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.     

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.     

Eosinophil markers in blood, serum, and urine for monitoring the clinical course in childhood asthma: impact of budesonide treatment and withdrawal

BACKGROUND: Markers of airway inflammation are needed for prediction of asthma deterioration and evaluation of disease severity. Few studies have focused on the dynamics of airway inflammation as reflected by the activity of the eosinophils and their proteins after withdrawal of inhaled corticosteroids. OBJECTIVE: Our goal was to investigate the effect of withdrawal of inhaled budesonide on eosinophil count in blood and eosinophil proteins in serum and urine and to relate the levels of these markers to the risk of symptoms of asthma, increased bronchial hyperresponsiveness, and deterioration of lung function. METHODS: Thirty-three children were randomly selected to continue or discontinue use of inhaled budesonide in a double-blind, placebo-controlled study. They were followed up for 4 months with regular analysis of blood, serum, and urine samples; lung function; and methacholine challenges. Eosinophil activity markers were analyzed. Age-matched healthy children provided reference data for all parameters measured. RESULTS: The eosinophil number in blood and eosinophil protein levels in serum (serum eosinophil cationic protein [ECP] and serum eosinophil peroxidase [EPO]) increased significantly in the withdrawal group, and the difference between the groups was significant (P =.02 for all). Twenty-nine percent of the children in the withdrawal group remained symptom free. This subgroup had eosinophil counts at baseline below 350/microL, a serum ECP level below 15 microg/L, and a serum EPO level below 25 microg/L, each of which was related to a low risk of exacerbation (relative risk = 0.37, 0.48, and 0.37 respectively; P <.05 for all). All eosinophil markers were lower in the healthy children than in the symptom-free children with asthma. CONCLUSION: Our data indicate that eosinophil count and/or ECP and EPO levels can be used to estimate the short-term risk of deterioration and the need for corticosteroid treatment in cases of mild and moderate allergic asthma.     

Safety and application of induced sputum analysis in childhood asthma

BACKGROUND: The value of sputum induction in pediatric asthma lies in its potential to directly and noninvasively assess airway inflammation in children, because bronchoscopy and biopsy carry some risk. The Childhood Asthma Management Program (CAMP) study was designed to evaluate the long-term effects of budesonide and nedocromil compared with placebo in children with mild to moderate asthma across 8 centers. OBJECTIVE: At the Denver CAMP site, we sought to evaluate the safety of sputum induction, to determine differences in airway inflammation between treatment groups by using induced sputum analysis, and to examine correlations between other biomarkers and sputum eosinophils. METHODS: Sputum induction was performed, and exhaled nitric oxide, circulating eosinophil counts, and serum eosinophil cationic protein were obtained at treatment discontinuation and after washout. Spirometry and a methacholine challenge were also performed according to the CAMP protocol. RESULTS: Ninety of 117 children provided an adequate sputum sample for analysis. In 9 subjects (3 nedocromil and 6 placebo), sputum induction resulted in bronchospasm. These subjects had greater disease severity, as measured by a lower median prebronchodilator FEV 1 percentage predicted (85.0% vs 96.0%; P =.024) and FEV 1 /FVC ratio (70.0% vs 79.0%; P =.0008); greater bronchodilator reversibility (16.5% vs 6.8%; P =.004); higher serum IgE (1390.0 vs 495.0 ng/mL; P =.017) and circulating eosinophil count (757.0 vs 282.0/mm 3; P =.04); greater use of prednisone (1.9 vs 0.9 courses per 100 person-years; P =.05); and greater supplemental inhaled steroid doses (85.3 vs 0 mg; P =.016). At treatment discontinuation, budesonide-treated patients had a lower median (1st, 3rd quartile) sputum percentage eosinophil (SPEos) (0.2% [0%, 1.2%] vs 0.8% [0.2%, 4.6%]; P =.03) compared with those treated with placebo; no significant difference was noted between nedocromil- and placebo-treated patients. Higher SPEos at the time of treatment discontinuation was associated with asthma worsening that required rescue prednisone (n = 23) during the washout period compared with patients who remained stable (3.6% [0.4%, 6.4%] vs 0.6% [0.2%, 3.2%] SPEos; P =.023). Finally, greater SPEos was associated with atopy, higher bronchodilator reversibility, lower FEV 1 /FVC ratio, higher exhaled nitric oxide levels, circulating eosinophils, sputum and serum eosinophil cationic protein, more prednisone courses during the treatment period, and greater asthma severity. CONCLUSIONS: Sputum induction is a relatively noninvasive and safe procedure that can provide information on eosinophilic inflammation and treatment response and is also associated with several measures of asthma control. However, this procedure still remains a research tool in asthma because of its requirements for technical expertise.     

