Long-Term Outcome of Surgically Repaired and Non-repaired Double Aortic Arch in Children.

Introduction A double aortic arch (DAA) is a rare congenital vascular anomaly that encircles the trachea and esophagus, resulting in compression of both structures and causing variable symptoms of wheezing, stridor, increased work of breathing, or dysphagia. DAA usually presents in infancy but can be incidentally found later in life. The standard management of DAA is surgical repair. However, observation and follow-up have been recommended in asymptomatic or mild cases. The long-term outcome of surgical repair versus observation is not well-reported. We described the long-term clinical outcome of patients with DAA who were surgically repaired versus non-repaired at our institution.  Methods Electronic medical records were searched for the patients diagnosed with DAA before the age of 18 years. Data from clinical, radiological, and bronchoscopic findings, pulmonary function test (PFT), and cardiopulmonary exercise testing (CPET) were extracted. A structured phone questionnaire of patients' parents regarding past and current symptoms was also conducted. Results A total of 12 patients (eight males four females) with DAA were identified. Median age was 8.5 (1.5-17) years. The age at diagnosis was 60 (1-192) months. Post diagnosis follow-up period was 20 (2-156) months. Five patients were surgically repaired, and seven patients were not repaired. The median age of surgery was five (1-15) years in repaired patients. The phone questionnaire was completed in only 10 patients (five repaired and five non-repaired). Respiratory symptoms in infancy were reported in all repaired and non-repaired patients and were resolved in all five repaired patients and in four of the five non-repaired patients. One non-repaired patient complained of intermittent dyspnea on exertion. Gastrointestinal symptoms were present in infancy in three repaired and three non-repaired patients and were improved in two repaired and one non-repaired patient. PFT was performed in five patients (one repaired, four non-repaired) and showed normal forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC in all patients. Low peak expiratory flow (PEF) was seen in the repaired patient and in three of the non-repaired patients. CPET was conducted in four non-repaired patients and showed maximal oxygen consumption (VO2-max) of 66% predicted (58-88), maximal ventilation (VE-max) of 75% predicted (70-104), and ventilatory reserve of 55% predicted (48-104).  Conclusion Long-term clinical outcome is favorable in both repaired and non-repaired patients with DAA even though both groups reported respiratory symptoms during infancy. Therefore, clinical observation is a legitimate option in certain DAA patients.

Impact of COVID­19 pandemic restrictions and subsequent relaxation on the prevalence of respiratory virus hospitalizations in children.

BACKGROUND: The COVID-19 pandemic and the consequently adopted worldwide control measures have resulted in global changes in the epidemiology and severity of other respiratory viruses. We compared the number and severity of viral acute lower respiratory tract infection (ALRTI) hospitalizations and determined changes in causative respiratory pathogens before, during, and after the pandemic among young children in Qatar. METHODS: In this single-center retrospective study, we reviewed data of children ≤ 36 months old who were admitted to Sidra Medicine in Qatar with a viral ALRTI during winter seasons (September-April) between 2019 and 2023. The study period was divided into three distinct seasons based on the pandemic-imposed restrictions as follows: (1) the period between September 2019 and April 2020 was considered the pre-COVID-19 pandemic season; (2) the periods between September 2020 and April 2021, and the period between January and April 2022 were considered the COVID-19 pandemic seasons; and (3) the periods between September 2022 and April 2023 was considered the post-COVID-19 pandemic season. RESULTS: During the COVID-19 season, 77 patients were admitted, compared with 153 patients during the pre-COVID-19 season and 230 patients during the post-COVID-19 season. RSV was the dominant virus during the pre-COVID-19 season, with a detection rate of 50.9%. RSV infection rate dropped significantly during the COVID-19 season to 10.4% and then increased again during the post-COVID-19 season to 29.1% (P < 0.001). Rhinovirus was the dominant virus during the COVID-19 (39.1%) and post-COVID-19 seasons (61%) compared to the pre-COVID-19 season (31.4%) (P < 0.001). The average length of hospital stay was significantly longer in the post-COVID-19 season than in the pre-COVID-19 and COVID-19 seasons (P < 0.001). No significant differences in the pediatric intensive care unit (PICU) admission rate (P = 0.22), PICU length of stay (p = 0.479), or respiratory support requirements were detected between the three seasons. CONCLUSION: Our study showed reduced viral ALRTI hospitalizations in Qatar during the COVID-19 pandemic with reduced RSV detection. An increase in viral ALRTI hospitalizations accompanied by a resurgence of RSV circulation following the relaxation of COVID-19 restrictions was observed without changes in disease severity.

