Inflammatory mediators in exhaled breath condensate of children with obstructive sleep apnea syndrome

BACKGROUND: Upper airway inflammation is now recognized in adults with obstructive sleep apnea (OSA) syndrome. However, the role played by eicosanoids such as leukotrienes and prostaglandins is unclear. OBJECTIVE: To investigate whether eicosanoids are measurable in exhaled breath condensate (EBC), and to determine whether differences in these inflammatory mediators emerge among children with and without sleep-disordered breathing (SDB). METHODS: EBC was collected from 50 consecutive snoring children undergoing overnight polysomnography for suspected SDB, and from 12 nonsnoring control subjects. Prostaglandin E2 (PGE2), leukotriene B4 (LTB4), and cysteinyl leukotrienes (cys-LTs: leukotriene C4 [LTC4]/leukotriene D4 [LTD4]/leukotriene E4 [LTE4]) EBC levels were analyzed using enzyme-linked immunosorbent assay. RESULTS: LTB4 levels were elevated in children with an apnea-hypopnea index (AHI) > 5/h (SDB; 97.6 +/- 6.3 pg/mL) compared to children with an AHI < 5/h (mild SDB; 66.4 +/- 19.1 pg/mL; p < 0.01) and control subjects (27.8 +/- 3.7 pg/mL; p < 0.01). Similarly, cys-LT (LTC4/LTD4/LTE4) concentrations were also increased in SDB (45.1 +/- 10.6 pg/mL in SDB vs 27.6 +/- 8.3 pg/mL in mild SDB, and 15.7 +/- 7.6 pg/mL in control subjects; p < 0.01). In contrast, PGE2 concentrations were similar among the three groups. CONCLUSIONS: Inflammatory mediators such as leukotrienes and prostaglandins can be readily quantified in EBC collected from the upper airway of children. Disease severity-dependent increases in leukotriene concentrations (LTB4 and LTC4/LTD4/LTE4) emerge among children and may serve as a noninvasive tool in the clinical assessment of these children.     

Markers of airway inflammation in primary ciliary dyskinesia studied using exhaled breath condensate

Macroscopically, the airways in primary ciliary dyskinesia (PCD) are inflamed and infected, and the eventual result is bronchiectasis. The measurement of noninvasive markers of inflammation in PCD may allow determination of mechanisms of tissue damage, and even allow monitoring of therapy. The aim of this study was to measure in exhaled breath condensate (EBC) of children with PCD the concentrations of the neutrophil chemoattractants leukotriene (LT) B4 and interleukin (IL)-8 and the marker of oxidative stress 8-isoprostane (8-IP), and to try determining whether these markers can be used to assess mechanisms of airway inflammation in these patients. Concentrations of LTB4, IL-8, and 8-IP in the EBC of 23 PCD and 11 age-matched healthy children were measured using an enzyme immunoassay (EIA). The children also performed spirometry and underwent sputum induction, the latter for differential cell count. The concentrations of 8-IP in EBC of children with stable PCD were significantly increased compared to normal controls (median, 7.8 pg/ml vs. 3.1 pg/ml; P = 0.004). There was no difference in the median concentrations of EBC LTB4 between PCD subjects and healthy controls (28 pg/ml vs. 28 pg/ml; P = 0.5). IL-8 levels were below the detection limit of the assay, and were not analyzed further. There was no correlation between concentrations of either 8-IP or LTB(4) in EBC and forced expired volume in 1 sec in PCD children. Sputum induction was successful in 83% of the subjects; the median induced sputum neutrophil count was 69% (interquartile range, 59.3-73.6). No significant correlation was found between sputum neutrophils and either EBC 8-IP or LTB4 concentrations in PCD children. This study showed that oxidative stress, as reflected by increased exhaled 8-IP concentration, is increased in PCD children. The mechanism of airway neutrophilia is unclear, but is unlikely to be related to increased production of LTB4, at least in stable PCD patients.     

Relation between biomarkers in exhaled breath condensate and internal exposure to metals from gas metal arc welding

