Procalcitonin, C-reactive protein, neutrophil gelatinase-associated lipocalin, resistin and the APTT waveform for the early diagnosis of serious bacterial infection and prediction of outcome in critically ill children

Procalcitonin-guided duration of antibiotic treatment in children hospitalised with confirmed or suspected bacterial infection in the UK (BATCH): a pragmatic, multicentre, open-label, two-arm, individually randomised, controlled trial

BACKGROUND

Procalcitonin is a rapid response biomarker specific for bacterial infection, which is not routinely used in the UK National Health Service. We aimed to assess whether using a procalcitonin-guided algorithm would safely reduce the duration of antibiotic therapy compared with usual care, in which C-reactive protein is the commonly used biomarker.

METHODS

The BATCH trial was a pragmatic, multicentre, open-label, parallel, two-arm, individually randomised, controlled trial conducted in 15 hospitals in England and Wales. Children aged 72 h to 18 years who were admitted to hospital and were being treated with intravenous antibiotics for suspected or confirmed bacterial infection and who were expected to remain on intravenous antibiotics for more than 48 h were enrolled. Participants were randomly assigned (1:1) to receive either current clinical management alone (usual care group) or clinical management with the addition of a procalcitonin test guided algorithm (procalcitonin group). Participants were randomly assigned by minimisation, with site and age group (0-6 months, 6 months to 2 years, 2-5 years, and older than 5 years) as minimisation factors and a random element to reduce predictability. Participants were randomly assigned remotely using a secure 24 h web-based randomisation programme. The coprimary outcomes were duration of intravenous antibiotic use, assessed for superiority, and a composite safety measure, assessed for non-inferiority (non-inferiority margin 5%). The primary analysis sample for each coprimary endpoint included all randomly assigned participants with available outcome data. This trial is registered with the International Standard Randomised Controlled Trial Number registry, ISRCTN11369832.

FINDINGS

Between June 11, 2018, and Oct 12, 2022, 15 282 children were screened for eligibility, 1949 of whom were randomly assigned to receive procalcitonin-guided antibiotic therapy (n=977) or usual care (n=972). The median intravenous antibiotic duration was 96·0 h (IQR 59·5-155·5) in the procalcitonin group and 99·7 h (61·2-153·8) in the usual care group (hazard ratio 0·96 [95% CI 0·87-1·05]). 78 (9%) of 917 participants in the procalcitonin group and 85 (9%) of 904 participants in the usual care group had at least one event covered by the composite safety outcome measure (estimated adjusted risk difference -0·81% [95% CI upper bound 1·11]).

INTERPRETATION

In children with suspected or confirmed bacterial infection admitted to hospitals in England and Wales for intravenous antibiotic treatment of at least 48 h, the introduction of a procalcitonin-guided algorithm did not reduce duration of intravenous antibiotics treatment and is non-inferior to usual care for safety outcomes. Therefore, evidence does not support the use of procalcitonin-guided algorithms where robust effective paediatric antibiotic stewardship programmes are established.

FUNDING

National Institute for Health and Care Research.

Prediction of Acute Kidney Injury Development in Critically Ill Septic Patients Based on NGAL Determination

Acute kidney injury (AKI) is a consequence of several diseases that can severely damage kidney function. It is a frequent complication of hospitalization and very common in critically ill patients because of other serious illnesses, such as septic conditions. New diagnostic options, including renal biomarkers, may help in early diagnosis. Our study included 46 patients, 31 with AKI and 15 without AKI on admission. Blood samples were collected on the first, fourth, and seventh days of treatment, and in addition to basic biochemical parameters, neutrophil gelatinase-associated lipocalin (NGAL) levels in serum were also examined. Data from the first and seventh day were used for statistical analysis. On the first follow-up day, NGAL values were categorized according to an optimal cut-off value of 290 µg/l. We demonstrated that if NGAL levels were higher, the risk of renal injury increased approximately 16 times. Other results showed that NGAL levels were moderately correlated with serum creatinine (r = 0.613, p < 0.0001), procalcitonin (PCT) (r = 0.627, p < 0.0001), and AKI stage (r = 0.589, p < 0.0001). There was also a significant positive correlation with SOFA (Sequential Organ Failure Assessment) score (r = 0.395, p = 0.007). Early diagnosis and treatment are crucial in managing AKI and preventing further kidney damage. NGAL levels can increase within a few hours after injury, making it a useful tool for early AKI detection and diagnosis. Key words: Acute kidney injury, Biomarker, NGAL, Sepsis.

