Hyperventilation syndrome in children with asthma.

BACKGROUND: Hyperventilation syndrome (HVS) may be associated with asthma. In the absence of a gold standard diagnosis for children, its impact on asthma has been rarely assessed. OBJECTIVE: To assess the impact of HVS on the symptoms and lung function of children with asthma and determine the diagnostic value of the Nijmegen questionnaire in comparison to a hyperventilation test (HVT). METHODS: Data from asthmatic children followed in the department of Pediatric Pulmonology of Necker Hospital and explored for HVS were retrospectively analyzed. HVS was diagnosed by a positive HVT. Asthma exacerbations, control and lung function were assessed in children with or without a positive HVT. The sensitivity and specificity of the Nijmegen questionnaire were determined relative to the positivity of a HVT. The Nijmegen questionnaire threshold was ≥23. RESULTS: Data from 112 asthmatic children, median age 13.9 years [11.6-16], were analyzed. Twenty-eight children (25%) had mild or moderate asthma and 84 (75%) severe asthma. The HVT was performed on 108 children and was negative for 34 (31.5%) and positive for 74 (68.5%). The number of asthma exacerbations in the past 12 months, Asthma Control Test (ACT) score, and lung function did not differ between children with a positive HVT and a negative HVT. The Nijmegen questionnaire was administered to 103 children. Its sensitivity was 56.3% and specificity 56.3%. CONCLUSION: The symptoms and lung function of adolescents with asthma are not affected by the presence of HVS. The sensitivity and specificity of the Nijmegen questionnaire are low.

Geleophysic and acromicric dysplasias: natural history, genotype-phenotype correlations, and management guidelines from 38 cases.

PURPOSE: Geleophysic dysplasia (GD) and acromicric dysplasia (AD) are characterized by short stature, short extremities, and progressive joint limitation. In GD, cardiorespiratory involvement can result in poor prognosis. Dominant variants in the FBN1 and LTBP3 genes are responsible for AD or GD, whereas recessive variants in the ADAMTSL2 gene are responsible for GD only. The aim of this study was to define the natural history of these disorders and to establish genotype-phenotype correlations. METHODS: This monocentric retrospective study was conducted between January 2008 and December 2018 in a pediatric tertiary care center and included patients with AD or GD with identified variants (FBN1, LTBP3, or ADAMTSL2). RESULTS: Twenty-two patients with GD (12 ADAMTSL2, 8 FBN1, 2 LTBP3) and 16 patients with AD (15 FBN1, 1 LTBP3) were included. Early death occurred in eight GD and one AD. Among GD patients, 68% presented with heart valve disease and 25% developed upper airway obstruction. No AD patient developed life-threatening cardiorespiratory issues. A greater proportion of patients with either a FBN1 cysteine variant or ADAMTSL2 variants had a poor outcome. CONCLUSION: GD and AD are progressive multisystemic disorders with life-threatening complications associated with specific genotype. A careful multidisciplinary follow-up is needed.

The economic burden of severe asthma in children: a comprehensive study.

OBJECTIVE: The economic burden of severe asthma (SA) in children is poorly described. We aimed to determine the healthcare costs of SA in children for the French national health insurance (NHI). METHODS: Children (6-18 years of age) with physician-confirmed diagnoses of SA or non-SA (NSA) were identified. Direct and indirect expenditures related to asthma and associated co-morbidities in the previous six months were determined, based on a physician-guided parental questionnaire and confirmed by medical records. The costs for the French NHI were assessed per child over a six month period. RESULTS: Data from 74 children, including 48 with SA (22 requiring omalizumab) and 26 with NSA, were analyzed. The global cost of SA was €3,982 per child over a six-month period, including €3,821 direct costs and €161.9 indirect costs. The global cost was €6,716 (4,220) for those requiring omalizumab vs. €1,669 (3,108) for those who did not (p < 0.01). For children with SA, 65% of direct costs were attributed to medication. Among those on omalizumab, such treatment accounted for 93% of medication costs. The global cost was 10 times higher for children with SA than those with NSA (€3,982 (4,422) vs. €363.2 (352.6), p < 0.01), and 20 times higher for children with SA on omalizumab than those with NSA (p < 0.01). CONCLUSION: The economic burden of SA in children for the French NHI is substantial and mainly driven by the most severe children requiring biologics.

