Epidemiology of childhood interstitial lung disease in France: the RespiRare cohort.

INTRODUCTION: Interstitial lung disease in children (chILD) are rare and mostly severe lung diseases. Very few epidemiological data are available in limited series of patients. The aim of this study was to assess the prevalence and incidence of chILD in France. METHODS: We performed within the RespiRare network a multicentre retrospective observational study in patients with chILD from 2000 to 2022 and a prospective evaluation of chILD's incidence between February 2022 and 2023. RESULTS: chILD was reported in 790 patients in 42 centres. The estimated 2022 prevalence in France was 44 /million children (95% CI 40.76 to 47.46) and the computed incidence was 4.4 /million children (95% CI 3.44 to 5.56). The median age at diagnosis was 3 months with 16.9% of familial forms. Lung biopsy and genetic analyses were performed in 23.4% and 76.9%, respectively. The most frequent chILD aetiologies in the <2 years group were surfactant metabolism disorders (16.3%) and neuroendocrine cell hyperplasia of infancy (11.8%), and in the 2-18 years group diffuse alveolar haemorrhage (12.2%), connective tissue diseases (11.4%), hypersensitivity pneumonitis (8.8%) and sarcoidosis (8.8%). The management included mainly oxygen therapy (52%), corticosteroid pulses (56%), oral corticosteroids (44%), azithromycin (27.2%), enteral nutrition (26.9%), immunosuppressants (20.3%) and hydroxychloroquine (15.9%). The 5-year survival rate was 57.3% for the patients diagnosed before 2 years and 86% between 2 and 18 years. CONCLUSION: This large and systematic epidemiological study confirms a higher incidence and prevalence of chILD than previously described. In order to develop international studies, efforts are still needed to optimise the case collection and to harmonise diagnostic and management practices.

COBRAPed cohort: Do sensitization patterns differentiate children with severe asthma from those with a milder disease?

BACKGROUND: It is unclear whether sensitization patterns differentiate children with severe recurrent wheeze (SRW)/severe asthma (SA) from those with non-severe recurrent wheeze (NSRW)/non-severe asthma (NSA). Our objective was to determine whether sensitization patterns can discriminate between children from the French COBRAPed cohort with NSRW/NSA and those with SRW/SA. METHODS: IgE to 112 components (c-sIgE) (ImmunoCAP® ISAC) were analyzed in 125 preschools (3-6 years) and 170 school-age children (7-12 years). Supervised analyses and clustering methods were applied to identify patterns of sensitization among children with positive c-sIgE. RESULTS: We observed c-sIgE sensitization in 51% of preschool and 75% of school-age children. Sensitization to house dust mite (HDM) components was more frequent among NSRW than SRW (53% vs. 24%, p < .01). Sensitization to non-specific lipid transfer protein (nsLTP) components was more frequent among SA than NSA (16% vs. 4%, p < .01) and associated with an FEV1/FVC < -1.64 z-score. Among sensitized children, seven clusters with varying patterns were identified. The two broader clusters identified in each age group were characterized by "few sensitizations, mainly to HDM." One cluster (n = 4) with "multiple sensitizations, mainly to grass pollen, HDM, PR-10, and nsLTP" was associated with SA in school-age children. CONCLUSIONS: Although children with wheeze/asthma display frequent occurrences and high levels of sensitization, sensitization patterns did not provide strong signals to discriminate children with severe disease from those with milder disease. These results suggest that the severity of wheeze/asthma may depend on both IgE- and non-IgE-mediated mechanisms.

Use of 2,6-diaminopurine as a potent suppressor of UGA premature stop codons in cystic fibrosis.

Nonsense mutations are responsible for around 10% of cases of genetic diseases, including cystic fibrosis. 2,6-diaminopurine (DAP) has recently been shown to promote efficient readthrough of UGA premature stop codons. In this study, we show that DAP can correct a nonsense mutation in the Cftr gene in vivo in a new CF mouse model, in utero, and through breastfeeding, thanks, notably, to adequate pharmacokinetic properties. DAP turns out to be very stable in plasma and is distributed throughout the body. The ability of DAP to correct various endogenous UGA nonsense mutations in the CFTR gene and to restore its function in mice, in organoids derived from murine or patient cells, and in cells from patients with cystic fibrosis reveals the potential of such readthrough-stimulating molecules in developing a therapeutic approach. The fact that correction by DAP of certain nonsense mutations reaches a clinically relevant level, as judged from previous studies, makes the use of this compound all the more attractive.

