Urinary leukotriene E4 levels in atopic and non-atopic preschool children with recurrent episodic (viral) wheezing: a potential marker?

UNLABELLED: Backround: Reliable biological markers for the differentiation of asthma phenotypes in preschool children with wheezing are lacking. The purpose of the study is to assess the relationship of urinary Leukotriene E4 (U-LTE4) to particular asthma phenotypes in preschool children with recurrent episodic (viral) wheezing following upper respiratory tract infections with or without atopic predisposition. METHODS: Ninety-six preschool patients with recurrent episodic wheezing participated, 52 atopic and 44 non-atopic, during exacerbation and in remission. Exacerbation was defined on clinical basis (wheeze in the presence of coryzal symptoms). Atopy was determined by specific serum IgE measurement and skin-prick testing. U-LTE4 was determined by enzyme immunoassay. Thirty-six age-matched, non-asthmatic, non-atopic children served as controls. RESULTS: During exacerbation, U-LTE4 was significantly higher in all children with recurrent episodic wheezing in comparison to A: Remission: 642.20 ± 268 versus 399.45 ± 204, p value <0.001 and B: CONTROLS: 642.20 ± 268 versus 271.39 ± 83, p value <0.001. Atopic patients demonstrated significantly higher levels of U-LTE4 compared to non-atopic, both during exacerbation 872.13 ± 246 versus 613.15 ± 150, p value = 0.0013 and during remission 507.59 ± 182 versus 283.59 ± 160, p value <0.001. During remission, a highly significant difference of U-LTE4 was found when controls were compared to atopic patients: 271.39 ± 83 versus 507.59 ± 182, p value = 0.002 but not when compared to non-atopic ones: 271.39 ± 83 versus 283.59 ± 160, p value = 0.432. CONCLUSION: U-LTE4 is strongly associated with the acute wheeze episode in preschool children, more so in atopics. Increased basal levels of U-LTE4 occur only in atopics. This suggests a potential role of U-LTE4 as a marker of atopic, virus-induced asthma in preschool children.

Cortisol and proinflammatory cytokine profiles in type 1 (reversal) reactions of leprosy.

PURPOSE: Cortisol levels in the circulation and at the sites of peripheral inflammation regulate type 1 (Reversal) reactions in leprosy akin to delayed type hypersensitivity reactions (DTH). In this study we determine the extent to which the differential mRNA expression of genes encoding cortisone-cortisol shuttle enzymes (11 ß hydroxysteriod dehydrogenase I & II (11 ß HSD I & II)), circulatory levels of proinflammatory cytokines (IL-6, IL-7, IP-10, IL-17F, IL-23, TNF-α, IL-1ß, PDGF BB and CRP) and cortisol are associated with development of type 1 reactions in leprosy. METHODS: Urine, blood and incisional skin biopsy samples from site of lesions were collected from 49 newly diagnosed untreated leprosy cases in T1R and 51 cases not in reaction (NR). mRNA expression levels of genes encoding 11 ß HSD I & II in skin biopsy samples were determined by realtime PCR. Cortisol levels from the lesional skin biopsies, serum and urine samples and serum proinflammatory cytokine levels were measured using ELISA. RESULTS: The mean expression ratios of 11 ß HSD I & II are significantly lower in leprosy cases with T1R when compared to the NR leprosy cases. Cortisol levels in lesional skin biopsies and in urine are significantly lower (p=0.001) in leprosy cases with T1R. Serum cytokine levels of IP-10, IL-17F, IL-IL-6 and TNF-α are significantly higher (p<0.05) in leprosy cases with T1R when compared the NR leprosy cases. CONCLUSION: Our study indicated an association of urinary and lesional skin cortisol levels with the manifestation of T1R in leprosy. IP-10, IL-17F, IL-6 and TNF-α can be potential prognostic serological markers and gene expression markers for early detection of type 1 reactions in leprosy.

Elevated eosinophil protein X in urine from healthy neonates precedes development of atopy in the first 6 years of life.

