Lung ultrasound findings in pediatric community-acquired pneumonia requiring surgical procedures: a two-center prospective study

Parapneumonic empyema in children: a scoping review of the literature

Community-acquired pneumonia can lead to a serious complication called empyema, which refers to pus within the pleural space. While it poses a significant threat to morbidity, particularly in children, it is fortunately not associated with high mortality rates. However, determining the best course of management for children, including decisions regarding antibiotic selection, administration methods, and treatment duration, remains a topic of ongoing debate. This scoping review aims to map the existing literature on empyema in children, including types of studies, microbiology, therapies (both antimicrobial and surgical) and patient outcomes. We systematically searched PubMed and SCOPUS using the terms "pediatric" (encompassing children aged 0 to 18 years) and "pleural empyema" to identify all relevant studies published since 2000. This search adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA ScR) checklist.A total of 127 studies was included. Overall, 15 attempted to compare medical treatments (alone or in combination with pleural drainage or fibrinolysis) with more invasive surgical approaches, and six studies compared diverse surgical interventions. However, the diversity of study designs makes it difficult to derive firm conclusions on the optimal approach to pediatric empyema. The heterogeneity in inclusion criteria, pharmacological/surgical approaches and settings limit the ability to draw definitive conclusions. Overall, 78 out of 10,896 children (0.7%) included in the review died, with mortality being higher in Asia and Africa. Our scoping review highlights important gaps regarding several aspects of empyema in children, including specific serotypes of the most common bacteria involved in the etiology, the optimal pharmacological and surgical approach, and the potential benefits of newer antibiotics with optimal lung penetration. New trials, designed on a multi-country level a higher number of patients and more rigorous inclusion criteria and designs, should be urgently funded.

Lung ultrasound evaluation in people with cystic fibrosis: A new approach in the pulmonology outpatient clinic

BACKGROUND

Cystic fibrosis (CF) is a genetic disease that causes progressive lung disease with major impact on the quality of life. Lung ultrasound (LUS) allows to assess the lung involvement through the artefacts analysis and is increasingly used in children but is not yet used to monitor people with CF(pwCF). The main aim of this study was to describe the LUS pattern of pwCF during their routinary check-up visit. The secondary objective was to correlate the LUS findings with pulmonary function indices.

METHODS

We performed a cross-sectional observational study, enrolling adolescents and young adults with CF. Each patient underwent clinical assessment, measurement of SpO2, assessment of lung function by spirometry and LUS.

RESULTS

Twenty-nine subjects with CF were included. The most frequent alterations were consolidations (72.4%) located in the left apical anterior and right apical posterior regions followed by interstitial syndrome (65.5%). The 41.4% of cases presented the lingula involvement, characterized by a consolidation with static air bronchogram, and 55.2% showed pleural irregularity mainly in the posterior apical regions. A significant correlation was found between the LUS total score and spirometric indices: FEV1 (p = .003), FVC (p = .002), Tiffenau Index <80% (p = .014), and FEF 25-75 (p = .004).

CONCLUSIONS

Our study describes LUS findings in pwCF. It also showed a correlation between LUS score and the patients' lung function measured by spirometric indices. We conclude that LUS may be useful in routine monitoring of pwCF in combination with clinical and spirometric assessment.

Lung ultrasound: A potential tool in the diagnosis of ventilator-associated pneumonia in pediatric intensive care units

PURPOSE

Ventilator-associated pneumonia (VAP) is a common healthcare-associated infection in pediatric intensive care unit (PICU), increasing mortality, antibiotics use and duration of ventilation and hospitalization. VAP diagnosis is based on clinical and chest X-ray (CXR) signs defined by the 2018 Center for Disease Control (gold standard). However, CXR induces repetitive patients' irradiation and technical limitations. This study aimed to investigate if lung ultrasound (LUS) can substitute CXR in the VAP diagnosis.

METHODS

A monocentric and prospective study was conducted in a French tertiary care hospital. Patients under 18-year-old admitted to PICU between November 2018 and July 2020 with invasive mechanical ventilation for more than 48 h were included. The studied LUS signs were consolidations, dynamic air bronchogram, subpleural consolidations (SPC), B-lines, and pleural effusion. The diagnostic values of each sign associated with clinical signs (cCDC) were compared to the gold standard approach. LUS, chest X-ray, and clinical score were performed daily.