Evaluation of serum eosinophil cationic protein as a predictive marker for asthma exacerbation in patients with persistent disease

BACKGROUND: Eosinophilic inflammation is a feature of asthma. However, serological markers to indicate eosinophil activation in this process are not fully defined. OBJECTIVE: To evaluate the relationship of serum eosinophil cationic protein (ECP) to asthma worsening and a marker for treatment effectiveness, 26 adult patients with an asthma exacerbation were identified. METHODS: Identified asthma subjects were treated with oral corticosteroids (prednisone) for 14 days. The lung function variables, forced expiratory volume in one second (FEV1) and peak expiratory flow (PEF), were determined as percentage of predicted and the blood total eosinophil count and serum ECP levels were measured. Patients were re-evaluated after 14 days of corticosteroid treatment and then every 3 months thereafter during a 12-month period. RESULTS: Eighteen patients responded to prednisone treatment, whereas eight did not, assessed as improvement of their lung function parameters. Different serum ECP patterns could be seen in the responders compared with the non-responders. All 18 responders had considerably increased serum ECP at the time of exacerbation, whereas the non-responders had lower serum ECP levels. The serum ECP levels decreased to a greater extent in the responder patient group than in the non-responder patients following prednisone treatment. This difference in patterns was not seen with total blood eosinophil counts. CONCLUSION: Our findings suggest that serum ECP may be used to predict a response to corticosteroid therapy in adult patients with asthma.     

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.     

Urinary eosinophil protein X in children with atopic asthma: A useful marker of antiinflammatory treatment

BACKGROUND: Bronchial asthma is associated with elevated serum levels of eosinophil products, such as eosinophil protein X (EPX), but the occurrence in urine of this substance in patients with asthma has not previously been studied. OBJECTIVE: This study was performed to clarify whether increased amounts of eosinophil granulocyte proteins in urine and serum reflect ongoing asthmatic inflammation and whether decreasing values reflect successful treatment. METHODS: Twelve children with a median age of 12.5 years who had mild or moderate atopic asthma were studied for 3 months. At the time of inclusion in the study, treatment with inhaled budesonide was initiated. Nine children of the same age without atopic disease served as control subjects. Levels of EPX, eosinophil cationic protein (ECP), and myeloperoxidase in serum and in urine (urinary EPX) were determined at inclusion and then after 3 months of treatment. Spirometry was performed on the same occasions. RESULTS: At the time of inclusion, urinary EPX and serum ECP were significantly higher in children with atopic asthma than in the control subjects (mean, 116.4 vs 43.0 μg/mmol creatinine [p = 0.004] and 37.0 vs 14.8 μg/L [p = 0.004]). In the asthma group urinary EPX, as well as serum ECP, decreased significantly after 3 months of treatment with budesonide (116.4 to 68.4 μg/mmol creatinine [p = 0.005] and 37.0 to 24.0 μg/L [p = 0.04]). At the same time, peak expiratory flow values increased significantly in the children with asthma (76.0% to 87.8% of predicted value [p = 0.005]) but not in the control subjects (87.0% to 90.1%). In the asthma group the levels of myeloperoxidase were similar to those in the control group, both at inclusion and after 3 months. CONCLUSION: Increased urinary EPX and serum ECP levels seem to reflect active atopic asthma, whereas decreased levels after antiinflammatory treatment probably reflect normalization of airway inflammation, and indirectly, improved lung function. (J Allergy Clin Immunol 1996;97:1179-87.)     

