Bronchoalveolar lavage, sputum and exhaled clinically relevant inflammatory markers: values in healthy adults

Abstract

Bronchoalveolar lavage (BAL), induced sputum and exhaled breath markers (exhaled nitric oxide and exhaled breath condensate) can each provide biological insights into the pathogenesis of respiratory disorders. Some of their biomarkers are also employed in the clinical management of patients with various respiratory diseases. In the clinical context, however, defining normal values and cut-off points is crucial. The aim of the present review is to investigate to what extent the issue of defining normal values in healthy adults has been pursued for the biomarkers with clinical value.The current authors reviewed data from literature that specifically addressed the issue of normal values from healthy adults for the four methodologies.Most studies have been performed for BAL (n59), sputum (n53) and nitric oxide (n53). There are no published studies for breath condensate, none of whose markers yet has clinical value. In healthy adult nonsmokers the cut-off points (mean+2SD) for biomarkers with clinical value were as follows. BAL: 16.7% lymphocytes, 2.3% neutrophils and 1.9% eosinophils; sputum: 7.7610 6 ?mL -1 total cell count and 2.2% eosinophils; nitric oxide: 20.2 ppb. The methodologies differ concerning the quantity and characteristics of available reference data. Studies focusing on obtaining reference values from healthy individuals are still required, more evidently for the new, noninvasive methodologies.

Exhaled breath condensate: a comprehensive update

“…4 Glass CMD Healthy subjects, n = 20, p = 0.042 [ 26 ] Nitrate/nitrite (concentration) = − 20 vs. 4 Glass CMD Healthy subjects, n = 20, p = 0.63 [ 26 ] TURBO-DECCS, transportable unit for research on biomarkers obtained from disposable exhaled condensate collection systems; CMD, custom-made device; a more acidic.…”

“…They are categorised into cysteinyl leukotrienes (i.e., LTC 4 , LTD 4 and LTE 4 ) and LTB 4 . Cysteinyl leukotrienes contract airway smooth muscle, increase vascular permeability, stimulate mucus secretion and decrease mucociliary clearance [ 79 ].…”

“…Due to the inefficiency of argon and CO 2 in removing other volatile ions and oral contaminants, including NH 4 + /NH 3 , some have suggested lyophilisation as the method of choice for removing volatile ions [ 50 , 51 ]. EBC pH of lyophilised samples will be a direct measurement of non-volatile acids, such as lactic acid, that originate from epithelial fluid [ 50 ].…”

Inhibition of airway proteases in cystic fibrosis lung disease

“…Normal values for induced sputum cellular counts and composition have been established in both adults and children [89,90]. In CF patients, a limited number of studies have been performed involving a broad range of CF subjects (discussed further later).…”

Markers of airway inflammation in pulmonary diseases assessed by induced sputum

“…Reference values and the distribution of cell counts in induced sputum have been provided in a large number of healthy volunteers [6,7]. The induced sputum was found rich in macrophages and neutrophils and poor in eosinophils, lymphocytes and epithelial cells.…”