Ozone exposure,vitamin C intake,and genetic susceptibility of asthmatic children in Mexico City: a cohort study

Background

We previously reported that asthmatic children with GSTM1 null genotype may be more susceptible to the acute effect of ozone on the small airways and might benefit from antioxidant supplementation. This study aims to assess the acute effect of ozone on lung function (FEF_25-75) in asthmatic children according to dietary intake of vitamin C and the number of putative risk alleles in three antioxidant genes: GSTM1, GSTP1 (rs1695), and NQO1 (rs1800566).

Methods

257 asthmatic children from two cohort studies conducted in Mexico City were included. Stratified linear mixed models with random intercepts and random slopes on ozone were used. Potential confounding by ethnicity was assessed. Analyses were conducted under single gene and genotype score approaches.

Results

The change in FEF_25-75 per interquartile range (60 ppb) of ozone in persistent asthmatic children with low vitamin C intake and GSTM1 null was −91.2 ml/s (p = 0.06). Persistent asthmatic children with 4 to 6 risk alleles and low vitamin C intake showed an average decrement in FEF_25-75 of 97.2 ml/s per 60 ppb of ozone (p = 0.03). In contrast in children with 1 to 3 risk alleles, acute effects of ozone on FEF_25-75 did not differ by vitamin C intake.

Conclusions

Our results provide further evidence that asthmatic children predicted to have compromised antioxidant defense by virtue of genetic susceptibility combined with deficient antioxidant intake may be at increased risk of adverse effects of ozone on pulmonary function.     

儿童哮喘与肺炎支原体感染关系的探讨

目的:探讨儿童哮喘发作与肺炎支原体(MP)感染之间的关系,并分析合并MP感染的患儿的临床表现。方法:将79例2-14岁急性哮喘发作的患儿依据病史分做两组:第一次哮喘发作的35人(始发哮喘组),已经有哮喘病史的44人(复发哮喘组)。采用被动冷凝集法检测两组患儿肺炎支原体抗体(MP-IgM)。结果:始发哮喘组和复发哮喘组分别有16例(45.7%)和10例(22.7%)患儿MP-IgM阳性(P0.05)。始发哮喘组与复发哮喘组MP-IgM阳性的患儿发热和肺部啰音发生率明显高于MP-IgM阴性的患儿(P0.05),血清IgE水平也明显高于MP-IgM阴性的患儿(P0.05)。结论:MP感染与儿童哮喘发作关系密切,合并MP感染的哮喘患儿发热或肺部啰音发生率明显高于未合并MP感染的哮喘患儿。     

5岁以下哮喘患儿血清过敏原病例对照研究及相关性分析

摘要 目的：探讨5岁以下哮喘儿童与血清特异性过敏原（specific IgE,sIgE）的分布情况。方法：本研究采用免疫印迹法对 2019 年1月至 2019 年12月在西安交通大学第二附属医院住院的5岁以下62例哮喘患儿和49例喘息患儿的行血清特异性过敏原检测,对比分析5岁以下哮喘和喘息儿童过敏原分布情况及与哮喘的发病关系。结果：户尘螨、猫毛皮屑、狗毛皮屑、蒿草、葎草、桤杨柳山毛榉橡胡桃、烟曲霉、念珠菌点青霉分枝孢霉交链孢霉黑曲霉吸入过敏原和花生黄豆、腰果开心果榛子杏仁核桃、虾蟹、桃苹果芒果荔枝草莓食物过敏原这12类过敏原在哮喘组与喘息组有显著差异（P<0.05）,与哮喘发病有关。多因素logistic回归分析结果显示户尘螨、猫毛皮屑、坚果类、霉菌、水果类是哮喘发病的危险因素（P<0.05）。户尘螨、猫毛皮屑和虾蟹是男性哮喘患儿发病的危险因素,念珠菌点青霉分枝孢霉交链孢霉黑曲霉是女性哮喘患儿发病的危险因素（P<0.05）。结论：血清特异性（sIgE）过敏原在哮喘与喘息患儿中分布不同,同时发现过敏原在哮喘患儿中存在性别差异,故对哮喘患儿进行过敏性检测可以作为回避过敏原的依据。     

Epidermal Growth Factor Removal or Tyrphostin AG1478 Treatment Reduces Goblet Cells & Mucus Secretion of Epithelial Cells from Asthmatic Children Using the Air-Liquid Interface Model

Rationale

Epithelial remodelling in asthma is characterised by goblet cell hyperplasia and mucus hypersecretion for which no therapies exist. Differentiated bronchial air-liquid interface cultures from asthmatic children display high goblet cell numbers. Epidermal growth factor and its receptor have been implicated in goblet cell hyperplasia.