Nonsteroidal Anti-Inflammatory Drug without Antibiotics for Acute Viral Infection Increases the Empyema Risk in Children: A Matched Case-Control Study.

OBJECTIVE: To investigate the risk factors of empyema after acute viral infection and to clarify the hypothesized association(s) between empyema and some viruses and/or the use of nonsteroidal anti-inflammatory drugs (NSAIDs). STUDY DESIGN: A case-control study was conducted in 15 centers. Cases and controls were enrolled for a source population of children 3-15 years of age with acute viral infections between 2006 and 2009. RESULTS: Among 215 empyemas, 83 cases (children with empyema and acute viral infection within the 15 preceding days) were included, and 83 controls (children with acute viral infection) were matched to cases. Considering the intake of any drug within 72 hours after acute viral infection onset and at least 6 consecutive days of antibiotic use and at least 1 day of NSAIDs exposure, the multivariable analysis retained an increased risk of empyema associated with NSAIDs exposure (aOR 2.79, 95% CI 1.4-5.58, P = .004), and a decreased risk associated with antibiotic use (aOR 0.32, 95% CI 0.11-0.97, P = .04). The risk of empyema associated with NSAIDs exposure was greater for children not prescribed an antibiotic and antibiotic intake diminished that risk for children given NSAIDs. CONCLUSIONS: NSAIDs use during acute viral infection is associated with an increased risk of empyema in children, and antibiotics are associated with a decreased risk. The presence of antibiotic-NSAIDs interaction with this risk is suggested. These findings suggest that NSAIDs should not be recommended as a first-line antipyretic treatment during acute viral infections in children.

Beta-lactam hypersensitivity in children with cystic fibrosis: a study in a specialized pediatric center for cystic fibrosis and drug allergy.

BACKGROUND: Beta-lactam hypersensitivity (HS) is suspected in 5-12% of the children, but proven in only 10-15% of those children, based on skin and challenge tests results. In contrast, 30-60% of patients with cystic fibrosis (CF) are diagnosed allergic to beta-lactams, based mainly on the clinical history of the patients. OBJECTIVES: To confirm or rule out a suspected beta-lactam HS in CF children and to determine the prevalences of suspected and confirmed beta-lactam HS in those children. PATIENTS AND METHODS: Children with CF and suspected beta-lactam HS were explored by means of skin and challenge tests with the suspected and alternate beta-lactams. The results in CF children were compared with those reported in the literature in non- CF children. RESULTS: Eight of the 701 CF children followed in our center between 1990 and 2011 (1.14%), and 11 other children from other centers were explored for suspected beta-lactam HS. Beta-lactam HS was diagnosed in nine of these children (47.3%). Based on the results in the children followed in our center, the prevalence of beta-lactam HS was 0.71% (5/701) in CF children vs. a mean estimated prevalence of 1-1.5% in the general pediatric population. CONCLUSION: Our results contrast with those of most previous studies. Although half of the CF children with suspected beta-lactam HS were truly allergic to beta-lactams, the general prevalence of beta-lactam HS in CF children was very low. This may result from tolerance induced by frequent and/or prolonged treatments with beta-lactams.

Asphyxiating thoracic dysplasia: clinical and molecular review of 39 families.

