Effects of low dose fluticasone/salmeterol combination on surrogate inflammatory markers in moderate persistent asthma

BACKGROUND: Noninvasive surrogate markers provide valuable information on the asthmatic inflammatory process. We wished to examine the effects of low dose fluticasone/salmeterol combination on different commonly used inflammatory markers in moderate persistent asthma. METHODS: Twenty-five moderate persistent atopic asthmatics were enrolled of whom 20 completed an open label study. Following an initial 4 week steroid washout period in which patients took salmeterol 50 microg dry powder inhaler 1 puff BD, they received the addition of fluticasone as fluticasone 100 microg/salmeterol 50 microg combination dry powder inhaler 1 puff BD for the next 2 weeks. Exhaled nitric oxide, spirometry, methacholine PD20, sputum/blood eosinophils and sputum/serum eosinophil cationic protein (ECP) were measured following the salmeterol only and fluticasone/salmeterol combination treatment periods. RESULTS: Compared to salmeterol alone (i.e. after the steroid washout), the use of fluticasone/salmeterol combination conferred significant improvements (P < 0.05) in all surrogate markers of inflammation apart from serum ECP. Geometric mean fold changes were 4.3-fold/1.3-fold for sputum/blood eosinophils, 2.2-fold/1.2-fold for sputum/serum ECP, 2.3-fold for methacholine PD20 and 1.8-fold for exhaled nitric oxide. CONCLUSIONS: Surrogate markers apart from serum ECP may be used as a guide to evaluate the anti-inflammatory effects of low dose inhaled corticosteroids. Sputum markers tend to be more sensitive than blood when assessing the anti-inflammatory response.     

Effects of inhaled corticosteroids on exhaled leukotrienes and prostanoids in asthmatic children

BACKGROUND: Lipid mediators play an important pathophysiologic role in atopic asthmatic children, but their role in the airways of atopic nonasthmatic children is unknown. OBJECTIVE: We sought (1) to measure leukotriene (LT) E 4 , LTB 4 , 8-isoprostane, prostaglandin E 2 , and thromboxane B 2 concentrations in exhaled breath condensate in atopic asthmatic and atopic nonasthmatic children; (2) to measure exhaled nitric oxide (NO) as an independent marker of airway inflammation; and (3) to study the effect of inhaled corticosteroids on exhaled eicosanoids. METHODS: Twenty healthy children, 20 atopic nonasthmatic children, 30 steroid-naive atopic asthmatic children, and 25 atopic asthmatic children receiving inhaled corticosteroids were included in a cross-sectional study. An open-label study with inhaled fluticasone (100 microg twice a day for 4 weeks) was undertaken in 14 steroid-naive atopic asthmatic children. RESULTS: Compared with control subjects, exhaled LTE 4 ( P <.001), LTB 4 ( P <.001), and 8-isoprostane ( P <.001) levels were increased in both steroid-naive and steroid-treated atopic asthmatic children but not in atopic nonasthmatic children (LTE 4 , P=.14; LTB 4 , P=.23; and 8-isoprostane, P=.52). Exhaled NO levels were increased in steroid-naive atopic asthmatic children ( P <.001) and, to a lesser extent, in atopic nonasthmatic children ( P <.01). Inhaled fluticasone reduced exhaled NO (53%, P <.0001) and, to a lesser extent, LTE 4 (18%, P <.01) levels but not LTB 4 , prostaglandin E 2 , or 8-isoprostane levels in steroid-naive asthmatic children. Conclusions Exhaled LTE 4 , LTB 4 , and 8-isoprostane levels are increased in atopic asthmatic children but not in atopic nonasthmatic children. In contrast to exhaled NO, these markers seem to be relatively resistant to inhaled corticosteroids.     

Eosinophilic bronchitis in asthma: a model for establishing dose-response and relative potency of inhaled corticosteroids

BACKGROUND: Newer generations and formulations of inhaled corticosteroids have necessitated the development of a clinically relevant model to compare their clinical potency. OBJECTIVE: We evaluated whether sputum eosinophil counts could demonstrate a dose-response to inhaled corticosteroids, and compared the response with other inflammatory markers. METHODS: Fourteen steroid-naive patients with asthma with an initial sputum eosinophilia of > or = 2.5% entered a 6-week sequential, placebo-controlled, patient-blinded, cumulative dose-response study. After 7 days of placebo, they received incremental doses of fluticasone propionate (FP), 50, 100, 200, and 400 microg/d, each for 7 days. Measurements were made of sputum and blood eosinophils, exhaled nitric oxide, spirometry, airway responsiveness to methacholine (methacholine PC20), and symptom scores before and after each dose. RESULTS: Sputum eosinophils and exhaled nitric oxide were extremely sensitive to the effects of FP, and exhibited significant dose-dependent reductions of 99.4% and 99.8 parts per billion, respectively, where each variable was expressed per 100 microg/d FP. This compared with a 0.5 doubling dose increase of airway responsiveness to methacholine and a 0.3 decrease in symptom scores. Airway responsiveness to methacholine was the only variable that increased throughout the study. CONCLUSION: These results suggest that the model of eosinophilic bronchitis could be used to compare the effect of cumulative doses of an inhaled corticosteroid delivered by different types of delivery systems or preparations using a relatively small number of patients. CLINICAL IMPLICATIONS: Future clinical studies based on this model will allow clinicians to make informed decisions regarding the relative potencies of different inhaled corticosteroids.     