Prevalence of Sleep-Disordered Breathing in Prader-Willi Syndrome.

Introduction: Sleep-disordered breathing (SDB) is common in patients with Prader-Willi Syndrome (PWS). However, the prevalence of SDB varies widely between studies. Early identification of SDB and factors contributing to its incidence is essential, particularly when considering growth hormone (GH) therapy. Objectives: The aims of the study were to describe the prevalence and phenotypes of sleep-disordered breathing (SDB) in patients with Prader-Willi syndrome (PWS) and to determine the effects of age, gender, symptoms, GH therapy and body mass index on SDB severity. Methods: This study was a retrospective chart review of all patients with genetically confirmed Prader-Willi syndrome who underwent diagnostic overnight polysomnography (PSG) in the sleep laboratory at Sidra Medicine. Clinical and PSG data of enrolled patients were collected. Results: We identified 20 patients (nine males, eleven females) with PWS who had overnight sleep polysomnography (PSG) at a median age (IQR) of 5.83 (2.7-12) years. The median apnea-hypopnea index (AHI) was 8.55 (IQR 5.8-16.9) events/hour. The median REM-AHI was 27.8 (IQR 15-50.6) events/hour. The median obstructive apnea-hypopnea index (OAHI) was 7.29 (IQR 1.8-13.5) events/hour. The median central apnea-hypopnea index (CAHI) was 1.77 (IQR 0.6-4.1) events/hour. Nineteen patients (95%) demonstrated SDB by polysomnography (PSG) based on AHI ≥1.5 events/hour. Nine patients (45%) were diagnosed with obstructive sleep apnea (OSA). Three patients (15%) were diagnosed with central sleep apnea (CSA). Seven patients (35%) were diagnosed with mixed sleep apnea. No correlations were observed between AHI and age, gender, BMI, symptoms, or GH therapy. However, REM-AHI was significantly correlated with BMI (P=0.031). Conclusion: This study shows a high prevalence of SDB among our patients with PWS. Obstructive sleep apnea was the predominant phenotype. BMI was the only predictor for high REM-AHI. Further studies of large cohorts are warranted to define SDB in PWS and design the appropriate treatment.

Drug Reaction with Eosinophilia and Systemic Symptoms Syndrome in a Child with Cystic Fibrosis.

Background: Drug reaction with eosinophilia and systemic symptoms (DRESSs) syndrome is an idiosyncratic drug-induced reaction that rarely occurs in children but can lead to serious complications. It manifests most commonly with fever, extensive skin eruptions, and eosinophilia. Symptoms typically develop two to six weeks after the initiation of the inciting drug. Visceral organ involvement especially the liver can also occur and if not recognized early and the inciting drug is not stopped immediately, it can lead to liver failure. Therefore, early diagnosis is important but can be very challenging because of disease rarity, lack of a diagnostic test, and its overlap with other common pediatric allergic and infectious conditions. Case Presentation. A 2.5-year-old boy with known diagnosis of cystic fibrosis, bilateral bronchiectasis, pancreatic insufficiency, and chronic airway colonization with Pseudomonas aeruginosa was admitted to our hospital with acute pulmonary exacerbation of CF lung disease. He was treated with intravenous piperacillin-tazobactam and intravenous amikacin in addition to airway clearance. On day 18 of treatment, the patient developed high grade fever followed by diffuse erythematous and pruritic maculopapular rash. Blood tests showed high eosinophilia, high C-reactive protein (CRP), and high liver enzymes levels. The clinical features and the laboratory findings were consistent with the DRESS syndrome. Therefore, all antibiotics were discontinued. Progressive resolution of the symptoms was observed within two days. Laboratory abnormalities were also normalized in the follow-up clinic visit 4 months later. Conclusion: Our case demonstrates the importance of early recognition of the DRESS syndrome in children who develop fever and skin rashes with eosinophilia while undergoing long-term antibiotic treatment. Prompt discontinuation of the offending drug is the cornerstone therapy and results in the resolution of symptoms and prevention of serious complications.

