Accuracy of C-Reactive Protein Test for Neonatal Septicemia: A Diagnostic Meta-Analysis

An Observational Study on C-Reactive Protein to Platelet Ratio in Neonatal Sepsis

BACKGROUND

Neonatal sepsis is a serious medical condition affecting many individuals in the developing world. C-reactive protein (CRP) level in serum and platelet counts have been reported to have role in diagnosis of neonatal sepsis.

OBJECTIVE

To evaluate the CRP to Platelet ratio (CPR) in relation to time and blood culture reports in neonatal sepsis patients from a tertiary care centre in the Marathwada region of Maharashtra.

METHODS

The present observational study was conducted at the level III Neonatal Intensive Care Unit of a tertiary care centre in Aurangabad city of Marathwada region in Maharashtra from September 2022 to July 2023. The study included 120 neonates (delivered after completion of 28-42 weeks of gestation) with clinical/culture-positive sepsis. The newborns of seropositive mothers, neonates delivered in other hospitals, babies with congenital dysmorphic features, and babies requiring surgical procedures were excluded from the study. Blood samples for complete blood count (CBC) and CRP were collected on days 1, 3 and 5. Blood cultures were sent on day 1 of illness. Repeated measures ANOVA was used to compare the parameters of CPR, CRP, and platelet count in blood culture-positive and blood culture-negative neonatal sepsis patients on days 1, 3 and 5.

RESULTS

Blood culture was positive in 37 (30.8%) cases. A repeated measures ANOVA showed a significant overall difference in the CPR across days 1, 3, and 5 (p = 0.006). The CPR was significantly higher in culture-positive neonates compared to culture-negative neonates (p = 0.042).

CONCLUSION

Higher CPR in blood culture-positive neonates compared to blood culture-negative neonates supports the role of CPR in the diagnosis and management of neonatal sepsis.

MiRNAs as biomarkers for diagnosis of neonatal sepsis: a systematic review and meta-analysis

BACKGROUND

The relationship between circulating miRNAs and neonatal sepsis and the mechanism of action are still unclear at this time. Therefore, the potential diagnostic role of miRNAs in neonatal sepsis (NS) was studied through meta-analysis.

METHOD

Web of Science, Cochrane Library, PubMed, and Embase are retrieved, supplemented by manual search, and the search was conducted to find related studies without time limit until May 2022.The quality of the literature was assessed via QUADAS criteria and meta-analyzed via Stata 11.0 software, including the assessment of specificity, sensitivity, likelihood ratio and diagnostic odds ratio. Then, sensitivity analysis and heterogeneity testing were conducted, and finally, the summary receiver operating characteristics (SROC) curve was drawn.

RESULT

This study included 14 articles, including 20 miRNAs and 1597 newborns(control group: 727 and case group: 870). Among them, one article was of low quality, three articles were of high quality, and the rest were of medium quality. According to the results of random effects model analysis, the pooled specificity and sensitivity of miRNA for the diagnosis of NS were 0.83 (95%CI: 0.79-0.87) and 0.76 (95%CI: 0.72-0.80), respectively. And negative likelihood ratio, positive likelihood ratio, and diagnostic odds ratio were 0.29 (95%CI: 0.24-0.34), 4.51 (95%CI: 3.52-5.78), and 15.81 (95%CI: 10.71-23.35), respectively. The area under the SROC curve was 0.86, and there was no evidence publication bias detected in the funnel plot.

CONCLUSION

Circulating miRNAs may be very useful in the development of early diagnostic strategies for neonatal sepsis.

C-Reactive Protein: Pathophysiology, Diagnosis, False Test Results and a Novel Diagnostic Algorithm for Clinicians