RESULTS

Fifty-seven patients were included. The median age was 8 [3-34] months. Nineteen (33%) children developed a VAP. In patients with VAP, B-Lines, and consolidations were highly frequent (100 and 68.8%) and, associated with cCDC, were highly sensitive (100 [79-100] % and 88 [62-98] %, respectively) and specific (95.5 [92-98] % and 98 [95-99] %, respectively). Other studied signs, including SPC, showed high specificity (>97%) but low sensibility (<50%).

CONCLUSION

LUS seems to be a powerful tool for VAP diagnosis in children with a clinical suspicion, efficiently substituting CXR, and limiting children's exposure to ionizing radiations.

Use of POCUS for the assessment of dehydration in pediatric patients-a narrative review

In pediatric practice, POCUS (point-of-care ultrasound) has been mostly implemented to recognize lung conditions and pleural and pericardial effusions, but less to evaluate fluid depletion. The main aim of this review is to analyze the current literature on the assessment of dehydration in pediatric patients by using POCUS. The size of the inferior vena cava (IVC) and its change in diameter in response to respiration have been investigated as a tool to screen for hypovolemia. A dilated IVC with decreased collapsibility (< 50%) is a sign of increased right atrial pressure. On the contrary, a collapsed IVC may be indicative of hypovolemia. The IVC collapsibility index (cIVC) reflects the decrease in the diameter upon inspiration. Altogether the IVC diameter and collapsibility index can be easily determined, but their role in children has not been fully demonstrated, and an estimation of volume status solely by assessing the IVC should thus be interpreted with caution. The inferior vena cava/abdominal aorta (IVC/AO) ratio may be a suitable parameter to assess the volume status in pediatric patients even though there is a need to define age-based thresholds. A combination of vascular, lung, and cardiac POCUS could be a valuable supplementary tool in the assessment of dehydration in several clinical scenarios, enabling rapid identification of life-threatening primary etiologies and helping physicians avoid inappropriate therapeutic interventions.   Conclusion: POCUS can provide important information in the assessment of intravascular fluid status in emergency scenarios, but measurements may be confounded by a number of other clinical variables. The inclusion of lung and cardiac views may assist in better understanding the patient's physiology and etiology regarding volume status. What is Known: • In pediatric practice, POCUS (point-of-care ultrasound) has been mostly implemented to recognize lung conditions (like pneumonia and bronchiolitis) and pleural and pericardial effusions, but less to evaluate fluid depletion. • The size of the IVC (inferior vena cava) and its change in diameter in response to respiration have been studied as a possible screening tool to assess the volume status, predict fluid responsiveness, and assess potential intolerance to fluid loading. What is New: • The IVC diameter and collapsibility index can be easily assessed, but their role in predicting dehydration in pediatric age has not been fully demonstrated, and an estimation of volume status only by assessing the IVC should be interpreted carefully. • The IVC /AO(inferior vena cava/abdominal aorta) ratio may be a suitable parameter to assess the volume status in pediatric patients even though there is a need to define age-based thresholds. A combination of vascular, lung, and cardiac POCUS can be a valuable supplementary tool in the assessment of intravascular volume in several clinical scenarios.

The utility of chest x-ray and lung ultrasound in the management of infants and children presenting with severe pneumonia in low-and middle-income countries: A pragmatic scoping review

Background

Chest x-ray (CXR) is commonly used (when available) to support clinical management decisions for child pneumonia and provide a reference standard for diagnosis in research studies. However, its diagnostic and technical limitations for both purposes are well recognised. Recent evidence suggests that lung ultrasound (LUS) may have diagnostic utility in pneumonia. This systematic scoping review of research on the utility of CXR and LUS in the management of severe childhood pneumonia aims to inform pragmatic guidelines for low- and middle-income countries (LMICs) and identify gaps in knowledge.

Methods

We included peer-reviewed studies published between 2000 and 2020 in infants and children aged from one month to nine years, presenting with severe pneumonia. CXR studies were limited to those from LMICs, while LUS studies included any geographic region. LUS and CXR articles were mapped into the following themes: indications, role in diagnosis, role in management, impact on outcomes, and practical considerations for LMIC settings.

Results

85 articles met all eligibility criteria, including 27 CXR studies and 58 LUS studies. CXR studies were primarily observational and examined associations between radiographic abnormalities and pneumonia aetiology or outcomes. The most consistent finding was an association between CXR consolidation and risk of mortality. Difficulty obtaining quality CXR images and inter-reader variability in interpretation were commonly reported challenges. Research evaluating indications for CXR, role in management, and impact on patient outcomes was very limited. LUS studies primarily focused on diagnostic accuracy. LUS had higher sensitivity for identification of consolidation than CXR. There are gaps in knowledge regarding diagnostic criteria, as well as the practical utility of LUS in the diagnosis and management of pneumonia. Most LUS studies were conducted in HIC settings with experienced operators; however, small feasibility studies indicate that good inter-operator reliability may be achieved by training of novice clinicians in LMIC settings.