A breakthrough effect of gene replacement therapy on respiratory outcomes in children with spinal muscular atrophy.

INTRODUCTION: Spinal muscular atrophy (SMA) is an inherited progressive neuromuscular disorder characterized by generalized hypotonia, respiratory failure and early death. The introduction of gene replacement therapy (GRT) modified the natural history of the disease. However, more data is needed to understand the long-term effect of GRT on measurable respiratory outcomes. We report the respiratory outcomes in our cohort of patients with SMA post-GRT in 2-year period. METHODS: A retrospective chart-review of genetically confirmed children with SMA who received GRT between 2019 and 2021 in Qatar. The evaluated respiratory outcomes were chronic respiratory support, respiratory hospitalizations, escalation of respiratory support and polysomnography results before and after GRT. Nonrespiratory outcomes; nutritional status, swallowing, and motor functions; were also assessed. RESULTS: A total of 11 patients (9 patients with SMA-1 and 2 patients with SMA-2) received GRT at a median age of 12 months and 22 months in patients with SMA-1 and SMA-2, respectively. All patients were successfully weaned off Noninvasive ventilation (NIV) except one patient who remained on mechanical ventilation through tracheostomy tube. The annualized hospitalization rate dropped by half after GRT. The average length of stay (LOS) in intensive care unit (ICU) decreased by 17.32 days/patient/year after GRT. Duration of required escalation of respiratory support during acute hospitalizations has dropped by 18.56 days/patient/year post-GRT. CONCLUSION: We report favorable respiratory outcomes of GRT in our cohort. GRT resulted in discontinuation of chronic respiratory support in majority of ventilated patients. GRT also resulted in decreased respiratory hospitalization rate, hospital-LOS, ICU-LOS, and need for escalation of ventilatory support.

Successful management of congenital bronchial web in an adolescent using bronchoscopic ablation: A case report and review of literature.

Airway webs are abnormal fibrous membranes in the airway lumen that rarely occur but can lead to serious or even life-threatening symptoms because of critical airway obstruction. Airway webs can be acquired or congenital. Acquired webs are likely to be secondary to trauma, infections, or neoplasm. Congenital laryngeal, subglottic and tracheal webs present early in infancy or childhood and are more common than congenital bronchial webs. To our knowledge, there are a few reports on the bronchial web in the literature, and the true incidence of these lesions is unknown as many probably go undetected across the lifespan. We here report a case of a congenital bronchial web and provide a review of the literature of all reported bronchial webs. Our patient is a teenage boy who was diagnosed with a congenital bronchial web obstructing the right main-stem bronchus (RMB) and causing right lung hypoplasia and persistent right middle and right lower lobe collapse. The web was treated successfully using endoscopic ablation by argon plasma coagulation and balloon dilatation. Treatment resulted in remarkable relief of right main stem obstruction and significant improvement in right lung collapse as well as clinical, spirometric, and radiological findings. Due to the rarity of bronchial web, the clinical knowledge and the bronchoscopic interventional strategies demonstrated of this report make it relevant. Furthermore, it emphasizes that early diagnosis and management lead to favorable clinical outcomes.

Use of Intravenous Pulse Steroids to Treat Allergic Bronchopulmonary Aspergillosis in a Non-Compliant Asthmatic Adolescent.

Allergic bronchopulmonary aspergillosis (ABPA) is an immune-mediated inflammatory airway disease that predominantly affects patients with cystic fibrosis (CF) and, less commonly, patients with asthma. ABPA can lead to irreversible lung injury and bronchiectasis if not treated early and aggressively. Long-term oral steroids are the standard therapy of ABPA. However, it is associated with an increased risk of steroids side effects and possible medication noncompliance. Monthly intravenous pulse methylprednisolone (IV-PS) has been used as an alternative to oral steroids to treat CF-related ABPA with a reportedly similar clinical response and less steroid-related side effects. To our knowledge, the use of IV-PS in asthma-related ABPA has not been previously reported. We report the successful management of asthma-related ABPA in an adolescent using intravenous pulse methylprednisolone in addition to oral itraconazole with no significant steroid-related side effects.

Pleuropulmonary Blastoma (PPB) in Child with DICER1 Mutation: The First Case Report in the State of Qatar.