RATIONALE: Biomarkers predicting development of atopic disease are needed for targeted preventive measures and to study if disease pathology may be active before onset of symptoms. OBJECTIVES: To investigate whether eosinophil protein X, leukotriene-C4/D4/E4, and 11ß-prostaglandin (PG) F2α (PGD2 metabolite) assessed in urine from healthy at-risk neonates precede development of atopic disease during the first 6 years of life. METHODS: We measured eosinophil protein X (n = 369), leukotriene-C4/D4/E4 (n = 367), and 11ß-PGF2α (n = 366) in urine from 1-month-old children participating in the Copenhagen Prospective Studies on Asthma in Childhood birth cohort. Clinical data on development of allergic sensitization, allergic rhinitis, nasal eosinophilia, blood eosinophilia, eczema, troublesome lung symptoms (significant cough or wheeze or dyspnea), and asthma were collected prospectively until age 6 years. Associations between urinary biomarkers and development of atopic traits were investigated using general estimating equations, logistic regression, and Cox regression. MEASUREMENTS AND MAIN RESULTS: Eosinophil protein X in the urine of the asymptomatic 1-month-old neonates was significantly associated with development of allergic sensitization (odds ratio, 1.49; 95% confidence interval [CI], 1.08­1.89), nasal eosinophilia (odds ratio, 3.2; 95% CI, 1.2­8.8), and eczema (hazard ratio, 1.4; 95% CI, 1.0­2.0), but not with allergic rhinitis, asthma, or blood eosinophilia. Neither leukotriene-C4/D4/E4 nor 11ß-PGF2α was associated with any of the atopic phenotypes. CONCLUSIONS: Eosinophil protein X in urine from asymptomatic neonates is a biomarker significantly associated with later development of allergic sensitization, nasal eosinophilia, and eczema during the first 6 years of life. These findings suggest activation of eosinophil granulocytes early in life before development of atopy-related symptoms.

Asthma attack severity and urinary concentration of eosinophil X protein in children.

OBJECTIVE: Determination of the urinary concentration of eosinophil protein X (U-EPX) may objectively predict the severity and activity of asthma in children. METHODS: Concentrations of U-EPX in 80 non- atopic asthmatic children were compared with those in 25 healthy control children. The patients were studied during attacks and two weeks later. The severity of asthma attacks was determined according to a pre-existing score. U-EPX was measured by the specific radioimmunoassay technique (Pharmacia, Uppsala, Sweden). This measurement was correlated with the clinical and radiological investigations as well as with other variables such as blood oxygen saturation, peak expiratory rate and eosinophil count. RESULTS: U-EPX concentrations were significantly higher in all asthmatic children during attacks (139.6 11.7 microg/mmol of creatinine) than those in the control group (35.3 6.2 microg/mmol of creatinine) (p < 0.001). Two weeks after resolution of the exacerbation, U-EPX significantly decreased (66.5 9.3 microg/mmol of creatinine) (p < 0.001). U-EPX concentrations were highest in patients with severe attacks (191.5 11.3 microg/mmol of creatinine) (p < 0.001). No statistically significant differences were found between mild (88.2 7.2 microg/mmol of creatinine) and moderate attacks (119.6 8.5 microg/mmol of creatinine). At the two-week follow-up, U-EPX concentrations in patients with mild or moderate attacks was similar to those in controls but were persistently elevated in the subgroup with severe attacks (103.8 9.4 microg/mmol of creatinine) (p < 0.001). No significant correlation was found between U-EPX concentrations and blood oxygen saturation, peak expiratory rate or eosinophil count. CONCLUSION: A statistically significant correlation was found between U-EPX concentrations and the severity of attacks in asthmatic children. This substance could be useful in quantifying bronchial inflammation. This result could further be used as a marker of severity of disease exacerbation and would not only facilitate early diagnosis and staging of inflammatory and allergic disorders but would also allow therapy and interventions to be monitored.

High levels of urinary eosinophil protein X in young asthmatic children predict persistent atopic asthma.