Nitric oxide metabolites in induced sputum: a marker of airway inflammation in asthmatic subjects

BACKGROUND AND OBJECTIVE: The role of nitric oxide (NO) needs to be further clarified in allergic inflammation. This study was designed to investigate the relationships between NO metabolites and eosinophil count, eosinophil cationic protein (ECP), interleukin (IL)-5 in induced sputum from asthmatics. METHODS: Hypertonic saline-induced sputum was obtained in 25 asthmatic subjects, among which 13 patients were examined before and after anti-asthmatic medications including steroid preparations. Ten normal subjects were enrolled as controls. Fresh expectorated sputum separated from saliva was treated with equal volume of dithiothreitol 0.1%, cytospinned for cell count, and the supernatant was collected for biochemical assay. NO metabolites were assayed by using modified Griess reaction. ECP was measured by fluoroimmunoassay, and detected IL-5 by a sandwich ELISA. RESULTS: Asthmatic subjects, compared with controls, had significantly higher concentration of NO metabolites (1035.4 +/- 125.3 vs 557.2 +/- 101.5 micromol/L, P < 0.01), higher percentage of eosinophils (25.6 +/- 4.6 vs 1.7 +/- 0.2%, P < 0.01), and higher levels of ECP (1117.8 +/- 213.9 vs 154.6 +/- 47.4 microg/L, P < 0.01) in the induced sputum. IL-5 was detected more frequently in asthmatic subjects than in control subjects (11/25 [44%] vs 1/10 [10%], P < 0.05). According to asthma severity, moderate to severe asthmatic subjects (n = 18) had higher level of NO metabolites (1143.8 +/- 156.3 vs 575.5 +/- 89.5 micromol/L, P < 0. 01), higher levels of ECP and IL-5 (P < 0.01, respectively) in the induced sputum than in those of mild asthmatic subjects (n = 7). NO metabolites, the percentage of eosinophils, the levels of ECP, and IL-5 were reduced following treatment with anti-asthmatic drugs (P < 0.01, respectively). There were significant positive correlations between NO metabolites and percentage of eosinophils or ECP (r = 0. 34, P < 0.05; r = 0.28, P < 0.05). Negative correlations were noted between FEV1, FEV1/FVC and proportion of eosinophils, ECP, or IL-5 levels. CONCLUSION: These findings confirmed that the level of NO metabolites was increased in the tracheobronchial secretion of asthmatic subjects and was paralleled with severity of asthma. Measurement of NO metabolites in induced sputum may be used for monitoring the degree of airway inflammation in asthmatics.     

Analysis of induced sputum before and after withdrawal of treatment with inhaled corticosteroids in asthmatic patients

To assess whether sputum eosinophilia predicts the recurrence of asthma symptoms after withdrawal of therapy in moderate stable asthmatics on low-dose inhaled corticosteroids. Randomized, double-blind, placebo-controlled study involving 30 subjects with stable asthma, asymptomatic, with low PEF variability measured over two run-in weeks, on treatment with low-dose inhaled beclomethasone dipropionate (BDP, 250 microgram b.i.d. in the last 3 months). At the end of the run-in, all patients underwent a methacholine challenge test and sputum induction (T1). They then stopped therapy and received either placebo (20 subjects, study group) or BDP at the same dose as in the previous 3 months (10 subjects, control group). They continued to monitor PEF and symptom score for 3 months, or until asthma symptoms recurred (diurnal and nocturnal symptom score >/=2 on two consecutive days). At the end of the study (T2), i.e., either within 5 days from the beginning of asthma symptoms or after 3 months in subjects without recurrence of asthma symptoms, all subjects repeated the methacholine challenge test and sputum induction. In the placebo-treated group, sputum eosinophils at T1 were significantly higher in subjects who subsequently developed recurrence of asthma symptoms (n = 7) after cessation of treatment than in subjects who remained asymptomatic for 3 months (8.2% [0-56.6] vs 0.9% [0-11], P < 0.05). At the time of recurrence of asthma symptoms, sputum eosinophil percentages significantly increased (from 8.2% [0-56.6] to 16.6% [5.8-73.6], P < 0.05). The positive predictive value of sputum eosinophils for the recurrence of asthma symptoms was 71%, while the negative predicting value was 84%. In the BDP-treated control group, none of the subjects experienced recurrence of asthma symptoms, and sputum eosinophil percentages measured at the beginning (T1) and at the end (T2) of the study were similar. Sputum eosinophil percentages may vary over a wide range in asthmatic subjects, although regularly treated and apparently well controlled. However, high sputum eosinophil percentages are related to early recurrence of asthma symptoms after cessation of inhaled corticosteroids.     