Objectives

We hypothesised that EGF removal or tyrphostin AG1478 treatment of differentiating air-liquid interface cultures from asthmatic children would result in a reduction of epithelial goblet cells and mucus secretion.

Methods

In Aim 1 primary bronchial epithelial cells from non-asthmatic (n = 5) and asthmatic (n = 5) children were differentiated under EGF-positive (10ng/ml EGF) and EGF-negative culture conditions for 28 days. In Aim 2, cultures from a further group of asthmatic children (n = 5) were grown under tyrphostin AG1478, a tyrosine kinase inhibitor, conditions. All cultures were analysed for epithelial resistance, markers of differentiation using immunocytochemistry, ELISA for MUC5AC mucin secretion and qPCR for MUC5AC mRNA.

Results

In cultures from asthmatic children the goblet cell number was reduced in the EGF negative group (p = 0.01). Tyrphostin AG1478 treatment of cultures from asthmatic children had significant reductions in goblet cells at 0.2μg/ml (p = 0.03) and 2μg/ml (p = 0.003) as well as mucus secretion at 2μg/ml (p = 0.04).

Conclusions

We have shown in this preliminary study that through EGF removal and tyrphostin AG1478 treatment the goblet cell number and mucus hypersecretion in differentiating air-liquid interface cultures from asthmatic children is significantly reduced. This further highlights the epidermal growth factor receptor as a potential therapeutic target to inhibit goblet cell hyperplasia and mucus hypersecretion in asthma.     

Growth Hormone Secretion in Growth-retarded Asthmatic Children

The serum growth hormone response to Bovril was studied in 12 growth-retarded children with severe asthma, and was found to be normal. Eight children who were receiving corticosteroids had been small for their age before starting steroid treatment. It is concluded that there is no case for treating growth-retarded asthmatic children with growth hormone.     

Is childhood asthma being underdiagnosed and undertreated?

Thirty-four cases of asthma in children referred to outpatient clinics in Newcastle upon Tyne (16 cases) and London (18 cases) were reviewed. In both cities there was evidence of inappropriate diagnosis and treatment by general practitioners. One of the main factors seemed to be doctors'' reluctance to use the word "asthma," even when a history of episodic wheezing strongly suggested the diagnosis. Freer use of the word "asthma" might help parents to co-operate in managing asthmatic children and allow them to be better prepared to cope with severe asthmatic attacks if they occur.     

Flow cytometrical determination of regulatory cytokines (IL-10, IL-12) and circulating dendritic cell cytokines in allergic asthmatic children

Interleukin (IL)-10 and IL-12 have been suggested to be key regulators in the pathogenesis of allergic asthma. Several of the secretion products of dendritic cells (DC), such as IL-12, IL-10, IL-1beta and TNF-alpha, are considered to play a role in allergic asthma. This study compares the production of IL-10 and IL-12 in allergic asthmatic children (n = 17) and controls (n = 14) by measuring their extracellular secretion in whole blood samples after stimulation, using a microsphere-based immunoassay. Additionally, we assessed intracellular production of IL-1beta, TNF-alpha, IL-12 and IL-10 by circulating DC in stimulated whole blood samples of asthmatic and healthy children. The concentration of IL-10 in the supernatants of LPS-stimulated whole blood was significantly lower in allergic asthmatic children as compared to healthy children (463 (207-768) vs 881 (364-2626) pg/mL; p = 0.005). When a combined LPS and IFN-gamma stimulation was used, IL-10 production decreased significantly as compared to LPS alone, especially in healthy children. Consequently, no difference in IL-10 production after LPS/IFN-gamma stimulation was found between healthy and allergic children. In contrast to isolated LPS stimulation, stimulation with LPS/IFN-gamma induced higher IL-12 production; allergic asthmatic children showed a significantly lower IL-12 secretion after LPS/IFN-gamma stimulation as compared to healthy children (20 (5-247) vs 208 (7-775) pg/mL; p=0.03). Moreover, the number of IL-12 producing CD11c-positive DC (DC1) tended to be lower in asthmatic children compared to healthy children (0.05 (0.00-0.45) vs 0.27 (0.00-0.83) 10(6)/L) and correlated with the extracellular release of IL-12 in asthmatic children (r = 0.65; p = 0.016). The number of IL-1beta and TNF-alpha producing CD11c-positive DC (DC1) was comparable between healthy and asthmatic children. We hypothesize that the decreased production of IL-10 and IL-12 is responsible for Th2 polarized responses in allergic asthmatic children.     