Changes in serum eotaxin and eosinophil cationic protein levels, and eosinophil count during treatment of childhood asthma.

BACKGROUND AND PURPOSE: Increased serum levels of eotaxin are related to the severity of asthma in adults. There are limited data on the effects of oral corticosteroids and inhaled corticosteroid therapy on serum levels of eotaxin and eosinophil cationic protein (ECP) and peripheral blood eosinophil counts (ECs) in pediatric asthma patients. We investigated prospectively the changes in eotaxin and ECP serum levels and peripheral blood ECs after administering oral corticosteroids and then inhaled corticosteroids plus long-acting beta2 agonist treatment in pediatric patients. METHODS: Serum samples of 20 pediatric patients with mild-to-moderate asthma were collected before treatment, after 5-7 days of oral prednisolone treatment, and after 1-2 months of inhaled fluticasone plus salmeterol treatment. Peak expiratory flow was used as the outcome index. RESULTS: Serum eotaxin levels remained the same after oral prednisolone treatment, but decreased after subsequent inhalation treatment compared with the end of oral steroid treatment (64.7 +/- 22.6 vs 85.7 +/- 36.8 pg/mL, p<0.001). The EC and serum ECP levels declined soon after oral steroid treatment, rebounding to initial levels during inhalation treatment. The decrease in ECP level was positively correlated with the decrease in ECs with oral steroid treatment (r(2) = 0.28, p=0.016). There was no correlation between changes in eotaxin levels and peak expiratory flow. CONCLUSIONS: Our data suggest that the serum eotaxin level, not peripheral blood EC or serum ECP level, declines during inhaled fluticasone plus salmeterol treatment and might serve as a surrogate marker of T helper 2 residual activity in pediatric asthma.     

Bronchial responsiveness to leukotriene D4 is resistant to inhaled fluticasone propionate

BACKGROUND: Inhaled corticosteroids are highly effective in asthma, reducing inflammatory markers and bronchial hyperresponsiveness. Cysteinyl-leukotrienes are major mediators of airway obstruction and display proinflammatory effects. Although the synthesis of leukotrienes is not affected by corticosteroid treatment, the influence of corticosteroids on the leukotriene pathway remains unresolved. OBJECTIVE: We investigated whether or not bronchial responsiveness to leukotriene (LT) D(4) is reduced by fluticasone propionate in subjects with asthma. METHODS: In 13 subjects with mild asthma, inhalation challenges with methacholine and LTD(4) were performed on consecutive days before and after 2 weeks of treatment with inhaled fluticasone 500 mug, twice daily, in a double-blind, randomized, placebo-controlled study with crossover design and 3 weeks of washout between periods. Exhaled nitric oxide was measured as a marker of corticosteroid responsiveness, and baseline urinary LTE(4) concentrations as an index of cysteinyl-leukotriene biosynthesis. RESULTS: Fluticasone produced a significant decrease in methacholine responsiveness, corresponding to 2.6-fold shift in the PD(20) FEV(1), and a significant reduction in the levels of exhaled nitric oxide. By contrast, bronchial responsiveness to LTD(4) in the same subjects was unaffected by fluticasone, as were urinary LTE(4) concentrations. CONCLUSION: These new data indicate that neither the biosynthesis nor the actions of leukotrienes appear to be sensitive to inhaled corticosteroids. CLINICAL IMPLICATIONS: The study provides mechanistic support for the additive therapeutic efficacy of antileukotrienes and inhaled corticosteroids in asthma.     

