Urinary LTE4 is higher after nasal provocation test with L-ASA in bronchial than in only nasal responders.

UNLABELLED: Aspirin induced asthma (AIA) is a syndrome characterised by intolerance to acetylsalycilic acid (ASA), nasal polyps and bronchial asthma, being the metabolic shift of arachidonic acid toward the lipoxygenase pathway and hyper-production of cysteinyl-leukotrienes (cys-LTs) the current pathogenetic hypothesis. The research for both sensitive indicators and safe diagnostic tests is still attracting. Aim of the study was to compare the levels of urinary LTE4 in baseline and after Nasal Provocation Test (NPT) with L-ASA from subjects affected by aspirinin-Intolerance and characterized by only a nasal response to ASA to those from subjects with both a nasal and a bronchial response to the same challenge. METHODS: After their written consent, 74 subjects with mill to moderate AIA (16 male, mean age 45.3 years +/- 12.3 sd, mean basal FEV1 = 78.1% pred. +/- 6.2.4sd, FEV1 reversibility = 14.3% bsln +/- 2.1 ds after salbutamol 200 mcg) performed a NPT with L-ASA (total maximal dose 25 mg). Spirometry (FEV1), acoustic rinometry (nasal volume--VOL; nasal Resistance--Req; AR; TM Hood Lab., USA), and urinary LTE4 (Cayman Chemical, MI, USA, via Triturus System, Grifols, Spain) were checked in all subjects in basal conditions and 90' after NPT. STATISTICS: t test between means +/- sd, assuming p < 0.05, and linear regression between all variables considered. RESULTS: In 69 ASA-intolerant-asthmatics, mean FEV1 did not change significantly following NPT (78.7% pred. +/- 5.1 sd in baseline; 78.5% pred. +/- 4.1 sd after NPT, p = ns) even though in the presence of a significant decrease of VOL. (12.6 cm3 +/- 4.1 sd in baseline; 6.2 cm3 +/- 4.6 sd after NPT, p = 0.003); of a substantial increase in Req (0.9 cm H2O/l/min +/- 0.1 ds in baseline; 2.4 cmH2O/l/min +/- 0.2 after NPT, p = 0.04), and of urinary LTE4 excretion (333.0 pg/mg +/- 161.7 in bsln; 558.0 pg/mg +/- 171.690' after NPT with L-SA, p = 0.02). In only 5 subjects, the nasal response occurred concomitantly to a significant bronco-constriction after the NPT: mean FEV, changed from 77.9% pred. +/- 3.9 in bsln to 46.6% pred. +/- 4.3 after NPT (p < 0.001); mean VOL from 13.9 cm3 +/- 4.7 sd to 5.6 cm3 +/- 2.8 sd (p < 0.001); mean Req from 1.1 cmH2O/l/min +/- 0.2 in bsln to 2.5 cmH2O/l/min +/- 0.4 after NPT (p = 0.02) in these subjects. In ASA-intolerant bronchial responders, the severity of respiratory reactions proved related to the extent of urinary LTE4 response, which on the other hand, proved significantly higher than that observed in ASA-intolerant subjects with only nasal response and in ASA-tolerant subjects (LTE4 from 333.0 pg/mg +/- 161.7 in baseline up to 558.0 pg/mg +/- 171.6 90 min. following the NPT with L-ASA the nasal-responders, p = 0.04, but from 412.0 pg/mg +/- 102.8 in baseline up to 978.0 pg/mg +/- 108.7 after NPT in bronchial responders, p < 0.001 from baseline). CONCLUSIONS: Nasal challenge with ASA affects significantly both nasal VOL and Req, and LTE4 excretion in all ASA-intolerant subjects. During the nasal challenge, severity of respiratory reactions proves associated with the highest basal LTE4 synthesis. This feature reflects a spectrum of respiratory tract reactions where cysteinil-LTs can play a specific diagnostic role.

[Clinical significance of measurement of urinary leukotriene E4 in asthmatic patients without attack].

