Association between C-reactive protein levels and outcome in acute lung injury in children

Routine laboratory test to assess the need of respiratory support in acute bronchiolitis

BACKGROUND AND OBJECTIVES

Accurate and readily available biomarkers to predict the clinical course of bronchiolitis would enable enhanced decision-making in this setting. We explored the relationship of several biochemical parameters available at the pediatric emergency care setting with the need of advanced respiratory support (ARS): continuous positive airway pressure (CPAP), biphasic positive airway pressure (BiPAP), or invasive mechanical ventilation (MV) in bronchiolitis.

METHODS

Single-center, prospective, observational, including infants aged less than 12 months diagnosed with acute bronchiolitis at the Pediatric Emergency Department. Determination of plasmatic values of several laboratory tests was performed at the time of hospital admission. Multivariate logistic analysis identified independent predictors for need of ARS.

RESULTS

From October 1, 2018 to May 1, 2020, we recruited 149 infants (58% males; median age of 1 [0.5-2.5] month). Thirty-seven (25%) cases required ARS. After adjusting by age, bacterial superinfection, and comorbidities in the multivariate analysis, only higher levels of glycemia (p = 0.001), C-reactive protein (CRP) (p = 0.028), CRP/albumin ratio (p = 0.032), and NT-proBNP (p = 0.001) remained independently associated with ARS. These biomarkers reached moderate prediction accuracy with area under the curve of receiver operator curve curves ranging from 0.701 to 0.830 (p = 0.001). All they presented relatively high specificity (0.75-0.84) and negative predictive values (0.77-0.89) with low sensitivity and positive predictive values. They also correlated significantly with length of stay hospitalization (p = 0.001).

CONCLUSION

Increased plasmatic levels of CRP, CRP/albumin ratio, glycemia, and NT-proBNP at hospital admission are associated with the need for ARS in infants with acute bronchiolitis.

Risk Factors of Mechanical Ventilation in Premature Infants During Hospitalization

Background

The purpose of this study was to identify the risk factors for premature neonates requiring mechanical ventilation.

Methods

Premature neonates admitted to Chengdu Women’s and Children’s Central Hospital between July 2014 and December 2020 were retrospectively included in this study. Clinical and demographic factors were collated. Univariate and multivariate logistic regression analyses were conducted to identify the risk factors for premature infants requiring mechanical ventilation.

Results

A total of 1262 premature neonates participated in the study. Among them, 423 (33.53%) neonates required mechanical ventilation, whereas 839 (66.48%) neonates did not require mechanical ventilation. Multivariate logistic regression analysis determined that a lower Apgar score at 5 min (OR = 0.595, 95% CI: 0.472–0.74; P < 0.001), lower gestational age (very preterm) (OR = 11.745, 95% CI: 4.362, 31.619, P < 0.001), lower systolic blood pressure (OR = 0.864, 95% CI: 0.812–0.917, P = 0.001), lower diastolic blood pressure (OR = 0.894, 95% CI: 0.831–0.96, P = 0.002), higher respiratory rate (OR = 1.292, 95% CI: 1.238–1.355, P < 0.001), increased C-reactive protein levels (OR=1.044, 95% CI: 1.003–1.086, P = 0.036), and presence of patent ductus arteriosus (OR = 2.174, 95% CI: 1.185–3.972, P = 0.012) were independently associated with an increased possibility of adopting mechanical ventilation in premature infants. ROC analysis demonstrated that the predicted power for premature neonates requiring mechanical ventilation was 0.855 (95% CI: 0.808–0.902, P < 0.001).

Conclusion

In conclusion, we determined that a lower Apgar score at 5 min, lower gestational age, lower systolic blood pressure, lower diastolic blood pressure, higher respiratory rate, increased C-reactive protein levels and presence of patent ductus arteriosus were independently associated with an increased possibility of adopting mechanical ventilation in premature infants.

Usefulness of RBC distribution width and C-reactive protein to predict mortality in pediatric non-cardiac critical illness

INTRODUCTION

We aimed to assess the performance of red blood cell distribution width (RDW), C-reactive protein (CRP) or the combination of both to predict clinical outcomes in pediatric non-cardiovascular critical illness.

MATERIALS AND METHODS

We analyzed 404 pediatric non-cardiovascular critically ill patients admitted to pediatric intensive care unit (PICU). Potential predictors were identified using multivariable logistic regression. We also calculated the power of RDW and CRP additive to pediatric critical illness score (PCIS) to predict mortality with calculation of C-index value, integrated discrimination improvement (IDI) and net reclassification improvement (NRI) indices.

