Changes in PH in exhaled breath condensate after specific bronchial challenge test in patients with chronic hypersensitivity pneumonitis: a prospective study

Abstract

BackgroundThe aim of this study was to investigate the influence of the specific inhalation challenge (SIC) on changes of pH values in exhaled breath condensate (EBC) in patients with hypersensitivity pneumonitis (HP).MethodsA prospective study of 85 patients with suspected HP, of whom 63 were diagnosed with HP due to exposure to avian or fungal antigens. In all cases, EBC samples were collected before and after completion of the SIC and pH values were determined.ResultsTaken as a whole, patients with HP did not present changes in EBC pH after SIC. However, considering only patients with exposure to molds, those diagnosed with HP had a significantly more acid pH post-SIC than those with another diagnosis (p = 0.011). This fact is not observed in patients exposed to bird’s antigens. A ROC curve showed that a reduction in EBC pH of 0.3 units or more after SIC in patients diagnosed with HP due to exposure to molds had a sensitivity of 30 % (CI: 12.8 to 54.3 %) and a specificity of 100 % (CI: 65.5 to 100 %).ConclusionEBC pH may be useful in interpreting SIC results in patients with HP, especially in those patients exposed to molds. Further studies are now required to test the validity of these proposals.

Breath biomarkers in idiopathic pulmonary fibrosis: a systematic review

“…NO measured at this flow rate contains a higher proportion of airway and lower proportion of alveolar NO [54]. FeNO 50 did not show consistency in IPF, [55, 57] or other forms of interstitial lung disease [73, 74]. FeNO 50 levels in IPF patients ranged from 20.8–31.5 ppb [55, 57, 67].…”

“…C alv NO, but not FeNO, has also been reported to be elevated in ILD related to systemic sclerosis [78–80]. Increased exhaled NO levels have been described in other forms of ILD including hypersensitivity pneumonitis (HP), asbestosis and connective tissue disease related ILD (CTD-ILD), limiting the potential of the test as a discriminative diagnostic tool [73, 74, 81–85]. An alternative role for C alv NO may be in disease monitoring.…”

Quantitative assessment of specific serum IgGs may verify source of environmental exposure in extrinsic allergic alveolitis (EAA)

“…Samples were frozen at −80°C for storage. Antigenic extracts were prepared according to previously published studies (Ojanguren et al, 2015) and lyophilized (Telstar Cryodos 80, Telstar, Spain). Five milligrams of lyophilized extract was dissolved in 100 µl of deionized water.…”

A Review of the Usefulness of Non-invasive Exhaled Breath Condensate pH Analysis for Diseases Diagnosis with Elements of Meta-analysis: An Update from 2012

“…In the case of exposure to avian antigens, there were no statistically significant differences in pH changes between the HP populations and the population of patients with other diagnoses. Furthermore, the authors also suggested that EBC pH can be used to reduce the number of false negative results on SIC tests [62]. Further analysis will be necessary in order to fully assess the particular clinical implications of these results.…”