BACKGROUND: Asphyxiating Thoracic Dysplasia (ATD) belongs to the short rib polydactyly group and is characterized by a narrow thorax, short long bones and trident acetabular roof. Other reported features include polydactyly, renal, liver and retinal involvement. To date, mutations in IFT80, DYNC2H1, TTC21B and WDR19 have been reported in ATD. The clinical and molecular heterogeneity leads to difficulties in the evaluation of the long-term prognosis. METHODS: We investigated 53 ATD cases (23 living cases and 30 fetuses) from 39 families. They benefited from a combined approach of deep phenotyping and IFT80 and DYNC2H1 molecular screening. RESULTS: Among the 23 postnatal cases, pulmonary insufficiency was noted in 60% of cases, with tracheotomy requirement in five cases. Renal and liver diseases occurred respectively in 17% and 22% of cases, whereas retinal alteration was present in 50% of cases aged more than 5 years. We identified DYNC2H1 mutations in 23 families (59%) and IFT80 mutations in two families (5%). However, in six families, only one heterozygote mutation in either IFT80 or DYNC2H1 was identified. Finally, the two genes were excluded in 14 families (36%). CONCLUSIONS: We conclude that DYNC2H1 is a major gene responsible for ATD, while IFT80 is rarely involved. The presence of only one mutation in six families and the exclusion of the two genes in 14 families support the involvement of other causal cilia genes. The long-term follow up emphasizes that the pulmonary prognosis is probably less pejorative and retinal involvement more frequent than previously thought.

Primary pulmonary alveolar proteinosis: computed tomography features at diagnosis.

BACKGROUND: Pulmonary alveolar proteinosis (PAP) is characterized by an abnormal accumulation of periodic acid-schiff-positive lipoproteinaceous material in the alveoli. Early diagnosis allows setting up of therapeutic lung lavages, which reduces the need for oxygen supplementation and weight gain. OBJECTIVE: To provide a description of radiological features by CT at the onset of primary PAP in children. MATERIALS AND METHODS: The clinical and radiological data of 24 patients, including 16 boys and 8 girls (median age: 12 months), diagnosed with a primary form of PAP between April 1992 and May 2012 in a tertiary referral hospital, were retrospectively reviewed. CT images were examined for the presence of alveolar and interstitial elementary lesions. Correlation between clinical and radiological findings was assessed. RESULTS: The types of elementary lesions detected were: ground-glass opacities (n = 24), intralobular lines (n = 24), thickened interlobular septa (n = 22), thickened fissures (n = 21), airspace consolidation (n = 16), hyperinflation (n = 16), cystic lesions (n = 2) and micronodules (n = 1). A crazy-paving pattern was found in 92% of cases. Consolidation and hyperinflation were especially detected in younger children (median age, 8 months, P < 0.01). A density dependent gradient was found. The distribution of the lesions was symmetrical. There was no correlation between radiological and clinical data of severity of the disease. CONCLUSION: CT findings are suggestive of diagnosis of PAP in immunocompetent children with chronic respiratory failure.

Late-onset pulmonary complications following allogeneic hematopoietic cell transplantation in pediatric patients: a prospective multicenter study.

The primary objective of our multicenter prospective study was to describe the incidence of late-onset non-infectious pulmonary complications (LONIPCs) in children undergoing hematopoietic cell transplantation (HCT) using sensitive criteria for pulmonary function test (PFT) abnormalities including the non-specific pattern of airflow obstruction. Secondary objectives were to assess the factors associated with LONIPC occurrence and the sensitivity of the 2014 NIH-Consensus Criteria of bronchiolitis obliterans syndrome (BOS). PFT and clinical assessment were performed prior to HCT and at 6, 12, 24, and 36 months post-HCT. LONIPC diagnosis was validated by an Adjudication Committee. The study comprised 292 children from 12 centers. Thirty-two individuals (11%, 95% CI: 8-15%) experienced 35 LONIPCs: 25 BOS, 4 interstitial lung diseases, 4 organizing pneumonia and 2 pulmonary veno-occlusive diseases. PFT abnormalities were obstructive defects (FEV1/FVC z-score < -1.645; n = 12), restrictive defects (TLC < 80% predicted, FEV1 and FVC z-scores < -1.645; n = 7) and non-specific pattern (FEV1 and FVC z-score< -1.645, FEV1/FVC z-score > -1.645, and TLC > 80% predicted; n = 8). HCT for malignant disease was the only factor associated with LONIPC (P = 0.04). The 2014 NIH-Consensus Criteria would only diagnose 8/25 participants (32%) as having BOS. In conclusion, 11% of children experienced a LONIPC in a prospective design. Clinical Trials.gov identifier (NCT number): NCT02032381.