Accuracy of eosinophils and eosinophil cationic protein to predict steroid improvement in asthma

BACKGROUND: There is a large variability in clinical response to corticosteroid treatment in patients with asthma. Several markers of inflammation like eosinophils and eosinophil cationic protein (ECP), as well as exhaled nitric oxide (NO), are good candidates to predict clinical response. AIM: We wanted to determine whether we could actually predict a favourable response to inhaled corticosteroids in individual patients. METHODS: One hundred and twenty patients with unstable asthma were treated with either prednisolone 30 mg/day, fluticasone propionate 1000 microg/day b.i.d. or fluticasone propionate 250 microg/day b.i.d., both via Diskhaler. They were treated during 2 weeks, in a double-blind, parallel group, double dummy design. We measured eosinophils and ECP in blood and sputum, and exhaled nitric oxide as inflammatory parameters before and after 2 weeks in order to predict the changes in forced expiratory volume in 1 s (FEV1), provocative concentration of methacholine causing a 20% fall in FEV1 (PC20 Mch), and asthma quality of life (QOL). Secondly, to test whether these results were applicable in clinical practice we determined the individual prediction of corticosteroid response. RESULTS: We found that changes in FEV1, PC20 Mch and QOL with corticosteroids were predominantly predicted by their respective baseline value and to a smaller extent by eosinophils in blood or sputum. ECP, measured in blood or sputum, was certainly not better than eosinophils in predicting clinical response to corticosteroids. Smoking status was an additional predictor for change in FEV1, but not for change in PC20 Mch or QOL. Prediction of a good clinical response was poor. For instance, high sputum eosinophils (> or = 3%) correctly predicted an improvement in PC20 Mch in only 65% of the patients. CONCLUSION: Our findings show that baseline values of the clinical parameters used as outcome parameters are the major predictors of clinical response to corticosteroids. Eosinophil percentage in blood or sputum adds to this, whereas ECP provides no additional information. Correct prediction of clinical response in an individual patient, however, remains poor with our currently used clinical and inflammatory parameters.     

Adding salmeterol to an inhaled corticosteroid reduces allergen-induced serum IL-5 and peripheral blood eosinophils

BACKGROUND: Adding a long-acting beta(2)-agonist to inhaled corticosteroids results in better symptomatic asthma control than increasing the dose of inhaled corticosteroids. OBJECTIVE: Investigating whether adding the long-acting beta(2)-agonist salmeterol to the inhaled corticosteroid fluticasone propionate has an effect on allergen-induced allergic inflammation in asthma. METHODS: Bronchial allergen challenges were performed in 26 patients with allergic asthma, pretreating them with a single dose of either fluticasone/salmeterol (100/50 microg) or fluticasone alone (100 microg), in a double-blind, randomized, cross-over design. Sputum and serum markers of bronchial inflammation were measured after allergen challenge, as well as lung function parameters. Primary outcomes were sputum eosinophil numbers and eosinophil cationic protein. RESULTS: Asthmatic responses after allergen challenge were significantly reduced after pretreatment with fluticasone/salmeterol relative to fluticasone alone. Sputum inflammatory markers after allergen challenge were not significantly affected by fluticasone/salmeterol pretreatment. By contrast, serum IL-5 was significantly reduced (geometric mean serum IL-5 [SEM]: 0.5 [0.3] vs 1.1 [0.3] pg/mL 1 hour and 0.6 [0.3] vs 1.1 [0.3] pg/mL 6 hours after challenge with fluticasone/salmeterol vs fluticasone alone pretreatment, respectively; P values < .05). Also, peripheral blood eosinophils were significantly reduced (geometric mean number x 10(6)/L [SEM]: 172 [0.1] vs 237 [0.1] at 6 hours and 271 [0.1] vs 351 [0.1] at 24 hours with fluticasone/salmeterol vs fluticasone alone pretreatment, respectively; P < .05). CONCLUSION: Adding salmeterol to fluticasone reduces allergen-induced serum IL-5 and peripheral blood eosinophils. This phenomenon may contribute to the improved clinical outcomes that result from adding a long-acting beta(2)-agonist to inhaled corticosteroids.     

Relationship between induced sputum cell counts and fluid-phase eosinophil cationic protein and clinical or physiologic profiles in mild asthma.

