BACKGROUND: Impulse oscillometry (IOS) is a noninvasive technique that measures lung physiology independently of patient effort. In the present study, we aimed to investigate the utility of IOS parameters in comparison with pulmonary function testing (PFT) among hospitalized subjects, with emphasis on obstructive and small airway diseases. METHODS: Sixty-one subjects hospitalized either with unexplained dyspnea or for pre-surgery evaluation were included in the study. All subjects underwent PFTs and IOS test. The correlation between IOS results and PFTs was examined in different subgroups. The ability of IOS parameters to predict abnormal PFTs was evaluated using the area under the receiver operating characteristic (ROC) curve, and optimal cutoff values were calculated. RESULTS: IOS results were found to correlate with PFT values. Subgroup analysis revealed that these correlations were higher in younger (age < 70) and non-obese (body mass index < 25kg/m ² ) subjects. The resonant frequency was an independent predictor and had the best predictive ability for abnormal FEV ₁ /FVC (area under the ROC curve 0.732 [95% CI 0.57–0.90], optimal cutoff 17 Hz, 87% sensitivity, 62% specificity) and abnormal forced expiratory flow during the middle half of the FVC maneuver (area under the ROC curve 0.667 [95% CI 0.53–0.81], optimal cutoff 15 Hz, 77% sensitivity, 54% specificity). Area of reactance and the difference in respiratory resistance at 5 Hz and 20 Hz also showed a good predictive ability for abnormal FEV ₁ /FVC (area under the ROC curve 0.716 and 0.730, respectively). CONCLUSIONS: We found that the IOS performed well in diagnosing small airway and obstructive diseases among hospitalized subjects. IOS might serve as an alternative to standard PFTs in non–cooperative or dyspneic hospitalized patients.

Hypersensitivity pneumonitis (HP) is a heterogeneous interstitial lung disease (ILD) that may be difficult to confidently diagnose. Recently, the 2020 ATS/JRS/ALAT HP diagnostic guidelines were published, yet data validating their performance in real-life settings are scarce. We aimed to assess the diagnostic performance of the HP guidelines compared to the gold-standard multidisciplinary discussion (MDD). For this purpose, we included consecutive ILD patients that underwent diagnostic bronchoscopy between 2017 and 2020 in three large medical centers. Four diagnostic factors (antigen exposure history, chest computed tomography pattern, bronchoalveolar lavage lymphocyte count, and histology results) were used to assign guidelines-based HP diagnostic confidence levels for each patient. A sensitivity analysis was performed, with MDD diagnosis as the reference standard. Overall, 213 ILD patients were included, 45 (21%) with an MDD diagnosis of HP. The guidelines’ moderate (≥70%) confidence threshold produced optimal performance with 73% sensitivity for HP, 89% specificity, and a J-index of 0.62. The area under the receiver operating characteristic curve (AUC) for a correct guidelines-based diagnosis was 0.86. The guidelines had better performance for non-fibrotic than fibrotic HP (AUC 0.92 vs. 0.82). All diagnostic factors, except bronchoalveolar lavage lymphocyte count, were independent predictors for MDD diagnosis of HP in a multivariate analysis. In conclusion, the HP guidelines exhibited a good diagnostic performance compared to MDD diagnosis in real-life setting.

Hospitalized patients with a high suspicion of pulmonary tuberculosis (HS-PTB) are isolated until a definite diagnosis can be determined. If doubt remains after negative sputum samples, bronchoscopy with bronchoalveolar lavage (BAL) is often sought. Still, evidence of the added value of BAL in this patient population is scarce. To address this issue, we included consecutive HS-PTB patients with negative sputum samples who underwent BAL between 2017 and 2018. Chest X-rays (CXR) and CT scans were evaluated by a chest radiologist blind to the final diagnosis. Independent predictors for PTB were assessed by multivariate regression, using all positive PTB patients between 2017 and 2019 (by sputum or BAL) as a control group (n = 41). Overall, 42 HS-PTB patients were included (mean age 51 ± 9, 36% female). BAL was a viable diagnostic for PTB in three (7%) cases and for other clinically relevant pathogens in six (14%). Independent predictors for PTB were ≥2 sub-acute symptoms (adjusted OR 3.18, 95% CI 1.04–9.8), CXR upper-lobe consolidation (AOR 8.70, 95% CI 2.5–29), and centrilobular nodules in chest CT (AOR 3.96, 95% CI 1.20–13.0, p = 0.02). In conclusion, bronchoscopy with BAL in hospitalized patients with HS-PTB had a 7% added diagnostic value after negative sputum samples. Our findings highlight specific predictors for PTB diagnosis that could be used in future controlled studies to personalize the diagnostic evaluation.

BACKGROUND: COPD exacerbations are a major cause of morbidity and mortality. Although inhaled corticosteroids (ICS) have a role as long-term treatment, their efficacy in exacerbations, particularly as an adjunct to systemic steroids, remains unclear. METHODS: In this retrospective observational study, we analyzed data from 870 subjects admitted with COPD exacerbations to a tertiary medical center in Israel from January 2018–January 2023. We investigated the impact of adding ICS to standard systemic steroid treatment on hospital length of stay, intubation rates, and 30-d mortality using propensity score matching to account for confounders. RESULTS: The cohort, after matching, included 354 subjects treated with systemic steroids and ICS and 121 treated with systemic steroids alone. All characteristics were similar between the groups. Our analysis showed no differences in 30-d mortality (7.1% vs 5.8%, P = .63) or secondary outcomes (intubation, hospital length of stay, and readmission rates) between the groups. Subgroup analyses based on different eosinophil levels did not alter these findings. In multivariate analysis among the general cohort, eosinophil count < 150 cells/μL (adjusted odds ratio 0.45 [95% CI 0.21–0.87], P = .02) and high Charlson score (adjusted odds ratio 1.19 [95% CI 1.02–1.37], P = .02) were independent predictors for 30-d mortality. CONCLUSIONS: Despite the known benefits of ICS in managing chronic COPD, we did not find an added value of ICS to systemic steroids in exacerbations. These results underscore the necessity for individualized treatment strategies and further research into the role of ICS in COPD exacerbations.

Cardiovascular comorbidities complicate interstitial lung disease (ILD) and represent potential therapeutic targets, yet the prevalence and clinical impact of left ventricular diastolic dysfunction (LVDD) remain poorly characterized. We aimed to evaluate LVDD as a potential treatable trait within a prospective cohort. Using data from an ILD registry (January 2021–October 2024), we defined clinically relevant LVDD as echocardiographic grade 2 or 3 diastolic dysfunction. Out of 276 patients (median age 69, 44% female), 14% had LVDD, which was almost entirely in patients with fibrosis (97%, p = 0.045) and associated with lower diffusing capacity for carbon monoxide. Survival and clinical analyses restricted to the fibrotic ILD subgroup (n = 241) showed that LVDD was independently associated with a higher hazard for a combined adverse outcome of acute exacerbation, lung transplantation, or death (adjusted HR 1.82, 95% CI 1.03–3.38, p = 0.043), which persisted after 1:2 propensity score matching (HR 2.04). LVDD also independently predicted increased all-cause mortality (adjusted HR 2.10) and reduced 6-min walk distance (median 413 vs. 465 m, β = −0.14, p = 0.036). In conclusion, LVDD is prevalent in fibrotic ILD and carries significant prognostic implications. Given its objective measurability and actionable treatment pathways, LVDD represents a potentially important treatable trait requiring multi-disciplinary care.