Correlation between urinary and serum NT-proBNP in acute bronchiolitis: A pilot study

BACKGROUND AND AIMS

We aimed to analyze the correlation of urinary with serum N-terminal pro-brain natriuretic peptide (NT-proBNP) concentrations and its association with severity in acute bronchiolitis.

MATERIAL AND METHODS

A pilot observational study was conducted between October 1, 2021 and March 31, 2022 including acute bronchiolitis cases who attended our institution. Serum and urinary NT-proBNP concentrations were determined using the Alere i NT-proBNP assay in time-matched urine and blood samples. The Mann-Whitney U test, Spearman's correlations, and simple linear regression were utilized to analyze the association of urine NT-proBNP levels with serum NT-proBNP and with variables indicative of severe bronchiolitis.

RESULTS

Seventeen infants (median age 68 [IQR: 36-91] days) with 36 time-matched samples were included. The urine NT-proBNP was positively and strongly correlated with the serum NT-proBNP concentrations (Spearman's ρ = 0.81 & R2  coefficient = 0.751; p < 0.001), and increased with higher C-reactive protein, (p = 0.004), procalcitonin (p = 0.001), and pCO2 (p = 0.029) levels. The initial urinary NT-proBNP concentrations were higher in those infants that required ventilatory support compared with those without this outcome (1.85 [IQR: 1.16-2.44] vs. 0.63 [IQR: 0.45-0.84] pg/mg); p < 0.001); and resulted positively and strongly correlated with the duration of the ventilatory support (Spearman's ρ = 0.76; p < 0.001) and the length of stay hospitalization (Spearman's ρ = 0.84; p < 0.001).

CONCLUSION

The urinary NT-proBNP concentrations could be a reliable surrogate for serum NT-proBNP levels and resulted elevated in cases of acute bronchiolitis with complicated evolution, suggesting a potential as a noninvasive tool to assess severity in this setting.

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.

The Pivotal Role of Echocardiography in the Diagnosis of Stress-Induced Cardiomyopathy Presenting with a Typical Pattern in Critically Ill Children. An Illustrative Case Report

BACKGROUND

Takotsubo cardiomyopathy (TCM) has some distinctive features like greater proportion of reverse-TCM and disease of central nervous system as a prevalent triggering cause. We expose the case of a child with cardiogenic shock presenting an atypical echocardiographic TCM pattern on echocardiography, after an acute neurologic trigger. We also include a systematic review of the literature of previously described cases of atypical-TCM in children.

CASE REPORT

A previously healthy 9 year-old boy with status epilepticus who presented abrupt cardiogenic shock. The EKG showed signs of myocardial ischemia, cardiac biomarkers NT-proBNP (2756 pg/mL ) and Troponin I (1707 pg/mL ) were raised, and echocardiography exposed a dilated LV with severely reduced systolic function (LVEF 28%) along with hypokinetic mid-basal segments (circumferential ballooning) and preserved hypercontractile apical segments, with normal origin of both coronary arterial systems. A presumptive diagnosis of "reverse", "inverse" or atypical Takotsubo cardiomyopathy was build based on the echocardiographic findings, apart from the ACS-like EKG findings, the raised cardiac biomarkers and the neurological trigger of the hypercatecholaminergic state. Despite cardiovascular improvement with supportive treatment, the patient eventually expired on day 2 after PICU admission due to neurological complications. As shown in our systematic review, only 19 similar cases have been reported to date.

CONCLUSION

With the report of this unusual case, we aim to point out the fundamental role of bedside echocardiography as diagnostic test for critically ill children presenting with ACS-like in the context of neurosurgical emergencies, where bedside echocardiography itself can accurately establish a presumptive diagnosis of TCM.

Early elevated NT-proBNP but not troponin I is associated with severe bronchiolitis in infants

BACKGROUND

We aimed to explore and to compare the association between the NT-proBNP and high-sensitivity troponin I (hs-cTnI) at early stages of acute bronchiolitis with echocardiographic alterations, clinical severity and outcomes.

METHODS

A single centre, prospective observational study including previously healthy infants aged 1-12 months with bronchiolitis admitted to a tertiary hospital from April 2019 to March 2020. All patients underwent clinical, laboratory and echocardiographic evaluation at the same time point within 12 h of hospital admission. NT-proBNP > 1121 pg/ml and hs-cTnI > 26 ng/L were considered elevated. The primary outcome measure was the association of raised cardiac biomarkers with the need for PICU admission.

