical care, plan health systems approaches, and address AMR. Future studies should be reported according to standardised reporting guidelines, such as STROBE-NI, to aid comparability and reduce research waste.

FUNDING

Uduak Okomo was supported by a Medical Research Council PhD Studentship.

Biomarker-guided antibiotic cessation in sepsis: evidence and future challenges

Sepsis is a medical emergency, which requires the initiation of broad-spectrum antimicrobial agents as early as possible. In the absence of positive microbiological cultures providing targeted antimicrobial advice, broad-spectrum antibiotics are commonly continued until there is clinical evidence of infection resolution. With an absence of robust evidence to inform when it is safe to stop antimicrobial agents in sepsis, the duration of antimicrobial courses may be longer than is required. Prolonged courses of potent broad-spectrum antimicrobials increase the risk of adverse drug events and contribute to the growing emergence of multidrug resistant pathogens, which is a global public health emergency. The protocolised use of protein biomarkers to guide clinical decision making can be used to help combat excessive durations of antimicrobials in patients with sepsis. This article reviews the current evidence for biomarker-guided antimicrobial discontinuation protocols in sepsis, identifies related evidence gaps and examines future innovation challenges in this field.

How to use C-reactive protein

A 3-month-old baby is brought to the paediatric emergency department by their parents because of a fever. You decide to check their inflammatory markers. Their C-reactive protein (CRP) level comes back as 20 mg/L. Does this affect whether or not you start antibiotic therapy? Does it influence your decision to admit or discharge the patient? CRP is a commonly used biochemical test and yet its use is constantly debated and challenged. We look at the current evidence and suggest the best way to use this test in clinical practice.

Biomarker-guided antibiotic therapy-strengths and limitations

Biomarkers as C-reactive protein (CRP) and procalcitonin (PCT) emerged as tools to help clinicians to diagnose infection and to properly initiate and define the duration of antibiotic therapy. Several randomized controlled trials, including adult critically ill patients, showed that PCT-guided antibiotic stewardship was repeatedly associated with a decrease in the duration of antibiotic therapy with no apparent harm. There are however some relevant limitations in these trials namely the low rate of compliance of PCT-guided algorithms, the high rate of exclusion (without including common clinical situations and pathogens) and the long duration of antibiotic therapy in control groups. Such limitations weakened the real impact of such algorithms in the clinical decision-making process and strengthened the concept that the initiation and the duration of antibiotic therapy cannot depend solely on a biomarker. Future efforts should address these limitations in order to better clarify the role of biomarkers on the complex and multifactorial issue of antibiotic management and to deeply understand its potential effect on mortality.

The role of infection models and PK/PD modelling for optimising care of critically ill patients with severe infections

Critically ill patients with severe infections are at high risk of suboptimal antimicrobial dosing. The pharmacokinetics (PK) and pharmacodynamics (PD) of antimicrobials in these patients differ significantly from the patient groups from whose data the conventional dosing regimens were developed. Use of such regimens often results in inadequate antimicrobial concentrations at the site of infection and is associated with poor patient outcomes. In this article, we describe the potential of in vitro and in vivo infection models, clinical pharmacokinetic data and pharmacokinetic/pharmacodynamic models to guide the design of more effective antimicrobial dosing regimens. Individualised dosing, based on population PK models and patient factors (e.g. renal function and weight) known to influence antimicrobial PK, increases the probability of achieving therapeutic drug exposures while at the same time avoiding toxic concentrations. When therapeutic drug monitoring (TDM) is applied, early dose adaptation to the needs of the individual patient is possible. TDM is likely to be of particular importance for infected critically ill patients, where profound PK changes are present and prompt appropriate antibiotic therapy is crucial. In the light of the continued high mortality rates in critically ill patients with severe infections, a paradigm shift to refined dosing strategies for antimicrobials is warranted to enhance the probability of achieving drug concentrations that increase the likelihood of clinical success.

Serial C reactive protein values predict sensitivity of organisms to empirical antibiotics in neonates: a nested case-control study

BACKGROUND

It is common clinical practice to repeat serum C reactive protein (CRP) estimation in the first 48 h after starting empirical antibiotics for neonatal sepsis. The change in CRP is believed to indicate whether the empirical antibiotics are appropriate or not, but there is little evidence to support this practice.