Lung Transplantation under a Janus Kinase Inhibitor in Three Patients with SAVI Syndrome.

Stimulator of interferon genes (STING)-associated vasculopathy with onset in infancy (SAVI) is a very rare autoinflammatory disease related to STING1 mutation. SAVI is mainly characterized by fever attacks and skin and respiratory manifestations such as interstitial lung disease or alveolar hemorrhage. Respiratory involvement occurs in 80% of cases and might progress to severe lung fibrosis and require lung transplantation (LT). Three patients with SAVI who underwent LT have been reported to date. Two of the three patients died months or years after LT due to multiple organ failure or sepsis. However, the diagnosis of SAVI was made after LT, thus preventing the use of targeted therapy, such as the Janus kinase 1 and 2 inhibitor (JAK1/2i) ruxolitinib, which might be beneficial for the respiratory status of these patients. We aimed to report our experience in managing three patients who were followed in three large lung transplantation centers in France and who benefited from ruxolitinib before undergoing LT. We describe posttransplant complications that occurred as well as outcomes.

Theratyping cystic fibrosis patients to guide elexacaftor/tezacaftor/ivacaftor out-of-label prescription.

BACKGROUND: Around 20% of people with cystic fibrosis (pwCF) do not have access to the triple combination elexacaftor/tezacaftor/ivacaftor (ETI) in Europe because they do not carry the F508del allele on the CF transmembrane conductance regulator (CFTR) gene. Considering that pwCF carrying rare variants may benefit from ETI, including variants already validated by the US Food and Drug Administration (FDA), a compassionate use programme was launched in France. PwCF were invited to undergo a nasal brushing to investigate whether the pharmacological rescue of CFTR activity by ETI in human nasal epithelial cell (HNEC) cultures was predictive of the clinical response. METHODS: CFTR activity correction was studied by short-circuit current in HNEC cultures at basal state (dimethyl sulfoxide (DMSO)) and after ETI incubation and expressed as percentage of normal (wild-type (WT)) CFTR activity after sequential addition of forskolin and Inh-172 (ΔI ETI/DMSO%WT). RESULTS: 11 pwCF carried variants eligible for ETI according to the FDA label and 28 carried variants not listed by the FDA. ETI significantly increased CFTR activity of FDA-approved CFTR variants (I601F, G85E, S492F, M1101K, R347P, R74W;V201M;D1270N and H1085R). We point out ETI correction of non-FDA-approved variants, including N1303K, R334W, R1066C, Q552P and terminal splicing variants (4374+1G>A and 4096-3C>G). ΔI ETI/DMSO%WT was significantly correlated to change in percentage predicted forced expiratory volume in 1 s and sweat chloride concentration (p<0.0001 for both). G85E, R74W;V201M;D1270N, Q552P and M1101K were rescued more efficiently by other CFTR modulator combinations than ETI. CONCLUSIONS: Primary nasal epithelial cells hold promise for expanding the prescription of CFTR modulators in pwCF carrying rare mutants. Additional variants should be discussed for ETI indication.

Outcome of patients with cystic fibrosis colonized by Scedosporium and Lomentospora species: A longitudinal cohort study.

Scedosporium and Lomentospora species rank second among the filamentous fungi colonizing the airways of cystic fibrosis (CF) patients. These fungi could be responsible for allergic bronchopulmonary mycosis (ABPM) and bronchitis before lung transplantation and invasive infections after. However, their role in CF lung disease is debated. This study aimed to identify clinical or environmental factors associated with an airway colonization by Scedosporium/Lomentospora species in patients with CF over a period of 7 years. A longitudinal cohort study was conducted from 2008 to 2014 in the CF reference centre in Lyon, France, to compare the characteristics of patients with Scedosporium/Lomentospora colonized and non-colonized patients. During the study period, 283 patients completed the clinical and microbiological follow-up. The analysis revealed that a higher number and duration of hospitalizations, an increased number of courses of parenteral antibiotic therapy, a history of ABPA, and treatment by itraconazole were significantly associated with an airway colonization by Scedosporium/Lomentospora species. The rate of decline of forced expiratory volume in the first second was not statistically different between colonized and non-colonized patients. This study provides evidence that patients colonized by Scedosporium/Lomentospora species require more medical care than non-colonized patients. Additional care could be in part explained by the management of Scedosporium/Lomentospora-related diseases such as ABPM or bronchitis. However, we did not demonstrate a faster rate of decline of respiratory function or body mass index in colonized patients, suggesting, as previously reported, that colonization of the airways by these fungi does not play a significant role in the progression of CF disease.