Development and validation of risk prediction model for bacterial infections in acute liver failure patients

Infections significantly increase mortality in acute liver failure (ALF) patients, and there are no risk prediction models for early diagnosis and treatment of infections in ALF patients. This study aims to develop a risk prediction model for bacterial infections in ALF patients to guide rational antibiotic therapy. The data of ALF patients admitted to the Second Hospital of Hebei Medical University in China from January 2017 to January 2022 were retrospectively analyzed for training and internal validation. Patients were selected according to the updated 2011 American Association for the Study of Liver Diseases position paper on ALF. Serological indicators and model scores were collected within 24 h of admission. New models were developed using the multivariate logistic regression analysis. An optimal model was selected by receiver operating characteristic (ROC) analysis, Hosmer-Lemeshow test, the calibration curve, the Brier score, the bootstrap resampling, and the decision curve analysis. A nomogram was plotted to visualize the results. A total of 125 ALF patients were evaluated and 79 were included in the training set. The neutrophil-to-lymphocyte ratio and sequential organ failure assessment (SOFA) were integrated into the new model as independent predictive factors. The new SOFA-based model outperformed other models with an area under the ROC curve of 0.799 [95% confidence interval (CI): 0.652-0.926], the superior calibration and predictive performance in internal validation. High-risk individuals with a nomogram score ≥26 are recommended for antibiotic therapy. The new SOFA-based model demonstrates high accuracy and clinical utility in guiding antibiotic therapy in ALF patients.

The effects of antibiotic therapy on neonatal sepsis-associated acute kidney injury

AIM

Neonatal sepsis remains one of the most dangerous conditions in the neonatal intensive care units. One of the organs affected by sepsis is the kidney, making acute kidney injury (AKI) a common complication of sepsis. Treatment of sepsis almost always involves antibiotic therapy, which by itself may cause some adverse effects, including nephrotoxicity. We analyzed the mutual effect of antibiotic therapy and sepsis on AKI in an experimental and clinical study in infants and neonatal rats.

MATERIALS AND METHODS

We evaluated the influence of therapy with different antibiotics on the appearance of AKI markers (blood urea nitrogen (BUN), neutrophil gelatinase-associated lipocalin (NGAL), clusterin, interleukin-18 (IL-18), kidney injury molecule-1 (KIM-1), monocyte chemoattractant protein 1 (MCP-1), calbindin, glutation-S-transferase subtype π (GST-π)) and liver injury markers in newborns with or without clinical signs of sepsis in the intensive care unit. In parallel, we analyzed the development of AKI in experimental lipopolysaccharide (LPS)-induced systemic inflammation in newborn rats accompanied by antibiotic therapy.

KEY FINDINGS

We showed that therapy with metronidazole or ampicillin in combination with sulbactam had a beneficial effect in children with suspected sepsis, resulting in a decrease in AKI markers levels. However, treatment of newborns with netilmicin, cefepime, linezolid, or imipenem in combination with cilastatin worsened kidney function in these patients.

SIGNIFICANCE

This prospective study indicates which antibiotics are preferable in neonatal sepsis and which should be used with caution in view of the risk of AKI development.

Role of C-reactive protein in disease progression, diagnosis and management

C-reactive protein (CRP) is a ring-shaped pentameric protein synthesized in the liver via CRP gene transcription. It is an inflammatory marker, whose serum levels can be measured using traditional and high-sensitivity tests. In healthy adults, the normal CRP serum concentrations vary between 0.8 mg/L and 3.0 mg/L. These can be grouped into low-, moderate-, and high-risk categories according to CRP levels of less than 1, 1-3, and greater than 3 mg/L, respectively. Elevated levels have been observed in infections, autoimmune diseases, neurodegenerative disorders, and malignancies. However, it is not specific to any disease. Serum CRP levels have also been shown to indicate the risk of cardiovascular disease, owing to their role as inflammatory markers in atherosclerosis, coronary artery disease, and peripheral arterial disease. Furthermore, its role in autoimmune diseases, such as Systemic Lupus Erythematosus and rheumatoid arthritis, and its involvement in the development of cancers, including breast, colorectal, ovarian, prostate, and lung cancers, have also been studied. The involvement of CRP in determining the course of infection and differentiating between bacterial and viral infections has also been investigated. This review summarizes the published literature on C-reactive protein and its role in disease management and progression.

Biomarker-guided duration of antibiotic treatment in children hospitalised with confirmed or suspected bacterial infection: statistical analysis plan for the BATCH trial and PRECISE sub-study

INTRODUCTION

The BATCH trial is a multi-centre randomised controlled trial to compare procalcitonin-guided management of severe bacterial infection in children with current management. PRECISE is a mechanistic sub-study embedded into the BATCH trial. This paper describes the statistical analysis plan for the BATCH trial and PRECISE sub-study.