BACKGROUND: Sputum analysis is the only non-invasive method to examine airway inflammatory processes in subjects with asthma. The aim of this study was to investigate the relationship between cell counts and fluid phase levels in induced sputum in subjects with mild asthma, and the severity of asthma as assessed by clinical, physiologic and blood measurements. METHODS: Forty patients with mild asthma, aged 17 to 49 years were studied (good sputum sample only from 31). On the first day, spirometry and methacholine challenges were performed. After 2 to 4 days, venous blood for absolute eosinophil count and eosinophil cationic protein (ECP) measurement was obtained and sputum was induced by inhalation of hypertonic saline. For the next 15 days subjects recorded their peak expiratory flow (PEF), symptom scores, and beta2-agonist requirements twice daily. Differential counts of leukocytes were done on cytospin preparations of homogenized sputum and the supernatant was examined for eosinophil cationic protein (ECP). RESULTS: Sputum eosinophil counts and not neutrophil, epithelial cells, macrophages, or lymphocytes, were inversely correlated to FEV1/FVC % (r = -.57, P = .0008) and to PC20-methacholine (r = -.40, P = .024). No statistical relationship was obtained between eosinophil counts and either symptom scores, bronchodilator requirements, or daily PEF variability. Sputum ECP values were correlated to FEV1/FVC% (r = -.41, P = .026) but not to PC20 (r = -.32, P = .08) or clinical scores or PEF variation. A trend to significance was appreciated between peripheral blood and sputum eosinophil counts (r = .34, P = .067) and no relationship was found between sputum and serum ECP values (r = .10, P = .38). CONCLUSIONS: Although sputum markers give some information about disordered lung function and physiologic changes in the airways, they are not the only factors concerned in the clinical expression of mild asthma.     

Exhaled leukotrienes and prostaglandins in asthma

BACKGROUND: Most of the studies investigating the role of leukotrienes (LTs) and prostaglandins (PGs) in asthma have used invasive (eg, bronchoalveolar lavage fluid) or semi-invasive (eg, sputum induction) techniques. Others have measured eicosanoids in plasma or urine, probably reflecting systemic rather than lung inflammation. Collection of exhaled breath condensate (EBC) is a noninvasive method to collect airway secretions. OBJECTIVE: We sought to investigate whether eicosanoids are measurable in EBC, to show possible differences in their concentrations in asthmatic patients and healthy subjects, and to investigate whether exhaled eicosanoids correlate with exhaled nitric oxide (NO), a marker of airway inflammation. METHODS: Twelve healthy nonsmokers and 15 steroid-naive patients with mild asthma were studied. Subjects attended on one occasion for pulmonary function tests, collection of EBC, and exhaled NO measurements. Exhaled LTB(4)-like immunoreactivity, LTE(4)-like immunoreactivity, PGE(2)-like immunoreactivity, PGD(2)-methoxime, PGF(2)(alpha)-like immunoreactivity, and thromboxane B(2)-like immunoreactivity were measured by means of enzyme immunoassays. RESULTS: LTE(4)-like immunoreactivity and LTB(4)-like immunoreactivity were detectable in EBC in healthy subjects, and their levels in asthmatic patients were increased about 3-fold (P <.0001) and 2-fold (P <.0005), respectively. Exhaled NO was increased in asthmatic patients compared with healthy subjects (P <.0001). There was a correlation between exhaled LTB(4) and exhaled NO (r = 0.56, P <.04) in patients with asthma. When measurable, prostanoid levels were similar in asthmatic patients and control subjects. CONCLUSIONS: Exhaled LTE(4) and LTB(4) are increased in steroid-naive patients with mild asthma. EBC may be proved to be a novel method to monitor airway inflammation in asthma.     

Eosinophils and eosinophilic cationic protein in induced sputum and blood: effects of budesonide and terbutaline treatment.

BACKGROUND: There is a need for easily measurable markers of airway inflammation to guide the use of anti-inflammatory treatment in asthma. Eosinophilic cationic protein (ECP) levels in sputum and blood correlate with clinical severity, and serial measurements of ECP have been proposed as a suitable candidate. AIMS AND METHODS: Our aim was to confirm that sputum and serum ECP measurements would provide a more sensitive indicator of responses to asthma treatment than eosinophil counts per se, in a randomized, placebo-controlled, crossover study of terbutaline, budesonide, and their combination in patients with chronic persistent asthma. We compared the changes in eosinophil counts and ECP in induced sputum and blood during each treatment period. RESULTS: Budesonide and combined treatment caused a significant reduction in sputum eosinophils (-2.7% and -2.3%, respectively, P < 0.05). Sputum eosinophils increased with terbutaline (+3.9%, P = 0.049). In contrast, the changes for sputum ECP were not significant. There was a similar treatment effect on blood eosinophils, but not for serum ECP. Correlations between sputum and blood eosinophils were significant with and without budesonide, but were nonsignificant between sputum and blood ECP during the active treatments. Correlations between sputum eosinophils and ECP, and between blood eosinophils and serum ECP were greatest during treatment with placebo or terbutaline alone: budesonide weakened or abolished these relationships. CONCLUSIONS: Compared with eosinophil counts, ECP measurements in either induced sputum or serum failed to reflect treatment-related changes in chronic asthma. We conclude that ECP is not a sensitive or reliable means of evaluating airway inflammation, and can not be recommended for assessing responses to anti-inflammatory therapy.     