Concerning possible harmful components of welding fumes, besides gases and quantitative aspects of the respirable welding fumes, particle-inherent metal toxicity has to be considered.The objective of this study was to investigate the effect markers leukotriene B4 (LTB4),prostaglandin E2 (PGE2) and 8-isoprostane (8-Iso PGF2α) as well as the acid–base balance(pH) in exhaled breath condensate (EBC) of 43 full-time gas metal arc welders (20 smokers) in relation to welding fume exposure. We observed different patterns of iron, chromium and nickel in respirable welding fumes and EBC. Welders with undetectable chromium in EBC(group A, n = 24) presented high iron and nickel concentrations. In this group, higher 8-isoPGF2α and LTB4 concentrations could be revealed compared to welders with detectable chromium and low levels of both iron and nickel in EBC (group B): 8-iso PGF2α443.3 pg mL?1 versus 247.2 pg mL?1; p = 0.001 and LTB4 30.5 pg mL?1 versus 17.3 pgmL?1; p = 0.016. EBC-pH was more acid in samples of group B (6.52 versus 6.82; p = 0.011).Overall, effect markers in welders were associated with iron concentrations in EBC according to smoking habits--non-smokers/smokers: LTB4 (rs = 0.48; p = 0.02/rs = 0.21; p = 0.37),PGE2 (rs = 0.15; p = 0.59/rs = 0.47; p = 0.07), 8-iso PGF2α (rs = 0.18; p = 0.54/rs = 0.59;p = 0.06). Sampling of EBC in occupational research provides a matrix for the simultaneous monitoring of metal exposure and effects on target level. Our results suggest irritative effects in the airways of healthy welders. Further studies are necessary to assess whether these individual results might be used to identify welders at elevated risk for developing a respiratory disease.     

Cyclooxygenase- and lipoxygenase-derived eicosanoids in bronchoalveolar lavage fluid from patients with scleroderma lung disease: an imbalance between proinflammatory and antiinflammatory lipid mediators

OBJECTIVE: Eicosanoids play a key role in the regulation of inflammation and fibrosis. Recently we showed that levels of 5-lipoxygenase (5-LOX)-derived proinflammatory/profibrotic leukotrienes are elevated in bronchoalveolar lavage (BAL) fluid from patients with scleroderma lung disease (SLD). The present study was undertaken to investigate whether increased levels of leukotrienes are balanced by the antiinflammatory/antifibrotic cyclooxygenase (COX)- and 15-LOX-derived eicosanoids in the lungs of patients with SLD. METHODS: Levels of 5-LOX-derived leukotriene B(4) (LTB(4)), COX-derived prostaglandin E(2) (PGE(2)), and 15-LOX-derived 15-hydroxyeicosatetraenoic acid (15-HETE) and lipoxin A(4) (LXA(4)) in BAL fluid from systemic sclerosis (SSc) patients with SLD (n = 32) and without SLD (n = 16) and from healthy individuals (n = 12) were measured by enzyme-linked immunosorbent assay. RESULTS: Levels of LTB(4) (mean +/- SEM 248 +/- 29 pg/ml) and PGE(2) (51 +/- 10 pg/ml) in SSc patients with SLD were significantly higher compared with patients without SLD (LTB(4) 119 +/- 35 pg/ml, PGE(2) 17 +/- 3 pg/ml; P < 0.05 for both) and with healthy controls (85 +/- 12 pg/ml and 19 +/- 2 pg/ml, respectively; P < 0.05 for both). Accordingly, the mean +/- SEM PGE(2):LTB(4) ratio was similar in SSc patients with SLD (0.30 +/- 0.05), SSc patients without SLD (0.29 +/- 0.07), and controls (0.31 +/- 0.07). In contrast, levels of 15-HETE and LXA(4) in patients with SLD did not differ significantly from levels in patients without SLD or in controls. The ratio of LXA(4):LTB(4) in SLD patients (0.16 +/- 0.03) was significantly lower (P < 0.05) than that in patients without SLD (0.40 +/- 0.10) or controls (0.34 +/- 0.08). CONCLUSION: Increased production of LTB(4) in the lungs of patients with SLD is not balanced by an up-regulation of 15-LOX-derived antiinflammatory/antifibrotic eicosanoids such as 15-HETE or LXA(4). Targeting the 5-LOX/15-LOX balance may be of practical value in the treatment of SLD.     

Increased exhaled cysteinyl-leukotrienes and 8-isoprostane in aspirin-induced asthma