Inhaled therapies, azithromycin and Mycobacterium abscessus in cystic fibrosis patients.

Cystic fibrosis (CF) patients are at particularly high risk of developing lung disease caused by Mycobacterium abscessus complex (MABSC). Over the last 10 years, changes in CF treatment, with increasing use of inhaled therapies and low-dose azithromycin, have been accompanied by an increase in the prevalence of MABSC infections in CF patients. There is therefore some concern about the role of new CF treatments in the emergence of MABSC infections. We addressed this issue by means of a case-control study including 30 MABSC-positive cases and 60 nontuberculous mycobacteria-negative CF controls matched for age, sex and centre. We also compared practices at the CF centres with the highest prevalence of MABSC with those at the other centres. No positive association was found between MABSC lung disease and the use of inhaled therapies or low-dose azithromycin in the 4 years preceding MABSC isolation. These treatments were not significantly more frequently used at the CF centres with the highest MABSC prevalence rates. In conclusion, there is no evidence for a link between M. abscessus complex lung disease and inhaled therapies or low-dose azithromycin in patients with CF.

Respiratory outcome in children with scimitar syndrome.

OBJECTIVE: To evaluate respiratory morbidities and lung function tests in the cohort of patients with scimitar syndrome evaluated at our center since 1976. STUDY DESIGN: Eighty-one children were investigated. Twenty-six patients died, all with the infantile form. The median duration of follow-up of surviving children was 7.2 years. RESULTS: A high rate of respiratory morbidities was measured, with 38% and 43% of children reporting pulmonary infections or wheezing episodes during the last 12 months of follow-up, respectively. One-third of children have been rehospitalized for a respiratory cause. Lung function tests were obtained in 20 children. The median value of total lung capacity was 73.0% of the predicted value (IQR, 65.3-86.8), and the median value of the ratio of the forced expiratory volume in one second to the forced vital capacity was -1.26 Z score (-2.25; -0.31). Significantly lower total lung capacity values were obtained in children with the infantile form (P < .005) or with a history of thoracic surgery (P = .002). The ratio of the forced expiratory volume in one second to the forced vital capacity Z score values were significantly lower in boys (P < .05) and in children with a history of wheezing (P = .01). Wheezing episodes were not associated with significant salbutamol-induced reversibility. CONCLUSION: Respiratory complications frequently are observed in children with scimitar syndrome. Pulmonary hypoplasia appears as an independent marker of long-term severity in these patients.

Proteomic profiling of sweat in patients with cystic fibrosis provides new insights into epidermal homoeostasis.