Pleuropulmonary blastoma (PPB) is a rare intrathoracic malignancy, which arises from the lung parenchyma and/or pleura. PPB has strong genetic association with mutations in DICER1 gene. Despite being rare, PPB is the most common lung tumor in children below 6 years of age. International registry of the disease has a total of 350 cases worldwide. We report the first case of PPB in the state of Qatar, which presented as a large cystic lung lesion. The patient was first thought to have benign congenital pulmonary airway malformation (CPAM) based on chest X-ray findings. The diagnosis of PPB was suspected based on chest CT scan findings and was confirmed after surgical resection of the cystic mass. The case highlights the need to consider PPB in the differential diagnosis of cystic lung lesions in children and the need for further radiological imaging (i.e., CT scan), genetic testing, and/or excisional biopsy to confirm the diagnosis.

Using Mobile Health to Improve Asthma Self-Management in Early Adolescence: A Pilot Randomized Controlled Trial.

PURPOSE: Early adolescence is an important developmental period where youth take primary responsibility for asthma self-management. Helpful caregiver support during this time is pivotal in determining whether early adolescents successfully develop asthma self-management behaviors. AIM2ACT is a dyadic mobile health intervention designed to increase helpful caregiver support as early adolescents engage in asthma self-management behaviors. We conducted a pilot randomized controlled trial to determine the feasibility and acceptability of AIM2ACT and conduct preliminary tests of efficacy. METHODS: We randomized adolescents (12-15 years old) and a caregiver to receive AIM2ACT (n = 17) or a self-guided attention control condition (n = 16) for 20 weeks. We conducted assessment visits at baseline, postintervention, and 4-month follow-up. Outcomes included family asthma management (primary outcome), adolescent asthma control, lung function (forced expiratory volume in 1 second), asthma-related quality of life, asthma management self-efficacy, and family communication. RESULTS: We randomized 33 dyads and had 100% retention in the trial among AIM2ACT participants. Dyads frequently engaged with AIM2ACT (M = 21 days for adolescents, 32.65 days for caregivers) and reported very high satisfaction with content, functionality, and helpfulness. Participants randomized to AIM2ACT had significant improvements in asthma control scores (p = .04) compared to control that surpassed the minimally clinically important difference threshold. Although not statistically significant, the magnitude of improvements in family asthma management, asthma-related quality of life, and family communication was larger in the AIM2ACT group. CONCLUSIONS: AIM2ACT is a feasible and acceptable dyadic mobile health asthma self-management intervention that improves asthma control.

Can Pharmacokinetic Studies Assess the Pulmonary Fate of Dry Powder Inhaler Formulations of Fluticasone Propionate?

In the context of streamlining generic approval, this study assessed whether pharmacokinetics (PK) could elucidate the pulmonary fate of orally inhaled drug products (OIDPs). Three fluticasone propionate (FP) dry powder inhaler (DPI) formulations (A-4.5, B-3.8, and C-3.7), differing only in type and composition of lactose fines, exhibited median mass aerodynamic diameter (MMAD) of 4.5 µm (A-4.5), 3.8 µm (B-3.8), and 3.7 µm (C-3.7) and varied in dissolution rates (A-4.5 slower than B-3.8 and C-3.7). In vitro total lung dose (TLDin vitro) was determined as the average dose passing through three anatomical mouth-throat (MT) models and yielded dose normalization factors (DNF) for each DPI formulation X (DNFx = TLDin vitro,x/TLDin vitro,A-4.5). The DNF was 1.00 for A-4.5, 1.32 for B-3.8, and 1.21 for C-3.7. Systemic PK after inhalation of 500 µg FP was assessed in a randomized, double-blind, four-way crossover study in 24 healthy volunteers. Peak concentrations (Cmax) of A-4.5 relative to those of B-3.8 or C-3.7 lacked bioequivalence without or with dose normalization. The area under the curve (AUC0-Inf) was bio-IN-equivalent before dose normalization and bioequivalent after dose normalization. Thus, PK could detect differences in pulmonary available dose (AUC0-Inf) and residence time (dose-normalized Cmax). The differences in dose-normalized Cmax could not be explained by differences in in vitro dissolution. This might suggest that Cmax differences may indicate differences in regional lung deposition. Overall this study supports the use of PK studies to provide relevant information on the pulmonary performance characteristics (i.e., available dose, residence time, and regional lung deposition).