Conclusions

The available evidence does not support the routine use of CXR or LUS as essential tools in the diagnosis and initial management of severe pneumonia. Further evaluation is required to determine the clinical utility and feasibility of both imaging modalities in low-resource settings.

Are Lung Ultrasound Features More Severe in Children Diagnosed with Bronchiolitis after the COVID-19 Lockdown Period?

The non-pharmacological measures implemented during the SARS-CoV-2 pandemic disrupted the usual bronchiolitis seasonality. Some authors have speculated that, after the lock down period, there would be an increase in the number and severity of respiratory infections due to the re-introduction of respiratory viruses. We collected clinical, microbiological and lung ultrasound data using the classification of the Italian Society of Thoracic Ultrasound (ADET) in children with bronchiolitis during the pandemic compared to the pre-pandemic period, with the aim of assessing whether the epidemic of bronchiolitis during the pandemic was characterized by a more severe lung involvement documented by lung ultrasound. We enrolled 108 children with bronchiolitis (52 pre-pandemic and 56 COVID-19 period), with a median age of 1.74 months (interquartile range, IQR 1-3.68) and 39.8% were females. Rhinovirus detection and high-flow nasal cannula usage were both increased during the COVID-19 period, although overall need of hospitalization and pediatric intensive care unit admissions did not change during the two periods. Lung ultrasound scores were similar in the two cohorts evaluated. Conclusions: our study suggests that, despite changes in microbiology and treatments performed, lung ultrasound severity scores were similar, suggesting that that bronchiolitis during the pandemic period was no more severe than pre-pandemic period, despite children diagnosed during the pandemic had a higher, but it was not statistically significant, probably, due to small sample size, probability of being admitted.

Prognostic Role of Lung Ultrasound in Children with Bronchiolitis: Multicentric Prospective Study

There is increasing recognition of the role of lung ultrasound (LUS) to assess bronchiolitis severity in children. However, available studies are limited to small, single-center cohorts. We aimed to assess a qualitative and quantitative LUS protocol to evaluate the course of bronchiolitis at diagnosis and during follow-up. This is a prospective, multicenter study. Children with bronchiolitis were stratified according to clinical severity and underwent four LUS evaluations at set intervals. LUS was classified according to four models: (1) positive/negative; (2) main LUS pattern (normal/interstitial/consolidative/mixed) (3) LUS score; (4) LUS score with cutoff. Two hundred and thirty-three children were enrolled. The baseline LUS was significantly associated with bronchiolitis severity, using both the qualitative (positive/negative LUS p < 0.001; consolidated/normal LUS pattern or mixed/normal LUS p < 0.001) and quantitative models (cutoff score > 9 p < 0.001; LUS mean score p < 0.001). During follow-up, all LUS results according to all LUS models improved (p < 0.001). Better cut off value was declared at a value of >9 points. Conclusions: Our study supports the role of a comprehensive qualitative and quantitative LUS protocol for the identification of severe cases of bronchiolitis and provides data on the evolution of lung aeration during follow-up.

Lung Ultrasound Artifact Findings in Pediatric Patients Admitted to the Intensive Care Unit for Acute Respiratory Failure

PURPOSE

To describe point-of-care lung ultrasound (POC-LUS) artifact findings in children admitted to the pediatric intensive care unit (PICU) for acute respiratory failure (ARF).

METHODS

This is a secondary analysis of a prospective observational study completed in a 21-bed PICU. Children > 37 weeks gestational age and ≤ 18 years were enrolled from December 2018 to February 2020. POC-LUS was completed and interpreted by separate physicians blinded to all clinical information. POC-LUS was evaluated for the presence of lung sliding, pleural line characteristics, ultrasound artifacts, and the ultrasound diagnosis.

RESULTS

Eighty-seven subjects were included. A-lines were the most frequent artifact, occurring in 58% of lung zones (163/281) in those with bronchiolitis, 39% of lung zones (64/164) in those with pneumonia, and 81% of lung zones (48/59) in those with status asthmaticus. Sub-pleural consolidation was second most common, occurring in 28% (80/281), 30% (50/164), and 12% (7/59) of those with bronchiolitis, pneumonia, and status asthmaticus, respectively. The pattern a priori defined as bronchiolitis, pneumonia, and status asthmaticus was demonstrated in 31% (15/48), 10% (3/29), and 40% (4/10) of subjects with bronchiolitis, pneumonia, and status asthmaticus, respectively.