Background: A high proportion of patients with Cystic Fibrosis (CF) also present the rare skin disease aquagenic palmoplantar keratoderma. A possible link between this condition and absence of a functional CF Transmembrane conductance Regulator protein in the sweat acinus and collecting duct remains unknown. Methods: In-depth characterization of sweat proteome profiles was performed in 25 CF patients compared to 12 healthy controls. A 20 µL sweat sample was collected after pilocarpine iontophoresis and liquid chromatography tandem mass spectrometry (LC-MS/MS) proteomic analysis was performed. Results: Sweat proteome profile of CF patients was significantly different from that of healthy subjects with 57 differentially expressed proteins. Cystic Fibrosis sweat proteome was characterized by an increase in 25 proteins including proteases (Kallikrein 7 and 13, Phospholipase B domain containing 1, Cathepsin A L2 and B, Lysosomal Pro-X carboxypeptidase); proinflammatory proteins (Annexin A2, Chitinase-3-like protein 1); cytochrome c and transglutaminases. Thirty-two proteins were downregulated in CF sweat including proteases (Elastase 2), antioxidative protein FAM129 B; membrane-bound transporter SLC6A14 and regulator protein Sodium-hydrogen antiporter 3 regulator 1. Conclusion: This study is the first to report in-depth characterization of endogenous peptides in CF sweat and could help understand the complex physiology of the sweat gland. The proteome profile highlights the unbalanced proteolytic and proinflammatory activity of sweat in CF. These results also suggest a defect in pathways involved in skin barrier integrity in CF patients. Sweat proteome profile could prove to be a useful tool in the context of personalized medicine in CF.

High Nasal Nitric Oxide, Cilia Analyses, and Genotypes in a Retrospective Cohort of Children with Primary Ciliary Dyskinesia.

Rationale: Although children with primary ciliary dyskinesia (PCD) typically have low nasal nitric oxide (nNO), some children with indisputable PCD may have unexplained high nNO concentrations. Objectives: To look for relationships between nNO measures and genetic findings (and cilia motility or ultrastructure when available) in children with PCD with known genotypes. Methods: We retrospectively studied 73 children with PCD (median age, 9.5 [range, 2.1-18.2] yr). nNO was the mean value of a plateau reached while the velum was closed (nNO-VC; threshold, 77 nl ⋅ min-1) or was calculated as the average of five peaks obtained during tidal breathing (threshold, 40 nl ⋅ min-1). Ciliary beat was classified as either motile (including dyskinetic pattern) or immotile, depending on whether motility was present or absent in all cilia, or as a mixture of motile and immotile cilia. Genotypes were classified as pathogenic mutations in genes known to be associated with high nNO (mild genotype), biallelic truncating mutations in other genes (severe mutations), or putative hypomorphic pathogenic mutations (missense, single amino acid deletion, or moderate splicing mutations) in at least one allele believed to be possibly associated with residual production of a functional protein. Results: nNO was above the discriminant threshold in 16 of 73 (21.9%) children (11 nNO-VC and 5 nNO during tidal breathing). High nNO was less frequent in children with severe mutations (2 of 42) than in those with mild genotypes (7 of 10) or at least one hypomorphic mutation (7 of 21) (P < 0.0001). Median (interquartile range) nNO-VC values (n = 60) were significantly different in the three genotype groups: severe mutations, 18 (10-26) nl ⋅ min-1 (n = 36); possible residual functional protein production (putative hypomorphic mutations), 23 (16-68) nl ⋅ min-1 (n = 17); and mild genotypes, 139 (57-216) nl ⋅ min-1 (n = 7) (P = 0.0002). The higher the cilia motility, the higher the nNO-VC (16 [10-23], 23 [17-56], and 78 [45-93] nl ⋅ min-1 in patients with immotile, dyskinetic motile and immotile, and dyskinetic motile cilia, respectively; P < 0.0001), while nNO values were scattered across different ultrastructure defects (P = 0.07). Conclusions: In children with PCD, high nNO values were linked not only to specific genes but also to potentially hypomorphic mutations in other genes (with possible functional protein production). nNO values increased with the proportion of motile cilia.

Lumacaftor-ivacaftor effects on cystic fibrosis-related liver involvement in adolescents with homozygous F508 del-CFTR.