To evaluate clinical significance of measurement of urinary leukotriene E4 (LTE4) in asthmatic patients without attack, we measured urinary LTE4 in 68 asthmatic patients without attack and investigated its correlation with severity of asthma, % FEV1, bronchial hyperresponsiveness and peripheral eosinophil counts. Values of urinary LTE4 were significantly higher in the asthmatic patients (113.6 +/- 9.7 pg/mg.cr) than in healthy control subjects (67.8 +/- 4.7, n = 31), and the level of urinary LTE4 was in proportion to the severity of disease. Urinary LTE4 showed significant negative correlation with % FEV1 in atopic patients (Rs = -0.43, p = 0.025, n = 28), which was not recognized in non-atopic patients. Urinary LTE4 showed no significant correlation with bronchial hyperresponsiveness and peripheral eosinophil counts. Our findings suggested that basal LTE4 in urine reflected chronic airway inflammation of asthma.

Efficacy of leukotriene receptor antagonist in bronchial hyperresponsiveness and hypersensitivity to analgesic in aspirin-intolerant asthma.

BACKGROUND: Albeit its exact pathogenesis is still ambiguous; aspirin-intolerant asthma is one of several types of asthma for which antileukotriene therapy is useful, because it is widely accepted that bronchial over-production of leukotrienes may be involved in its pathogenesis. Pranlukast (8-[p-(4-phenylbutyloxy) benzol] amino-2-(tetrazol-5-yl)-4-oxo-4H-1-benzopyran hemihydrate), a selective cysteinyl leukotriene receptor antagonist, is now widely used in the treatment of asthma. OBJECTIVE: This study was designed to investigate the protective effect of pranlukast on airway sensitivity to sulpyrine provocation testing, bronchial responsiveness to methacholine provocation testing, and to investigate whether this protective activity is associated with a reduction in aspirin-induced excretion of urinary LTE4 (uLTE4), a marker of the cysteinyl leukotriene (LT) overproduction that participates in the pathogenesis of aspirin-induced asthma. METHODS: We assessed the effects of pretreatment with pranlukast on bronchoconstriction precipitated by inhalation of methacholine and sulpyrine in 16 adult patients with mild or moderate aspirin-intolerant asthma; those who were in stable clinical condition and were hypersensitive to sulpyrine provocation testing were allocated to this study. A double-blind, randomized, crossover design was used. uLTE4 was measured using combined reverse-phase high-performance liquid chromatography (rp-HPLC)/enzyme immunoassay. RESULTS: Pranlukast protected against analgesic-induced bronchoconstriction through mechanisms that were not related to the bronchodilator property, but were related to the improvement both of bronchial hyperresponsiveness and hypersensitivity to analgesic (P < 0.005 and P < 0.0001). Pranlukast showed little effect on excretion of uLTE4. CONCLUSION: These results support the hypothesis that cysteinyl leukotriene is one of the most important components in the pathogenesis of aspirin-intolerant asthma. Pranlukast improves not only hypersensitivity to analgesic, but also bronchial hyperresponsiveness in aspirin-intolerant asthma. It is also possible that pranlukast has another anti-asthmatic effect besides that of a leukotriene receptor antagonist.

Bronchial hyperresponsiveness, hypersensitivity to analgesics and urinary leukotriene E4 excretion in patients with aspirin-intolerant asthma.