The pathogenesis of aspirin-induced asthma (AIA) has not yet been clearly elucidated, although eicosanoid metabolites appear to play an important role. We hypothesized that levels of eicosanoids in exhaled air condensate are abnormal in patients with AIA and that they change in patients receiving steroid therapy. We measured cysteinyl-leukotrienes (cys-LTs), prostaglandin E(2) (PGE(2)), and leukotriene B(4) (LTB(4)), and also 8-isoprostane as a marker of oxidative stress, by enzyme immunoassay in exhaled breath condensate from patients with AIA (17 steroid naive; mean age, 41 +/- 23 years; FEV(1), 63%pred), 26 patients with aspirin-tolerant asthma (ATA) (11 steroid naive; mean age, 47 +/- 18 years; FEV(1), 69%pred), and 16 healthy subjects (mean age, 45 +/- 17 years; FEV(1), 93%pred). Cys-LTs were significantly higher in steroid-naive patients with AIA compared with steroid-naive patients with ATA and healthy subjects (152.3 +/- 30.4 and 36.6 +/- 7.1 versus 19.4 +/- 2.8 pg/ml; p < 0.05 and p < 0.05, respectively). Steroid-naive patients with AIA also had higher levels of 8-isoprostane than normal subjects (131.8 +/- 31.0 versus 21.9 +/- 4.5 pg/ml; p < 0.05). There were significantly lower levels of both cys-LTs and 8-isoprostanes in steroid-treated patients with AIA. There was no difference in either the PGE(2) or LTB(4) level between the patient groups. This is the first study to show that cys-LTs and 8-isoprostanes are elevated in expired breath condensate of steroid-naive patients with AIA, and that cys-LTs are decreased in steroid-treated patients. Exhaled PGE(2) levels are not reduced, so that it is unlikely that a deficiency of PGE(2) is an important mechanism, whereas exhaled LTB(4) levels are unchanged, indicating an abnormality beyond 5-lipoxygenase.     

Increased macrophage inflammatory protein-1alpha and -1beta in BAL fluid of bronchiolitis obliterans organizing pneumonia

OBJECTIVE: CC chemokines are mainly chemotactic for monocytes and lymphocytes. The aim of this study was to evaluate the involvement of the CC chemokines, macrophage inflammatory protein (MIP)-1alpha and MIP-1beta, in the pathogenesis of bronchiolitis obliterans organizing pneumonia (BOOP). METHODOLOGY: The concentrations of MIP-1alpha and MIP-1beta in BAL fluid (BALF) obtained from patients with BOOP (n = 13) and control patients (CP, n= 18) were measured by enzyme-linked immunosorbent assay. RESULTS: MIP-1alpha in BALF was significantly higher in patients with BOOP (mean +/- SD; 123.8 +/- 98.0 pg/mL) than in CP (62.5 +/- 46.1 pg/mL). Significantly higher MIP-1beta was also detected in patients with BOOP (51.6 +/- 72.5 pg/mL) than in CP (6.4 +/- 3.7 pg/mL). The concentration of MIP-1alpha significantly correlated with the percentage of lymphocytes in BALF, and the concentration of MIP-1beta significantly correlated with the numbers of lymphocytes, neutrophils and eosinophils in BALF. Both MIP-1alpha and MIP-1beta in BALF were decreased after corticosteroid therapy and this was accompanied by decreased lymphocytes in BALF. CONCLUSION: This study suggests that MIP-1alpha and MIP-1beta may play important roles in the recruitment of immuno-inflammatory cells into the lungs, and may contribute to the pathogenesis of BOOP.     

Vascular endothelial growth factor in human lung transplantation

STUDY OBJECTIVES: To determine levels of the vascular endothelial growth factor (VEGF) isoform consisting of 165 amino acids (VEGF(165)) in BAL fluid (BALF) from lung transplant recipients (LTXs). DESIGN: Bronchoscopy with BAL was performed on LTXs and normal volunteers (NVs). SETTING: University hospital. PARTICIPANTS: LTXs (n = 57) and NVs (n = 15). MEASUREMENTS AND RESULT: VEGF(165) concentrations in BALF were higher (mean +/- SEM, 240 +/- 32 pg/mL) for NVs (n = 15) vs 133 +/- 14 pg/mL for LTXs (n = 37) who were stable without evidence of significant rejection or infection at 6 months after transplantation (p < 0.0001). BALF VEGF concentrations sampled at 24 to 48 h, 2 weeks, 4 weeks, and 6 months after transplantation for 11 LTXs who lacked rejection or infection at any time point were 71 +/- 8 pg/mL, 80 +/- 20 pg/mL, 82 +/- 13 pg/mL, and 167 +/- 31 pg/mL, respectively. VEGF concentrations in BALF for LTXs with cytomegalovirus (CMV) pneumonia were 55 +/- 12 pg/mL (n = 10), 117 +/- 33 pg/mL for grade A3 acute rejection (n = 9), and 82 +/- 17 pg/mL (n = 14) for active bronchiolitis obliterans syndrome (BOS). Concentrations of VEGF in BALF at 6 months for the 32 stable recipients with bilateral lung transplantation were significantly higher for those with higher values for FEV(1), and BALF VEGF concentrations were significantly lower in BALF at 6 months for those recipients who subsequently went on to develop BOS (86 +/- 19 pg/mL) vs those who did not (158 +/- 18 pg/mL; p = 0.03). Serum concentrations of VEGF did not correlate with VEGF concentrations in BALF, but serum VEGF was 291 +/- 62 pg/mL at 10 to 14 days after transplantation vs 130 +/- 20 pg/mL at 4 weeks for nine LTXs with paired samples (p < 0.02). Serum VEGF concentrations for NVs (n = 15) were 102 +/- 15 pg/mL vs 94 +/- 17 for stable LTXs (n = 12) at 24 weeks after transplantation and 123 +/- 33 pg/mL for LTXs with active BOS (n = 10). CONCLUSIONS: BALF VEGF concentrations are particularly depressed at early time points following lung transplantation, gradually improve in the absence of significant rejection or infection, and are lower with active rejection or CMV pneumonia.     