BACKGROUND: The effects of lumacaftor-ivacaftor on cystic fibrosis transmembrane conductance regulator (CFTR)-associated liver disease remain unclear. The objective of the study was to describe the effect of this treatment on features of liver involvement in a cystic fibrosis (CF) adolescent population homozygous for F508del. METHODS: Clinical characteristics, liver blood tests, abdominal ultrasonography (US), and pancreas and liver proton density fat fraction (PDFF) by magnetic resonance imaging, were obtained at treatment initiation and at 12 months for all patients. Biomarkers of CFTR activity (sweat chloride test, nasal potential difference, and intestinal current measurement) were assessed at initiation and at 6 months therapy. RESULTS: Of the 37 patients who started ivacaftor/lumacaftor treatment, 28 were eligible for analysis. In this group, before treatment initiation, 4 patients were diagnosed with multinodular liver and portal hypertension, 19 with other forms of CF liver involvement, and 5 with no signs of liver involvement. During treatment, no hepatic adverse reactions were documented, and no patient developed liver failure. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gammaglutamyl transferase (GGT) decreased significantly following initiation of lumacaftor-ivacaftor, and remained so after 12 months treatment. This was not correlated with changes in clinical status, liver and pancreas US and PDFF, fecal elastase, or lumacaftor-ivacaftor serum levels. The most "responsive" patients demonstrated a significant increase in biomarkers of CFTR activity. CONCLUSIONS: These results may suggest a potential beneficial effect of CFTR modulators on CF liver disease and warrant further investigation in larger, prospective studies.

Real-world assessment of LCI following lumacaftor-ivacaftor initiation in adolescents and adults with cystic fibrosis.

Lung clearance index (LCI) is a biomarker of ventilation inhomogeneity. Data are scarce on its usefulness in daily practice for monitoring the effects of treatments in older children and adults with CF. In this French observational study of lumacaftor-ivacaftor, 63 of 845 patients (7.5%) had available LCI performed at baseline and at six (M6; n=34) or 12 months (M12; n=46) after lumacaftor-ivacaftor initiation. At inclusion, median [IQR] age was 16 years [13-17], ppFEV1 was 72.8 [59.6-80.7], and LCI was 12.3 [10.3-15.0]. At both M6 and M12, no statistically significant LCI increases of 0.13 units or 1.34% (95% CI: -4.85-7.53) and 0.6 units or 6.66% (95% CI: -0.03-13.5) were observed. Discordant results between LCI and ppFEV1 were observed in one-third of the patients. In daily practice, LCI monitoring in adolescents and young adults with moderate lung disease gives results that are more heterogenous than those reported in children with milder disease.

Chest physiotherapy enhances detection of Pseudomonas aeruginosa in nonexpectorating children with cystic fibrosis.

Lung damage in cystic fibrosis (CF) is strongly associated with lower airway infections. Early treatment of Pseudomonas aeruginosa is recommended. Pathogen detection requires sampling of lower airway secretions, which remains a challenge in nonexpectorating patients. Our hypothesis was that chest physiotherapy would improve the quality of airway secretion samples and increase the rates of pathogens detected in nonexpectorating patients. This prospective multicentre study compared three successive methods for sampling airway secretions applied through the same session: 1) an oropharyngeal swab (OP), 2) a chest physiotherapy session followed by a provoked cough to obtain sputum (CP-SP) and 3) a second oropharyngeal swab collected after chest physiotherapy (CP-OP). Haemophilus influenzae, Staphylococcus aureus and P. aeruginosa growth cultures were assessed. Accuracy tests and an equivalence test were performed to compare the three successive methods of collection. 300 nonexpectorating children with CF were included. P. aeruginosa was detected cumulatively in 56 (18.9%) children, and according to the different collection methods in 28 (9.8%), 37 (12.4%) and 44 (14.7%) children by using OP, CP-OP and CP-SP, respectively. Compared with OP, the increased detection rate was +22% for CP-OP (p=0.029) and +57% for CP-SP (p=0.003). CP-SP had the best positive predictive value (86.3%) and negative predictive value (96.0%) for P. aeruginosa compared with the overall detection. The results of this adequately powered study show differences in the rates of pathogens detected according to the sampling method used. Chest physiotherapy enhanced detection of P. aeruginosa in nonexpectorating children with CF.