RESULTS

RDW and CRP independently predicted PICU mortality. The C-index value of PCIS with respect to prediction of PICU mortality was greater than that of RDW and CRP. The combination of RDW or CRP or both with PCIS did significantly increase C-index value for predicting mortality (all p < 0.01). Addition of RDW or CRP or their combination to PCIS provided IDI of 7%, 1.1% and 9.4% (p = 0.009, 0.01 and 0.003) and NRI of 15.9%, 13.1% and 19.6% (p = 0.002, 0.043 and 0.002), respectively.

CONCLUSIONS

In pediatric non-cardiovascular critically ill patients, RDW and CRP could serve as independent predictors of PICU mortality and addition of RDW or CRP or both to PCIS significantly improves the ability to predict PICU mortality.

Biomarkers in Pediatric ARDS: Future Directions

Acute respiratory distress syndrome (ARDS) is common among mechanically ventilated children and accompanies up to 30% of all pediatric intensive care unit deaths. Though ARDS diagnosis is based on clinical criteria, biological markers of acute lung damage have been extensively studied in adults and children. Biomarkers of inflammation, alveolar epithelial and capillary endothelial disruption, disordered coagulation, and associated derangements measured in the circulation and other body fluids, such as bronchoalveolar lavage, have improved our understanding of pathobiology of ARDS. The biochemical signature of ARDS has been increasingly well described in adult populations, and this has led to the identification of molecular phenotypes to augment clinical classifications. However, there is a paucity of data from pediatric ARDS (pARDS) patients. Biomarkers and molecular phenotypes have the potential to identify patients at high risk of poor outcomes, and perhaps inform the development of targeted therapies for specific groups of patients. Additionally, because of the lower incidence of and mortality from ARDS in pediatric patients relative to adults and lack of robust clinical predictors of outcome, there is an ongoing interest in biological markers as surrogate outcome measures. The recent definition of pARDS provides additional impetus for the measurement of established and novel biomarkers in future pediatric studies in order to further characterize this disease process. This chapter will review the currently available literature and discuss potential future directions for investigation into biomarkers in ARDS among children.

Circulating nucleosomes are associated with mortality in pediatric acute respiratory distress syndrome

Mechanisms underlying pediatric acute respiratory distress syndrome (PARDS) are poorly understood. The recent implication of circulating nucleosomes as pathogenic in sepsis and trauma-associated ARDS in adults led us to investigate the significance of nucleosomes in PARDS. We conducted a prospective, observational study on children with PARDS at the Children's Hospital of Philadelphia between July 2014 and September 2015. Plasma was collected within 48 h of PARDS onset and nucleosomes quantified by enzyme-linked immunosorbent assay. Samples from 76 children with PARDS (11 deaths, 14%) were collected early [median 15 (IQR 7, 21) h] after PARDS onset. Nucleosome levels were higher in nonsurvivors [0.59 AU (IQR 0.46, 0.84)] relative to survivors [0.21 AU (IQR 0.08, 0.33), rank sum P < 0.001]. Nucleosome levels were not associated with either Berlin (P = 0.845) or PALICC (P = 0.886) oxygenation categories, nor with etiology of PARDS (P = 0.527). Nucleosomes were correlated with increasing numbers of nonpulmonary organ failures (P = 0.009 for trend), and were higher in patients whose PaO2 /FiO2 worsened (P = 0.012) over the first 72 h of PARDS. In regression analysis, nucleosome levels were independently associated with mortality after adjusting for either age, severity of illness score, number of nonpulmonary organ failures, vasopressor score, or PaO2 /FiO2 (all P < 0.05). In conclusion, plasma nucleosome levels in early PARDS were associated with increased mortality, correlated with number of nonpulmonary organ failures, and preceded worsening oxygenation. The potential utility of this biomarker for prognostication, risk stratification, and mechanistic insight should be investigated further.

C-reactive protein and lung diseases

C-reactive protein (CRP), a member of the pentraxin family of plasma proteins, is one of the most distinctive acute phase reactants. In response to inflammation, cell damage or tissue injury, plasma level of CRP rapidly and dramatically increases up to 1000-fold, a phenomenon that has been used for years to monitor infections and many destructive/inflammatory conditions. The magnitude of CRP increase usually correlates with the severity of injury or inflammation and reflects an important physiological role of this interesting but still under-investigated protein. It is now generally accepted that CRP is involved in host defense and inflammation. However, the exact function of this protein in health and disease remains unclear. Many studies have demonstrated that in different pathophysiological conditions CRP might be involved in the regulation of lung function and may participate in the pathogenesis of various pulmonary disorders. The fluctuation of CRP concentrations in both alveolar fluid and serum associated with different pulmonary diseases suggests its important role in lung biology. Discussion of the still controversial functions of CRP in lung physiology and diseases is the main focus of this review.