Diagnostic accuracy of sputum outcomes in chronic stable asthma

BACKGROUND: Asthma with non-remitting airflow obstruction may not always be differentiated from COPD with airway hyperreactivity. Many attempts have been made to find useful markers for the distinction between these two disorders. OBJECTIVE AND METHODS: In order to help the finding of a useful marker for the diagnosis of asthma in the population of patients with airway obstruction we analysed the diagnostic accuracy of sputum eosinophils and sputum ECP in 91 patients with asthma, 15 patients with chronic bronchitis, 32 patients with chronic obstructive pulmonary disease (COPD) and 20 controls subjects, by performing ROC analysis. RESULTS: Sputum eosinophils were above the normal range of our laboratory (0-3.7%) in 48 asthma patients and in six COPD patients, while sputum ECP (normal range < 85 microg/L) was high in 65 asthma patients, in 24 COPD patients and in nine chronic bronchitis patients. The ROC analysis revealed that sputum eosinophils count (AUC = 0.82) was more accurate than both sputum ECP levels (AUC = 0.56) (P < 0.0001) and beta2-reversibility (AUC = 0.53) (P = 0.0001) in differentiating asthmatic from non-asthmatic subjects (COPD, chronic bronchitis patients and normal subjects). The diagnostic accuracy of ECP was similar to that of bronchial reversibility (P = 0.76). When ROC analysis was performed by including only patients with airway obstruction (36 asthmatics with airway obstruction and COPD patients), both eosinophil count (AUC = 0.77) and beta2-reversibility (AUC = 0.66) were more accurate than ECP measurement (AUC = 0.39) in discriminating asthmatics from COPD patients (P < 0.00001 and P = 0.04, respectively). CONCLUSION: Sputum eosinophils seem to be valid markers for detecting asthma in a population of patients with airway obstruction. Moreover, the higher diagnostic accuracy of eosinophils in the sputum compared to sputum ECP and bronchial reversibility reinforces the role of cytological analysis of sputum in the diagnosis of chronic stable bronchial asthma.     

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.     

Cysteinyl-leukotrienes contribute to sputum eosinophil chemotactic activity in asthmatics

BACKGROUND: Cysteinyl-leukotrienes are lipid derived mediators involved in asthma. They are able to stimulate eosinophil chemotaxis in vitro. Induced sputum from asthmatics has been shown to contain eosinophil chemotactic activity. The purpose of our study was to evaluate the contribution of cysteinyl-leukotrienes to sputum eosinophil chemotactic activity in asthmatics and to seek whether there might be differences between asthmatics free of inhaled corticosteroids vs those regularly receiving this treatment. METHODS: Twenty-two patients (11 corticosteroid free, mean FEV1 99% predicted, 11 corticosteroid-treated, mean FEV1 77% predicted) recruited from our asthma clinic underwent a sputum induction. Sputum was processed according to standard procedure. Eosinophil chemotactic activity contained in the fluid phase was assessed using Boyden microchamber model and expressed as chemotaxis index (CI). Cysteinyl-leukotrienes were measured in sputum supernatant by ELISA and their role in sputum eosionophil chemotactic activity was evaluated by using montelukast, a selective antagonist of a cys-LT1 receptor. RESULTS: Cysteinyl-leukotrienes were well detectable in sputum supernatants from both steroid-naive (247 +/- 42 pg/ml) and steroid-treated (228 +/- 26 pg/ml) asthmatics. Sputum eosinophil chemotactic activity was indiscriminately present in both corticosteroid-naive (CI: 2.61 +/- 0.22) and corticosteroid-treated (2.98 +/- 0.35) asthmatics. Montelukast (100 microM) significantly inhibited the eosinophil chemotactic activity in both groups achieving a mean inhibition of 54.2 +/- 9.2% (P < 0.001) and 64.7 +/- 7.8% (P < 0.001) in steroid-naive and steroid-treated asthmatics respectively. CONCLUSION: Cysteinyl-leukotrienes actively participate in sputum eosinophil chemotactic activity found in asthmatics irrespective of whether they are or not under treatment with inhaled corticoids.     