Continuous Albuterol With Benzalkonium in Children Hospitalized With Severe Asthma.

BACKGROUND AND OBJECTIVES: The albuterol dropper bottle used to prepare solutions for continuous nebulization contains the preservative benzalkonium chloride (BAC). BAC, by itself, has been shown to cause bronchospasm. We hypothesized that BAC would decrease the therapeutic efficacy of albuterol in patients with acute asthma exacerbations. METHODS: We performed a retrospective cohort study comparing the clinical outcomes of patients <18 years of age receiving continuous nebulized albuterol with and without BAC. For the primary end point (duration of continuous albuterol nebulization), we compared the 2 groups with Kaplan-Meier estimate of survival curves, conducted a log-rank test of difference, and adjusted for baseline characteristics using multivariable Cox regression. A P value <.05 was considered significant. RESULTS: A total of 477 patients were included in the analysis (236 exposed to BAC and 241 controls). The duration of continuous nebulization was significantly longer in the BAC group than in the control group (median of 9 vs 6 hours; 15.7% required continuous nebulization compared to 5.8% of controls at 24 hours). The control group was 79% more likely to stop continuous nebulization at any particular point in time (hazard ratio 1.79; 95% confidence interval: 1.45 to 2.22; P < .001) and 43% more likely to stop additional respiratory support (hazard ratio 1.43; 95% confidence interval: 1.16 to 1.75; P < .001). CONCLUSIONS: BAC is a functional albuterol antagonist associated with a longer duration of continuous albuterol nebulization treatment and additional respiratory support, suggesting that preservative-free albuterol formulations are safer for use in continuous nebulization.

Upper versus lower airway microbiome and metagenome in children with cystic fibrosis and their correlation with lung inflammation.

OBJECTIVE: Airways of children with cystic fibrosis (CF) harbor complex polymicrobial communities which correlates with pulmonary disease progression and use of antibiotics. Throat swabs are widely used in young CF children as a surrogate to detect potentially pathogenic microorganisms in lower airways. However, the relationship between upper and lower airway microbial communities remains poorly understood. This study aims to determine (1) to what extent oropharyngeal microbiome resembles the lung microbiome in CF children and (2) if lung microbiome composition correlates with airway inflammation. METHOD: Throat swabs and bronchoalveolar lavage (BAL) were obtained concurrently from 21 CF children and 26 disease controls. Oropharyngeal and lung microbiota were analyzed using 16S rRNA deep sequencing and correlated with neutrophil counts in BAL and antibiotic exposure. RESULTS: Oropharyngeal microbial communities clustered separately from lung communities and had higher microbial diversity (p < 0.001). CF microbiome differed significantly from non-CF controls, with a higher abundance of Proteobacteria in both upper and lower CF airways. Neutrophil count in the BAL correlated negatively with the diversity but not richness of the lung microbiome. In CF children, microbial genes involved in bacterial motility proteins, two-component system, flagella assembly, and secretion system were enriched in both oropharyngeal and lung microbiome, whereas genes associated with synthesis and metabolism of nucleic acids and protein dominated the non-CF controls. CONCLUSIONS: This study identified a unique microbial profile with altered microbial diversity and metabolic functions in CF airways which is significantly affected by airway inflammation. These results highlight the limitations of using throat swabs as a surrogate to study lower airway microbiome and metagenome in CF children.

Diagnostic value of spirometry vs impulse oscillometry: A comparative study in children with sickle cell disease.

