Respiratory infections are associated with the majority of COPD exacerbations and their severity, especially those with viral/bacterial coinfection. Airway neutrophilia is related to exacerbation severity regardless of viral and/or bacterial infections. Eosinophilia is a good predictor of viral exacerbations.

To determine whether patients with fixed airflow obstruction have distinct pathologic and functional characteristics depending on a history of either asthma or chronic obstructive pulmonary disease (COPD), we characterized 46 consecutive outpatients presenting with fixed airflow obstruction by clinical history, pulmonary function tests, exhaled nitric oxide, sputum analysis, bronchoalveolar lavage, bronchial biopsy, and high-resolution computed tomography chest scans. Subjects with a history of COPD (n = 27) and subjects with a history of asthma (n = 19) had a similar degree of fixed airflow obstruction (FEV1: 56 +/- 2 versus 56 +/- 3% predicted) and airway hyperresponsiveness (PC20FEV1: 2.81 [3.1] versus 1.17 [3.3]). Subjects with a history of asthma had significantly more eosinophils in peripheral blood, sputum, bronchoalveolar lavage, and airway mucosa; fewer neutrophils in sputum and bronchoalveolar lavage fluid; a higher CD4+/CD8+ ratio of T cells infiltrating the airway mucosa; and a thicker reticular layer of the epithelial basement membrane. They also had significantly lower residual volume, higher diffusing capacity, higher exhaled nitric oxide, lower high-resolution computed tomography scan emphysema score, and greater reversibility to bronchodilator and steroids. In conclusion, despite similar fixed airflow obstruction, subjects with a history of asthma have distinct characteristics compared with subjects with a history of COPD and should be properly identified and treated.

BackgroundHistology is a key element for the multidisciplinary diagnosis of fibrotic diffuse parenchymal lung diseases (f-DPLD) when the clinical-radiological picture is nondiagnostic. Transbronchial lung cryobiopsy (TBLC) have been shown to be useful for obtaining large and well-preserved biopsies of lung parenchyma, but experience with TBLC in f-DPLD is limited.ObjectivesTo evaluate safety, feasibility and diagnostic yield of TBLC in f-DPLD.MethodProspective study of 69 cases of TBLC using flexible cryoprobe in the clinical-radiological setting of f-DPLD with nondiagnostic high resolution computed tomography (HRCT) features.ResultsSafety: pneumothorax occurred in 19 patients (28%). One patient (1.4%) died of acute exacerbation. Feasibility: adequate cryobiopsies were obtained in 68 cases (99%). The median size of cryobiopsies was 43.11 mm2 (range, 11.94–76.25). Diagnostic yield: among adequate TBLC the pathologists were confident (“high confidence”) that histopathologic criteria sufficient to define a specific pattern in 52 patients (76%), including 36 of 47 with UIP (77%) and 9 nonspecific interstitial pneumonia (6 fibrosing and 3 cellular), 2 desquamative interstitial pneumonia/respiratory bronchiolitis–interstitial lung disease, 1 organizing pneumonia, 1 eosinophilic pneumonia, 1 diffuse alveolar damage, 1 hypersensitivity pneumonitis and 1 follicular bronchiolitis. In 11 diagnoses of UIP the pathologists were less confident (“low confidence”). Agreement between pathologists in the detection of UIP was very good with a Kappa coefficient of 0.83 (95% CI, 0.69–0.97). Using the current consensus guidelines for clinical-radiologic-pathologic correlation 32% (20/63) of cases were classified as Idiopathic Pulmonary Fibrosis (IPF), 30% (19/63) as possible IPF, 25% (16/63) as other f-DPLDs and 13% (8/63) were unclassifiable.ConclusionsTBLC in the diagnosis of f-DPLD appears safe and feasible. TBLC has a good diagnostic yield in the clinical-radiological setting of f-DPLD without diagnostic HRCT features of usual interstitial pneumonia. Future studies should consider TBLC as a potential alternative to SLBx in f-DPLD.

We investigated the relationship between the reversibility of airflow limitation, the concentration of nitric oxide (NO) in exhaled air, and the inflammatory cells in the sputum of patients with stable chronic obstructive pulmonary disease (COPD). We examined nine normal healthy control subjects and 20 nonatopic patients with COPD. Ten patients had no reversibility of airflow limitation (increase in FEV(1) of < 12% and < 200 ml after 200 microg of inhaled salbutamol), and 10 patients had partial reversibility of airflow limitation (increase in FEV(1) of < 12% but > 200 ml after 200 microg of inhaled salbutamol). Exhaled NO levels were higher in COPD patients with partial reversibility of airflow limitation than in those with no reversibility of airflow limitation (median 24 [interquartile range 15.3 to 32] ppb versus 8.9 [4.6 to 14.7] ppb; p < 0.01). Compared with healthy control subjects, only COPD patients with partial reversibility of airflow limitation had increased concentrations of sputum eosinophils. We conclude that, in patients with stable COPD, even a partial bronchodilator response to inhaled salbutamol is associated with increased exhaled NO and sputum eosinophilia, suggesting that these patients may have a different response to treatment than do those without reversible airflow limitation.