Pre and post-COVID 19 infection pulmonary functions in children with chronic respiratory disease: A case series.

As functional respiratory impairment following COVID-19 infection (COVID-19) is increasingly reported in adult, data regarding children especially with pre-existing chronic respiratory disease (PCRD) remain scarce. We retrospectively assessed clinical presentation, duration of symptoms related to COVID-19 from paediatric patients with PCRD and compared their pre/post COVID-19-I spirometry values. Data from 12 patients were analysed. Timing between COVID-19 diagnosis and subsequent functional evaluation ranged from 26 to 209 days (mean 77). The PCRD in these patients included asthma, cystic fibrosis, bronchiolitis obliterans and bronchomalacia. During COVID-19, all clinical presentations were mild. One patient displayed persistent post-COVID-19 symptoms for 8 weeks after infection. Two patients presented significant deterioration of post-COVID-19 spirometric values with a return to pre-COVID-19 values in subsequent measures. We concluded that children with PCRD are not at increased risk for severe COVID disease and that most of them have no or only transient pulmonary functional impairment 1 to 7 months after COVID-19.

Routine lung volume recruitment in boys with Duchenne muscular dystrophy: a randomised clinical trial.

BACKGROUND: Impaired cough results in airway secretion retention, atelectasis and pneumonia in individuals with Duchenne muscular dystrophy (DMD). Lung volume recruitment (LVR) stacks breaths to inflate the lungs to greater volumes than spontaneous effort. LVR is recommended in DMD clinical care guidelines but is not well studied. We aimed to determine whether twice-daily LVR, compared with standard of care alone, attenuates the decline in FVC at 2 years in boys with DMD. METHODS: In this multicentre, assessor-blinded, randomised controlled trial, boys with DMD, aged 6-16 years with FVC >30% predicted, were randomised to receive conventional treatment or conventional treatment plus manual LVR twice daily for 2 years. The primary outcome was FVC % predicted at 2 years, adjusted for baseline FVC % predicted, age and ambulatory status. Secondary outcomes included change in chest wall distensibility (maximal insufflation capacity minus FVC) and peak cough flow. RESULTS: Sixty-six boys (36 in LVR group, 30 in control) were evaluated (median age (IQR): 11.5 years (9.5-13.5), median baseline FVC (IQR): 85% predicted (73-96)). Adjusted mean difference in FVC between groups at 2 years was 1.9% predicted (95% CI -6.9% to 10.7%; p=0.68) in the direction of treatment benefit. We found no differences in secondary outcomes. CONCLUSION: There was no difference in decline in FVC % predicted with use of twice-daily LVR for boys with DMD and relatively normal lung function. The burden associated with routine LVR may outweigh the benefit. Benefits of LVR to maintain lung health in boys with worse baseline lung function still need to be clarified. TRIAL REGISTRATION NUMBER: NCT01999075.

Inhaled Antibiotics for the Prevention of Respiratory Tract Infections in Children With a Tracheostomy.

Objective: To describe the use of prophylactic inhaled antibiotics in children with a tracheostomy and assess if its use is associated with a reduction in exposition to broad-spectrum antibiotics and a lower risk of acquired respiratory tract infections. Methods: A case series study was performed in a tertiary care university affiliated hospital. All consecutive children (<18 years old) with a tracheostomy, hospitalized between January 2004 and November 2016, and treated with prophylactic inhaled antibiotics were identified. We analyzed the 3 month- period before and after initiation of prophylactic inhaled antibiotics and described exposure to broad spectrum antibiotics, the number of respiratory tract infections and the associated adverse events. Results: Six children (median age: 11 months, range: 8-100) were included. One received colimycin, 3 received tobramycin and 2 were treated with both antibiotics in alternance. The median duration of treatment was 74 days (22-173) with one patient still being treated at the end of the study. Patients were exposed to systemic antibiotics for 18 days (2-49) in the 3 months preceding the treatment vs. 2 days (0-15) in the 3 months following the treatment initiation (p = 0.115). The number of respiratory tract infections went from median of 2 (0-3) to 1 (0-1) during the same periods (p = 0.07). Adverse events most commonly reported were cough (n = 2) and increased respiratory secretions post-inhalation (n = 4). Only one new bacterial resistance was observed. Conclusions: This series of consecutive cases underlines the need for future studies evaluating the potential benefit of prophylactic inhaled antibiotics in children with a tracheostomy.

Minimal change in structural, functional and inflammatory markers of lung disease in newborn screened infants with cystic fibrosis at one year.