Induced sputum in children with newly diagnosed mild asthma: the effect of 6 months of treatment with budesonide or disodium cromoglycate

BACKGROUND: There are few controlled studies on the effects of anti-inflammatory treatment on airway inflammation in newly diagnosed childhood asthma. METHODS: Sixty children with newly diagnosed mild persistent asthma, 5-10 years of age, and 17 healthy control subjects were studied. Asthmatic children were randomized into an open study with two treatment groups: (1) budesonide 400 microg twice daily for 1 month, 200 microg twice daily for 5 months and (2) disodium cromoglycate (DSCG) 10 mg three-times daily for 6 months. All exacerbations were treated with budesonide 400 microg twice daily for 2 weeks. Symptoms and lung function were recorded throughout the study. RESULTS: Sputum induction was safe and the overall success rate was 71%. This improved with age and decreased after treatment. At baseline, the asthmatic children had more eosinophils in blood (0.26 vs 0.18 x 10(9)/l, P = 0.03) and sputum (1.1 vs 0.0 %, P = 0.0001) than the control subjects. The numbers of sputum eosinophils correlated with bronchial responsiveness (R = -0.58, P = 0.0002). Eosinophils were higher in children with atopic asthma than with nonatopic asthma (P < 0.0001), and in children with a history wheezing than in children without wheezing (P = 0.02). Six months of budesonide treatment, but not of DSCG, improved lung function (P = 0.007), decreased symptoms (P = 0.007) and sputum eosinophils (P = 0.003). The effects of budesonide were pronounced in children with intense sputum eosinophilia (>3%). CONCLUSION: Sputum eosinophilia is present in children with newly diagnosed mild persistent asthma. Treatment with inhaled budesonide, but not with DSCG, decreases sputum eosinophils along with clinical and functional improvement.     

A single nasal allergen challenge increases induced sputum inflammatory markers in non-asthmatic subjects with seasonal allergic rhinitis: correlation with plasma interleukin-5

BACKGROUND: Seasonal allergic rhinitis (SAR) is a risk factor for asthma in affected individuals. Nasal allergic inflammation enhances bone-marrow eosinophil production, mainly via IL-5, and rhinitis patients have increased airway inflammation during the pollen season. OBJECTIVE: To assess the impact of nasal allergy on sputum inflammatory markers. METHODS: In an open-labelled, randomized, placebo-controlled cross-over study with 16 non-asthmatic SAR patients (median age 25 years, 56% males), the effect of a single nasal allergen challenge performed out of season on induced sputum inflammatory parameters was evaluated. SAR patients were identified by history, skin-prick test and specific IgE. All patients had normal lung function/bronchial hyper-responsiveness out of season and a negative asthma/wheezing history. Sputum cells and supernatant levels of ECP, sICAM, IL-5 and IL-10, and plasma levels of IL-5 and ECP, were measured before and 24 h after nasal allergen challenge. After a washout period of at least 4 weeks, the procedure was repeated with placebo challenge (diluent). RESULTS: Nasal allergen challenge led to an increase in sputum ECP (pre = 60 +/- 12, post = 212 +/- 63 micro g/L, P = 0.02 vs. placebo), and sICAM (4.8 +/- 2.7 to 6.5 +/- 2.9 ng/mL, P = 0.02 vs. placebo), whereas IL-10 decreased after provocation (44 +/- 11 to 29 +/- 6 pg/mL, P = 0.06 vs. placebo). Sputum IL-5 was undetectable in all patients. The absolute number of blood and sputum eosinophils did not change significantly after allergen or placebo challenge (P > 0.07, both comparisons). Plasma levels of IL-5 increased after allergen challenge (8.7 +/- 2.9 to 14.5 +/- 3.9 pg/mL, P = 0.001), and the increase in plasma IL-5 was positively correlated with the rise in sputum ECP in a subgroup of 'responders' (n = 12, r = 0.71, P = 0.01). CONCLUSIONS: A single nasal allergen challenge in SAR patients increased markers of allergic inflammation in the lower respiratory tract, possibly via pronounced activation of inflammatory cells through circulating immediate-type reaction cytokines like IL-5. These findings may provide additional explanatory data for the high susceptibility of SAR patients to incident asthma.     