Use of segmental airway lavage to obtain relevant mediators from the lungs of asthmatic and control subjects

Studies have demonstrated that increased amounts of histamine in the airways of asthmatic patients are associated with increased airway reactivity. However, using routine bronchoalveolar lavage (BAL), histamine can be detected in only a portion of asthmatic subjects and a minority of control populations. To obtain relevant mediators from the airways in higher concentrations by avoiding the dilution inherent with a standard BAL, a technique was developed to lavage isolated airway segments of the human lung that employed a double-lumen bronchoscope and a balloon-tipped catheter. Lavage fluid obtained by this method yielded significantly higher concentrations of histamine than that obtained with routine BAL (asthmatic subjects, 2,403 +/- 633 pg/ml vs 188 +/- 42 pg/ml; rhinitis subjects, 533 +/- 187 pg/ml vs 113 +/- 53 pg/ml; normal subjects, 174 +/- 63 pg/ml vs 11 +/- 11 pg/ml). Similar findings were also noted for prostaglandin D2 (PGD2). Segmental airway lavage also resulted in higher lavage fluid concentrations of LTB, than routine BAL. Segmental airway lavage should help in studying the relationship of mast cell degranulation to airways reactivity in both asthmatic and other study populations.     

Quantitative analysis of 8-isoprostane and hydrogen peroxide in exhaled breath condensate.

Exhaled breath condensate (EBC) provides a noninvasive means of sampling the lower respiratory tract. Collection of EBC might be useful in the assessment of airway oxidative stress in smokers. The aim of this study was to determine 8-isoprostane and hydrogen peroxide levels in EBC, and, in addition, to investigate the reproducibility of these measurements. EBC samples were collected from 12 healthy male smokers at three time points within 1 week. 8-isoprostane and H2O2 were measured in nonconcentrated EBC using immunochemical and colorimetric assays, respectively. 8-isoprostane and H2O2 were detected in only 36 and 47% of all EBC samples, respectively. It was not possible to calculate the within-subject variation in a reliable manner since only three of the 12 smokers exhibited detectable 8-isoprostane concentrations on all three occasions (mean 4.6 pg x mL(-1); range 3.9-7.7 pg x mL(-1)), whereas H2O2 could not be detected on all three occasions in any of the smokers. Spiking experiments revealed a recovery of 83.5-109.5% for 8-isoprostane and 69.9-129.0%, for H2O2 in fresh EBC samples. It was concluded that levels of 8-isoprostane and hydrogen peroxide cannot be reproducibly assessed in exhaled breath condensate from healthy smokers because of their low concentration and/or the lack of sensitivity of the available assays.     

Inflammatory response to sputum induction measured by exhaled markers

BACKGROUND: Sputum induction is increasingly used to study both cellular and biochemical composition of the airways. However, there is a significant rise in the percentage of neutrophils at 8 h after inhalation with hypertonic saline. OBJECTIVE: The aim of this study was to assess whether markers of inflammation in exhaled air and exhaled air condensate change after sputum induction in normal and asthmatic subjects. METHODS: We measured leukotriene B(4) (LTB(4)) and a marker of oxidative stress, 8-isoprostane, (by enzyme immunoassay) in exhaled air condensate and exhaled nitric oxide (NO; by chemiluminescence analyzer) in 15 healthy subjects (8 females, mean age 35 +/- 4 years, FEV(1) 97.4% predicted) and in 8 mild asthmatic subjects (5 males, mean age 34 +/- 2 years, FEV(1) 70.5% predicted). RESULTS: LTB(4) was significantly higher compared with baseline at 6 h but did not remain increased at 24 h after sputum induction (134.3 +/- 30.15 and 75.4 +/- 14.32 vs. 64.6 +/- 11.6 pg/ml at baseline; p < 0.02 and p > 0.05, respectively) in healthy subjects. An inverse correlation between LTB(4) and exhaled NO at 6 h after sputum induction was observed in healthy subjects (r = -0.66, p < 0.03). No increase in LTB(4) levels was observed in asthmatic patients. Baseline 8-isoprostane levels were higher in asthmatic patients than in healthy subjects (47.3 +/- 37.1 vs. 17.5 +/- 8.8 pg/ml; p < 0.01). A trend towards increased levels of 8-isoprostane could be observed at 6 and 24 h after inhalation in healthy subjects (26.2 +/- 3.7 and 26.7 +/- 3.9 pg/ml; p = 0.09 and p = 0.07, respectively). In healthy subjects, exhaled NO was significantly higher compared with baseline at 6 h and remained increased 24 h after sputum induction (7.96 +/- 3.5 vs. 5.61 +/- 1.86 ppb; p < 0.01 and p < 0.05, respectively). Exhaled NO levels were increased in asthmatic patients but did not further increase after sputum induction. CONCLUSIONS: Sputum induction with hypertonic saline causes an inflammatory response which should be considered when using the technique to monitor airway inflammation.     