BACKGROUND: With the widespread introduction of newborn screening for cystic fibrosis (CF), there has been considerable emphasis on the need to develop objective markers of lung health that can be used during infancy. We hypothesised that in a newborn screened (NBS) UK cohort, evidence of airway inflammation and infection at one year would be associated with adverse structural and functional outcomes at the same age. METHODS: Infants underwent lung function testing, chest CT scan and bronchoscopy with bronchoalveolar lavage (BAL) at 1 year of age when clinically well. Microbiology cultures were also available from routine cough swabs. RESULTS: 65 infants had lung function, CT and BAL. Mean (SD) lung clearance index and forced expiratory volume in 0.5 s z-scores were 0.9(1.2) and -0.6(1.1) respectively; median Brody II CF-CT air trapping score on chest CT =0 (interquartile range 0-1, maximum possible score 27). Infants isolating any significant pathogen by 1 yr of age had higher LCI z-score (mean difference 0.9; 95%CI:0.4-1.4; p = 0.001) and a trend towards higher air trapping scores on CT (p = 0.06). BAL neutrophil elastase was detectable in 23% (10/43) infants in whom BAL supernatant was available. This did not relate to air trapping score on CT. CONCLUSIONS: In this UK NBS cohort at one year of age, lung and airway damage is much milder and associations between inflammation, abnormal physiology and structural changes were at best weak, contrary to our hypothesis and previously published reports. Continued follow-up will clarify longer term implications of these very mild structural, functional and inflammatory changes.

Home high-flow nasal cannula as a treatment for severe tracheomalacia: A pediatric case report.

Tracheomalacia refers to a softness of the tracheal cartilage that makes the airway more susceptible to collapse. In contrast to milder cases where conservative therapy is preferred, severe tracheomalacia is often a life threatening condition requiring more aggressive management. For children with this condition, a variety of treatment options are available. To our knowledge, this is the first report of home high-flow nasal cannula as an alternative therapy to continuous positive airway pressure (CPAP) and surgical procedures in a pediatric patient with severe extensive tracheomalacia.

Evolution of lung function during the first year of life in newborn screened cystic fibrosis infants.

RATIONALE: Newborn screening (NBS) for cystic fibrosis (CF) allows early intervention. Design of randomised controlled trials (RCT) is currently impeded by uncertainty regarding evolution of lung function, an important trial end point in such infants. OBJECTIVE: To assess changes in pulmonary function during the first year of life in CF NBS infants. METHODS: Observational longitudinal study. CF NBS infants and healthy controls were recruited between 2009 and 2011. Lung Clearance Index (LCI), plethysmographic lung volume (plethysmographic functional residual capacity (FRCpleth)) and forced expired volume (FEV0.5) were measured at 3 months and 1 year of age. MAIN RESULTS: Paired measurements were obtained from 72 CF infants and 44 controls. At 3 months, CF infants had significantly worse lung function for all tests. FEV0.5 improved significantly (0.59 (95% CI 0.18 to 0.99) z-scores; p<0.01) in CF infants between 3 months and 1 year, and by 1 year, FEV0.5 was only 0.52 (0.89 to 0.15) z-scores less than in controls. LCI and FRCpleth remained stable throughout the first year of life, being on average 0.8 z-scores higher in infants with CF. Pulmonary function at 1 year was predicted by that at 3 months. Among the 45 CF infants with entirely normal LCI and FEV0.5 at 3 months, 80% remained so at 1 year, while 74% of those with early abnormalities remained abnormal at 1 year. CONCLUSIONS: This is the first study reporting improvements in FEV0.5 over time in stable NBS CF infants treated with standard therapy. Milder changes in lung function occurred by 1 year than previously reported. Lung function at 3 months predicts a high-risk group, who should be considered for intensification of treatment and enrolment into RCTs.

New reference equations to improve interpretation of infant lung function.