This prospective study did not demonstrate a faster rate of decline of respiratory function or body mass index in cystic fibrosis (CF) patients colonized by Scedosporium/Lomentospora species compared to non-colonized patients, suggesting that these fungi do not play a significant role in the progression of CF disease.

Long-term evolution of neuroendocrine cell hyperplasia of infancy: the FRENCHI findings.

Only few studies report long-term evolution of patients with neuroendocrine cell hyperplasia of infancy (NEHI). We report data from a 54-patient cohort followed up in the French network for rare respiratory diseases (RespiRare). Demographic characteristics and respiratory and nutritional evolution were collected at the time of the patient's last scheduled visit. The mean duration of follow-up was 68 months (5 months to 18 years). Fifteen patients (27.8%) were considered clinically cured. During follow-up, hospitalizations for wheezy exacerbations were reported in 35 patients (55%), and asthma diagnosed in 20 (37%). Chest CT scan improvement was noted in 25/44 (56.8%). Spirometry showed a persistent obstructive syndrome in 8/27 (29.6%). A sleep disorder was rare (2/36, 5.5%). Oxygen weaning occurred in 28 of the 45 patients initially treated (62.2%) and was age-dependent (35.7% under 2 years, 70.5% between 2 and 6 years, and 100% after 7 years). Oxygen duration was linked to a biopsy-proven diagnosis (p = 0.02) and to the use of a nutritional support (p = 0.003). Corticosteroids were largely prescribed at diagnosis, with no evident respiratory or nutritional effect during follow-up. Among 23 patients with an initial failure to thrive, 12 (52.2%) had no weight recovery. Initial enteral feeding (17/54, 31.5%) was stopped at a mean age of 43 months (3 to 120), with no effect on cure and oxygen liberation at the last visit.  Conclusion: Our results show that NEHI has a globally positive, but unequal, improvement over time. Further prospective studies are needed to better clarify the different trajectories of patients with NEHI. What is Known: • Neuroendocrine cell hyperplasia of infancy (NEHI) is an interstitial lung disease whose long-term outcome is considered positive from very few studies including heterogeneous populations. What is New: • The 68-month follow-up of our 54-patient cohort showed respiratory/nutritional symptom persistence in 72.2%, oxygen requiring in 34%, and asthma in 37%. When controlled, radiological or functional improvement was noted in 56.8 and 40.7%. Further prospective studies are needed to better clarify the different trajectories of patients with NEHI.

Efficacy and Safety of Elexacaftor/Tezacaftor/Ivacaftor in Children 6 Through 11 Years of Age with Cystic Fibrosis Heterozygous for F508del and a Minimal Function Mutation: A Phase 3b, Randomized, Placebo-controlled Study.