The current literature provides a body of evidence on C-Reactive Protein (CRP) and its potential role in inflammation. However, most pieces of evidence are sparse and controversial. This critical state-of-the-art monography provides all the crucial data on the potential biochemical properties of the protein, along with further evidence on its potential pathobiology, both for its pentameric and monomeric forms, including information for its ligands as well as the possible function of autoantibodies against the protein. Furthermore, the current evidence on its potential utility as a biomarker of various diseases is presented, of all cardiovascular, respiratory, hepatobiliary, gastrointestinal, pancreatic, renal, gynecological, andrological, dental, oral, otorhinolaryngological, ophthalmological, dermatological, musculoskeletal, neurological, mental, splenic, thyroid conditions, as well as infections, autoimmune-supposed conditions and neoplasms, including other possible factors that have been linked with elevated concentrations of that protein. Moreover, data on molecular diagnostics on CRP are discussed, and possible etiologies of false test results are highlighted. Additionally, this review evaluates all current pieces of evidence on CRP and systemic inflammation, and highlights future goals. Finally, a novel diagnostic algorithm to carefully assess the CRP level for a precise diagnosis of a medical condition is illustrated.

Identification of new biomarkers and immune infiltration characteristics of sepsis in very low birth weight infants

Sepsis is a life-threatening condition, especially in very low birth weight (VLBW) infants, and its pathogenesis remains unclear. Effective biomarkers need to be found to diagnose and treat the disease at an early stage. The Gene Expression Omnibus (GEO) database was screened and analyzed for differentially expressed genes (DEGs) in VLBW infants with sepsis. DEGs were then analyzed for functional enrichment. A weighted gene co-expression network analysis (WCGNA) was performed to identify the key modules and genes. The optimal feature genes (OFGs) were created using three machine learning algorithms. The single-sample Gene Set Enrichment Analysis (ssGSEA) scored the degree of immune cell enrichment between septic and control patients, and the correlation between OFGs and immune cells was evaluated. A total of 101 DEGs were identified between the sepsis and control samples. DEGs were mainly associated with immune responses and inflammatory signaling pathways in the enrichment analysis. In the WGCNA analysis, the MEturquoise module was significantly correlated with sepsis in VLBW infants (cor = 0.57, P < 0.001). By intersecting OFGs derived from three machine learning algorithms, two biomarkers were identified: glycogenin 1 (GYG1) and resistin (RETN). The area under the curves of GYG1 and RETN was greater than 0.97 in the testing set. The ssGSEA indicated immune cells infiltration in septic VLBW infants, and GYG1 and RETN revealed close correlations with immune cells. New biomarkers offer promising insights into the diagnosis and treatment of sepsis in VLBW infants.

The evolving value of older biomarkers in the clinical diagnosis of pediatric sepsis

Sepsis remains the leading cause of childhood mortality worldwide. The evolving definition of pediatric sepsis is extrapolated from adult studies. Although lacking formal validation in the pediatric population, this working definition has historically proven its clinical utility. Prompt identification of pediatric sepsis is challenging as clinical picture is often variable. Timely intervention is crucial for optimal outcome, thus biomarkers are utilized to aid in immediate, yet judicious, diagnosis of sepsis. Over time, their use in sepsis has expanded with discovery of newer biomarkers that include genomic bio-signatures. Despite recent scientific advances, there is no biomarker that can accurately diagnose sepsis. Furthermore, older biomarkers are readily available in most institutions while newer biomarkers are not. Hence, the latter's clinical value in pediatric sepsis remains theoretical. Albeit promising, scarce data on newer biomarkers have been extracted from research settings making their clinical value unclear. As interest in newer biomarkers continue to proliferate despite their ambiguous clinical use, the literature on older biomarkers in clinical settings continue to diminish. Thus, revisiting the evolving value of these earliest biomarkers in optimizing pediatric sepsis diagnosis is warranted. This review focuses on the four most readily available biomarkers to bedside clinicians in diagnosing pediatric sepsis. IMPACT: The definition of pediatric sepsis remains an extrapolation from adult studies. Older biomarkers that include C-reactive protein, procalcitonin, ferritin, and lactate are the most readily available biomarkers in most pediatric institutions to aid in the diagnosis of pediatric sepsis. Older biomarkers, although in varying levels of reliability, remain to be useful clinical adjuncts in the diagnosis of pediatric sepsis if used in the appropriate clinical context. C-reactive protein and procalcitonin are more sensitive and specific among these older biomarkers in diagnosing pediatric sepsis although evidence varies in different age groups and clinical scenarios.

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.