METHODS

The BATCH trial will assess the effectiveness of an additional procalcitonin test in children (aged 72 h to 18 years) hospitalised with suspected or confirmed bacterial infection to guide antimicrobial prescribing decisions. Participants will be enrolled in the trial from randomisation until day 28 follow-up. The co-primary outcomes are duration of intravenous antibiotic use and a composite safety outcome. Target sample size is 1942 patients, based on detecting a 1-day reduction in intravenous antibiotic use (90% power, two-sided) and on a non-inferiority margin of 5% risk difference in the composite safety outcome (90% power, one-sided), while allowing for up to 10% loss to follow-up.

RESULTS

Baseline characteristics will be summarised overall, by trial arm, and by whether patients were recruited before or after the pause in recruitment due to the COVID-19 pandemic. In the primary analysis, duration of intravenous antibiotic use will be tested for superiority using Cox regression, and the composite safety outcome will be tested for non-inferiority using logistic regression. The intervention will be judged successful if it reduces the duration of intravenous antibiotic use without compromising safety. Secondary analyses will include sensitivity analyses, pre-specified subgroup analyses, and analysis of secondary outcomes. Two sub-studies, including PRECISE, involve additional pre-specified subgroup analyses. All analyses will be adjusted for the balancing factors used in the randomisation, namely centre and patient age.

CONCLUSION

We describe the statistical analysis plan for the BATCH trial and PRECISE sub-study, including definitions of clinical outcomes, reporting guidelines, statistical principles, and analysis methods. The trial uses a design with co-primary superiority and non-inferiority endpoints. The analysis plan has been written prior to the completion of follow-up.

TRIAL REGISTRATION

BATCH: ISRCTN11369832, registered 20 September 2017, doi.org/10.1186/ISRCTN11369832.

PRECISE

ISRCTN14945050, registered 17 December 2020, doi.org/10.1186/ISRCTN14945050.

One-Shot Full-Range Quantification of Multi-Biomarkers With Different Abundance by a Tandem Giant Magnetoresistance Assay

In this study, we reported a tandem giant magnetoresistance (GMR) assay that realized the one-shot quantification of multi-biomarkers of infection, C-reactive protein (CRP) with procalcitonin (PCT), and neutrophil gelatinase-associated lipocalin (NGAL), all of which could cover their clinically relevant concentration ranges under a different principle. In the presence of co-determined assay, we quantified these three biomarkers in undiluted human blood serum in a single test. The tandem principle, based on which quantification of CRP occurs, combines a sandwich assay and an indirect competitive assay, which allows for the discrimination of the concentration values resulting from the multivalued dose-response curve (‘Hook’ effect), which characterizes the one-step sandwich assay at high CRP concentrations. However, the entire diagnostically dynamic range, in the quantification of PCT and NGAL, was achieved by differential coating of two identical GMR sensors operated in tandem and by combining two standard curves. The sensor quantified low detection limits and a broader dynamic range for the detection of infection biomarkers. The noticeable features of the assay are its dynamic range and small sample volume requirement (50 μL), and the need for a short measurement time of 15 min. These figures of merit render it a prospective candidate for practical use in point-of-care analysis.

Biomarker-guided duration of Antibiotic Treatment in Children Hospitalised with confirmed or suspected bacterial infection (BATCH): protocol for a randomised controlled trial

INTRODUCTION

Procalcitonin (PCT) is a biomarker more specific for bacterial infection and responds quicker than other commonly used biomarkers such as C reactive protein, but is not routinely used in the National Health Service (NHS). Studies mainly in adults show that using PCT to guide clinicians may reduce antibiotic use, reduce hospital stay, with no associated adverse effects such as increased rates of hospital re-admission, incomplete treatment of infections, relapse or death. A review conducted for National Institute for Health and Care Excellence recommends further research on PCT testing to guide antibiotic use in children.

METHODS AND ANALYSIS

Biomarker-guided duration of Antibiotic Treatment in Children Hospitalised with confirmed or suspected bacterial infection is a multi-centre, prospective, two-arm, individually Randomised Controlled Trial (RCT) with a 28-day follow-up and internal pilot. The intervention is a PCT-guided algorithm used in conjunction with best practice. The control arm is best practice alone. We plan to recruit 1942 children, aged between 72 hours and up to 18 years old, who are admitted to the hospital and being treated with intravenous antibiotics for suspected or confirmed bacterial infection. Coprimary outcomes are duration of antibiotic use and a composite safety measure. Secondary outcomes include time to switch from broad to narrow spectrum antibiotics, time to discharge, adverse drug reactions, health utility and cost-effectiveness. We will also perform a qualitative process evaluation. Recruitment commenced in June 2018 and paused briefly between March and May 2020 due to the COVID-19 pandemic.

ETHICS AND DISSEMINATION

The trial protocol was approved by the HRA and NHS REC (North West Liverpool East REC reference 18/NW/0100). We will publish the results in international peer-reviewed journals and present at scientific meetings.

TRIAL REGISTRATION NUMBER

ISRCTN11369832.