Elevated levels of leukotriene B4 and leukotriene E4 in bronchoalveolar lavage fluid from patients with scleroderma lung disease

OBJECTIVE: The leukotrienes are a family of arachidonic acid-derived lipid mediators with proinflammatory and profibrotic properties. The aim of this study was to analyze the role of leukotriene B(4) (LTB(4)) and LTE(4) in the pathogenesis of scleroderma lung disease (SLD). METHODS: Nineteen systemic sclerosis (SSc) patients with SLD, 11 SSc patients without SLD, and 10 healthy controls were studied. Bronchoalveolar lavage (BAL) fluid was obtained during routine bronchoscopy of the right middle lobe in all study subjects. Levels of LTB(4) and LTE(4) were measured using enzyme immunoassay kits. RESULTS: Levels of LTB(4) and LTE(4) were significantly higher in SSc patients with SLD (251 +/- 170 pg/ml and 479 +/- 301 pg/ml, respectively), than those in patients without SLD (114 +/- 86 and 159 +/- 149 pg/ml) and those in normal controls (86 +/- 49 and 110 +/- 67 pg/ml). In the total group of patients with SSc, levels of both leukotrienes correlated positively with the total number of cells in the BAL fluid and correlated negatively with the forced vital capacity. After intravenous pulse therapy with cyclophosphamide in 6 patients, there was a significant reduction in the concentration of LTB(4) (from 380 +/- 196 pg/ml to 155 +/- 123 pg/ml) but no significant difference in the levels of LTE(4) (from 697 +/- 325 pg/ml to 418 +/- 140 pg/ml). CONCLUSION: Our findings show that LTB(4) and LTE(4) levels are elevated in SSc patients with SLD and correlate with parameters of inflammation in the lungs. These results indicate that leukotrienes may contribute to the pathogenesis of SLD and may represent a new therapeutic target.     

Evaluation of CD30 as a marker for th2 lymphocytes in bronchoalveolar lavage in interstitial lung diseases

Several studies have been carried out to clarify the relationship between CD30 expression and Th2 lymphocytes, although the results have been controversial. To investigate whether CD30 is a useful marker for Th2 lymphocytes in bronchoalveolar lavage (BAL) in interstitial lung diseases (ILD), we studied six control subjects and 31 patients with ILD (12 with idiopathic pulmonary fibrosis, seven with hypersensitivity pneumonitis, three with chronic eosinophilic pneumonia and nine with sarcoidosis). The levels of interleukin-5 (IL-5) (secreted by Th2 cells), interferon-gamma (IFNgamma) (secreted by Th1 cells) and the expression of CD30 on lymphocytes were determined in BAL fluid. There were no differences in the percentage of CD30+ lymphocytes between controls and patients with ILD (0.8+0.4% vs. 2+/-0.4%). In order to determine the relationship between Th2 cells and CD30 expression, we divided the patients into two groups according to BAL IL-5 levels. Group I consisted of eight patients (three chronic eosinophilic pneumonia, three hypersensitivity pneumonitis, two idiopathic pulmonary fibrosis) with high IL-5 levels (298+/-138 pg ml(-1)). Group II consisted of the remaining 23 ILD patients with normal IL-5 levels (0.9+/-0.6 pg ml(-1)). The percentage of eosinophils in BAL fluid was significantly higher in group I compared with group 11 (34+/-16% vs. 3+/-1%, P < 0.05). A correlation between CD30+ lymphocytes and IL-5 in group 1 was not shown. There were no differences in the number of CD30+ I we found a significant correlation between IL-5 levels and the percentage of eosinophils (r = 0.95, P < 0.0001). Our results suggest that CD30 does not appear to be a useful marker for Th2 lymphocytes in BAL from patients with ILD.     