Rationale: The triple-combination regimen elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) was shown to be safe and efficacious in children aged 6 through 11 years with cystic fibrosis and at least one F508del-CFTR allele in a phase 3, open-label, single-arm study. Objectives: To further evaluate the efficacy and safety of ELX/TEZ/IVA in children 6 through 11 years of age with cystic fibrosis heterozygous for F508del and a minimal function CFTR mutation (F/MF genotypes) in a randomized, double-blind, placebo-controlled phase 3b trial. Methods: Children were randomized to receive either ELX/TEZ/IVA (n = 60) or placebo (n = 61) during a 24-week treatment period. The dose of ELX/TEZ/IVA administered was based on weight at screening, with children <30 kg receiving ELX 100 mg once daily, TEZ 50 mg once daily, and IVA 75 mg every 12 hours, and children ⩾30 kg receiving ELX 200 mg once daily, TEZ 100 mg once daily, and IVA 150 mg every 12 hours (adult dose). Measurements and Main Results: The primary endpoint was absolute change in lung clearance index2.5 from baseline through Week 24. Children given ELX/TEZ/IVA had a mean decrease in lung clearance index2.5 of 2.29 units (95% confidence interval [CI], 1.97-2.60) compared with 0.02 units (95% CI, -0.29 to 0.34) in children given placebo (between-group treatment difference, -2.26 units; 95% CI, -2.71 to -1.81; P < 0.0001). ELX/TEZ/IVA treatment also led to improvements in the secondary endpoint of sweat chloride concentration (between-group treatment difference, -51.2 mmol/L; 95% CI, -55.3 to -47.1) and in the other endpoints of percent predicted FEV1 (between-group treatment difference, 11.0 percentage points; 95% CI, 6.9-15.1) and Cystic Fibrosis Questionnaire-Revised Respiratory domain score (between-group treatment difference, 5.5 points; 95% CI, 1.0-10.0) compared with placebo from baseline through Week 24. The most common adverse events in children receiving ELX/TEZ/IVA were headache and cough (30.0% and 23.3%, respectively); most adverse events were mild or moderate in severity. Conclusions: In this first randomized, controlled study of a cystic fibrosis transmembrane conductance regulator modulator conducted in children 6 through 11 years of age with F/MF genotypes, ELX/TEZ/IVA treatment led to significant improvements in lung function, as well as robust improvements in respiratory symptoms and cystic fibrosis transmembrane conductance regulator function. ELX/TEZ/IVA was generally safe and well tolerated in this pediatric population with no new safety findings.

Cumulative Incidence and Risk Factors for Severe Coronavirus Disease 2019 in French People With Cystic Fibrosis.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections are closely monitored in people with cystic fibrosis (pwCF), especially severe cases. Previous studies used hospitalization rates as proxy for severity. METHODS: We evaluated data from coronavirus disease 2019 (COVID-19) cases diagnosed in French pwCF over the first pandemic year. Objective criteria were applied for defining severity (eg, respiratory failure and/or death). Data were compared to all French pwCF using the National Registry. RESULTS: As of 30 April 2021, 223 pwCF were diagnosed with COVID-19, with higher risks in adults (odds ratio [OR], 2.52 [95% confidence interval {CI}, 1.82-3.48]) and transplant recipients (OR, 2.68 [95% CI, 1.98-3.63]). Sixty (26.9%) patients were hospitalized, with increased risk in transplant recipients (OR, 4.74 [95% CI, 2.49-9.02]). In 34 (15%) cases, COVID-19 was considered severe; 28 (46.7%) hospitalizations occurred without objective criteria of severity. Severe cases occurred mostly in adult (85.3%) and posttransplant pwCF (61.8%; OR, 6.02 [95% CI, 2.77-13.06]). In nontransplanted pwCF, risk factors for severity included low lung function (median percentage of predicted forced expiratory volume in 1 second, 54.6% vs 75.1%; OR, 1.04 [95% CI, 1.01-1.08]) and CF-related diabetes (OR, 3.26 [95% CI, 1.02-10.4]). While 204 cases fully recovered, 16 were followed for possible sequelae, and 3 posttransplant females died. CONCLUSIONS: Severe COVID-19 occurred infrequently during the first pandemic year in French pwCF. Nontransplanted adults with severe respiratory disease or diabetes and posttransplant individuals were at risk for severe COVID-19. Thus, specific preventive measures should be proposed.

French national cohort of neuroendocrine cell hyperplasia of infancy (FRENCHI) study: diagnosis and initial management.