The Role of C-reactive Protein Estimation in Determining the Duration of Antibiotic Therapy in Neonatal Sepsis

INTRODUCTION

Septicemia is globally considered the most important cause of neonatal morbidity and fatality. Serum C-Reactive Protein (CRP) is an acute phase reactant, which is brought out in response to the inflammatory reaction. It is prophesied to drop down speedily after the coherent weeding out of microbial incitation due to the short half-life of CRP. CRP levels reflect the individual's association between microbial infection and defensive mechanisms.  Methods: This hospital-based cross-sectional study included 150 admitted patients with suspected sepsis in the Department of Pediatrics, Rajendra Institute Medical Sciences (RIMS), Ranchi, India, over a study period of one year (2020 to 2021). CRP was estimated on the day of admission and repeated after 72 hours, on the fifth day, and on the seventh day for serial values of CRP, and the findings were compared by making three groups. Further, the research participants were designated to three different groups according to the CRP estimation levels.

RESULTS

Out of the 150 assumed neonatal septicemia patients, antibiotics were paused in 42 neonates (28%) within 72 hours. In group 2, 8% of neonates' antibiotics were stopped in five days, and a total of 102 neonates (68%) could be discharged on the seventh day of antibiotic therapy as their CRPs became negative on the third day and seventh day consecutively, along with negative blood culture reports. In group 3, antibiotics of 48 neonates (32%) were continued beyond seven days.

CONCLUSION

CRP has a skyscraping specificity and negative predictive values (NPV); thus, by estimating serial CRPs, the antibiotic therapy duration can be determined, which further helps determine the period of hospitalization.

Prognostic Role of Procalcitonin and C-reactive Protein in Surgical Neonates: A Single-Institution Experience

Introduction

Neonatal sepsis is a dynamic process where the rigorous evaluation of clinical signs along with appropriately selected biomarkers guides the diagnosis of sepsis. Procalcitonin (PCT) and C-reactive protein (CRP) are the two most commonly used diagnostic biomarkers used in sepsis. Sepsis remains the most important cause of mortality and morbidity in surgical neonates. A cross-sectional study was conducted to assess the prognostic predictability of PCT and CRP in neonatal surgical sepsis.

Methods

All the neonates admitted to the neonatal surgical intensive care unit between January 2019 and December 2020 with features of sepsis were included in the study. Blood cultures, CRP, and PCT on Day one (PCT1) and Day three (PCT3) of suspicion of sepsis were evaluated. The receiver operating characteristics curve was studied to estimate the probability of two markers to predict the mortality in neonatal sepsis.

Results

Of 102 surgical neonates, 63 neonates had early-onset sepsis while 23 (22.5%) neonates died and 30 neonates reported positive blood culture. There was a decline in the overall PCT trend from PCT1 and PCT3, while a significant PCT rise was noted for the non-survival group (p= 0.003). At cut-off of 5 mg/dl for CRP and 2.5 ng/dl for PCT1 and PCT3, the sensitivity (36.0%, 25.8%, 100%), specificity (84.1%, 83.3%, 97.5%), positive predictive value (52.2%, 73.9%, 91.3%), and negative predictive values (73.4%, 38.0%, 100%) were observed.

Conclusion

PCT on Day three of suspected sepsis has higher sensitivity, specificity, and accuracy for prognostication of surgical neonatal sepsis at the cut-off value of 2.5 ng/ml. The rising trend of PCT levels is indicative of a poor prognosis.

Comparing the Diagnostic Accuracy of Procalcitonin and C-Reactive Protein in Neonatal Sepsis: A Systematic Review