BACKGROUND: Spirometry is conventionally used to diagnose airway diseases in children with sickle cell disease (C-SCD). However, spirometry is difficult for younger children to perform, is effort dependent, and it provides limited information on respiratory mechanics. Impulse oscillometry (IOS) is an effort-independent pulmonary function test (PFT), which measures total airway resistance (R5Hz) and reactance (AX). IOS could be advantageous without certain limitations of spirometry. AIM: To compare the accuracy of IOS vs spirometry in making the diagnosis of asthma and assessing age-related pulmonary changes in C-SCD. STUDY DESIGN: Retrospective chart review. SUBJECT SELECTION: Fifty-six C-SCD and thirty-six controls (asthmatics without SCD) followed at Penn State with PFTs obtained during the initial pulmonary evaluation. METHODOLOGY: We grouped C-SCD into asthmatics and non-asthmatics based on pre-referral diagnosis and compared PFTs between two groups. Receiver operating characteristic (ROC) curve analyses and machine learning tools (XGBoost and artificial neural network) were used to rank the spirometry and IOS measures based on their ability to predict a diagnosis of asthma. Robust linear regression was used to analyze association among height/age with various PFT measures. RESULTS: Both ROC and XGBoost indicated that FEF25-75 %, forced expiratory volume in 1 second (FEV1)/forced vital capacity, and R5Hz(%) were the top three predictors for asthma diagnosis. R5Hz(%) and AX had superior bronchodilator response (BDR) than FEV1. IOS parameters had significant association with height/age in C-SCD (possibly due to the stiff lungs) but not in controls. CONCLUSION: IOS had advantages over spirometry in C-SCD because it is feasible in early childhood, provides insights into the pulmonary mechanics, and is more sensitive to detect BDR.

Protocol for the Development of a Behavioral Family Lifestyle Intervention Supported by Mobile Health to Improve Weight Self-Management in Children With Asthma and Obesity.

BACKGROUND: Asthma is the most common chronic childhood illness and is a leading cause of emergency department visits in the United States. Obesity increases the risk of poor health outcomes, reduced quality of life, and increased health care expenditures among youth with asthma. Weight loss is crucial for improving asthma outcomes in children with obesity. Our study team developed the Childhood Health and Asthma Management Program (CHAMP), a 16-session behavioral family lifestyle intervention (BFI) for school-age children with asthma and obesity and evaluated CHAMP in a randomized controlled trial compared with attention control. There were medium effect sizes favoring CHAMP for changes in body mass index z-scores, asthma control, and lung function among completers (ie, those who attended ≥9 of 16 sessions). Despite high rates of satisfaction reported by families, attendance and trial attrition were suboptimal, which raised concerns regarding the feasibility of CHAMP. Qualitative feedback from participants indicated 3 areas for refinement: (1) a less burdensome intervention modality, (2) a more individually tailored intervention experience, and (3) that interventionists can better answer health-related questions. OBJECTIVE: We propose to improve upon our pilot intervention by developing the Mobile Childhood Health and Asthma Management Program (mCHAMP), a nurse-delivered BFI, delivered to individual families, and supported by a mobile health (mHealth) app. This study aims to (1) identify structural components of mCHAMP and (2) develop and test the usability of our mCHAMP app. METHODS: Participants will be recruited from an outpatient pediatric pulmonary clinic. We will identify the structural components of mCHAMP by conducting a needs assessment with parents of children with asthma and obesity. Subsequently, we will develop and test our mCHAMP app using an iterative process that includes usability testing with target users and pediatric nurses. RESULTS: This study was funded in 2018; 13 parents of children with asthma and obesity participated in the needs assessment. Preliminary themes from focus groups and individual meetings included barriers to engaging in health-promoting behaviors, perceived relationships between asthma and obesity, facilitators to behavior change, and intervention preferences. Participatory design sessions and usability testing are expected to conclude in late 2019. CONCLUSIONS: Outcomes from this study are expected to include an mHealth app designed with direct participation from the target audience and usability data from stakeholders as well as potential end users. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/13549.

Association between pulmonary function and left ventricular volume and function in duchenne muscular dystrophy.

INTRODUCTION: Duchenne muscular dystrophy (DMD) is characterized by absence of the subsarcolemmal protein dystrophin, present in skeletal muscles and cardiomyocytes. We hypothesized that progressive respiratory and left ventricular (LV) insufficiencies in DMD could be parallel and interrelated phenomena. METHODS: We conducted a retrospective chart review of 27 patients with DMD. Our primary objective was to compare the rates of decline between pulmonary function test (PFT) measures (forced expiratory volume in the first second, forced vital capacity, peak expiratory flow rate, maximal inspiratory/expiratory pressure) and echocardiographic estimates of LV end-diastolic volume and LV ejection fraction. RESULTS: The rates of decline/year of PFTs and LV estimates were not significantly different. Pulmonary function test measures of ventilatory efficiency and strength had strong intercorrelations. Pulmonary function tests and LV estimates had weak but statistically significant correlations. DISCUSSION: A comparable rate of decline in PFTs and LV indices in DMD provides evidence for concurrently progressive deterioration in respiratory and LV functions. Muscle Nerve, 2019.