METHODS

This was a nested case-control study on neonates with suspected sepsis (clinical signs+baseline CRP >10 mg/L). We drew samples for serum CRP at baseline and at 24, 36 and 48 h after starting empirical antibiotics and stored them at -20°C. Those with positive blood cultures were enrolled into two groups: those who had received empirical antibiotics to which the organism was sensitive ('sensitive') and those who had received antibiotics to which the organism was resistant ('resistant'). Stored samples of these subjects were assayed for CRP. Repeated CRP values were compared between groups by mixed linear models. We evaluated change in CRP from baseline as a diagnostic test for identifying empirical use of sensitive antibiotics.

RESULTS

We enrolled 45 and 44 subjects in 'sensitive' and 'resistant' groups, respectively. In the 'resistant' group, median CRP increased with time but decreased in the 'sensitive' group. Decline in CRP by 48 h identified the use of antibiotics to which the organism was sensitive with 89% sensitivity and 80% specificity.

CONCLUSIONS

Serial CRP values in the first 48 h of antibiotic therapy help to predict whether the causative organism is sensitive to the empirical antibiotics administered.

Population pharmacokinetics and pharmacodynamics of teicoplanin in neonates: making better use of C-reactive protein to deliver individualized therapy

OBJECTIVES

There is uncertainty about the optimal teicoplanin regimens for neonates. The study aim was to determine the population pharmacokinetics (PK) of teicoplanin in neonates, evaluate currently recommended regimens and explore the exposure-effect relationships.

METHODS

An open-label PK study was conducted. Neonates from 26 to 44 weeks post-menstrual age were recruited (n = 18). The teicoplanin regimen was a 16 mg/kg loading dose, followed by 8 mg/kg once daily. Therapeutic drug monitoring and dose adjustment were not conducted. A standard two-compartment PK model was developed, followed by models that incorporated weight. A PK/pharmacodynamic (PD) model with C-reactive protein serial measurements as the PD input was fitted to the data. Monte Carlo simulations (n = 5000) were performed using Pmetrics. The AUCs at steady state and the proportion of patients achieving the recommended drug exposures (i.e. Cmin >15 mg/L) were determined. The study was registered in the European Clinical Trials Database Registry (EudraCT: 2012-005738-12).

RESULTS

The PK allometric model best accounted for the observed data. The PK parameters medians were: clearance = 0.435 × (weight/70)0.75 (L/h); volume = 0.765 (L); Kcp = 1.3 (h-1); and Kpc = 0.629 (h-1). The individual time-course of C-reactive protein was well described using the Bayesian posterior estimates for each patient. The simulated median AUC96-120 was 302.3 mg·h/L and the median Cmin at 120 h was 12.9 mg/L; 38.8% of patients attained a Cmin >15 mg/L by 120 h.

CONCLUSIONS

Teicoplanin population PK is highly variable in neonates, weight being the best descriptor of PK variability. A low percentage of neonates were able to achieve Cmin >15 mg/L. The routine use of therapeutic drug monitoring and improved knowledge on the PD of teicoplanin is required.

Improving the outcome of bacterial meningitis in newborn infants in Africa: reflections on recent progress

PURPOSE OF REVIEW

There has been a reduction in overall under fives mortality (UFM) but neonatal mortality has not fallen at the same rate as for older children. Bacterial meningitis remains a common, often unrecognized and devastating illness in many African newborns with high mortality and morbidity. Further progress in reducing UFM has to focus on quality of care for neonates. Recent efforts to improve diagnosis, treatment and outcome are reviewed.

RECENT FINDINGS

Diagnosis is often unsupported by laboratory tests and efforts have been made to improve the clinical diagnosis of bacterial meningitis. Simpler, robust bedside tests are being devised. The cause of bacterial meningitis is changing and first-line antimicrobial therapy and adjuvant therapies are evaluated. Programmes to reduce risk factors and prevent neonatal infections are identified.

SUMMARY

Neonatal care needs to improve in first referral hospitals with simple, low-cost, validated measures provided as bundles of care for both mother and child. First-line antibiotic therapy must be reconsidered in the light of increased infections by multiresistant and Gram-negative bacteria. Studies are needed for effective and safe lengths of antimicrobial therapy, the role of adjuvant therapy and the best anticonvulsants to use.

Markedly raised levels of C-reactive protein are associated with culture-proven sepsis or necrotising enterocolitis in extremely preterm neonates

AIM

A serious inflammatory process is suspected when C-reactive protein (CRP) is very high, and we established the causes and outcomes when CRP was >100 mg/L in neonates.

METHODS

We retrospectively reviewed all 277 episodes where CRP exceeded 100 mg/L between January 2007 and December 2011 at a tertiary neonatal unit.

