ObjectiveAlpha-1-antitrypsin deficiency is a relatively prevalent, but under-diagnosed, genetic disease. The objective of this study was to assess whether the systematic screening for alpha-1-antitrypsin deficiency in all patients with chronic obstructive pulmonary disease from a tertiary service has an impact on the number of patients being diagnosed with this condition.ResultsChronic obstructive pulmonary disease patients were screened for alpha-1-antitrypsin deficiency using immunonephelometry. The presence of a mutation was confirmed by molecular study of the SERPINA1 gene or by genetic sequencing, as needed. A total of 551 patients with chronic obstructive pulmonary disease were analyzed. Among these, 40 (7.2%) had some genetic mutation, while 11 (2%) had a Pi*ZZ genotype, resulting in severe respiratory illness. The systematic evaluation of chronic obstructive pulmonary disease patients revealed that screening is an effective method to diagnose alpha-1-antitrypsin deficiency. Early diagnosis may facilitate smoking cessation and initiation of treatment to maintain lung function.

We describe three cases of female subjects (aged 16, 44 and 41 years) with no respiratory symptoms, who have alpha-1 antitripsyn mutation (PiSZ, PiZZ and PiZZ) and who performed traditional pulmonary function tests and the single breath nitrogen washout test. They still did not have chronic obstructive pulmonary disease (COPD) or any identifiable change in traditional pulmonary function tests but already have change in nitrogen washout tests. Alpha-1 antitrypsin deficiency is a genetic disorder associated with early-onset COPD. There is evidence that although patients who have well-preserved FEV1 may already have signs of emphysema associated with symptoms. Therefore, the nitrogen washout test is considered to have more sensitive outcomes than other pulmonary function tests for early investigation of small airways disease and could allow the monitoring pulmonary function and evaluating of therapeutic decision.

Introduction: Small airways are not evaluated with traditional pulmonary function tests. The aim of this study was to evaluate the small airways in patients with chronic obstructive pulmonary disease (COPD) with a nitrogen washout test and to verify whether there is a difference between patients with COPD due to smoking and those with COPD due to alpha-1 antitrypsin mutation. Methods: Sixteen patients with mutation in the SERPINA1 gene and 45 patients with no mutation were included in this cross-sectional study. All pulmonary function tests, including the single breath nitrogen washout test, were performed for all patients and alpha-1 antitrypsin dosage was assessed with immunonephelometry. Results: A comparison of patients with COPD due to smoking and those with COPD due to smoking and mutation revealed a significant difference in closure volume (%), which was the poorest in the mutation group. In the group with COPD and mutation, there was an inverse correlation between smoking and closure volume (%). We also verified that similar to forced expiratory volume in the first second (FEV1), the phase III slope (%) and ΔN2 750-1250 mL (%) could be used to differentiate the severity of airflow limitation. Conclusion: Our results suggest that both variables, phase III slope and the ΔN2 750-1250 mL (%), could be related to COPD severity. Therefore, alterations at the distribution of the location of the emphysema could alter the results of closer volume and that the nitrogen washout test is more sensitive when compared to traditional pulmonary function test in evaluating COPD patients.

Background Combined pulmonary fibrosis and emphysema (CPFE) is an entity characterized by the presence of emphysema in upper lobes and fibrosis in lower lobes. Due to the presence of the two diseases concomitantly, it may be difficult to diagnose. This study aims at a better understanding of this entity and proposes biological markers (functional and biochemical) that help in this characterization. Methods A prospective, observational, cross-sectional study was carried out at a reference center. Pulmonary function tests (spirometry, CO-diffusion capacity, plethysmography and single-maneuver nitrogen washout test - SBWN 2 ) and biochemical markers (periostin, mucin-16, PDGF-BB and TGF-β 1 ) were measured in groups of patients: idiopathic pulmonary fibrosis, CPFE and chronic obstructive pulmonary disease (COPD). Results Variables derived from SBWN 2 - closing volume (CV) / vital capacity (VC) (%) and closing capacity (CC) / total lung capacity (TLC) (%) - were found to be higher in the CPFE group compared to the Idiopathic pulmonary fibrosis (IPF) group (CV/VC%: 0.25 (0.12 – 11.01) and 13.05 (0.21 – 20.73); p = 0.005; CC/TLC%: 30.1 (22.4 – 37.47) and 33.69 (32.05 – 41.98); p = 0.03, respectively). Periostin was higher in the CPFE group than in the other groups [CPFE: 66.74 (45.21 – 90.5), IPF: 43.81 (31.97 – 56.18), COPD: 40.08 (20.66 – 50.81); p = 0.0002], and mucin-16 was higher in the IPF group than in the CPFE group [CPFE: 13.59 (4.16 – 28.16); IPF: 71.94 (40.46 - 164); COPD: 25.85 (9.27 – 30.29); p = 0.02]. Conclusions Findings show that CPFE presents different functional and biochemical characteristics than IPF, including higher CV/VC%, CC/TLC% and periostin, whereas mucin-16 was higher in the IPF.