Birgitta Schmekel

Quantitative Assessment and Repeatability of Chlorine in Exhaled Breath Condensate

Background: Airway condition is presumably reflected in epithelial lining fluid (ELF). Exhaled breath condensate (EBC) has been used as a surrogate marker of the composition of ELF. Objectives: This study aimed at assessing the technical repeatability of chlorine measurements in EBC and comparing two separate condensators (Ecoscreen® and R Tube™) regarding recovery and repeatability. Furthermore, the association between condensate recoveries and variations in the airway status were scrutinized. Methods: EBC was collected using two condensators from 10 healthy volunteers. In addition, 13 asthmatic patients produced EBC with or without an added resistance of 5 cm H2O (Res5), applied to the outflow tract of Ecoscreen. All tests were done in random order. Chlorine levels (analyzed by a coulometric technique) in EBC served as a tool for investigation. Results: Chlorine was measurable in all samples. The coefficient of repeatability of chlorine measurements was <10%. Chlorine levels were higher in EBC obtained from R Tube (p < 0.001), and differences in recoveries and variability in chlorine levels were presumably related to technical differences in the condensators and not to the repeatability of chlorine measurements per se. Air-flow-dependent chlorine levels were obtained from healthy volunteers. Application of Res5, recruiting additional alveoli, resulted in increased recovery of the EBC volume, but not of chlorine, from those that had the most pronounced airway obstruction (p = 0.05). Conclusion: We conclude that by employing a sensitive analysis technique, chlorine is repeatedly measurable in EBC. We suggest that the bulk of chlorine in EBC originates from large airways and not from the alveolar area. Both condensators were comparable regarding repeatability but differed regarding chlorine recovery.

Analysis of breath samples for lung cancer survival

Analyses of exhaled air by means of electronic noses offer a large diagnostic potential. Such analyses are non-invasive; samples can also be easily obtained from severely ill patients and repeated within short intervals. Lung cancer is the most deadly malignant tumor worldwide, and monitoring of lung cancer progression is of great importance and may help to decide best therapy. In this report, twenty-two patients with diagnosed lung cancer and ten healthy volunteers were studied using breath samples collected several times at certain intervals and analysed by an electronic nose. The samples were divided into three sub-groups; group d for survivor less than one year, group s for survivor more than a year and group h for the healthy volunteers. Prediction models based on partial least square and artificial neural nets could not classify the collected groups d, s and h, but separated well group d from group h. Using artificial neural net, group d could be separated from group s. Excellent predictions and stable models of survival day for group d were obtained, both based on partial least square and artificial neural nets, with correlation coefficients 0.981 and 0.985, respectively. Finally, the importance of consecutive measurements was shown.

No effect of chinese acupuncture on isocapnic hyperventilation with cold air in asthmatics, measured with impulse oscillometry.

The cost to society and the individual of treating asthma has been increasing in developed countries. This has given rise to studies of the efficacy of complementary treatments. The aim of this study was to evaluate the efficacy of traditional Chinese Acupuncture in patients with mild asthma. The method used for evaluation of efficacy was total airway resistance at 5Hz (R5) as measured by impulse oscillometry (IOS) – a forced oscillation technique, at baseline and after a bronchial challenge with voluntary isocapnic hyperventilation of cold air (IHCA). The study was a parallel group randomised placebo controlled trial with evaluator blinding. Twenty-seven asthmatics were recruited and 24 completed the study, 10 of them received acupuncture and 14 received a placebo treatment (mock-TENS). Treatment continued for 15 weeks, and efficacy was tested two weeks following the last treatment. Randomisation resulted in female over representation in the acupuncture group, but lung-function and bronchial responsiveness to IHCA were comparable in the two populations before the start of treatment (p>0.05 vs. p>0.05). There were no statistically significant effects of the treatment before (p>0.05) or after IHCA (p>0.05) in either of the groups. The statistical power of the study to show a clinically relevant difference in bronchial responsiveness to IHCA after treatment was near 80%. We conclude that there were no significant effects of traditional Chinese Acupuncture on airway status in our patients with asthma.