RESULTS

We enrolled 40 infants with median levels of NT-proBNP of 1176 (520-3030) pg/ml and hs-cTnI of 11.5 (5-21) ng/L at the time of hospital admission. Raised levels of NT-proBNP and hs-cTnI in 50% and 20% of cases, respectively. Of them, 15 (37%) required PICU admission during the hospitalization. Increased NT-proBNP was associated with PICU admission (adjusted OR 9.5 (CI95% 1.4-64); p = 0.020), prolonged hospitalization (β = 2.7; p = 0.012) and duration of oxygen administration (β = 2.7; p = 0.004) in the multivariate analysis. There were no differences in hs-cTnI levels regarding PICU admission (p = 0.866). Increased hs-cTnI levels were only associated with oxygen administration duration (Spearman rho = 0.38; p = 0.017), but this association disappeared in the multivariate analysis. Only NT-proBNP was associated with echocardiographic parameters of myocardial dysfunction (p < 0.001), and pulmonary hypertension (p < 0.001) CONCLUSION: Early elevated NT-proBNP but not hs-cTnI could be used as a biomarker for myocardial strain and disease severity in bronchiolitis.

Reproducibility and reference values of diaphragmatic shortening fraction for term and premature infants

BACKGROUND

New ultrasound measurements to diagnose diaphragmatic dysfunction, including diaphragmatic shortening fraction (DSF), have been studied in adults and children, but there are no data on reference values for neonates.

OBJECTIVE

To describe DSF reference values for term neonate (TN) and preterm neonate (PTN), and to calculate its reproducibility.

METHODS

We included asymptomatic TN and PTN during their first 24 hours of life. We measured DSF at the zone of apposition in both hemithoraces. Reproducibility of image acquisition, including inter- and intra-rater agreement of the measurements were calculated among an experienced and a novel operator (after completion of a 1-day course on lung ultrasound [LU] and performance of 10 diaphragm ultrasounds [DUs] under supervision), and a more-trained examiner (completion of a 1-day course on LU and performance of 60 DUs under supervision).

RESULTS

Two groups of 33 TN and 33 PTN were studied. Median DSF values did not differ between the groups, although diaphragm thickness was higher in the TN group. Intra-observer reproducibility: the intraclass correlation coefficient (ICC) was 0.95 (95% confidence interval [95% CI] 0.86-0.98). Interobserver reproducibility with novel operator had an ICC of 0.42 (95% CI -0.74 to 0.81), and with a more experienced operator improved to 0.76 (95% CI 0.27-0.92). Both intra- and interobserver agreement were high.

CONCLUSIONS

Asymptomatic TN and PTN have similar DSF values in the first 24 hours of life. The intra- and interobserver agreement is high. Reproducibility is acceptable, but intensive training is necessary to perform adequate DU.

[Heart murmur in children less than 2 years-old: looking for a safe and effective referral strategy]

INTRODUCTION

Current guidelines in Spain recommend performing transthoracic echocardiography (TTE) in all children under 2 years of age with a heart murmur. In 2014, the American Paediatric Association published the first appropriate use criteria (AUC) for outpatient paediatric transthoracic echocardiography (TTE) to promote its cost-efficient use. The aim of this article is to analyse the AUC and other clinical factors as predictors of congenital heart disease (CHD) in children less than 2 years of age with a heart murmur, and to develop a safe and efficient referral strategy.

PATIENTS AND METHOD

Case-control study conducted with children less than 2 years of age, referred from Paediatric Primary Care to Paediatric Cardiology during a 4-year study. A predictive model for CHD was determined using multivariate analysis.

RESULTS

A total of 688 patients were included, with 129 (19%) cases of CHD. An age less than 3 months (adjusted odds ratio [ORa] 3.8 [1.5-8.4], p=.030) and fulfilling AUC (ORa 16.3 [9.4-28.3], p<.001) were predictors of CHD. Concurrent infection (ORa 0.6 [0.2-0.8], p<.001) and a negative neonatal screening with pulse oximetry (ORa 0.1 [0.05-0.4], p=.001) decreased the risk of CHD. The referral strategy that included these criteria had a 98% sensitivity, 39% specificity, and positive and negative predictive values of 27% and 99%, respectively. It could not diagnose 2% of CHD (all mild), and showed a 32% TTE reduction rate compared to our current strategy.

CONCLUSION

To refer children less than 3 months old, fulfilling AUC, without a concurrent infection, or without negative neonatal pulse oximetry screening, is a safe and efficient strategy for the management of heart murmur in children under 2 years of age.