Exercise-Induced Dyspnea in Children and Adolescents: Differential Diagnosis.

Exercise-induced dyspnea in children and adolescents can occur for many reasons. Although asthma is the common cause, failure to prevent exercise-induced asthma by pretreatment with a bronchodilator, such as albuterol, indicates that other etiologies should be considered. Other causes of exercise-induced dyspnea include exercise-induced vocal cord dysfunction, exercise-induced laryngomalacia, exercise-induced hyperventilation, chest wall restrictive abnormalities, cardiac causes, and normal physiologic limitation. When exercise-induced dyspnea is not from asthma, cardiopulmonary exercise testing with reproduction of the patient's dyspnea is the means to identify the other causes. Cardiopulmonary exercise testing monitors oxygen use, carbon-dioxide production, end-tidal pCO2 (partial pressure of carbon dioxide), and electrocardiogram. Additional components to testing are measurement of blood pH and pCO2 when symptoms are reproduced, and selective flexible laryngoscopy when upper airway obstruction is observed to specifically identify vocal cord dysfunction or laryngomalacia. This approach is a highly effective means to identify exercise-induced dyspnea that is not caused by asthma. [Pediatr Ann. 2019;48(3):e121-e127.].

The association of nocturnal hypoxia and an echocardiographic measure of pulmonary hypertension in children with sickle cell disease.

BACKGROUND: Pulmonary hypertension (PH) is multifactorial in origin and may develop early in children with sickle cell disease (C-SCD). Potential etiologies are hemolysis-induced endothelial dysfunction, left ventricular (LV) dysfunction, and chronic hypoxia. Nocturnal hypoxia (NH) in C-SCD is known to be a sequela of obstructive sleep apnea (OSA). The primary objective of this study is to correlate polysomnographic evidence NH with echocardiographic measures of PH in C-SCD. METHODS: We performed a retrospective chart review of 20 C-SCD (Hemoglobin SS), who had polysomnography and echocardiogram performed within a narrow time interval, and 31% of them had pre-existing cardiac conditions. Tricuspid regurgitant jet velocity (TRJV) ≥ 2.5 m/s was considered as an indicator of PH. RESULTS: Twenty-five percent of the subjects had NH. Forty percent of C-SCD, predominantly male, had evidence of PH based on an elevated TRJV. Children with NH compared to non-NH had significantly worse baseline hypoxemia (p < 0.001), higher TRJV (p = 0.005), and higher LV end-diastolic diameters (p = 0.009). The severity of NH was influenced by OSA. However, PH was not associated with OSA or duration of hydroxyurea therapy. CONCLUSION: Our study indicates that NH is associated with PH in C-SCD, and that screening for NH may help to identify C-SCD with higher morbidity risk.

The Association Between Female Smoking and Childhood Asthma Prevalence-A Study Based on Aggregative Data.

Aims: Socioeconomic and environmental factors influence childhood asthma prevalence across the world. In-depth epidemiological research is necessary to determine the association between asthma prevalence and socio-environmental conditions, and to develop public health strategies to protect the asthmatic children against the environmental precipitators. Our research was based on aggregative data and sought to compare the asthma prevalence between children of two different age-groups across the world and to identify the association among the key socio-environmental conditions with increased childhood asthma prevalence. Method: We included forty countries with available data on various socio-environmental conditions (2014-2015). Childhood asthma prevalence of two different age groups (6-7 and 13-14 years) were obtained from global asthma report 2014. Because of significant diversities, the selected countries were divided into two groups based on human developmental index (HDI), a well-recognized parameter to estimate the overall socioeconomic status of a country. Robust linear regression was conducted using childhood asthma prevalence as the dependent variable and female smoking prevalence, tertiary school enrollment (TSE), PM10 (particulate matter ≤10 µm in diameter) and gross domestic product (GDP) as predictors. Results: Asthma prevalence was not different between two age groups. Among all predictors, only female smoking prevalence (reflecting maternal smoking) was associated with asthma prevalence in the countries with lower socio-economic conditions (HDI), but not in the higher HDI group. The results were unchanged even after randomization. Conclusions: Childhood asthma prevalence did not change significantly with age. Female smoking may have a positive correlation with childhood asthma prevalence in lower HDI countries.