CONCLUSION

We found significant heterogeneity and overlap of POC-LUS artifacts across the most common etiologies of ARF in children admitted to the PICU. We have described the POC-LUS artifact findings in pediatric ARF to support clinicians using POC-LUS and to guide future pediatric POC-LUS studies. Determining the optimal role of POC-LUS as an adjunct in the care of pediatric patients requires further study.

Comparison of pediatric empyema secondary to tuberculosis or non-tuberculosis community-acquired pneumonia in those who underwent surgery in high TB burden areas

INTRODUCTION

Tuberculous empyema (TE) in children is common in high-TB burden and medical resource-limited areas. However, studies that evaluate the characteristics of TE in children are sparse. This study aimed to analyze the clinical features of pediatric TE receiving surgical intervention.

METHODS

We performed a retrospective study of children with empyema secondary to community-acquired pneumonia who underwent surgery in our institution. The clinical characteristics were compared between TE and empyema secondary non-tuberculosis infection (non-tuberculosis empyema, NTE).

RESULTS

One hundred patients were included (27 with TE and 73 with NTE). Stage 3 empyema occupied 81.5% and 45.2% of TE and NTE in this study. The TE children had older age, longer duration of illness, and milder symptoms. Pleural fluid culture was positive for Mycobacterium tuberculosis in 7.4% of patients with TE. Lymph node enlargement, lymph node calcification, and pleural nodules presented in TE with high specificity (93.2%, 98.6%, and 98.5%) but low sensitivity (33.3%, 14.8%, and 29.6%) on CT scan. Thoracoscopy surgery was performed in 14 (51.9%) in TE and 39 (53.4%) in NTE. Postoperative chest-tube indwelling time was longer (7.85 ± 5.00 vs. 4.89 ± 1.81 days, p < .001), and more patients had incomplete lung expansion after 3 months in TE.

CONCLUSION

Tuberculosis infection should be screened in management of children with empyema in high-TB burden areas. Pediatric TE usually presented at older age and with milder respiratory symptoms. Pleural biopsy during surgery is often necessary to confirm the cause of infection. Thoracotomy is still required in some pediatric TE or NTE with delayed treatment in medical resource-limited area.

Classification of Lung Disease in Children by Using Lung Ultrasound Images and Deep Convolutional Neural Network

Bronchiolitis is the most common cause of hospitalization of children in the first year of life and pneumonia is the leading cause of infant mortality worldwide. Lung ultrasound technology (LUS) is a novel imaging diagnostic tool for the early detection of respiratory distress and offers several advantages due to its low-cost, relative safety, portability, and easy repeatability. More precise and efficient diagnostic and therapeutic strategies are needed. Deep-learning-based computer-aided diagnosis (CADx) systems, using chest X-ray images, have recently demonstrated their potential as a screening tool for pulmonary disease (such as COVID-19 pneumonia). We present the first computer-aided diagnostic scheme for LUS images of pulmonary diseases in children. In this study, we trained from scratch four state-of-the-art deep-learning models (VGG19, Xception, Inception-v3 and Inception-ResNet-v2) for detecting children with bronchiolitis and pneumonia. In our experiments we used a data set consisting of 5,907 images from 33 healthy infants, 3,286 images from 22 infants with bronchiolitis, and 4,769 images from 7 children suffering from bacterial pneumonia. Using four-fold cross-validation, we implemented one binary classification (healthy vs. bronchiolitis) and one three-class classification (healthy vs. bronchiolitis vs. bacterial pneumonia) out of three classes. Affine transformations were applied for data augmentation. Hyperparameters were optimized for the learning rate, dropout regularization, batch size, and epoch iteration. The Inception-ResNet-v2 model provides the highest classification performance, when compared with the other models used on test sets: for healthy vs. bronchiolitis, it provides 97.75% accuracy, 97.75% sensitivity, and 97% specificity whereas for healthy vs. bronchiolitis vs. bacterial pneumonia, the Inception-v3 model provides the best results with 91.5% accuracy, 91.5% sensitivity, and 95.86% specificity. We performed a gradient-weighted class activation mapping (Grad-CAM) visualization and the results were qualitatively evaluated by a pediatrician expert in LUS imaging: heatmaps highlight areas containing diagnostic-relevant LUS imaging-artifacts, e.g., A-, B-, pleural-lines, and consolidations. These complex patterns are automatically learnt from the data, thus avoiding hand-crafted features usage. By using LUS imaging, the proposed framework might aid in the development of an accessible and rapid decision support-method for diagnosing pulmonary diseases in children using LUS imaging.