Early diagnosis of neuroendocrine cell hyperplasia of infancy (NEHI) is crucial as, conversely to the other causes of intersititial lung disease, corticosteroids are not recommended. Diagnosis is historically based on lung biopsy (NEHI), but in current practice, a clinical and radiological approach is more and more preferred (NEHI syndrome). This national study aimed to address diagnosis and initial management of patients followed up for a NEHI pattern in pediatric centers for rare lung diseases (RespiRare, France). Data on neonatal and familial events, symptoms at diagnosis, explorations performed and results, and therapeutic management were collected by questionnaire. Fifty-four children were included (boys 63%). The mean onset of symptoms was 3.8 ± 2.6 months. The most frequent symptoms at diagnosis were tachypnea (100%), retraction (79.6%), crackles (66.7%), and hypoxemia (59.3%). The mean NEHI clinical score, evocative when ≥ 7/10, was 7.9 ± 1.4 (76% with a score ≥ 7). All chest CT-scans showed ground glass opacities evolving at least the middle lobe and the lingula. Lung biopsy was performed in 38.9% of the cases and was typical of NEHI in only 52.4%, even when the clinical presentation was typical. Initial treatments were oxygen (83.6%) and more curiously intravenous pulses of steroids (83.3%) and azithromycin (70.2%). CONCLUSION: This national cohort of patients underlines diagnosis difficulties of NEHI. A composite clinical and radiological score should help clinicians for limiting the use of anti-inflammatory drugs. WHAT IS KNOWN: •Neuroendocrine cell hyperplasia of infancy (NEHI) is an interstitial lung disease whose diagnosis is essential to limit corticosteroids therapy. WHAT IS NEW: •In this national cohort of 54 patients with a NEHI pattern, diagnosis is mainly based on clinical symptoms and chest CT-scan results. The newly proposed clinical score and, when performed, the lung biopsies are faulted in 25 and 50% of the cases, respectively. •Corticosteroids are widely used. Such results plead for a new composite score to formally diagnose NEHI.

Population Pharmacokinetic Modeling and Dosing Simulations of Tobramycin in Pediatric Patients with Cystic Fibrosis.

Initial dosing and dose adjustment of intravenous tobramycin in children with cystic fibrosis (CF) is challenging. The objectives of this study were to develop nonparametric population pharmacokinetic (PK) models of tobramycin in children with CF to be used for dosage design and model-guided therapeutic drug monitoring. We performed a retrospective analysis of tobramycin PK data in our children's CF center. The Pmetrics package was used for nonparametric population PK analysis and dosing simulations. Both the ratios of maximal concentration to the MIC (Cmax/MIC) and daily area under the concentration-time curve to the MIC (AUC24/MIC) were considered efficacy targets. Trough concentration (Cmin) was considered the safety target. A total of 2,884 tobramycin concentrations collected in 195 patients over 9 years were analyzed. A two-compartment model including total body weight, body surface area, and creatinine clearance as covariates best described the data. A simpler model was also derived for implementation in the BestDose software to perform Bayesian dose adjustment. Both models were externally validated. PK/pharmacodynamics (PD) simulations with the final model suggest that an initial dose of tobramycin of 15 to 17.5 mg/kg/day was necessary to achieve Cmax/MICs of ≥10 for MICs up to 2 mg/liter in most patients. The AUC24/MIC target was associated with higher dosage requirements and higher Cmin. A daily dose of 12.5 mg/kg would optimize both efficacy and safety target attainment. We recommend performing tobramycin therapeutic drug monitoring (TDM), model-based dose adjustment, and MIC determination to individualize intravenous tobramycin therapy in children with CF.

Using chest CT scan and unsupervised machine learning for predicting and evaluating response to lumacaftor-ivacaftor in people with cystic fibrosis.

OBJECTIVES: Lumacaftor-ivacaftor is a cystic fibrosis transmembrane conductance regulator (CFTR) modulator known to improve clinical status in people with cystic fibrosis (CF). This study aimed to assess lung structural changes after one year of lumacaftor-ivacaftor treatment, and to use unsupervised machine learning to identify morphological phenotypes of lung disease that are associated with response to lumacaftor-ivacaftor. METHODS: Adolescents and adults with CF from the French multicenter real-world prospective observational study evaluating the first year of treatment with lumacaftor-ivacaftor were included if they had pretherapeutic and follow-up chest computed tomography (CT)-scans available. CT scans were visually scored using a modified Bhalla score. A k-mean clustering method was performed based on 120 radiomics features extracted from unenhanced pretherapeutic chest CT scans. RESULTS: A total of 283 patients were included. The Bhalla score significantly decreased after 1 year of lumacaftor-ivacaftor (-1.40±1.53 points compared with pretherapeutic CT; p<0.001). This finding was related to a significant decrease in mucus plugging (-0.35±0.62 points; p<0.001), bronchial wall thickening (-0.24±0.52 points; p<0.001) and parenchymal consolidations (-0.23±0.51 points; p<0.001). Cluster analysis identified 3 morphological clusters. Patients from cluster C were more likely to experience an increase in percent predicted forced expiratory volume in 1 sec (ppFEV1) ≥5 under lumacaftor-ivacaftor than those in the other clusters (54% of responders versus 32% and 33%; p=0.01). CONCLUSION: One year treatment with lumacaftor-ivacaftor was associated with a significant visual improvement of bronchial disease on chest CT. Radiomics features on pretherapeutic CT scan may help in predicting lung function response under lumacaftor-ivacaftor.