Levels of urinary eosinophil protein X (U-EPX) and eosinophil counts were measured in 32 children (12-36 months of age) who were hospitalized for acute asthma, and the U-EPX levels were measured in 20 healthy children of the same age. The ability of these parameters to predict persistent asthma (at least one wheezing episode during the last 6 months) and atopic asthma (a positive skin-prick test [SPT]), was evaluated at a follow-up 2 years later. On admission, levels of U-EPX were higher in children with asthma (median: 120 microg/mmol of creatinine; quartiles: 67-123 microg/mmol of creatinine) than in controls (60 microg/mmol of creatinine, 38-74 microg/mmol of creatinine; p< 0.001). The U-EPX level was higher in those with persistent atopic asthma at follow-up (173 microg/mmol of creatinine, 123-196 microg/mmol of creatinine, n = 16), than in those with persistent non-atopic asthma (73 microg/mmol creatinine, 46-105 microg/mmol of creatinine, n = 8; p< 0.05), and higher than in those with transient asthma (no symptoms at follow-up) (106 microg/mmol creatinine; 42-167 microg/mmol of creatinine, n = 8; p< 0.05). By multiple logistic regression analysis, U-EPX was the only parameter able to predict persistent atopic asthma; eosinophil counts, parental atopy, age or gender could not. Parental atopy was the only parameter predictive for persistent asthma, regardless of atopic status. In conclusion, levels of U-EPX, but not eosinophil counts, measured in young children hospitalized with acute asthma can predict the persistence of atopic asthma 2 years later.

Urinary eosinophil protein X in children: the relationship to asthma and atopy and normal values.

BACKGROUND: In epidemiologic studies, it may be difficult to identify children with bronchial asthma. Since this is the most common chronic respiratory disease in childhood, and its prevalence is still increasing, reliable methods for identification of asthmatic children are required. This study evaluates the use of urinary eosinophil protein X (U-EPX) in epidemiologic studies in identifying atopic and asthmatic children. METHODS: U-EPX was measured in 877 Austrian schoolchildren. The skin prick test (SPT) was performed with eight common aeroallergens, and established questionnaires were used to assess respiratory symptoms. RESULTS: Of our cohort, 2.8% reported physician-diagnosed asthma, 5.1% reported wheezing within the last 12 months, and 24.1% were found to be atopic. In children with physician-diagnosed asthma, as well as in atopic children (positive SPT), median U-EPX levels were significantly higher than in healthy subjects (142.8 and 89.6 vs 63.9 microg/mmol creatinine, P<0.0001 and P<0.0001, respectively). In addition, perennial sensitization to inhalant allergens resulted in higher U-EPX levels than did seasonal sensitization. The odds ratio for U-EPX levels over the 90th percentile was significantly elevated for asthma, for wheezing, for nocturnal cough, and for breathlessness at exercise, as well as for seasonal and perennial sensitization. Pulmonary function was negatively related to U-EPX levels. CONCLUSIONS: Measurement of U-EPX, which can be obtained easily, may be helpful in diagnosing both asthma and atopy in children. However, there is a great overlap between controls and symptomatics, a fact which reduces the sensitivity of U-EPX in determination of the prevalence of asthma in epidemiologic studies.

Lymphocyte subpopulations, cytokines and trace elements in asymptomatic atopic women exposed to an urban environment.

This study evaluates the immune response to exposure to an urban environment from 30 non-atopic and 30 non-symptomatic women with history of respiratory and/or cutaneous allergies. Blood lymphocyte subsets and serum interleukin (IL) 4 and interferon gamma (INF-gamma) of the two groups were similar, while serum IgE and "in vitro" production of IL-4 and INF-gamma by mononuclear blood cells of the atopic women were higher spontaneously or in the presence of PHA, respectively. Blood lead of the nonatopic women (mean 55 microg/l) was positively correlated with CD4+-CD45RO-, CD3+-CD8+ and CD3--HLA-DR+ lymphocyte subsets, while urinary trans-trans muconic acid (a metabolite of benzene) of both groups of women (mean about 50 microg/l) was significantly correlated with NK CD16+CD56+ lymphocytes. Urine chromium of the non-atopic subjects was significantly correlated with activated T, B and NK HLA-DR+ cells. Urine nickel of both groups of women was correlated with CD4+-CD45RO+ "memory" lymphocytes and their ratio with CD4+-CD45RO- "virgin" lymphocytes suggesting that the metal enhances maturation of "virgin" into "memory" lymphocytes. On the whole, this study demonstrates that exposure to low levels of toxic agents, produced by vehicular traffic in an urban environment, exerts effects on immune functions of women.

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.

Urinary excretion of leukotriene E4 and 11-dehydrothromboxane B2 in patients with spontaneous asthma attacks.