Lung ultrasound may support internal medicine physicians in predicting the diagnosis, bacterial etiology and favorable outcome of community-acquired pneumonia

To assess the usefulness of lung ultrasound (LUS) for identifying community-acquired pneumonia (CAP) among adult patients with suspected lower respiratory tract infection (LRTI) and for discriminating between CAP with different cultural statuses, etiologies, and outcomes. LUS was performed at internal medicine ward admission. The performance of chest X-ray (CXR) and LUS in diagnosing CAP in 410 patients with suspected LRTI was determined. All possible positive results for pneumonia on LUS were condensed into pattern 1 (consolidation + / − alveolar-interstitial syndrome) and pattern 2 (alveolar-interstitial syndrome). The performance of LUS in predicting culture-positive status, bacterial etiology, and adverse outcomes of CAP was assessed in 315 patients. The area under the receiver operating characteristic curve for diagnosing CAP by LUS was significantly higher than for diagnosis CAP by CXR (0.93 and 0.71, respectively; p < 0.001). Pattern 1 predicted CAP with bacterial and mixed bacterial and viral etiologies with positive predictive values of 99% (95% CI, 94–100%) and 97% (95% CI, 81–99%), respectively. Pattern 2 ruled out mortality with a negative predictive value of 95% (95% CI, 86–98%), respectively. In this study, LUS was useful in predicting a diagnosis of CAP, the bacterial etiology of CAP, and favorable outcome in patients with CAP.

Lung ultrasound to predict pediatric intensive care admission in infants with bronchiolitis (LUSBRO study)

It is extremely difficult to stratify bronchiolitis and predict the need for admission to the pediatric intensive care unit (PICU). We aimed to evaluate the capacity of a new lung ultrasound score (LUSBRO) to predict the need for admission to the PICU compared to a clinical score. This was a prospective observational single-center study that includes infants < 6 month of age admitted to a hospital due to acute bronchiolitis. Both scores were calculated at admission. The main outcome was PICU admission. Second endpoints were the need for mechanical ventilation, respiratory support duration, and the length of stay in the hospital. Eighty patients were included, with a median age of 53 days (IQR 29-115). Forty-four patients (55%) required PICU admission. LUSBRO score showed a better AUC compared to the clinical score to predict PICU admission: 0.932 (95% CI 0.873-0.990) vs. 0.675 (95% CI 0.556-0.794) and a positive correlation with the hospital length of stay. The best cut-off point for predicting the need for PICU admission for LUSBRO score was 6, showing a sensitivity of 90.91% and a specificity of 88.89%.Conclusions: The LUSBRO score is a useful tool to predict the need for admission to the PICU. What is Known • It is extremely difficult to stratify which patients affected by bronchiolitis should be precociously transferred to a third level hospital and will require pediatric intensive care unit (PICU) admission. • Clinical scores have been created but neither of them is accurate. What is New • The LUSBRO score is a useful tool to predict the need for admission to the PICU of patients with bronchiolitis and, consequently, to predict the patients who should be transferred to a tertiary hospital to optimize respiratory support.

Contrast-Enhanced Ultrasound of the Pleural Cavity: A Method to Locate Pleural Catheters and Identify Fibrous Septa

We aimed to explore the value of contrast-enhanced ultrasound (CEUS) of the pleural cavity in locating catheters and identifying fibrous septa and to compare CEUS with multiple existing methods. We included 304 participants whose pleural effusion could not continue to be drained and compared the catheter-localization capabilities of empirical diagnosis, B-mode ultrasound with normal saline and CEUS, with computed tomography as the reference standard. CEUS performed the best (accuracy, 100%; sensitivity, 100%; specificity, 100%), followed by B-mode ultrasound with normal saline (accuracy, 77.78%; sensitivity, 62.5%; specificity, 100%), and finally empirical diagnosis (accuracy, 54.17%; sensitivity, 66.67%; specificity, 33.33%). The capabilities of CEUS and computed tomography to identify fibrous septa were evaluated, with B-mode ultrasound as the reference, and CEUS (accuracy, 100%; sensitivity, 100%; specificity, 100%) was superior to computed tomography (accuracy, 82.41%; sensitivity, 26.09%; specificity, 97.65%). Overall, CEUS can accurately locate catheters and identify fibrous septa, with performance superior to existing methods.