Increased exhaled 8-isoprostane in childhood asthma

STUDY OBJECTIVE: To quantify lung oxidative stress in asthmatic children by measuring concentrations of 8-isoprostane, a marker of oxidative stress, in exhaled breath condensate (EBC), which is a noninvasive method of sampling airway secretions. Secondary objectives were as follows: (1) to measure levels of exhaled prostaglandin (PG) E(2), since impaired PGE(2) production has been implicated in the pathogenesis of asthma in adults; and (2) to measure levels of fractional exhaled nitric oxide (FeNO), which is a marker of airway inflammation. DESIGN: Single-center, cross-sectional study. PATIENTS: Twelve healthy children, 12 steroid-na?ve asthmatic children, and 30 children in stable condition with mild-to-moderate persistent asthma who were being treated with inhaled corticosteroids (ICSs) [average dose, 300 micro g per day] were studied. INTERVENTIONS: Subjects attended the outpatient clinic on one occasion for the collection of EBC and FeNO measurements. Measurements and results: 8-Isoprostane and PGE(2) concentrations in EBC were measured with specific radioimmunoassays. FeNO was measured online by a chemiluminescence analyzer. 8-Isoprostane was detectable in the EBC of healthy children (mean [+/- SEM], 34.2 +/- 4.5 pg/mL), and its concentrations were increased in both steroid-na?ve asthmatic children (mean, 56.4 +/- 7.7 pg/mL; p < 0.01) and steroid-treated asthmatic children (mean, 47.2 +/- 2.3 pg/mL; p < 0.05). There was no difference in exhaled 8-isoprostane concentrations between the two groups of asthmatic children (p = 0.14). By contrast, exhaled PGE(2) concentrations were similar among the three study groups (p = 0.56). FeNO levels were higher in steroid-na?ve children with asthma (49.2 +/- 9.6 parts per billion [ppb]; p < 0.05) and, to a lesser extent, in steroid-treated asthmatic children (37.8 +/- 6.6 ppb; p < 0.05) compared with healthy children (15.2 +/- 1.7 ppb). CONCLUSIONS: Lung oxidative stress is increased in children who are in stable condition with asthma, as reflected by increased exhaled 8-isoprostane concentrations. This increase seems to be relatively resistant to treatment with ICSs. Decreased PGE(2) lung production is unlikely to play a pathophysiologic role in childhood asthma.     

The relationship between oxidative stress and acid stress in adult patients with mild asthma

BACKGROUND: Oxidative stress plays an important role in the pathogenesis of asthma. Interestingly, a low airway pH and a high concentration of 8-isoprostane, a marker of oxidative stress, has been reported to cause inflammatory airway diseases. However, the relationship between these 2 markers and pulmonary function has not been determined in mild asthma patients. METHODS: pH and 8-isoprostane concentration were measured in exhaled breath condensate (EBC) from patients with mild asthma (n = 44) and healthy subjects (n = 20). The relationship between acid stress (pH) and oxidative stress (8-isoprostane) was then analyzed, along with the relationships between these 2 markers and lung function. RESULTS: The median (interquartile range [IQR]) pH of EBC was significantly lower in asthma patients than in control subjects (7.53 [7.41-7.68] vs 7.70 [7.62-7.74], P < .05), while the median (IQR) 8-isoprostane concentration of EBC was significantly higher in asthma patients than control subjects (16.2 [11.7-19.1] vs 3.5 [2.6-7.9] pg/mL, P < .05). There was no correlation between pH and 8-isoprostane concentration. Furthermore, lung function was not correlated with either pH or 8-isoprostane concentrations in EBC. CONCLUSIONS: Acid stress and oxidative stress assessed by pH and 8-isoprostane concentration, respectively, in EBC did not show parallel changes associated with asthma and were not correlated with lung function in asthma patients. These 2 stress factors may have different roles in the pathogenesis of asthma.     

Alveolar macrophages from patients with asbestos exposure release increased levels of leukotriene B4