RESULTS

Of the 6025 neonates admitted during the study period, 258 had CRP >100 mg/L at least once. The overall mortality rate was 44/258 (17%); 36 died within 7 days of CRP >100 mg/L, and 34 were extremely preterm infants. CRP exceeded 100 mg/L in 106 infants within the first 3 days of life - 74 term, 25 preterm and seven extremely preterm - with no infection identified in 81%. In contrast, infections were found in 87% of the 171 episodes from day four of life - 129 extremely preterm, 23 preterm and 19 term - predominantly coagulase-negative staphylococcus sepsis and necrotising enterocolitis.

CONCLUSION

Markedly elevated CRP in the first 3 days of life was most likely to affect term neonates (74/106) with no infectious cause (81%). However, CRP >100 mg/L from the fourth day of life was most likely to affect extremely preterm neonates (129/171) and have an infectious cause (87%).

Management of neonatal sepsis at Muhimbili National Hospital in Dar es Salaam: diagnostic accuracy of C-reactive protein and newborn scale of sepsis and antimicrobial resistance pattern of etiological bacteria

Background

We determined the accuracy of Rubarth’s newborn scale of sepsis and C- reactive protein in diagnosing neonatal sepsis and assessed antimicrobial susceptibility pattern of etiological bacteria.

Methods

This cross sectional study was conducted at Muhimbili National Hospital in Dar es Salaam, Tanzania between July 2012 and March 2013. Neonates suspected to have sepsis underwent physical examination using Rubarth’s newborn scale of sepsis (RNSOS). Blood was taken for culture and antimicrobial sensitivity testing, full blood picture and C – reactive protein (CRP) performed 12 hours apart. The efficacy of RNSOS and serial CRP was assessed by calculating sensitivity, specificity, negative and positive predictive values, receiver operating characteristics (ROC) analysis as well as likelihood ratios (LHR) with blood culture result used as a gold standard.

Results

Out of 208 blood samples, 19.2% had a positive blood culture. Single CRP had sensitivity and specificity of 87.5% and 70.9% respectively, while RNSOS had sensitivity of 65% and specificity of 79.7%. Serial CRP had sensitivity of 69.0% and specificity of 92.9%. Combination of CRP and RNSOS increased sensitivity to 95.6% and specificity of 56.4%. Combination of two CRP and RNSOS decreased sensitivity to 89.1% but increased specificity to 74%. ROC for CRP was 0.86; and for RNSOS was 0.81.

For CRP the LHR for positive test was 3 while for negative test was 0.18, while for RNSOS the corresponding values were 3.24 and for negative test was 0.43.

Isolated bacteria were Klebsiella spp 14 (35%), Escherichia coli 12 (22.5%), Coagulase negative staphlococci 9 (30%), Staphylococcus aureus 4 (10%), and Pseudomonas spp 1 (2.5%). The overall resistance to the WHO recommended first line antibiotics was 100%, 92% and 42% for cloxacillin, ampicillin and gentamicin, respectively. For the second line drugs resistance was 45%, 40%, and 7% for ceftriaxone, vancomycin and amikacin respectively.

Conclusions

Single CRP in combination with RNSOS can be used for rapid identification of neonates with sepsis due to high sensitivity (95.6%) but cannot exclude those without sepsis due to low specificity (56.4%). Serial CRP done 12hrs apart can be used to exclude non-cases. This study demonstrated very high levels of resistance to the first-line antibiotics.

Value of a single C-reactive protein measurement at 18 h of age

OBJECTIVE

To evaluate the usefulness of a single C-Reactive Protein (CRP) measurement at 18 h of age to identify neonates where antibiotics started for possible early onset sepsis (EOS) could safely be discontinued.

DESIGN/METHODS

In a prospective cohort of 647 preterm (<35 weeks) and 555 late preterm (35-36 weeks) or term newborns with maternal and/or neonatal risk factors for EOS, CRP levels were measured between 15 and 21 h of age.

RESULTS

There were 16, 107 and 1079 neonates with proven EOS, possible EOS and no EOS, respectively. Among the 645 neonates with a CRP<10 mg/L, 1 had proven EOS, 43 had possible EOS and 601 (93.2%) were not infected. All with possible or proven EOS were either less than 35 weeks' gestation, symptomatic at the time of CRP assessment or remained on antibiotics because of maternal bacteraemia: they would therefore not be considered for discharge. There were 557 neonates with a 18-h CRP ≥ 10 mg/L. Of these, 15 had proven EOS, 64 had possible EOS, and 478 (85.8%) were not infected. Sensitivity and specificity of 18-h CRP for proven or possible EOS were 64% (95% CI 56 to 73) and 56% (95% CI 53 to 59), respectively. The negative predictive value was 93% (95% CI 91 to 95), and the positive predictive value was 14% (95% CI 11 to 17).