Real-Life Safety and Effectiveness of Lumacaftor-Ivacaftor in Patients with Cystic Fibrosis.

Rationale: Lumacaftor-ivacaftor is a CFTR (cystic fibrosis transmembrane conductance regulator) modulator combination recently approved for patients with cystic fibrosis (CF) homozygous for the Phe508del mutation.Objectives: To evaluate the safety and effectiveness of lumacaftor-ivacaftor in adolescents (≥12 yr) and adults (≥18 yr) in a real-life postapproval setting.Methods: The study was conducted in the 47 CF reference centers in France. All patients who initiated lumacaftor-ivacaftor from January 1 to December 31, 2016, were eligible. Patients were evaluated for lumacaftor-ivacaftor safety and effectiveness over the first year of treatment following the French CF Learning Society's recommendations.Measurements and Main Results: Among the 845 patients (292 adolescents and 553 adults) who initiated lumacaftor-ivacaftor, 18.2% (154 patients) discontinued treatment, often owing to respiratory (48.1%, 74 patients) or nonrespiratory (27.9%, 43 patients) adverse events. In multivariable logistic regression, factors associated with increased rates of discontinuation included adult age group, percent predicted FEV1 (ppFEV1) less than 40%, and numbers of intravenous antibiotic courses during the year before lumacaftor-ivacaftor initiation. Patients with continuous exposure to lumacaftor-ivacaftor showed an absolute increase in ppFEV1 (+3.67%), an increase in body mass index (+0.73 kg/m2), and a decrease in intravenous antibiotic courses by 35%. Patients who discontinued treatment had significant decrease in ppFEV1, without improvement in body mass index or decrease in intravenous antibiotic courses.Conclusions: Lumacaftor-ivacaftor was associated with improvement in lung disease and nutritional status in patients who tolerated treatment. Adults who discontinued lumacaftor-ivacaftor, often owing to adverse events, were found at high risk of clinical deterioration.

The diagnosis of hypersensitivity to antibiotics is rarely confirmed by allergy work-up in cystic fibrosis patients.

Cystic fibrosis (CF) patients receive many antibiotic treatments for recurrent respiratory infections and frequently report antibiotic hypersensitivity reactions (HSRs). In this retrospective study, medical records of CF patients were reviewed to clarify the clinical features, the culprit antibiotics, and the prevalence of antibiotic HSRs in the CF population. From 601 CF patients, 95 suspected antibiotic HSRs occurred in 60 patients (prevalence of 10.0%). ß-Lactams were the most common inducers, but cotrimoxazole was also frequently involved. Seventy-six of 95 suspected HSRs were assessed by allergy workup including skin tests (43/76 reactions) and/or drug reintroduction as a full course of the culprit antibiotic (73 of 76 reactions). From the 43 suspected HSRs that were skin-tested, only three had positive skin tests and were not subjected to drug readministration. All the other 73 suspected HSRs received a full course of the culprit antibiotic: HSR symptoms recurred in 10 of 73 cases and therefore were considered as confirmed antibiotic HSRs; for the remaining 63 suspected HSRs that did not relapse after drug readministration, the diagnosis of antibiotic HSRs was excluded. In summary, 13 of 76 suspected HSRs were confirmed as antibiotic HSRs. The prevalence of suspected and confirmed antibiotic HSRs in CF patients appears similar to that reported in the general population. Of note, most of the antibiotic suspected HSRs are not confirmed after allergology workup. A complete allergy workup appears therefore crucial to make a correct diagnosis and to avoid unnecessary contraindication of major antibiotics.