Airway neutrophil inflammation in nonasthmatic patients with food allergy

BACKGROUND: Patients with food allergy (FA) have been recently shown to develop bronchial hyperresponsiveness (BHR), despite the absence of any concomitant asthmatic manifestation. In order to explain this observation, we sought to examine the presence of a bronchial inflammation in induced sputum of nonasthmatic patients with FA. METHODS: Twelve nonasthmatic patients with FA (urticaria, digestive symptoms, anaphylaxis) were included in the study. Results were compared to these obtained from eight asthmatic patients without food allergy and eight healthy controls. Diagnosis of FA was based on double-blind placebo-controlled challenge. Sputum cells and fluid-phase eosinophil cationic protein (ECP), myeloperoxidase (MPO) and interleukin-8 (IL-8) were measured in induced sputum. BHR was evaluated using methacholine inhalation. RESULTS: Sputum from asthmatics, in comparison with the sputum of healthy subjects and patients with FA contained a higher proportion of eosinophils and higher levels of ECP (< 0.001). In marked contrast, patients with FA exhibited an increased proportion of neutrophils and IL-8 in comparison with asthmatics and controls (P < 0.05 for neutrophils and P < 0.001 for IL-8). There was a significant correlation between sputum neutrophils and IL-8 (r = 0.68, P < 0.001). MPO levels were not different between the groups. There was a trend toward higher levels of IL-8 and ECP in food allergic patients with BHR in comparison with patients with FA without BHR. CONCLUSION: Our results demonstrate that a subclinical neutrophil airway inflammation is present in patients with food allergy free of clinical respiratory symptoms and that IL-8 may be an important mediator of this neutrophilia.     

Effect of histamine and adenosine 5'-monophosphate provocation on sputum neutrophils and related mediators in atopic patients.

BACKGROUND: Airway hyperresponsiveness and inflammation can be noninvasively studied by bronchial provocation using direct (histamine) or indirect (adenosine 5'-monophosphate [AMP]) stimuli and induced sputum. OBJECTIVE: To report on the immediate effects of histamine and AMP challenge on induced sputum neutrophil counts and related mediator levels. METHODS: We performed a single-masked, randomized, placebo-controlled, 3-way, crossover, methodological study in 14 atopic patients (median age, 25 years; 8 males; mean +/- SD forced expiratory volume in 1 second, 99% +/- 5%) without anti-inflammatory medication use. At baseline, sputum induction was performed. Bronchial challenges with AMP, histamine, or placebo were performed 48 hours later. Thirty minutes after challenge, sputum induction was performed again. Challenge periods in each patient were separated by more than 2 weeks. Sputum cells and the mediators leukotriene B4, interleukin 8, myeloperoxidase, and albumin were quantified. RESULTS: Comparing median challenge-induced relative changes in cells and mediators, neither histamine nor AMP challenge altered the induced sputum neutrophil counts (histamine, 2.7%; AMP, 2.95%; placebo, -2%; P > .07 for all), interleukin 8 levels (histamine, 2.4 ng/mL; AMP, -3.8 ng/mL; placebo, -0.2 ng/mL; P > .06), leukotriene B4 levels (histamine, -4.8 pg/mL; AMP, 3 pg/mL; placebo, 6 pg/mL; P > .08), or myeloperoxidase levels (histamine, 0.16 microg/mL; AMP, 0 microg/mL; placebo, -0.03 microg/mL; P > .07). Sputum albumin levels were increased after histamine challenge compared with AMP and placebo challenge (P < .01 for both). CONCLUSIONS: Histamine and AMP provocation have no major effects on induced neutrophil counts and related mediator levels in atopic patients, whereas histamine challenge induces plasma leakage. Potential interactions of noninvasive methods to evaluate airway reactivity and inflammation should be carefully considered.     

Salbutamol pretreatment does not change eosinophil percentage and eosinophilic cationic protein concentration in hypertonic saline-induced sputum in asthmatic subjects