CONCLUSIONS

The duration of antibiotic treatment in neonates born beyond 34 weeks' gestation and asymptomatic at the time of CRP assessment could be potentially reduced with a diagnostic algorithm that includes a point-of-care 18-h CRP measurement. An elevated 18-h CRP in isolation should not be used as a reason to prolong antibiotics.

Neonatal adrenal abscess revisited: the importance of raised inflammatory markers

Adrenal abscesses rarely occur in neonates and usually present with non-specific signs and symptoms. Prompt diagnosis requires an index of suspicion. We describe right-sided adrenal haemorrhage and abscess formation in a newborn with hypoxic-ischaemic encephalopathy following maternal post-partum haemorrhage and sepsis with Escherichia coli and Enterococcus faecalis. Percutaneous drainage of the abscess identified an E. coli isolate identical to that in the mother plus Candida albicans.

Role of biomarkers in the management of antibiotic therapy: an expert panel review: I - currently available biomarkers for clinical use in acute infections

In the context of worldwide increasing antimicrobial resistance, good antimicrobial prescribing in more needed than ever; unfortunately, information available to clinicians often are insufficient to rely on. Biomarkers might provide help for decision-making and improve antibiotic management. The purpose of this expert panel review was to examine currently available literature on the potential role of biomarkers to improve antimicrobial prescribing, by answering three questions: 1) Which are the biomarkers available for this purpose?; 2) What is their potential role in the initiation of antibiotic therapy?; and 3) What is their role in the decision to stop antibiotic therapy? To answer these questions, studies reviewed were limited to recent clinical studies (<15 years), involving a substantial number of patients (>50) and restricted to controlled trials and meta-analyses for answering questions 2 and 3. With regard to the first question concerning routinely available biomarkers, which might be useful for antibiotic management of acute infections, these are currently limited to C-reactive protein (CRP) and procalcitonin (PCT). Other promising biomarkers that may prove useful in the near future but need to undergo more extensive clinical testing include sTREM-1, suPAR, ProADM, and Presepsin. New approaches to biomarkers of infections include point-of-care testing and genomics.

Evaluating the QuikRead® C-reactive protein test as a point-of-care test

BACKGROUND

Available tests to diagnose infection in neonates often provide results after 12-24 hours. A bedside test that is reliable will facilitate earlier exclusion or diagnosis of infection.

OBJECTIVE

To validate a bedside C-reactive protein (CRP) test against the currently available laboratory CRP test in neonates with suspected sepsis.

METHODS

This was a prospective observational study where a bedside CRP was done concurrently with and validated against a laboratory CRP in neonates with suspected sepsis. The sensitivities, specificities and predictive values for the bedside CRP tests were calculated using the laboratory CRPs as the reference test.

RESULTS

There were 209 measured CRP-sample pairs. Seventy per cent of these had suspected early-onset neonatal sepsis and 30% had suspected late-onset neonatal sepsis. Twelve per cent had culture-proven sepsis. At the recommended cut-off of 8.0 mg/L for the bedside CRP test, the sensitivity, specificity, positive and negative predictive values were 84%, 80%, 30% and 97%, respectively. Adjusting the cut-off value from 8.0 to 15.0 mg/L improved the specificity to 88%. The sensitivity, specificity and positive and negative predictive values were not different between early-onset and late-onset sepsis. The receiver operating characteristic curve had an area below the curve of 0.84 for the cut-off at 16.2 mg/L on the beside CRP test.

CONCLUSIONS

The bedside CRP test may be used as a screening test to aid decisions to either commence or discontinue antibiotics in circumstances where the clinical diagnosis of sepsis is in doubt. By using a cut-off of 16.0 mg/L for the bedside CRP test, the possibility of a false negative result is minimised.

Choice and duration of antimicrobial therapy for neonatal sepsis and meningitis

Neonatal sepsis is associated with increased mortality and morbidity including neurodevelopmental impairment and prolonged hospital stay. Signs and symptoms of sepsis are nonspecific, and empiric antimicrobial therapy is promptly initiated after obtaining appropriate cultures. However, many preterm and low birth weight infants who do not have infection receive antimicrobial agents during hospital stay. Prolonged and unnecessary use of antimicrobial agents is associated with deleterious effects on the host and the environment. Traditionally, the choice of antimicrobial agents is based on the local policy, and the duration of therapy is decided by the treating physician based on clinical symptoms and blood culture results. In this paper, we discuss briefly the causative organism of neonatal sepsis in both the developed and developing countries. We review the evidence for appropriate choice of empiric antimicrobial agents and optimal duration of therapy in neonates with suspected sepsis, culture-proven sepsis, and meningitis. Moreover, there is significant similarity between the causative organisms for early- and late-onset sepsis in developing countries. The choice of antibiotic described in this paper may be more applicable in developed countries.