Viral respiratory tract infections in young children with cystic fibrosis: a prospective full-year seasonal study.

BACKGROUND: Viral respiratory tract infections are common during early childhood. How they impact cystic fibrosis lung disease history in young children is poorly known. The principal aim of our study was to determinate respiratory tract infections frequency in this cystic fibrosis young population. Secondary outcomes were nature of viral agents recovered and impact of such infections. METHODS: We conducted a prospective cohort study of 25 children affected by cystic fibrosis and aged less than 2 years. Nasal samplings were taken systematically monthly or bimonthly with additional samples taken during respiratory tract infections episodes. Ten pathogens were tested by a combination of five duplex RT-PCRs or PCRs: influenza A and B, respiratory syncytial virus (RSV), metapneumovirus (MPV), rhinovirus/enterovirus (RV/EV)), coronavirus (HKU1, NL63, 229E and OC43), parainfluenza virus (1-4), adenovirus and bocavirus (Respiratory Multi-Well System MWS r-gene®, BioMérieux, Marcy l'Étoile, France). Cycle thresholds (CTs) were reported for all positive samples and considered positive for values below 40. Quantitative variables were compared using a nonparametric statistical test (Wilcoxon signed rank for paired comparisons). Pearson's correlation coefficient (r) was used to assess relationships between two variables. Statistical analyses were performed using SAS v9.4 (SAS Institute, Cary, NC, USA) or GraphPad Prism V6.00 (GraphPad Software, La Jolla, CA, USA). The significance level was set at 0.05. RESULTS: The mean age at inclusion was 9.6 ± 6.7 months. The patients had 3.4 ± 1.7 respiratory tract infections episodes per child per year. Forty-four respiratory tract infections (69%) were associated with virus: rhinovirus and enterovirus (RV/EV) were implied in 61% of them and respiratory syncytial virus (RSV) in 14%. Only one patient required hospitalization for lower respiratory tract infections. 86% of the patients were treated by antibiotics for a mean of 13.8 ± 6.2 days. RSV infections (n = 6) were usually of mild severity. CONCLUSIONS: Respiratory tract infections in young children with cystic fibrosis were of mild severity, rarely requiring hospitalization. Unsurprisingly, RV/EV were the most frequent agents. RSV-related morbidity seems low in this population. This raises the question of the usefulness of RSV preventive medication in this young population.

Nutritional Status in the First 2 Years of Life in Cystic Fibrosis Diagnosed by Newborn Screening.

OBJECTIVE: To evaluate nutritional status and associated factors in a cystic fibrosis (CF) cohort diagnosed by newborn screening and followed up to month 24. METHODS: A prospective longitudinal multicenter study assessing nutritional status according to pancreatic status, feeding modalities, prescriptions, pulmonary outcome, and biological nutritional parameters. RESULTS: One hundred and five infants were recruited and 99 completed the study. Nutritional care management prevented undernutrition and stunting in those with exocrine pancreatic sufficiency (EPS), but affected (13/87) 15% and (21/86) 24%, respectively, of infants with exocrine pancreatic insufficiency (EPI). The logistic regression model found a positive association between both weight and length z scores "at risk" at month 24, and initial pulmonary symptoms (odds ratio [OR] 0.06, P < 0.01 and OR 0.08, P < 0.01, respectively); these symptoms were less frequent when age at first visit was earlier than 1.2 months (33% vs 67%, P = 0.02); stunting was also associated with high-calorie density intake and Staphylococcus aureus (OR 0.05, P = 0.01 and OR 0.17, P < 0.01). Pulmonary outcome did not differ according to pancreatic status; breast-feeding for at least 3 months delayed first acquisition of Pseudomonas aeruginosa. Despite sodium and fat-soluble vitamin supplementation, half of both cohorts had low urinary sodium output and half of the EPI cohort had low vitamin D levels. CONCLUSIONS: Our data shed light on the fact that stunting was more frequent than undernutrition, while both parameters involved only patients with pancreatic insufficiency. Modalities of feeding were not associated with nutritional status; breast-feeding may provide some protection against acquisition of P aeruginosa.

Palivizumab prophylaxis in infants with cystic fibrosis does not delay first isolation of Pseudomonas aeruginosa or Staphylococcus aureus.