BACKGROUND: Sputum induction by inhalation of hypertonic saline (HS) is usually preceded by beta2-agonist pretreatment, to prevent severe bronchoconstriction. OBJECTIVE: To evaluate whether salbutamol pretreatment may influence cell counts and concentrations of soluble mediators in induced sputum. METHODS: We studied 22 patients who randomly underwent HS sputum induction after pretreatment with either 200 microg salbutamol or placebo. Sputum was induced by means of HS inhalation (3, 4, 5% NaCl, 10 min each), measuring FEV1 every 5 min until it fell >/= 20% from baseline. Collected sputum was diluted 1 : 1 with 0.1% DTT, incubated at 37 degrees C for 20 min, and total and differential cell counts were measured. ECP and histamine levels were measured in the supernatant. RESULTS: Sputum volume, percentages of inflammatory cells, squamous cell counts and quality of the slides were not different after the two pretreatments, while sputum total inflammatory cells after salbutamol tended to be higher than after placebo (8.3 [1-41] 10(6) vs 6.3[0.2-40] x10(6); P = 0.09). Eosinophilic cationic protein (ECP) did not significantly change (260 [8-900] microg/L after salbutamol vs 200 [8-800] microg/L, n = 19), while histamine levels tended to be lower after salbutamol (140.9 [39.9-236.5] nm) than after placebo (190.4 [72. 2-322.6] nm, P = 0.09, n = 17). The airway response to HS inhalation was significantly greater after placebo and the duration of the test was significantly different (median: 15 min after placebo and 30 min after salbutamol). Similar results were obtained when patients who differed for more than 15 min in the duration of HS-inhalation in the two tests were selected (n = 11). CONCLUSION: Salbutamol pretreatment reduces the severity of bronchoconstriction induced by HS inhalation without significantly affecting the percentages of inflammatory cells and the levels of soluble mediators in induced sputum.     

Relation between exhaled carbon monoxide levels and clinical severity of asthma

Carbon monoxide (CO) can be detected in exhaled air and is increased in asthmatic patients not treated with corticosteroids. However, it is uncertain whether exhaled CO is related to severity of asthma. To study whether exhaled CO is related to severity of asthma in clinical courses, exhaled CO concentrations were measured on a CO monitor by vital capacity manoeuvre in 20 mild asthmatics treated with inhaled beta2-agonists alone, 20 moderate asthmatics treated with inhaled corticosteroids, and 15 stable asthmatics treated with high dose inhaled corticosteroids and oral corticosteroids once a month over 1 years. Exhaled CO concentrations were also measured in 16 unstable severe asthmatics who visited the hospital every 7 or 14 days for treatment with high dose inhaled corticosteroids and oral corticosteroids. The mean values of exhaled CO in severe asthma over 1 year were 6.7 +/- 9.5 p.p.m. (n = 31, mean +/- SD) and significantly higher than those of non-smoking control subjects (1.2 +/- 0.9 p.p.m., n = 20, P < 0.01). Exhaled CO concentrations in unstable severe asthmatics were significantly higher than those in stable severe asthmatics. However, exhaled CO concentrations in mild and moderate asthmatics did not differ significantly from those in non-smoking control subjects (P > 0.20). There was a significant relationship between the exhaled CO concentrations and forced expiratory volume in one second in all asthmatic patients. These findings suggest that exhaled CO concentrations may relate to the severity of asthma and measurements of exhaled CO concentrations may be a useful means of monitoring airway inflammation in asthma.     

Sputum leukotrienes in obstructive airways diseases.

Sputum samples from patients with bronchial asthma, chronic bronchitis and cystic fibrosis were examined for the presence of leukotrienes B4, C4 and D4. Following ethanol extraction and purification on Amberlite XAD-8, leukotrienes were identified by high pressure liquid chromatography (HPLC) using the appropriate markers. Fractions from HLPC were also tested for biological activity using both the Boyden chemotaxis assay and FPL 55712 inhibitable contraction of the isolated guinea-pig ileum. LTB4 was detected in the HPLC fractionated sputa from bronchial asthma (seven of seven), chronic bronchitis (four of four) and cystic fibrosis (four of four). In contrast, bioassay on the guinea-pig ileum failed to detect LTC4 or LTD4 in 17 asthmatic sputa, although they were detected in one of five bronchitics and 16 of 25 patients with cystic fibrosis. The activity in eight of these cystic fibrosis sputa was further characterized by HPLC and shown to be LTC4 and/or LTD4. Sputum from 11 of 17 asthmatics, four of 25 patients with cystic fibrosis and two of five bronchitics contained an anaphylatoxin like substance. The majority of sputum samples containing LTB4 also possessed an activity with physical and biological characteristics of the 5(S), 12(S), 6-trans LTB4 isomer. These studies indicate that lipoxygenase products of arachidonic acid metabolism are present in the sputum in various forms of obstructive airways disease. The failure to detect the 'SRS-A' leukotrienes in sputum from bronchial asthma may be attributable to either losses during extraction, the insensitivity of the assay procedure or to more rapid catabolism of LTC4 and LTD4 by bronchial secretions in asthma than in cystic fibrosis.     