Naturally occurring parainfluenza virus 3 infection in adults induces mild exacerbation of asthma associated with increased sputum concentrations of cysteinyl leukotrienes

BACKGROUND: Viral respiratory tract infections represent the most frequent cause of asthma exacerbation in both children and adults, but the precise mechanism of such exacerbation remains unknown. OBJECTIVES: To determine the critical mediator of naturally occurring parainfluenza virus (PIV) 3-induced mild asthma exacerbations in adults. METHODS: The study subjects were 19 adult asthmatics with mild asthma exacerbation (peak expiratory flow = 60-80% of predicted before bronchodilator use and >80% of predicted after initial bronchodilator treatment). Differential cell counts and concentrations of inflammatory markers including eosinophil cationic protein (ECP), cysteinyl leukotrienes (cysLTs), interleukin (IL)-5, IL-10 and IL-12 were measured in the induced sputum obtained from adults with PIV3- (n = 9) and non-cold-induced (n = 10) exacerbation of asthma during both acute and convalescent phases. RESULTS: PIV3 infection was confirmed by the presence of viral RNA in nasopharyngeal aspirates. Mild exacerbation of asthma was not associated with significant changes in sputum differential cell counts. Concentrations of sputum ECP and cytokines were comparable between PIV3 and non-cold-induced patients. In contrast, PIV3 infection was associated with a significant increase in sputum cysLTs during the acute phase of mild asthma exacerbation. CONCLUSIONS: Our results identified cysLTs as a critical mediator of PIV3-induced acute asthma exacerbation.     

Eosinophils in exercise-induced asthma

The variations in serum levels of eosinophil cationic protein (ECP) have been measured after exercise challenge of 13 patients with asthma with exercise-induced asthma (EIA) and nine patients with asthma without EIA. The patients were treated before exercise in a randomized and blinded fashion with inhalation of one dose of either disodium chromoglycate, terbutaline, or budesonide and in an open study with 4 weeks of inhaled budesonide. In the group with EIA, there was, in some patients, an initial increase in serum levels of ECP after exercise, but 60 minutes after exercise, the levels were significantly reduced (p less than 0.001). Disodium chromoglycate and 4 weeks of budesonide treatment inhibited this reduction. Histamine challenge of the group with EIA produced a similar fall in serum ECP levels (p less than 0.001). The group without EIA had initially lower levels of ECP than the group with EIA (p less than 0.05 to p less than 0.01), and ECP stayed unaltered after exercise. The preexercise serum ECP levels correlated significantly to the maximal fall in peak expiratory flow in the untreated group (r = 0.91; p less than 0.001) and in the group receiving one dose of budesonide (r = 0.62; p less than 0.05). The blood eosinophil counts were unchanged after challenge and not related to lung function. The results suggest that the ECP content in serum reflects the degree of allergic inflammation in the lungs and thereby the degree of bronchial hyperreactivity.     

Detection and treatment of early asthma

Background: We sought answers to two questions: 1) how can mild, early asthma best be detected? 2) how should it be treated and the treatment effect monitored? Methods: Eighty adult patients with early, mostly mild asthma and 30 control subjects were examined by lung‐function and biochemical tests. Patients were randomly assigned to two treatment groups. One group was treated with an inhaled steroid (budesonide) for 6 weeks, and the other first with an inhaled β₂‐agonist (terbutaline) for 6 weeks and then with an inhaled steroid for 2 weeks. Results: Treatment with budesonide was effective: symptom scores, PEF, blood eosinophils, and sputum ECP values all improved. Terbutaline was ineffective by these criteria. For the detection of early asthma and for the following treatment effects, sputum and serum ECP assays are useful supplements to lung‐function tests. Conclusions: Treatment of early, mild asthma with an inhaled steroid is effective and worthwhile. Detection of the disease remains a problem, as both lung‐function and biochemical tests have low sensitivities.     