136例急性呼吸道感染患儿病原菌特点及鼻咽分泌物中呼吸道合胞病毒和人偏肺病毒基因分析

目的 分析136例急性呼吸道感染患儿的病原菌特点,并对患儿鼻咽分泌物中呼吸道合胞病毒(RSV)、人偏肺病毒(hMPV)进行检测,为后续研究提供参考。 方法 选择2017年1月至2019年4月我院收治的136例急性呼吸道感染患儿为研究对象,分析患儿呼吸道感染病原菌分布、耐药性,并对不同性别、年龄和感染部位患儿鼻咽分泌物中hMPV和RSV基因进行检测。 结果 136例急性呼吸道感染患儿共检出病原菌164株,其中革兰阴性菌占70.73%(116/164),革兰阳性菌占25.00%(41/164),真菌占4.27%(7/164);以铜绿假单胞菌(26.22%)、肺炎克雷伯菌(17.07%)、大肠埃希菌(15.24%)、金黄色葡萄球菌(12.20%)为主。药敏试验显示,铜绿假单胞菌、肺炎克雷伯菌、大肠埃希菌均对哌拉西林/他唑巴坦、头孢哌哃/舒巴坦、亚胺培南、左氧氟沙星、阿米卡星的耐药性较低(耐药率0.05)。1~2岁患儿hMPV检出率最高,0~5岁患儿RSV检出率较高。喘息性支气管炎、毛细支气管炎患儿hMPV检出率均较高,支气管肺炎、毛细支气管炎患儿RSV检出率均较高。 结论 急性呼吸道感染患儿病原菌以革兰阴性菌为主,应结合病原菌的药敏试验结果为患儿选择更有针对性的药物进行治疗。此外,应重视患儿RSV、hMPV感染情况,采取科学有效的方式对急性呼吸道感染进行预防和治疗。     

哮喘患儿口咽部菌群分析及3株优势菌的拮抗作用

了解哮喘患儿呼吸道菌群多样性及其组成特征, 同时研究所分离的3株优势菌对流感嗜血杆菌的抑制作用, 探究哮喘与呼吸道菌群之间的关系。

采集沈阳市儿童医院呼吸内科2019年3月至2019年12月收治的21例4~12岁急性发作期哮喘患儿咽拭标本, 并同时采集23例同龄健康儿童的咽拭标本作为对照, 对呼吸道菌群进行分离培养、纯化和16S rRNA鉴定。采用牛津杯法检测健康儿童口咽部分离的3株优势菌对流感嗜血杆菌的拮抗作用。

哮喘和健康儿童呼吸道培养出的需氧菌(t=2.143, P=0.038)和厌氧菌(t=3.270, P=0.002)的密度差异有统计学意义。哮喘患儿咽部需氧菌以肺炎链球菌和流感嗜血杆菌为主, 厌氧菌以韦荣球菌为主。健康儿童咽部需氧菌以缓症链球菌和口腔链球菌为主, 厌氧菌以干酪乳杆菌为主。健康儿童口咽部的3株优势菌对哮喘儿童口咽部流感嗜血杆菌的生长具有显著抑制作用。

与健康儿童相比, 哮喘患儿口咽部菌群发生紊乱, 且哮喘患儿口咽部需氧菌、厌氧菌密度显著增加。健康儿童口咽部的某些优势菌可能对哮喘致病菌的定植有一定的拮抗作用。

     

Liquid chromatography/mass spectrometry analysis of exhaled leukotriene B4 in asthmatic children

Background

The role of leukotriene (LT) B₄, a potent inflammatory mediator, in atopic asthmatic and atopic nonasthmatic children is largely unknown. The lack of a gold standard technique for measuring LTB₄ in exhaled breath condensate (EBC) has hampered its quantitative assessment in this biological fluid. We sought to measure LTB₄ in EBC in atopic asthmatic children and atopic nonasthmatic children. Exhaled nitric oxide (NO) was measured as an independent marker of airway inflammation.

Methods

Fifteen healthy children, 20 atopic nonasthmatic children, 25 steroid-naïve atopic asthmatic children, and 22 atopic asthmatic children receiving inhaled corticosteroids were studied. The study design was of cross-sectional type. Exhaled LTB₄ concentrations were measured using liquid chromatography/mass spectrometry-mass spectrometry (LC/MS/MS) with a triple quadrupole mass spectrometer. Exhaled NO was measured by chemiluminescence with a single breath on-line method. LTB₄ values were expressed as the total amount (in pg) of eicosanoid expired in the 15-minute breath test. Kruskal-Wallis test was used to compare groups.