The alveolar influx and subsequent activation of inflammatory cells such as neutrophils and eosinophils are believed to be important in the pathogenesis of many interstitial lung disorders, including asbestosis. Indices of lower respiratory tract abnormalities detected by bronchoalveolar lavage (BAL) were investigated in 93 asbestos-exposed workers as well as in smoking (n = 12) and nonsmoking (n = 10) control subjects. Patients with clinical asbestosis (n = 12) exhibited increases in both BAL neutrophils and BAL eosinophils, expressed as both percentage of total cells and total numbers, when compared to asbestos-exposed workers without asbestosis (n = 81) and control subjects. Significantly greater numbers of BAL neutrophils were also found in asbestos-exposed workers without asbestosis than in either smoking or nonsmoking control subjects. These abnormalities correlated significantly with in vitro BAL alveolar macrophage production of the potent leukocyte chemotaxin, leukotriene B4 (LTB4). For example, basal, unstimulated LTB4 production was 3.1 +/- 0.8 ng/10(6) alveolar macrophages for patients with asbestosis, 1.05 +/- 0.2 ng/10(6) cells in asbestos workers without asbestosis, 0.9 +/- 0.2 ng/10(6) cells in control nonsmokers, and 0.2 +/- 0.05 ng/10(6) cells in control smokers. Stimulated LTB4 release from BAL alveolar macrophages (A23187 or arachidonate) was even more pronounced in asbestos workers with or without asbestosis, suggesting an in vivo priming effect on alveolar macrophage synthesis of LTB4. Cell-free BAL supernatants from asbestos-exposed patients with or without asbestosis also contained significantly greater amounts of LTB4 than did those from control subjects, indicating enhanced in vivo production of this inflammatory mediator.(ABSTRACT TRUNCATED AT 250 WORDS)     

Variability of exhaled breath condensate leukotriene B4 and 8-isoprostane in COPD patients

The reproducibility of exhaled breath condensate (EBC) mediators is not well documented in chronic obstructive pulmonary disease (COPD). This study assessed within assay (WA), within (WD) and between day (BD) reproducibility of EBC leukotriene B₄ (LTB₄) and 8-isoprostane. Three EBC samples were collected from 24 COPD patients separated by 1 h and 1 wk, to assess WD and BD reproducibility. WA reproducibility was assessed by sample analysis by enzyme immunoassay in triplicate. WA coefficient of variation for LTB₄ and 8-isoprostane (18.2% and 29.2%, respectively) was lower than corresponding values for WD (47.7% and 65.3%, respectively) and BD (75.7% and 79.1%, respectively). Repeatability coefficient for 8-isoprostane and LTB₄ assays were 18.6 pg/ml and 13.2 pg/ml, respectively. Group mean differences for WD and BD were small and statistically nonsignificant. Using the Bland Altman method, there were wide limits of agreement for WD (−51.6 to 47.2 for 8-isoprostane and −31.8 to 31.4 for LTB₄) and BD reproducibility (−61.4 to 75.7 for 8-isoprostane and −29.3 to 38.6 for LTB₄). This is the first study to fully report the variability of EBC 8-isoprostane and LTB₄ in COPD. WA variability and group mean changes were small. However, we observed considerable WD and BD variability for these biomarkers.     

Diagnostic role of BAL fluid CD4/CD8 ratio in different radiographic and clinical forms of pulmonary sarcoidosis

Introduction: Bronchoalveolar lavage (BAL) as a method of sampling cells is useful in the diagnosis and differential diagnosis of sarcoidosis. However, CD4/CD8 ratio in BAL fluid (BALF) is highly variable and it generates continuous discussions about its diagnostic role. Objective: To prospectively evaluate diagnostic role of BALF CD4/CD8 ratio in pulmonary sarcoidosis manifested in different radiographic and clinical forms in the real clinical practice. Material and methods: The study population consisted of 318 sarcoid patients with a newly diagnosed disease. Comparator groups consisted of 55 healthy subjects and 130 patients with other disorders who underwent BAL and examination of CD4/CD8 ratio in BALF as a step of diagnostic pathway. Diagnostic accuracy of CD4/CD8 ratio in BALF using receiver‐operating characteristic analysis has been calculated. Results: The percentage of BALF lymphocytes in sarcoid patients was significantly different from comparator groups. Normal BALF cell counts were found in 7% of sarcoid patients. However, typical sarcoid BALF cellular pattern was found in 6.2% of all control subjects. We have found that optimal cutoff points for CD4/CD8 ratio are 3.5 and 4.0 for asymptomatic and symptomatic patients, respectively. Sensitivity of the optimal cutoff points of CD4/CD8 ratio was lower in asymptomatic patients compared with symptomatic patients. Sensitivity of the optimal cutoff points decreased with the increased stage of sarcoidosis. Conclusions: BAL is a valuable method in diagnostic pathway of pulmonary sarcoidosis. However, results of BALF examination must be interpreted considering a specific clinical case. BALF CD4/CD8 ratio depends on clinical and radiographic manifestation. Please cite this paper as: Danila E, Norkūnien? J, Jurgauskien? L and Malickait? R. Diagnostic role of BAL fluid CD4/CD8 ratio in different radiographic and clinical forms of pulmonary sarcoidosis. The Clinical Respiratory Journal 2009; 3: 214–221.     