The influence oc glycocorticoid therapy on sputum ECP concentration in symptomatic patients with bronchial asthma

ECP released from the granules of activated eosinophils is regarded to be a marker of airway inflammation in asthma. The study was performed to compare the usefulness of measuring serum and sputum ECP for monitoring the asthma treatment. 29 subjects with mild to moderate asthma (mean age 41 +/- 17) were admitted in exacerbation (FEV1 55.54 +/- 87.49% N). 10 subjects with grass pollen asymptomatic asthma and 10 healthy subjects were also enrolled in the study. Patients with symptomatic asthma were ordered 30 mg prednisone for 2 weeks and they continued during next 2 weeks inhaled budesonide therapy. The concentrations of ECP (mcg/L) were determined by CAP-system (Pharmacia). The total eosinophil count and serum ECP in all subjects treated orally and next by inhaled GKS didn't differ statistically. The highest sputum ECP concentration was determined in exacerbation of asthma 84.5 +/- 78 mcg/L and statistically were reduced after 2-weeks of prednisone treatment 24.4 +/- 12.1 mcg/L (p = 0.05). In following 2 weeks of budesonide treatment sputum ECP concentration was statistically negligible in relation to previous treatment in spite of increasing tendency (50 +/- 61.3 mcg/L (p = 0.2394). In asymptomatic grass pollen asthma sputum ECP concentration was 19.7 +/- 9.4 mcg/L, higher than in controls 12 +/- 5.8 mcg/L (p = 0.04). There were a significant correlations between total eosinophil count and serum (r = 0.6396) and sputum ECP(r = 0.4683) in exacerbation. CONCLUSIONS: 1. In asthma exacerbation elevated sputum ECP concentration was observed. 2. In consequence of prednisone treatment the sputum ECP concentration was reduced. 3. Sputum ECP measurement is more accurate than serum ECP for monitoring the effectiveness of treatment. 4. Sputum ECP concentration is a sensitive parameter which discriminate asymptomatic patients with asthma from healthy subjects.     

Serum and sputum neurotrophin levels in chronic persistent cough

BACKGROUND: Neurotrophins (NTs) are a family of growth factors, including nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and neurotrophin3 (NT-3) that are involved in inflammation. Serum and induced sputum NT levels are increased in asthma and in cough because of idiopathic pulmonary fibrosis, respectively. Neurogenic inflammation is implicated in the pathogenesis of chronic cough in individuals with normal chest radiography, but the role of NTs in this condition is unknown. OBJECTIVE: To assess if NT levels are elevated in the serum and airways in subjects with chronic persistent cough. METHODS: Eighty-one subjects with chronic cough persistent for over 1 year; with normal chest radiography and spirometry were included. Thirty healthy subjects were controls. Serum NGF, BDNF and NT-3 were measured by enzyme immunoassay. In a subset, NGF was measured in induced sputum. Sputum cell counts and allergen-specific serum IgE were measured and all patients received specific sequential treatment trials to achieve a final diagnosis for the cough. RESULTS: There was no significant difference either in the levels of serum or sputum NTs in chronic cough subjects compared with controls or between the most common causes of cough: post-nasal drip syndrome, gastro-oesophageal reflux disease, asthma and bronchiectasis. The median (inter-quartile range) for sputum NGF (pg/mL) was 516 (296-772) in healthy controls and 580 (312-880) in subjects with chronic cough (P=0.284). There was no correlation between NT levels and sputum cell counts. Sputum NGF levels correlated with duration of cough (r=0.34, P=0.002). CONCLUSION: NTs are not elevated in induced sputum or serum of subjects with chronic persistent cough. This implies that NTs do not have a central role in perpetuating airway inflammation in chronic persistent cough.     

Effect of obesity on airway inflammation: a cross-sectional analysis of body mass index and sputum cell counts

BACKGROUND: Several observational studies have demonstrated an association between obesity and asthma. Studies evaluating exhaled nitric oxide levels and obesity have revealed that a higher body mass index (BMI) is associated with elevated exhaled nitric oxide levels. Airway inflammation using sputum cell counts has not been assessed in obese patients with airway diseases. OBJECTIVE: The primary aim of this study was to determine whether obesity (based on BMI) is associated with eosinophilic or neutrophilic bronchitis. METHODS: The results from a database of induced sputum cell counts were compared with BMI and analysed using correlation statistics, regression and parametric and non-parametric analysis. RESULTS: Seven-hundred and twenty-seven adult participants with an equal number of sputum samples were included in the analysis. BMI varied from 14.5 to 55 kg/m(2). Sputum total cell count (mean+/-SD: 12.9 x 10(6) cell/g+/-21.5), eosinophil percent (median; min to max: 0.3%; 0-89.0), and neutrophil percent (mean+/-SD: 63.5+/-26.6%) were within normal limits. Participants with asthma had a higher percentage of sputum eosinophils than those without asthma (P=0.01). However, there was no difference in the total or differential cell counts among the obese and non-obese participants, when the data were analysed according to BMI category, gender, dose of inhaled corticosteroid, and presence or absence of asthma. CONCLUSION: In this large sample of adult asthmatic and non-asthmatic participants, there was no association between BMI and airway inflammation measured by sputum cell counts. Other mechanisms to explain the relationship between obesity and asthma will need to be explored if this association is to be better understood.     