Nitric oxide metabolites,eosinophils, and eosinophilic cationic protein in patients with asthma: sputum versus blood

The monitoring of airway inflammation has assessed in bronchial asthma directly by sputum examination, and indirectly by measurements in peripheral blood. To investigate the diagnostic value of these two methods, we compared nitric oxide (NO) metabolites, eosinophils, and eosinophil cationic protein (ECP) in sputum and blood in patients with asthma and control subjects. Sputum and serum were obtained from fifteen patients with asthma, and then were examined before anti-asthma treatment, including steroid preparations. ECP was measured by fluoroimmunoassay. NO metabolites were assayed by using modified Griess reaction. Asthmatic patients, compared with control subjects, had significantly higher level of NO metabolites, higher proportion of eosinophils, and higher levels of ECP in sputum. Asthmatic patients, compared with control subjects, however, had significantly higher number of eosinophils, and were at higher levels of ECP in blood. FEV1, FEV1/FVC was negatively correlated with sputum eosinophils. The area under receiver operating characteristic (ROC) curve showed that eosinophils in sputum are significantly accurate markers than NO metabolites in sputum and blood. These findings suggest that the proportion of eosinophils in sputum have more accurate diagnostic marker of asthmatic airway inflammation than NO metabolites in sputum in differentiating asthmatic patients from control subjects.     

Blood eosinophil numbers and activity during 24 hours: effects of treatment with budesonide and bambuterol.

The effects of the inhaled corticosteroid budesonide and the oral long-acting beta-agonist bambuterol on circadian variation of blood eosinophil numbers, serum levels of eosinophil cationic protein (ECP), serum eosinophil chemotactic activity (ECA), and serum neutrophil chemotactic activity (NCA) were studied in two groups of patients with allergic asthma. Group 1 (n = 8) had a circadian variation of peak expiratory flow (PEF) 15% or greater, and group 2 (n = 9) had a circadian PEF variation less than 15%. Both groups were randomized and crossover treated for 4 weeks with (A) 0.4 mg budesonide at 8 AM and 8 PM, (B) 20 mg bambuterol at 8 PM, and (C) placebo. At the end of each period blood eosinophil numbers, ECP, ECA, and NCA were measured during 24 hours at 4-hour intervals. No significant differences in the inflammatory parameters could be observed between the groups, although eosinophil numbers tended to be higher in group 1 than in group 2. Highest eosinophil numbers were observed at night. Budesonide reduced both eosinophil numbers and ECP levels, especially at night; bambuterol had no effect on both variables. No circadian variation or treatment effects were observed for ECA and NCA. This study suggests a role for the eosinophil in the nocturnal worsening of asthma, and it demonstrates that budesonide produces, in contrast to bambuterol, a reduction of (nocturnal) eosinophil numbers and activity.     

Once-daily theophylline reduces serum eosinophil cationic protein and eosinophil levels in induced sputum of asthmatics

BACKGROUND: Because eosinophilic airway inflammation is a characteristic feature of bronchial asthma, the treatment of airway inflammation is important in the management of asthma. Theophylline has been reported to reduce airway inflammation, in addition to its well-known bronchodilating effect. OBJECTIVE: In order to evaluate the effects of theophylline on airway inflammation, we investigated 48 subjects with mild and moderate asthma. METHODS: The patients were randomly divided into two groups, with or without theophylline treatment (control n = 24; theophylline, n = 24). We examined the level of serum eosinophil cationic protein (ECP), induced sputum samples, and peak expiratory flow (PEF) and obtained spirograms before and after 4 weeks of treatment with once-daily theophylline (200-600 mg/day) of subjects with mild or moderate asthma. RESULTS: Theophylline significantly increased morning and evening PEF and significantly decreased the diurnal variation of PEF. After treatment with theophylline, both serum ECP and the percentage of eosinophils in induced sputum were significantly decreased. In contrast, peripheral blood eosinophil count was unchanged after treatment with theophylline. Conclusions: These findings suggest that theophylline reduces airway inflammation and the severity of asthma, presumably via suppression of both eosinophil activity and subsequent eosinophil infiltration of the airways.