Respiratory syncytial virus (RSV) infections may worsen cystic fibrosis (CF) lung disease and favor Pseudomonas aeruginosa (Pa) or Staphylococcus aureus (Sa) acquisition, which is of particular importance in the youngest patients. We aimed to determine the effectiveness of PVZ on microbiological outcomes in young children with CF. We conducted a retrospective case-control study to compare these outcomes in children who systematically received PVZ (PVZ+; n = 40) or not (PVZ-; n = 140). One case was matched with at least three same-gender controls born the same year and month. Median (range) age at first Pa isolation was not statistically different between PVZ- (12.3 [3.8-32.6] months) and PVZ+ (10.4 [1.2-33.0] months; p = 0.953) patients. A similar trend was found for Sa (PVZ+: 6.4 [2.0-59.0] months; PVZ-: 3.8 [0.1-74.1] months; p = 0.191). The proportion of Pa isolations by 3 years of age did not differ between groups (PVZ+ 40% vs. PVZ- 41.4%), but this proportion was higher for Sa in the PVZ+ group (97%) than in the PVZ- group (85%; p = 0.001). Healthcare consumption and growth outcomes did not significantly differ between groups. CONCLUSION: Systematic PVZ use did not delay key pathogen acquisition in young children with CF. What is known: • Palivizumab is the only available monoclonal antibody against respiratory syncytial virus infection. • Whether or not it is useful in infants with cystic fibrosis remains controversial. What is new: • Palivizumab does not delay key pathogens (Pseudomonas aeruginosa, Staphylococcus aureus) first isolation in young children with cystic fibrosis. • Palivizumab does not reduce healthcare consumption or improve growth during the first 3 years of life of young children with cystic fibrosis.

A French multicentric study and review of pulmonary Nocardia spp. in cystic fibrosis patients.

Some bacterial species recovered from the airways of cystic fibrosis (CF) patients are indisputably associated with lung infections, whereas the clinical relevance of others, such as Nocardia spp., remains unclear. Sixteen French CF cases of colonization/infection with Nocardia spp. were reviewed in order to evaluate the epidemiology, the clinical impact and the potential treatment of these bacteria, and results were compared to those of the literature. Five Nocardia species were identified, Nocardia cyriacigeorgica being the major species (50 % of cases). At first isolation, Nocardia was the sole pathogen recovered in six patients. Seven patients presented pulmonary exacerbation. For 12 patients, antimicrobial treatment against Nocardia was started immediately, mainly based on cotrimoxazole (6 of the 12 cases). In this study, we highlight the heterogeneity of the clinical management of Nocardia spp. in CF. Guidelines for the clinical management of Nocardia infections in CF patients are proposed.

Sweat test practice in pediatric pulmonology after introduction of cystic fibrosis newborn screening.

The influence of the generalization of cystic fibrosis newborn screening (CFNBS) in France on sweat test (ST) prescription is unknown. In this French retrospective, descriptive, and multicenter study, we studied the indications, number, methods, and results of STs prescribed by a pediatric pulmonologist in children who had a negative CFNBS and an ST for respiratory symptoms in 2012. We included 502 children with 523 STs, performed with four different methods. The main indication was asthma (71.3 %), then chronic cough (52.4 %), atypical lower airway infections (42.2 %), and bronchiectasis (7 %). Four children had a diagnosis of CF (0.8 %), all presenting with chronic productive cough and recurrent respiratory infections. CONCLUSION: Asthma is the most frequent indication of ST in our cohort. Because of the systematic CFNBS in France, some prescriptions should be avoided, particularly in case of severe or moderate asthma with no other associated symptom. Moreover, methods of STs often do not follow the guidelines and need standardization. WHAT IS KNOWN: • Newborn screening (NBS) has become the most frequent circumstance of the diagnosis of cystic fibrosis (CF) in France after its generalization. • The prescription of sweat test (ST) in children with respiratory symptoms who already had a negative NBS has not been studied. WHAT IS NEW: • In children with a negative CF NBS referred to a university hospital for respiratory diseases, despite important variations of ST methods, only 4 children among 502 have been diagnosed as CF. • Despite recommendations, ST prescription should be avoided in children with moderate to severe asthma and no other associated symptom.