The small airway inflammation of asthmatic patients who have used dry powder type inhaled steroid for moderate-long term evaluated by induced sputum and the efficacy of HFA-BDP (QVAR) inhalation]

Although the dry powder type inhaled steroids, such as Fluticasone Propionate Diskhaler (FP-DH), FP Diskus (FP-DK), Budesonide Turbuhaler (BUD-TH), are widely distributed in daily clinical fields, we clinicians are required to evaluate whether it is effectively inhibiting inflammation of distal airway or not. We also investigated the effect of Hydrofluoroalukan-beclomethasone dipropionate (HFA-BDP), a new type of inhaled steroid which forms super micro aerosol particles, in the distal small airway. METHOD: 85 patients with moderate asthma, who daily used dry powder type inhaled steroid for at least more than 6 months with stable asthmatic condition, were the subject of this study. All subjects underwent sputum induction with the inhalation of 10% of hypertonic saline solution for 15 min and eosinophil counts and eosinophil cationic protein (ECP) in individual induced sputum were measured. Then, patients who had eosinophils detected in their induced sputum changed their previously inhaled steroid to HFA-BDP inhalation (400 i.g./day). Their eosinophil counts and the values of eosinophil cationic protein (ECP), Eotaxin, RANTES and neutrophil elastase (PMN-E) in their induced sputum were also examined before and 4weeks after changing HFA-BDP inhalation. RESULT: Increased eosinophils were found in the induced sputum of 40.5% patients of the FP-DK group, 36.3% of the FP-DH group and 32.4% of the BUD-TH group, respectively. Compared with group of patients in which no sputum eosinophil were detected, the sputum ECP values, in which sputum eosinophils were detected, were significantly high. 4 weeks after changing to HFA-BDP inhalation, eosinophil counts, ECP, Eotaxin, RANTES and PMN-E in their induced sputum were decreased in every group. CONCLUSION: Compared with the ordinary dry powder type inhaled steroids, HFA-BDP can effectively diminish distal airway inflammation, suggesting the possibility that HFA-BDP can effectively reach to the distal small airway by forming super micro aerosol particles.     

Airway inflammation in asthma and perennial allergic rhinitis. Relationship with nonspecific bronchial responsiveness and maximal airway narrowing

BACKGROUND: Eosinophilic airway inflammation is the hallmark of asthma, but it has also been reported in other conditions such as allergic rhinitis. We have tested whether the analysis of cells and chemicals in sputum can distinguish between patients with mild allergic asthma, those with allergic rhinitis, and healthy controls. The relationship between inflammation markers in sputum and nonspecific bronchial hyperresponsiveness to methacholine (BHR) (PD20 and maximal response plateau [MRP] values) was also evaluated. METHODS: We selected 31 mild asthmatics and 15 rhinitis patients sensitized to house-dust mite. As a control group, we studied 10 healthy subjects. Every subject underwent the methacholine bronchial provocation test (M-BPT) and sputum induction. Blood eosinophils and serum ECP levels were measured. Sputum cell differentials were assessed, and eosinophil cationic protein (ECP), tryptase, albumin, and interleukin (IL)-5 levels were measured in the entire sputum supernatant. RESULTS: Blood eosinophils and serum ECP levels were higher in asthma patients and rhinitis than in healthy controls, but no difference between asthma patients and rhinitis patients was found. Asthmatics had higher eosinophil counts and higher ECP and tryptase levels in sputum than rhinitis patients or control subjects. Sputum albumin levels were higher in asthmatics than in controls. Rhinitis patients exhibited higher sputum eosinophils than healthy controls. An association between sputum eosinophil numbers and MPR values (r= -0.57) was detected, and a trend toward correlation between sputum ECP levels and PD20 values (r= -0.47) was found in the rhinitis group, but not in asthmatics. No correlation between blood eosinophilic inflammation and lung functional indices was found. CONCLUSIONS: Induced sputum is an accurate method to study bronchial inflammation, allowing one to distinguish between rhinitis patients and mildly asthmatic patients. The fact that no relationship was detected between sputum inflammation and BHR suggests that other factors, such as airway remodeling, may be at least partly responsible for BHR in asthma.