Daily Respiratory Research Analysis

BACKGROUND: Disentangling preschool wheezing heterogeneity in terms of clinical traits, temporal patterns, and collective health care burden is critical for precise and effective interventions. OBJECTIVE: We aimed to collectively define contributions and distinct characteristics of respiratory phenotypes based on longitudinal wheeze and atopic sensitization patterns in the first 5 years of life. METHODS: Group-based trajectory analysis was performed in the CHILD Cohort Study to identify distinct wheeze and allergic sensitization trajectories. Trajectories were evaluated for associated risk factors, health care utilization, biologic determinants, and clinical outcomes. Stool samples for shotgun metagenomic sequencing profiles of infant microbiomes collected at ages 3 months and 1 year were assessed for phenotype-specific biomarkers. RESULTS: A total of 6 distinct respiratory phenotypes were identified on the basis of samples from 2902 children; the phenotypes differed by temporal wheeze and allergic sensitization patterns. Although allergic wheeze phenotypes (found in 11.6% of participants) carried the highest risk of asthma diagnosis, the more common nonallergic phenotypes (in 88.3% of participants) contributed to the majority of 5-year asthma diagnoses (61.4% of diagnoses). Most importantly, nonallergic phenotypes accounted for more than two-thirds of health care utilization in this age group. Phenotypes differed by lung function, blood eosinophil counts, allergic comorbidities, and weight-for-age z score. Moreover, microbiome profiles developed from 1439 infants revealed that largely nonoverlapping microbial signatures at age 1 year are associated with each phenotype. CONCLUSION: We identified novel early-childhood respiratory phenotypes to disentangle nonoverlapping paths to preschool wheezing. Our findings highlight the continued clinical relevance of nonatopic wheeze phenotypes, which remain undertreated despite accounting for a substantial proportion of health care utilization and asthma diagnoses.

BACKGROUND: Interstitial lung disease (ILD) is a frequent manifestation of connective tissue diseases (CTDs) and is associated with high morbidity and mortality. Clinical practice guidelines to standardise screening, diagnosis, treatment and follow-up for CTD-ILD are of high importance for optimised patient care. METHODS: A European Respiratory Society and European Alliance of Associations for Rheumatology task force committee, composed of pulmonologists, rheumatologists, pathologists, radiologists, methodologists and patient representatives, developed recommendations based on PICO (Patients, Intervention, Comparison, Outcomes) questions with grading of the evidence according to the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) methodology and complementary narrative questions agreed on by both societies. For both PICO and narrative questions, the Evidence to Decision framework was used to formulate the recommendations. RESULTS: The task force committee concluded with recommendations for 25 PICO and 28 narrative questions, regarding ILD in the context of systemic sclerosis, rheumatoid arthritis (RA), idiopathic inflammatory myopathies, Sjögren disease (SjD), systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD). In four narrative questions, regarding screening and assessment of risk for ILD progression in MCTD, SjD and SLE and one PICO question regarding pirfenidone in CTD-ILD other than RA-ILD, the task force had insufficient evidence to support recommendations. Screening, diagnostic, monitoring and treatment algorithms were developed based on the recommendations and usual clinical practice. CONCLUSIONS: We provide practical guidance by evidence-based recommendations to clinicians for each of the CTDs. In many cases there is low certainty or absence of evidence and we encourage further research to fill these gaps.

OBJECTIVE: To identify distinct phenotypes of acute respiratory distress syndrome (ARDS) developing after hematopoietic cell transplantation (HCT), using routinely available clinical data at ICU admission. DESIGN: Multicenter retrospective cohort study using latent class analysis. SETTING: ICUs across three Mayo Clinic campuses (Minnesota, Florida, and Arizona). PATIENTS: A total of 166 adult patients who developed ARDS within 120 days following HCT (96 allogeneic, 70 autologous). INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Model selection was based on multiple metrics including Bayesian information criteria, entropy, and Vuong-Lo-Mendell-Rubin Likelihood Ratio testing. A two-class model optimally described the cohort. Class 1 (n = 81) was characterized by worse hypoxemia (P/F ratio 157 vs. 210, p = 0.002), higher Pco2 (41 vs. 36 mm Hg, p < 0.001), and higher bilirubin (1.4 vs. 0.9 mg/dL, p < 0.001) compared with class 2 (n = 85). Both classes included a mix of transplant types, transcending a simple autologous/allogeneic dichotomy, although class 1 had more allogeneic recipients (70.4% vs. 45.9%, p = 0.001). Although time-from-transplant was not a class-defining variable, class 1 occurred later after transplant (30.0 vs. 11.9 d, p < 0.001) with higher frequency of idiopathic pneumonia syndrome (14.8% vs. 2.4%, p = 0.004). Class 2 had more frequent neutropenia (leukocytes 0.4 vs. 5.9 × 109, p < 0.001) and higher frequency of peri-engraftment respiratory distress syndrome (29.4% vs. 9.9%, p = 0.005). Outcomes were significantly worse for class 1 (90-d mortality: 72.8% vs. 48.2%, p = 0.001). An exploratory parsimonious model had good classification accuracy (0.90) using just six variables: leukocyte count, platelet count, bilirubin, Pco2, body mass index, and temperature. CONCLUSIONS: ARDS after HCT comprises two distinct phenotypes with distinct clinical characteristics and outcomes. These phenotypes align with recognized post-HCT lung injury syndromes and may reflect different underlying biological processes. This framework provides a foundation for investigating targeted therapeutic approaches.