BACKGROUND: Cysteinyl leukotrienes (LTs) and thromboxane A2 (TXA2) are known to play an essential role in the pathogenesis of atopic asthma. However, their role in nonatopic asthma has not as yet been clarified. The objectives of this study were to define (1) the participation of LTs and TXA2 in nonatopic asthma and (2) the relationship between LTs and TXA2 in asthma attacks. METHODS: Urinary excretion of leukotriene E4 (LTE4) and 11-dehydrothromboxane B2 (11DTXB2) was measured in 10 atopic and 10 nonatopic asthmatics who were admitted to hospital with either an acute asthma attack or status asthmaticus. RESULTS: In atopic asthmatics, urinary excretion of LTE4 and 11DTXB2 was significantly higher on admission with an asthma attack, and returned to control levels when the patients were in the improved state (179+/-29 to 65+/-16 ng/day in LTE4, 1,085+/-250 to 440+/-90 ng/day in 11DTXB2). Similar findings were observed in nonatopic asthmatics (148+/-13 to 61+/-11 ng/day in LTE4, 1,089+/-206 to 457+/-60 ng/day in 11DTXB2). However, when the individual data during the attack were analyzed, there was no correlation between urinary excretion of LTE4 and that of 11DTXB2 in both types of asthma. CONCLUSION: Both LTs and TXA2 may be implicated in the pathogenesis of the nonatopic as well as the atopic type of asthma, but no correlation between these two metabolites was observed in the individuals.

[Importance of urinary methylhistamine measurements during allergy provocation tests]. / Intérêt du dosage de la méthylhistamine urinaire au cours des tests de provocation en allergie.

Methylhistamine, histamine's metabolite, was measured in urine by radio-immuno-assay in 79 provocation test. Six of them were positive with clinical symptoms. All of the six were associated with a significant increase of urinary methylhistamine (UMH). Therefore, there is a good correlation between positive provocation tests and increase of UMH level. In these cases, the severity of clinical symptoms is related to the increase of U.M.H.

Diurnal variation of urinary histamine and 1-methylhistamine excretion in healthy children.

In order to establish a noninvasive method of monitoring immediate hypersensitivity reactions in children, we studied the diurnal variation of urinary histamine and 1-methylhistamine excretion and the influence of food intake in a group of 14 healthy nonatopic children (aged 2-16 years). Histamine and 1-methylhistamine in spontaneous urine samples were determined by radioimmunoassay. Mean variation of 2-h intervals was much higher for urinary histamine than for 1-methylhistamine (45% of base-line level versus 24%). There was no circadian rhythm or influence of food intake. The short half-life of histamine released into blood circulation may be the main reason for the higher variation of histamine excretion. In children, urinary 1-methylhistamine is less influenced by diurnal variation and is therefore more suited to monitor immediate hypersensitivity reactions than urinary histamine itself.

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)

Determination of N-methylhistamine in urine as an indicator of histamine release in immediate allergic reactions.

The use of the urine histamine metabolite, N-methylhistamine (N-MH), as a parameter of histamine release in immediate allergic reactions was investigated. Baseline levels were determined in 34 normal control subjects and 29 atopic patients. Increases of urine N-MH values were measured during histamine infusions and in venom-allergic patients receiving bee-sting challenges. N-MH was determined by a newly developed radioimmunoassay. Baseline levels in control subjects and atopic patients demonstrated no significant differences. With regard to challenge tests, fluctuation of N-MH levels during a 6-hour period was measured. Random 6-hour increases in healthy and atopic subjects ranged from 5% to 41%. Before infusion of histamine (0.25 micrograms/kg/min for 30 minutes), baseline values were 137 +/- 11.4 micrograms N-MH per gram of creatinine and 9 +/- 1.1 micrograms N-MH per hour (n = 9). Levels peaked 1 hour after infusion at 275 +/- 45 micrograms/gm of creatinine and 44 +/- 5.6 micrograms/hr and decreased to resting levels after 2 hours. Metabolization by N-MH accounted for 9.5% +/- 4.9% (range, 2.4% to 18.4%) of infused histamine in the urine of the nine subjects. Bee-sting challenges were performed in 12 patients and three control subjects. Only in three patients experiencing generalized urticaria, nausea, dyspnea, and hypotension were significant increases of urine N-MH levels (138%, 144%, and 238%) observed. All other patients and three normal control subjects demonstrated normal local reactions without increase of N-MH values.(ABSTRACT TRUNCATED AT 250 WORDS)