This study was designed to investigate the protective effect of cromolyn sodium on airway sensitivity to sulpyrine, and bronchial responsiveness to methacholine, and to investigate whether this protective activity is associated with reduction in aspirin-induced excretion of urinary leukotriene E4 (u-LTE4), a marker of the cysteinyl LT overproduction that participates in the pathogenesis of aspirin-induced asthma. We assessed the effects of pretreatment with cromolyn sodium on bronchoconstriction precipitated by inhalation of methacholine and sulpyrine in 16 adult patients with mild or moderate aspirin-intolerant asthma; those who were in stable clinical condition and were hypersensitive to a sulpyrine provocation test were included in this study. A double-blind, randomized, crossover design was used. u-LTE4 was measured using combined reverse-phase high-performance liquid chromatography enzyme immunoassay. Cromolyn sodium protected against analgesic-induced bronchoconstriction through mechanisms that are not related to its bronchodilator property, but to the improvement of both bronchial hyperresponsiveness and hypersensitivity to analgesics (p<0.01 and p<0.001). Although excretion of u-LTE4 did not increase after the methacholine provocation test, it significantly increased after sulpyrine provocation (p<0.01). Furthermore, after pretreatment with cromolyn sodium, the maximum level of u-LTE4 after the sulpyrine provocation test was significantly lower than in controls (p<0.01). These results support the hypothesis that cysteinyl LT is one of the most important components in the pathogenesis of aspirin-intolerant asthma. Cromolyn sodium improves both hypersensitivity to analgesics, and bronchial hyperresponsiveness in aspirin-intolerant asthma.

Possible interaction between exposure to environmental tobacco smoke and therapy in children with asthma.

1. The aim of the study was to determine the carbachol and albuterol responsiveness in treated and untreated asthmatic and allergic children exposed to environmental tobacco smoke assessed by urinary cotinine measurements. 2. Forty-six asthmatic and allergic children with normal spirometric values were recruited. The doubling dose, concentration of carbachol producing a 2-fold increase in specific airway resistance (SRaw) was determined and 200 micrograms of albuterol were administered via a Volumatic(R) spacer. The percentage of bronchodilatation was defined as the difference between the largest obtained SRaw and the post-beta2 SRaw divided by the largest SRaw. Data were compared by a Mann-Whitney U-test. 3. The 23 children with a high urinary cotinine, compared with the 23 children without urinary cotinine, had a decreased doubling dose (108.2+/-14.7 micrograms versus 160.9+/-19.5 micrograms; P=0.04) and an increased percentage of bronchodilatation (74.8+/-1.4% versus 68.8+/-1.8%; P=0.03). A prophylactic anti-inflammatory treatment induced a weaker bronchial reactivity to carbachol and a slightly greater bronchodilatation in children exposed to environmental tobacco smoke. 4. Environmental tobacco smoke increases bronchial reactivity in asthmatic and allergic children. This effect might be reduced by anti-inflammatory therapy. The bronchodilator response may be enhanced in exposed children and may be caused by one or several direct interactions between tobacco smoke compounds and albuterol.

Dietary sodium intake and the risk of airway hyperreactivity in a random adult population.

BACKGROUND: High dietary sodium intake has been identified as a potential cause of asthma and airway hyperreactivity. This study was designed to test the hypothesis that dietary sodium intake is an independent determinant of the risk of hyperreactivity in the general population, and to assess the role of atopy in the association between these factors. METHODS: Airway reactivity to methacholine, atopy, 24 hour urinary sodium excretion, and self-reported smoking and symptom history were measured in a random sample of 1702 adults aged 18-70 from an administrative district of Nottingham. Hyperreactivity was defined as a PD20FEV1 of 12.25 mumol or less, and atopy was defined quantitatively as the mean allergen skin weal response to Dermatophagoides pteronyssinus, cat fur, and grass pollen, and categorically as the occurrence of any allergen response 1 mm or greater than the saline control. Multiple logistic regression analysis was used to estimate the independent relative odds of hyperreactivity, atopy, or symptoms in relation to sodium excretion in all 1702 subjects, and multiple linear regression to assess the independent relation between sodium excretion and mean allergen skin weal diameter, and the PD20 value amongst hyperreactive subjects. RESULTS: There was no relation between the relative odds of hyperreactivity to methacholine and 24 hour urinary sodium excretion, either before or after adjustment for age, smoking, allergen skin weal diameter, and sex, and similarly no relation if the analysis was restricted to men or women only. The relative odds of having at least one allergen skin test response 1 mm greater than the saline control were increased in relation to sodium excretion after adjustment for age, sex, and smoking by a ratio of 2.08 (95% CI 1.04 to 4.15) per log10 unit increase in sodium excretion, but there was no evidence of an association between sodium excretion and the occurrence of self-reported wheeze, hay fever, eczema, or asthma. There was no relation between 24 hour sodium excretion and the magnitude of the mean allergen skin weal response or the PD20 value. CONCLUSIONS: These findings do not support the hypothesis that a high dietary sodium intake is a risk factor for airway hyperreactivity or atopic disease in the general adult population.