Neonatal sepsis remains a significant diagnostic challenge in newborn care. It has the potential to be disastrous, but precise diagnosis is difficult. No biomarker has yet demonstrated sufficient diagnostic accuracy to rule out sepsis when clinical suspicion exists. As a result, neonates with suspected sepsis are treated with empiric antibiotics. These unnecessary antibiotics promote bacterial antibiotic resistance, raise economic costs, and alter the composition of the gut microbiota. This study aimed to determine the diagnostic accuracy of procalcitonin in the prompt diagnosis of neonatal sepsis. Articles were systematically screened in PubMed/MEDLINE, PubMed Central (PMC), and ScienceDirect, using keywords and Medical Subject Heading (MeSH) terms to identify the relevant articles. Additionally, one article from the Indian Journal of Applied Research was also used. Inclusion/exclusion criteria were applied post article screening via title and abstracts. Quality appraisal check was done using the Scale for the Assessment of Narrative Review Articles (SANRA) checklist, A Measurement Tool to Assess Systematic Reviews (AMSTAR) checklist, and Newcastle-Ottawa checklist. Six related articles were strictly reviewed. Procalcitonin is a useful biomarker in the early diagnosis of neonatal sepsis. Because procalcitonin has a better correlation with proven sepsis and is an early biomarker in diagnosing neonatal sepsis, it should be included in the overall sepsis evaluation. Future clinical trials on optimal cut-off levels of procalcitonin with shifting neonatal ages and its use in the post-op setting are needed.

Clinical Value of C-Reactive Protein/Platelet Ratio in Neonatal Sepsis: A Cross-Sectional Study

Purpose

C-reactive protein (CRP) level and platelet (PLT) count have been demonstrated to be independent risk factor for neonatal sepsis. However, no data is currently available in regarding the association between CRP-to-PLT ratio (CPR) and neonatal sepsis.

Methods

A total of 1048 neonates with suspected sepsis were enrolled in this study. Complete clinical and laboratory data were collected. CPR was calculated as CRP (mg/L)/PLT (10⁷ cells/L). Multivariate logistic regression analysis was performed to identify the potential independent risk factors of neonatal sepsis. Receiver operating characteristic (ROC) curve analysis was used to evaluate the prediction accuracy of CPR in predicting neonatal sepsis.

Results

Neonates with sepsis had a higher CPR. CPR also showed a gradual increase in the infection, mild sepsis and severe sepsis groups. Multivariate analysis revealed that CPR was a significant independent predictor of the presence of neonatal sepsis (odds ratio [OR], 1.015; 95% confidence interval [CI], 1.008-1.022, P < 0.001) and severe sepsis (OR, 1.002; 95% CI, 1.000-1.003, P = 0.007). ROC curve revealed showed that CPR had a well-discriminatory power in predicting sepsis (area under curve [AUC], 0.68; 95% CI, 0.65-0.72, P < 0.001) and severe sepsis (AUC, 0.68; 95% CI, 0.65-0.72, P < 0.001).

Conclusion

The present study demonstrated that a higher CPR is an independent predictor of the presence and severity of neonatal sepsis.

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.

IL-6 Predicts Poor Early Post-Natal Growth in Very Low-Birth-Weight Infants in a Low-Middle Income Setting

BACKGROUND

Extra-uterine growth restriction (EUGR) is common in preterms and may be associated with elevated pro-inflammatory cytokines.

OBJECTIVE

Describe postnatal growth in a cohort of very low-birth-weight (VLBW) infants and determine the association of interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF-α) in umbilical cord blood with growth at 40 weeks and 12 months postmenstrual age (PMA).

METHODS

Single-centre, prospective cohort study conducted from 1 June 2017 to 31 January 2019 with follow-up to 31 March 2020. Infants <1500 g at birth were enrolled, cord blood collected for IL-6 and TNF-α assays and postnatal care, including anthropometry, provided to 12 months PMA. Informed consent and ethics approval were obtained.

RESULTS

In total, 279 patients were enrolled; 84 (30.1%) died before 12 months and 91 (32.6%) lost to follow-up. Anthropometry was available for 151 infants at 40 weeks and 105 at 12 months. Z-Scores at 40 weeks for males and females combined were -2.5, -2.1 and -1.2 for weight, length and head circumference. EUGR occurred in 103/113 (91.2%), 98/107 (91.6%) and 70/109 (64.2%) participants for weight, length and head circumference. Elevated IL-6 was associated with restricted weight (56.0 vs. 14.5 pg/ml, p = 0.02) and length (60.4 vs. 7.3 pg/ml, p = 0.01) at 40 weeks. There was no difference in IL-6 at 12 months and no difference in TNF-α at 40 weeks or 12 months.

CONCLUSION

The study reports significant EUGR. Elevated IL-6 was associated with growth restriction at 40 weeks but not 12 months PMA.