Time course of C-reactive protein and inflammatory mediators after neonatal surgery

OBJECTIVE

To characterize the perioperative course of C-reactive protein (CRP) and inflammatory mediators in neonates ≤44 weeks' corrected gestational age.

STUDY DESIGN

Prospective study of CRP and inflammatory mediators interleukin (IL)-1β, IL-6, IL-8, IL-10, and tumor necrosis factor-α in 55 neonates undergoing thoracic or abdominal surgery.

RESULTS

In the absence of infection, CRP increased after surgery, peaking on post-operative day 2. The perioperative patterns of CRP differed by diagnosis and inflammatory state. Surgery alone did not cause an increase in CRP because in 13 of 55 infants (24%), CRP remained <1.0 mg/dL at all time points. For thoracic procedures, patent ductus arteriosus ligation showed the least post-operative increase in CRP, and patients undergoing repair of congenital diaphragmatic hernia or tracheoesophageal fistula had a greater response. Abdominal procedures with low CRP response included repair of imperforate anus and pyloric stenosis, while gastroschisis repair and bowel reanastomosis after necrotizing enterocolitis were accompanied by a robust CRP response. IL-6 concentrations peaked on post-operative day 1 and correlated with the post-operative day 2 CRP peak (r=0.398, P=.004). The additional inflammatory mediators measured were not informative.

CONCLUSIONS

The range and time course of perioperative CRP differ by diagnosis. Serial measurements may be more informative than CRP magnitude.

A clinic-biological score for diagnosing early-onset neonatal infection in critically ill preterm infants

OBJECTIVE

To identify the best combination of serum cytokines and clinical parameters to diagnose rapidly early-onset neonatal infection (EONI) in critically ill preterm infants. At birth, most critically ill neonates are receiving broad-spectrum antibiotics pending bacterial culture results, because distinguishing infected from noninfected infants at birth is difficult.

DESIGN

Prospective study.

SETTING

Neonatal intensive care unit in a tertiary care hospital.

PATIENTS

Two hundred thirteen infants, born before 33 wks' gestation, admitted to the neonatal intensive care unit within 6 hrs of life with a presumptive diagnosis of EONI.

INTERVENTION

A presumptive diagnosis of EONI was associated with a 300-μL blood sample to measure six cytokine (interleukin [IL]-1β, IL-6, IL-8, IL-10, IL-12, tumor necrosis factor-α) concentrations, using the cytometric bead array technique.

MEASUREMENTS AND MAIN RESULTS

Of the 213 infants included, 31 had a definite or possible EONI and 182 were not infected. Concentrations of IL-6, IL-8, and IL-10 were significantly increased in infected neonates, in comparison with infants without EONI. In contrast, IL-1β, IL-12, and tumor necrosis factor-α concentrations were not. Logistic regression analyses were performed to construct multivariate predictive models that could distinguish infected from noninfected infants at birth. A clinical score was based on three parameters independently associated with EONI (i.e., interval of >12 hrs between the membranes rupture and delivery, prenatal maternal colonization and mechanical ventilation at birth). This score was compared with scores including clinical parameters and serum cytokines, alone or in combination. The best predictive model combined the three clinical parameters, IL-6 (positive threshold, 300 pg/mL) and IL-8 (positive threshold, 300 pg/mL) concentrations.

CONCLUSION

A predictive model combining serum IL-6 and IL-8 measurements and selected clinical variables could distinguish infected from noninfected preterm infants at birth and should help the clinician in reducing or shortening the unnecessary use of antibiotics.

Ten days vs. 14 days antibiotic therapy in culture-proven neonatal sepsis

BACKGROUND

There are no evidence-based guidelines for the treatment of neonatal sepsis although standard text books recommend 14 days of antibiotics for blood culture-proven neonatal sepsis.

OBJECTIVE

The present study compared the effectiveness of a 10-day course of antibiotic therapy with the conventional 14-day course in blood culture-proven neonatal sepsis.

METHODS

Infants ≥ 32 weeks and ≥ 1.5 kg weight with blood culture-proven sepsis were randomized to either 10-day (study group) or 14-day (control group) therapy on Day 7 of appropriate antibiotic therapy, if they were in clinical remission and were C-Reactive Protein (CRP) negative. The primary outcome was treatment failure within 28 days defined by either positive CRP or positive blood culture or clinical relapse.