High prevalence of emphysema and its association with BMI: A study of smokers with normal spirometry

Objectives. To evaluate to what extent emphysema was evident, as identified by High Resolution Computed Tomography (HRCT), in smokers with normal lung function and to relate age, gender, smoking history, and body mass index (BMI) to the HRCT results. A secondary aim was to study to what extent emphysema was present in smokers with lower normal values of lung function defined as FEV1/FVC ratio percentage of predicted value (89–93% of predicted value for males and 90–93% for females) or FEF50 ≤ 60% of predicted compared with smokers without this definition. Methods. Fifty-nine smokers, with a mean age of 53 years and with normal lung function, were examined with HRCT. Results. Emphysema evidenced visually by HRCT was present in 43% of the subjects. Using a 0–5 grade scale (0=normal finding; 5=emphysema in most slices), the degree of emphysema was almost exclusively 3–4. The type of emphysema was distributed as centrilobular emphysema predominant in 43.5%, paraseptal emphysema predominant in 43.5%, and as an equal mixture of these types in 13%. The presence of emphysema did not differ between the group of smokers with lower normal values of lung function and the rest of the smokers. Smokers with emphysema had significantly lower BMI than those devoid of emphysema, 24 and 27 respectively (p<0.0011). Conclusion. There was a high occurrence of visual emphysema in middle-aged smokers with normal lung function. The densitometric quantitative analysis method is inadequate for detecting mild emphysema. High prevalence of emphysema was associated with low BMI.

Efficacy of Two Breath Condensers

Background: Examination of Exhaled Breath Condensate has been suggested to give information about inflammatory airway diseases. Objectives: The aim was to compare efficacy and variability in gain of two commercially available exhaled breath condensers, ECoScreen® and RTube™ in an in vitro set up. Methods: Test fluids containing myeloperoxidase (MPO) or human neutrophil lipocalin (HNL) in addition to saline and bovine serum albumin were nebulized and aerosols were transferred by a servo ventilator to either of the two condensers. Analyses of MPO, HNL, or chlorine were done by means of ELISA, RIA, or a modified adsorbed organic halogen technique (AOX), respectively. Results: Recoveries of HNL were higher when using ECoScreen than RTube (P<0.05). In contrast, there were no significant differences between the two condensers in recoveries of MPO or chlorine. The spread of data was wide regarding all tested compounds. Conclusion: Variability in gain was large and ECoScreen was more efficacious then RTube in condensing the tested solutes of HNL, but not those of MPO or chlorine J. Clin. Lab. Anal. 24:219–223, 2010.

Chlorine in Breath Condensate – A Measure of Airway Affection in Pollinosis?

Background: Infiltration of inflammatory cells in bronchial mucosa and glandular hypersecretion are hallmarks of asthma. It has been postulated that exhaled breath condensate (EBC) mirrors events in epithelial lining fluid of airways, such as presence of local inflammation as well as glandular hypersecretion. It is also well known that eosinophil cationic protein (ECP) and cysteinyl-leukotrienes (cys-LT) are released by circulating inflammatory cells when triggered by antigen stimulation in asthma patients. Objectives: The aim of this study was to evaluate whether chlorine and/or cys-LT in EBC would reflect changes of exposure of airborne pollen in patients with asthma. Methods: EBC and serum were collected from 23 patients with allergic asthma during a pollen season and repeated 5 months later during a period with no aeroallergens. Chlorine was measured by means of a sensitive coulometric technique and cys-LT by an EIA technique. Serum ECP was measured and lung function tests were performed and symptoms noted during both occasions. Results: Significantly higher concentrations of chlorine in EBC (p = 0.007) and ECP in serum (p = 0.003) were found during the pollen season compared to post-season. Chlorine levels tended to be higher in patients who reported of chest symptoms compared to those who denied symptoms during the pollen season (p = 0.06). Areas under the receiver-operated characteristic curves (AUCROC) were compared and similar discriminative power to identify exacerbations of asthma was recorded by chlorine in EBC (range 0.67–0.78) and ECP in serum (range 0.64–0.78). Conclusion: It is concluded that chlorine in EBC and ECP in serum decreased significantly post-season, and this is suggested to mirror the decrement in airborne antigen. It is furthermore proposed that chlorine in EBC and ECP in serum tend to have a similar capacity to identify seasonal variations in airborne pollen in patients with asthma.