RATIONALE: With increasing use of infant pulmonary function tests (IPFTs) in both clinical and research studies, appropriate interpretation of results is essential. OBJECTIVES: To investigate the potential bias associated with "normalising" IPF by expressing results as a ratio of body size and to develop reference ranges for tidal breathing parameters, passive respiratory mechanics (compliance [Crs] and resistance [Rrs]) and plethysmographic functional residual capacity (FRCp ) for white infants during the first 2 years of life. METHODS: IPFTs were measured using the Jaeger BabyBody system and standardized protocols. Reference equations, adjusted for body size, age, and sex where appropriate, were created using multilevel modeling. RESULTS: The ratio of lung function to body length changes markedly with growth, thereby precluding its use for any outcome. While the ratio of tidal volume and Crs to body weight remained relatively constant with growth, this was not the case for FRCp . Even in healthy infants, a strong inverse relationship was observed between lung function/body weight and weight z-score which could distort interpretation of results in growth-restricted infants with lung disease, such as cystic fibrosis. Reference equations were derived from 153 healthy white infants on 232 test occasions (median age 35.5 weeks [range: 2.6-104.7]). Crown-heel length was the strongest predictor of IPF. CONCLUSIONS: When reporting IPF, use of size-corrected ratios should be discouraged, with interpretation instead based on appropriate reference equations. The current equations are applicable to white infants and young children up to 2 years of age, studied using the same commercially available equipment. The extent to which these equations are applicable to infants and young children of other ethnic backgrounds or who are tested with different equipment needs to be established.

Positive parental attitudes to participating in research involving newborn screened infants with CF.

BACKGROUND: Information regarding recruitment of infants to research studies following the diagnosis of cystic fibrosis (CF) via newborn screening (NBS) is not currently available. This study aimed to assess parental attitudes and the feasibility of recruiting and retaining both NBS infants with CF and healthy control infants to a longitudinal, observational study. METHODS: All infants underwent pulmonary function tests (PFTs) at ~3 and ~12months of age. Infants with CF had additional combined chest high resolution computed tomography (HRCT), bronchoscopy and broncho-alveolar lavage (BAL) at ~12months of age. Parental attitude questionnaires (PAQs) were administered to all parents following the ~3month PFTs and to parents of infants with CF after completion of all tests at ~12months. RESULTS: 86% (92/107) of families whose infant had CF consented to participate, of whom 92% had PFTs at ~3months of age with 99% of these having PFTs at ~12months of age. Recruitment of healthy controls was feasible but more challenging; 29% of those contacted agreed to participate; 73% of these had PFTs at ~3months of age; of whom 83% had repeated PFTs at ~12months of age. Completed PAQs were received from 71% of parents, (both of CF and healthy infants) at ~3months and from 58% parents of infants with CF at ~12months. Responses from the PAQs were generally positive, 95% of parents indicated they would recommend participation in such studies to other families. Discrepancies between responses at 3 and 12months suggested that parental understanding of what the research entailed developed during the course of the study. CONCLUSIONS: The high recruitment and retention rates for newly diagnosed CF NBS infants to this observational study are encouraging. These findings will help inform future study design both in the field of CF and other conditions diagnosed by NBS.

Lung function is abnormal in 3-month-old infants with cystic fibrosis diagnosed by newborn screening.

BACKGROUND: Long-term benefits of newborn screening (NBS) for cystic fibrosis (CF) have been established with respect to nutritional status, but effects on pulmonary health remain unclear. HYPOTHESIS: With early diagnosis and commencement of standardised treatment, lung function at ∼3 months of age is normal in NBS infants with CF. METHODS: Lung clearance index (LCI) and functional residual capacity (FRC) using multiple breath washout (MBW), plethysmographic (pleth) FRC and forced expirations from raised lung volumes were measured in 71 infants with CF (participants in the London CF Collaboration) and 54 contemporaneous healthy controls age ∼3 months. RESULTS: Compared with controls, and after adjustment for body size and age, LCI, FRC(MBW) and FRC(pleth) were significantly higher in infants with CF (mean difference (95% CI): 0.5 (0.1 to 0.9), p=0.02; 0.4 (0.1 to 0.7), p=0.02 and 0.9 (0.4 to 1.3), p<0.001, z-scores, respectively), while forced expiratory volume (FEV(0.5)) and flows (FEF(25-75)) were significantly lower (-0.9 (-1.3 to -0.6), p<0.001 and -0.7 (-1.1 to -0.2), p=0.004, z-scores, respectively). 21% (15/70) of infants with CF had an elevated LCI (>1.96 z-scores) and 25% (17/68) an abnormally low FEV(0.5) (below -1.96 z-scores). While only eight infants with CF had abnormalities of LCI and FEV(0.5), using both techniques identified abnormalities in 35% (24/68). Hyperinflation (FRC(pleth) >1.96 z-scores) was identified in 18% (10/56) of infants with CF and was significantly correlated with diminished FEF(25-75) (r=-0.43, p<0.001) but not with LCI or FEV(0.5). CONCLUSION: Despite early diagnosis of CF by NBS and protocol-driven treatment in specialist centres, abnormal lung function, with increased ventilation inhomogeneity and hyperinflation and diminished airway function, is evident in many infants with CF diagnosed through NBS by 3 months of age.