Urinary leukotriene E4 in bronchial asthma.

Leukotriene E4 (LTE4) is excreted into the urine in a relatively constant proportion of 4-7% when either leukotriene C4 (LTC4) or LTE4 is intravenously infused, regardless of the magnitude of the infused dose. Measurement of LTE4 in urine is, therefore, a convenient and non-invasive method for assessing changes in the rate of total body sulphidopeptide leukotriene production. We assayed urinary LTE4 in 17 normal subjects, 31 subjects with asthma without aspirin sensitivity, and 10 aspirin-sensitive subjects. The relationship between urinary LTE4 and nonspecific bronchial hyperresponsiveness, as assessed by the provocative dose producing a 20% fall in forced expiratory volume in one second (PD20) to inhaled histamine, was examined in 19 non-aspirin-sensitive asthmatic subjects. The urinary LTE4 values were log-normally distributed. Urinary LTE4 was detected in 28 of the 31 non-aspirin-sensitive asthmatic subjects, and the geometric mean (95% confidence interval (CI) of 43 (32-57) pg.mg-1 creatinine was no different to that of 34 (25-48) pg.mg-1 creatinine measured in the normal subjects. The geometric mean of 101 (55-186) pg.mg-1 creatinine measured in the aspirin-sensitive asthmatics was significantly higher than that measured in the normal subjects (p less than 0.005) and in the asthmatic subjects who were non-aspirin-sensitive (p less than 0.002), but there was considerable overlap between the three groups. There was no relationship between urinary LTE4 and PD20, or between urinary LTE4 and baseline forced expiratory volume in one second (FEV1) (% predicted). Thus, measurement of LTE4 in a single sample of urine will not predict the extent of bronchial hyperresponsiveness or degree of airflow obstruction.

A comparative study in atopic subjects with asthma of the effects of salmeterol and salbutamol on allergen-induced bronchoconstriction, increase in airway reactivity, and increase in urinary leukotriene E4 excretion.

Salmeterol (SM) is a novel beta 2-adrenoceptor agonist with a duration of action in excess of 12 hours. Evidence from in vitro studies has also demonstrated that, unlike the short-acting beta 2-agonists, such as salbutamol (SB), it may have some anti-inflammatory properties. With a randomized, double-blind, crossover design, we have compared the inhibitory effects of SM (50 micrograms) and SB (200 micrograms) delivered by metered-dose inhaler on allergen-induced bronchoconstriction, changes in airway reactivity, and urinary leukotriene (LT) E4 excretion in 12 atopic subjects with mild asthma. The immediate bronchoconstriction to allergen was significantly reduced by both beta 2-agonists (p less than 0.005), when reduction was expressed either in terms of maximum fall in FEV1 at 15 minutes after allergen (percent fall in FEV1, mean +/- SEM: 6.2 +/- 4.9, SM; 5.7 +/- 2.5, SB; 40.4 +/- 6.3, placebo) or the area under the FEV1 time curve (AUC) for the first 120 minutes after allergen. Four hours after challenge, results in the SB-treated and placebo-treated groups were not significantly different and demonstrated a small persistent bronchoconstriction compared to bronchodilatation in the SM-treated group (percent fall in FEV1, respectively, 9.3 +/- 3.7, 14.3 +/- 7.1, and -6.3 +/- 2.7; p less than 0.005, SM versus SB; p less than 0.02, SM versus placebo). Expressed in terms of AUC, only SM significantly reduced bronchoconstriction in the period 120 to 240 minutes after allergen (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)