Decreased Serum Levels of P-Selectin and Eosinophil Cationic Protein in Patients with Mild Asthma after Inhaled Salbutamol

Background: Asthma is a chronic inflammatory disease of the airways associated with selective recruitment of activated eosinophils. P-selectin, a cell adhesion molecule, may be an important controller of the inflammation by mediating selective eosinophil cell influx to the lung. Serum levels of eosinophil cationic protein (ECP) have been used as a marker of eosinophil inflammation, and indirectly as a marker of disease activity of asthma. ECP levels may not be elevated in some patients with asthma, and this fact prompted us to search for additional surrogate markers for monitoring disease activity in asthma. Objectives: To evaluate whether repeated inhalations of salbutamol, a β-2-receptor agonist used for bronchodilation, would lead to reduced serum levels of P-selectin and/or ECP. Methods: Fourteen patients with asymptomatic mild stable asthma were enrolled into a randomised crossover study. Salbutamol was inhaled three times every 3 h. Blood was sampled 4 h after the last inhalation. Nine non-treated healthy volunteers served as control subjects. Serum ECP and P-selectin levels were measured using radioimmunoassay and ELISA, respectively. Results: P-selectin and ECP levels in serum obtained from asymptomatic asthmatics were close to those of the volunteers, and inter-day variability tended to be lower for levels of P-selectin than for ECP. Significant decreases of P-selectin (p = 0.01) and ECP (p = 0.03) were recorded after salbutamol inhalation. There was no association between the changes in ECP and P-selectin levels in serum. Conclusions: We conclude that decreases in P-selectin and ECP may have different kinetics, suggesting different pathways of action of salbutamol. We judge that P-selectin may be used as a sensitive marker in mild asthma.

Preserved bronchial dilatation after salbutamol does not guarantee protection against bronchial hyperresponsiveness.

Racemic salbutamol, a β2‐adrenoceptor agonist used for dilatation of airways, has recently been shown to induce lessened relaxation of bronchial smooth muscle and partial loss of bronchoprotection, seen as increased hyperresponsiveness, after regular treatment. The racemate undergoes stereo‐selective disposition, giving higher plasma levels of S‐salbutamol than that of bronchodilating R‐salbutamol, thus raising S : R ratios after repeated administration. Our aim was to evaluate whether increased bronchial hyperresponsiveness (BHR) could be found even after 1 day of repeated salbutamol inhalations, with β2‐receptor‐induced bronchial smooth muscle relaxation remaining and whether this would be associated with plasma levels of either enantiomer. Fifteen patients with stable asthma, aged 19–54 years, were included in a randomized, cross‐over study. An indirect bronchial challenge method was used [voluntary isocapnic hyperventilation of cold air (IHCA)], and airway condition tested by means of impulse oscillometry. Racemic salbutamol was inhaled three times during a 6‐h period. IHCA was performed and plasma concentrations of enantiomers were measured 4 h after the last dose. Tests were also performed without preceding drug treatment. β2‐Agonist‐produced bronchial dilatation and protection persisted in the majority of the 15 patients 4 h after repeated inhalations of salbutamol during 1 day. In only two of the 15 patients we could trace increased BHR after salbutamol. Neither dilatation nor protection could be linked to plasma levels of either R‐ or S‐salbutamol. The underlying mechanisms of BHR remain unknown and are dissociated from β2‐receptor‐mediated dilatation.

Serum lysozyme - a surrogate marker of pulmonary microvascular injury in smokers?

Progression rate of disease processes in smoke‐induced lung injuries varies greatly. Diverse pathophysiological mechanisms may trigger these divergences. The aim of this study was to evaluate whether circulating markers of monocytes/macrophages and/or neutrophil [i.e. lysozyme (LZM) or myeloperoxidase (MPO)] were associated with reduced values of diffusion capacity (DL,CO), which is considered to serve as a mirror of pulmonary microvascular derangement and an early sign of tissue remodelling in smokers. Data obtained from 134 smokers (GOLD stage ≤1) and 24 matched healthy non‐smoking volunteers were evaluated in a cross‐sectional study design. Lung function tests as well as single breath test of DL,CO were assessed according to ATS/ERS guidelines. Biomarkers were measured in serum by means of sensitive immunoassays. A subgroup of smokers with normal lung function was created to minimize confounding, by excluding datasets showing significant airflow limitation and abnormally high values of carboxy haemoglobin (COHb), the latter indicating recent smoking. The capacity of serum lysozyme to correctly identify abnormally low values of DL,CO (i.e. <1·9SD units), tended to be higher than that of Myeloperoxidase as assessed by analyses of receiver operated curves (ROC; AUC 0·81, 95%CI: 0·69–0·89 versus AUC 0·67, 95%CI: 0·60–0·81). It is concluded that serum levels of lysozyme, reflecting mainly activated monocytes/macrophages but also neutrophils, were significantly associated with isolated decrements of DL,CO in smokers with normal lung function tests. This suggests monocytes/macrophages to have a significant mechanistic role in early phases of the disease process and/or pulmonary microvascular damage.

Histamine release from blood cells and serum ECP in patients with asthma, during and after a mild pollen season.

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