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

Clinical prediction models to diagnose neonatal sepsis in low-income and middle-income countries: a scoping review

INTRODUCTION

Neonatal sepsis causes significant morbidity and mortality worldwide but is difficult to diagnose clinically. Clinical prediction models (CPMs) could improve diagnostic accuracy, facilitating earlier treatment for cases and avoiding antibiotic overuse. Neonates in low-income and middle-income countries (LMICs) are disproportionately affected by sepsis, yet no review has comprehensively synthesised evidence for CPMs validated in this setting.

METHODS

We performed a scoping review of CPMs to diagnose neonatal sepsis using Ovid MEDLINE, Ovid Embase, Scopus, Web of Science, Global Index Medicus and the Cochrane Library. The most recent searches were performed on 16 June 2024. We included studies published in English or Spanish that validated a new or existing CPM for neonatal sepsis in any healthcare setting in an LMIC. Studies were excluded if they validated a prognostic model or where data for neonates could not be separated from a larger paediatric population. Studies were selected by two independent reviewers and summarised by narrative synthesis.

RESULTS

From 4598 unique records, we included 82 studies validating 44 distinct models in 24 252 neonates. Most studies were set in neonatal intensive or special care units (n=64, 78%) in middle-income countries (n=81, 99%) and included neonates already suspected of sepsis (n=58, 71%). Only four studies (5%) were set in the WHO African region, and only one study included data from a low-income country. Two-thirds of CPMs (n=30) required laboratory parameters, and three-quarters (n=34) were only validated in one study.

CONCLUSION

Our review highlights several literature gaps, particularly a paucity of studies validating models in the lowest-income countries where neonatal sepsis is most prevalent, and models for the undifferentiated neonatal population that do not rely on laboratory tests. Furthermore, heterogeneity in study populations, definitions of sepsis and reporting of models inhibits meaningful comparison between studies and may hinder progress towards useful diagnostic tools.

Carboxyhemoglobin Levels in Preterm Neonatal Late-Onset Sepsis: to Predict or not to Predict

Background

In this study, we aimed to evaluate carboxyhemoglobin (COHb) levels in diagnosing late-onset sepsis (LOS) in preterm neonates.

Methods

The records of culture-positive LOS in preterm neonates hospitalized in NICU from January 2017 to July 2022 were reviewed. COHb levels, C-reactive protein, procalcitonin, and neutrophil to lymphocyte ratio of septic preterm infants were compared to controls. In addition, serial COHb levels measured within six hours before or 24h after blood culture sampling, three to seven days prior, and three to five days after starting antimicrobial therapy were retrieved from patient records.

Results

The study included 77 blood-culture-positive preterm infants and 77 non-septic controls. During the LOS episode, the COHb values were found to be significantly increased (median: 1.8, IQR: 1.4-2.5) when compared to the control group (median: 1.2, IQR: 0.8-1.6) (p < 0.001). ROC analysis yielded an AUC of 0.714 for COHb (95% CI: 0.631-0.796, p<0.001). At an optimal cut-off of >1.5%, the test's sensitivity was 64.94%, the specificity was 72.73%, the positive predictive value was 70.42%, and the negative predictive value was 67.47%. LOS led to a dramatic rise followed by a decrease after the initiation of the antimicrobial therapy [1.8 (1.4-2.5)] vs. [1.45 (0.2-4)] p<0.001.

Conclusion

COHb levels increased at the beginning of LOS, decreasing in response to antibiotics. When used in conjunction with other sepsis biomarkers, the variation of COHb can be important in evaluating late-onset sepsis episodes in preterm infants.