RESULTS

The baseline characteristics were comparable between the two groups. There was one treatment failure in each group. The duration of hospital stay was significantly shorter in the 10-day treatment group.

CONCLUSION

Ten-day antibiotic therapy is as effective as 14-day therapy in blood culture-proven neonatal sepsis, if the infant has achieved clinical remission by Day 7 of therapy.

Adjunct laboratory tests in the diagnosis of early-onset neonatal sepsis

Early-onset sepsis remains a major diagnostic problem in neonatal medicine. Definitive diagnosis depends on cultures of blood or other normally sterile body fluids. Abnormal hematological counts, acute-phase reactants, and inflammatory cytokines are neither sensitive nor specific, especially at the onset of illness. Combinations of measurements improve diagnostic test performance, but the optimal selection of analytes has not been determined. The best-established use of these laboratory tests is for retrospective determination that an infant was not infected, based on failure to mount an acute-phase response over the following 24 to 48 hours.

Procalcitonin in preoperative diagnosis of abdominal sepsis

BACKGROUND AND AIMS

The present study attempted to identify the diagnostic significance of procalcitonin (PCT) in acute abdominal conditions as well as the range of concentrations relating to diagnosis of abdominal sepsis.

MATERIALS AND METHODS

This was prospective clinical study. The study included 98 consecutive patients with acute abdominal conditions, divided in sepsis and systemic inflammatory response syndrome (SIRS) group.

RESULTS

PCT concentrations on admission were significantly higher in the sepsis group than in the SIRS group (median [interquartile range] 2.32 [7.41] vs 0.45 ng/ml [2.62]). A cutoff value of 1.1 ng/ml yielded 72.4% sensitivity and 62.5% specificity. In a group of patients with abdominal symptoms lasting for more than 24 h, a cut-off value of 1.1 ng/ml yielded higher sensitivity (82.9%) and higher specificity (77.3%).

CONCLUSION

Our results suggest that PCT measurements may be useful for early, preoperative diagnosis of abdominal sepsis.

A population-based observational study of restrictive guidelines for antibiotic therapy in early-onset neonatal infections

BACKGROUND

The extensive use of broad-spectrum antibiotics has been associated with major changes in the spectrum of organisms involved in early-onset neonatal infection (EONI), their susceptibility to antibiotics, or both. Therefore, guidelines for a more rational use of antibiotics in neonates have been developed. We conducted a population-based observational study to assess the effectiveness and compliance with restrictive guidelines for the antibiotic therapy in EONI.

METHODS

Neonates receiving antibiotics within 72 hours of life were identified prospectively by population-based surveillance in the 18 hospitals of Burgundy, between February 2002 and June 2003. They were treated in accordance with guidelines limiting the use of broad-spectrum antibiotics and shortening the treatment duration. Each neonate included was evaluated for 60 days after birth. An unfavorable outcome was defined as death related to EONI or late-onset infection.

RESULTS

Of the 25,480 infants born during the study period, 1012 received antibiotics at birth. Of these 1012 infants, 39 were definitely infected (septicemia), 288 clinically infected and 685 not infected. The EONI cure rate was 96.8% without infectious relapse. Forty-five infants received a second course of antibiotic therapy. Birth weight (OR: 5.6; 95% CI: 2.2-14.1), mechanical ventilation (OR: 4.1; 95% CI: 1.3-13.1), central venous catheterization (OR: 16.1; 95% CI: 1.8-141.9), and antibiotic therapy duration (OR: 2.5; 95% CI: 1.1-5.5) were independently associated with late-onset infection.

CONCLUSION

Reducing the antibiotic therapy duration does not increase the risk of infectious relapse and may decrease the incidence of late-onset infection.

Hyperglycaemia as a possible marker of invasive fungal infection in preterm neonates

AIM

The incidence of invasive fungal infection in preterm newborns is rising steadily. Early recognition and treatment are imperative, but diagnosis is difficult as data from microbiological investigations are often poor, and clinical and laboratory signs do not help in differentiating bacterial from fungal infections. We evaluated whether glucose intolerance could represent a possible surrogate marker predictor of invasive fungal infection in preterm neonates.

METHODS

We performed a case-control study on neonates with birthweight less than 1250 g admitted to our tertiary-level unit during the years 1998-2004 (n = 383), comparing those with invasive fungal infection (n = 45, group A) to matched controls with late-onset sepsis caused by bacterial agents (n = 46, group B). We investigated in both groups the occurrence of hyperglycaemia (serum glycaemia > 215 mg/dl, i.e. 12 mmol/l) in the first month of life, and its temporal relationship with the episodes of sepsis.