Increased leukotriene B4 and interleukin-6 in exhaled breath condensate in cystic fibrosis

Chronic neutrophilic airway inflammation is an important feature of cystic fibrosis (CF). Noninvasive inflammatory markers may be useful in monitoring CF. Leukotriene B4 (LTB4) and interleukin (IL)-6 are inflammatory mediators that are increased in chronic neutrophilic inflammation. The aim of this study was to assess whether LTB4 and IL-6 were increased in exhaled breath condensate of CF patients and whether they could be used to monitor inflammation. Twenty patients with CF (13 males, age of 28 +/- 9 years) were recruited together with 15 age-matched healthy subjects (8 males, age 35 +/- 7 years). LTB4 and IL-6 levels were markedly elevated in patients with acute exacerbations (28.8 +/- 4.3 and 8.7 +/- 0.4 pg/ml) compared with control subjects (6.8 +/- 0.7 and 2.6 +/- 0.1 pg/ml, p < 0.0001). We also observed a decrease of exhaled LTB4 and IL-6 concentrations after antibiotic treatment in six patients who were followed until clinically stable (31.1 +/- 4.4 and 9.5 +/- 0.4 pg/ml vs. 18.8 +/- 0.8 and 6.4 +/- 0.2 pg/ml, respectively) and an increase in 15 CF patients infected with Pseudomonas aeruginosa (34.3 +/- 5.0 and 9.3 +/- 0.3 pg/m) compared with those infected with other bacteria (18.3 +/- 0.7 and 6.9 +/- 0.5 pg/ml). These findings suggest that LTB4 and IL-6 levels are increased in exhaled breath condensate of patients with CF during exacerbation and could be used to monitor airway inflammation in these patients.     

Bronchoalveolar lavage fluid histamine levels in interstitial lung diseases

We measured bronchoalveolar lavage (BAL) fluid histamine in 36 normal subjects, 32 patients with sarcoidosis, and 28 patients with idiopathic pulmonary fibrosis (IPF). Patients with sarcoidosis and IPF had significantly greater BAL histamine (59 +/- 21 and 203 +/- 42 pg/ml, respectively) than did normal subjects (18 +/- 8 pg/ml). Sarcoidosis patients with Stage 3 chest radiographs had significantly greater BAL histamine than did sarcoidosis patients with radiographic Stages 0, 1, or 2. Sarcoidosis patients with higher BAL lymphocytes also had higher levels of BAL histamine. Furthermore, among the sarcoidosis patients, we found a marked interactive effect between higher BAL lymphocytes and Stage 3 radiographs on BAL histamine. In IPF, subjects with increased BAL lymphocytes had significantly less BAL histamine than subjects with normal levels of lymphocytes. These studies suggest that BAL histamine may be a useful marker (of more active disease and/or poorer prognosis) to be evaluated in prospective studies in patients with sarcoidosis and IPF.     

阻塞性睡眠呼吸暂停低通气综合征患者治疗前后呼出气冷凝液中8-异前列腺素水平的变化

目的探讨阻塞性睡眠呼吸暂停低通气综合征（OSAHS）患者治疗前后氧化应激标记物的变化以及这些变化与病情严重程度的关系。方法68例OSAHS患者中40例接受治疗2个月,其中33例使用持续气道正压通气治疗（CPAP）、5例行外科手术、2例使用口矫器,28例未经任何治疗,随访2个月。所有患者分别于治疗前和治疗后2个月,于晨起空腹时收集呼出气冷凝液（EBC）,同时抽取静脉血5ml,应用酶联免疫吸附法（ELISA）测定EBC和血清中8．异前列腺素的含量,并进行统计学的处理。结果治疗后EBC和血清中8-异前列腺素的水平较治疗前明显降低,差异具有显著性[EBC：（19．9±2．9）pg／ml,（14．4±3．1）pg/ml,P〈0．001;血清：（29．9±5．7）pg／ml,（20．4±3．9）pg／ml,P〈0．001];EBC和血清中8-异前列腺素水平的绝对变化（治疗后．治疗前）与呼吸暂停低通气指数（AHI）和最长窒息时间的绝对变化呈正相关（EBC：r=0．69,r=0．50,P〈0．001;血清：r=0．72,r=0．46,P〈0．001）,与夜间最低SaO2的绝对变化呈负相关（EBC：r=-0．58,P〈0．001;血清：r=-0．53,P〈0．001）。结论EBC和血清中8-异前列腺素的水平能通过治疗有效降低,治疗前后的水平变化与病情的严重程度有关,可作为随访病情和反映治疗效果的指标。