RESULTS

Hyperglycaemia occurred significantly more often in group A (21/45, 46.6%) than in group B neonates (11/46, 23.9%) (OR 1.95, 95% CI 1.235-4.432, p = 0.008). Moreover, in 19 of 21 (90.4%) neonates with hyperglycaemia in group A, the carbohydrate intolerance episode typically occurred 72 h prior to the onset of invasive fungal infection; in contrast, no temporal relationship was found in neonates with bacterial sepsis (p = 0.002). Correction of hyperglycaemia was successfully achieved in all neonates of both groups, with no significant differences in the number of days of insulin treatment needed to normalize glycaemia (p = 0.15).

CONCLUSIONS

Hyperglycaemia is significantly more frequent in neonates who subsequently develop fungal rather than bacterial late-onset sepsis, with a typical 3-d interval. We suggest that a preterm neonate whose birthweight is less than 1250 g in its first month of life should be carefully evaluated for systemic fungal infection whenever signs of carbohydrate intolerance occur.

C-reactive protein and cytokines in the diagnosis of neonatal sepsis

Introduction. Accurate evaluation and correct treatment of neonates for possible sepsis still represent the most challenging clinical tasks. Early diagnosis of neonatal sepsis is largely based on the measurement of serum concentrations of different mediators of systemic inflammation, as well as, on a group of proteins named acute phase reactants. Among acute phase reactants, C-reactive protein (CRP) has been the most extensively used and investigated so far. Synthesis and biological role of CRP. This article reviews current knowledge on the synthesis, structure and biologic roles of CRP. Also, we present our original results in regard to the kinetics of serum CRP concentration during the first 24 hours of systemic infection, as well as different patterns of CRP dynamics associated with the initial choice of antibiotics, complications and the final outcome of systemic infection. Interleukins and procalcitonin in diagnosis of sepsis. Because CRP is specific, but somewhat late marker of neonatal sepsis, possible diagnostic use of other indicators of inflammation, i.e. interleukins 6 and 8, and procalcitonin during neonatal sepsis is also considered. The theoretical advantage of these early indicators is discussed in comparative analysis of the time of their activation after initial infectious stimuli. Conclusion. In conclusion, we point to the diagnostic accuracy of serial measurements of serum CRP levels. As an alternative, simultaneous measurement of CRP and serum levels using a faster marker, such as procalcitonin, is recommended.

Improved diagnostic approaches to infection/sepsis detection

Sepsis is a major healthcare problem from the perspective of mortality and economics. Advances in diagnostic detection of infection and sepsis have been slow, but recent advances in both soluble biomarker detection and quantitative cellular measurements promise the availability of improved diagnostic techniques. Though the promise of cytokine measurements reaching clinical practice have not matured, procalcitonin levels are currently available in many countries and appear to offer enhanced diagnostic distinction between bacterial and viral etiologies. Cellular diagnostics is poised to enter clinical laboratory practice in the form of neutrophil CD64 measurements, which offer superior sensitivity and specificity to conventional laboratory assessment of sepsis. Neutrophil CD64 expression is negligible in the healthy state. However, it increases as part of the systemic response to severe infection or sepsis. The combination of cellular proteomics, as in the case of neutrophil CD64 quantification, and selected soluble biomarkers of the inflammatory response, such as procalcitonin or triggering receptor expressed on myeloid cells (TREM)-1, is predicted to remove the current subjectivity and uncertainty in the diagnosis and therapeutic monitoring of infection and sepsis.

Immunologic markers in the neonatal period: diagnostic value and accuracy in infection

Diagnosis of early-onset neonatal infection has led to the development of several screening tests including C-reactive protein, a very commonly used marker, and cytokines (mainly interleukin-6 and -8), alone or in combination with C-reactive protein, based on the premise that their increases in response to infection may precede that of C-reactive protein. In recent years the search for diagnostic tests has turned to procalcitonin, a propeptide of calcitonin, which appears to be a promising marker of infection in newborn infants. Additionally, specific leukocyte cell surface antigens (mainly CD11b and CD64), detected by flow cytometry, are evaluated as markers of neonatal infection, since their expression on the cell membrane increases in substantial quantities after leukocyte activation by bacteria or their cellular products. This review aims to examine the role of these newly available immunologic indices and to assess their validity as diagnostic markers of infection during the neonatal period.

Serum Amyloid A Protein Is a Useful Inflammatory Marker during Late-Onset Sepsis in Preterm Infants

BACKGROUND

Few studies demonstrated that serum amyloid A (SAA), a non-specific acute-phase reactant, could be used as a reliable early marker for the diagnosis of late-onset sepsis (LOS).

OBJECTIVES

To evaluate the diagnostic value and the dynamics of SAA levels during the course of LOS and to compare it to those of other inflammatory markers.

METHODS

Levels of SAA, C-reactive protein (CRP) and IL-6 together with clinical variables, biochemical parameters and cultures retrieved from all preterm infants suspected of LOS were checked at the first suspicion of sepsis and after 8, 24, 48 and 72 h. Results were compared to healthy, matched infants.

RESULTS

One hundred and sixteen infants were included in the study, 38 in the sepsis and 78 in the non-sepsis group. High levels of SAA were observed at sepsis onset, with a gradual decline thereafter, while CRP levels increased only at 24 h after sepsis onset. In the sepsis group, levels of SAA returned faster to baseline than CRP levels. Receiver-operating characteristic analysis values revealed that SAA at 10 mug/ml had the highest sensitivity at 0, 8 and 24 h after sepsis onset (95, 100 and 97%, respectively) and a negative predictive value (97, 100 and 98%, respectively).

CONCLUSIONS

SAA is an accurate acute-phase protein during LOS in preterm infants. Quick and reliable SAA kits can make this marker a useful tool in LOS in preterm infants.

Clinical microbiology of bacterial and fungal sepsis in very-low-birth-weight infants

Twenty percent of very-low-birth-weight (<1500 g) preterm infants experience a serious systemic infection, and despite advances in neonatal intensive care and antimicrobials, mortality is as much as threefold higher for these infants who develop sepsis than their counterparts without sepsis during their hospitalization. Outcomes may be improved by preventative strategies, earlier and accurate diagnosis, and adjunct therapies to combat infection and protect the vulnerable preterm infant during an infection. Earlier diagnosis on the basis of factors such as abnormal heart rate characteristics may offer the ability to initiate treatment prior to the onset of clinical symptoms. Molecular and adjunctive diagnostics may also aid in diagnosing invasive infection when clinical symptoms indicate infection but no organisms are isolated in culture. Due to the high morbidity and mortality, preventative and adjunctive therapies are needed. Prophylaxis has been effective in preventing early-onset group B streptococcal sepsis and late-onset Candida sepsis. Future research in prophylaxis using active and passive immunization strategies offers prevention without the risk of resistance to antimicrobials. Identification of the differences in neonatal intensive care units with low and high infection rates and implementation of infection control measures remain paramount in each neonatal intensive care unit caring for preterm infants.

Implementation of evidence-based potentially better practices to decrease nosocomial infections

OBJECTIVE

Six neonatal intensive care units (NICUs) that are members of the Vermont Oxford National Evidence-Based Quality Improvement Collaborative for Neonatology collaborated to reduce infection rates. There were 7 centers in the original focus group, but 1 center left the collaborative after 1 year. Nosocomial infection is a significant area for improvement in most NICUs.

METHODS

Six NICUs participating in the Vermont Oxford Network made clinical changes to address 3 areas of consensus: handwashing, line management, and accuracy of diagnosis. The summary statements were widely communicated. Review of the literature, internal assessments, and benchmarking visits all contributed to ideas for change.

RESULTS

The principle outcome was the incidence of coagulase-negative staphylococcus bacteremia. There was an observed reduction from 24.6% in 1997 to 16.4% in 2000.

CONCLUSIONS

The collaborative process for clinical quality improvement can result in effective practice changes.

The role of C-reactive protein in the evaluation and management of infants with suspected sepsis

C-reactive protein (CRP) is a nonspecific, acute-phase protein that rises in response to infectious and noninfectious inflammatory processes. Good evidence exists to support the use of CRP measurements in conjunction with other established diagnostic tests (such as a white blood cell (WBC) count with differential and blood culture) to establish or exclude the diagnosis of sepsis in full-term or near-term infants. This article reviews the immunologic function of CRP and the history of CRP testing. The 3 methods for measuring CRP and the sensitivity and specificity of this diagnostic test are analyzed. Guidelines for the use of CRP in the evaluation and management of infants with suspected sepsis are presented. Quantitative serial CRP levels, obtained 24 hours after the onset of signs and symptoms of infection, with serial measurements 12 to 24 hours apart, offer the most sensitive and reliable information. At least 2 CRP levels, obtained 24 hours apart, with levels < or = 10 mg/L, are needed to identify infants unlikely to be infected. The use of CRP to exclude infection may allow clinicians to discontinue antibiotics at 48 hours in select infants, limiting extended unnecessary antibiotic exposure.