Results

Compared with healthy children [87.5 (82.5–102.5) pg, median and interquartile range], exhaled LTB₄ was increased in steroid-naïve atopic asthmatic [255.1 (175.0–314.7) pg, p < 0.001], but not in atopic nonasthmatic children [96.5 (87.3–102.5) pg, p = 0.59)]. Asthmatic children who were receiving inhaled corticosteroids had lower concentrations of exhaled LTB₄ than steroid-naïve asthmatics [125.0 (25.0–245.0) pg vs 255.1 (175.0–314.7) pg, p < 0.01, respectively]. Exhaled NO was higher in atopic nonasthmatic children [16.2 (13.5–22.4) ppb, p < 0.05] and, to a greater extent, in atopic steroid-naïve asthmatic children [37.0 (31.7–57.6) ppb, p < 0.001] than in healthy children [8.3 (6.1–9.9) ppb]. Compared with steroid-naïve asthmatic children, exhaled NO levels were reduced in asthmatic children who were receiving inhaled corticosteroids [15.9 (11.5–31.7) ppb, p < 0.01].

Conclusion

In contrast to exhaled NO concentrations, exhaled LTB₄ values are selectively elevated in steroid-naïve atopic asthmatic children, but not in atopic nonasthmatic children. Although placebo control studies are warranted, inhaled corticosteroids seem to reduce exhaled LTB₄ in asthmatic children. LC/MS/MS analysis of exhaled LTB₄ might provide a non-invasive, sensitive, and quantitative method for airway inflammation assessment in asthmatic children.     

Association between childhood atopic disease and parental atopic disease in a population with high consanguinity

The aim of the study was to investigate the association between asthma, allergic rhinitis, and eczema in Qatari schoolchildren with allergic conditions in their parents. A cross-sectional study was conducted among 3500 Qatari schoolchildren aged 6-14 years in period: February, 2003-February, 2004. A questionnaire was used to collect the clinical history of asthma and allergic rhinitis in their parents and siblings. It was found that 21.6% of asthmatic children had mothers with asthma and 18.2% fathers with asthma. This contrasted with 6.8% of non-asthmatic children who had fathers with asthma and 9.4% mothers with asthma. As for allergic rhinitis, 26.5% of asthmatic children had mothers with allergic rhinitis and 25.3% fathers with allergic rhinitis. The frequency of either parent of the asthmatic children having allergic rhinitis was 41.8% and for both parents was 10.0%. The frequency of siblings having asthma was 36.6%, allergic rhinitis 16.4%, and eczema 29.1%. The present study revealed a strong association between respiratory allergies and eczema in parents, and their asthmatic children.     

哮喘儿童父母知识知晓率、用药依从性及影响因素分析

目的:了解哮喘儿童父母的对疾病知识的掌握情况以及儿童的服药依从情况和影响因素,为提高哮喘儿童的控制率提供参考依据。方法:选择2015年1月-2015年12月于上海市第十人民医院儿科门诊诊治的支气管哮喘儿童93例,调查其哮喘控制情况、哮喘服药依从性和父母基本情况与相关知识。依从性与知识知晓率的比较采用双向有序的检验,影响因素采用有序结果的累积优势Logistic回归分析。结果:本次调查93例哮喘儿童中,哮喘完全控制率为23.7%,儿童服药依从性好的比率为25.8%,哮喘儿童父母相关知识知晓率高的比率为25.8%,儿童哮喘控制率与服药依从性之间存在相关性(P=0.029),哮喘儿童服药依从性与哮喘儿童父母相关知识知晓率之间存在相关性(P=0.035)。哮喘儿童的服药依从性受到儿童性别(OR=1.153,95%CI:1.04-1.96)、家族史(OR=1.402,95%CI:1.20-2.33)、知识知晓率(OR=1.828,95%CI:1.05-3.17)和病程(OR=0.758,95%CI:0.35-0.97)等因素的影响(P0.05)。结论:哮喘儿童的服药依从性受到儿童性别、家族史、知识知晓率和病程等因素的影响,要充分发挥儿童父母的作用,从医院内干预逐渐进入家庭干预,通过对父母或者监护人的认知或用药知识的提高,切实提高哮喘儿童的用药依从性和哮喘的控制率。     

Galectin-7在哮喘儿童支气管黏膜中的表达及对支气管上皮细胞凋亡的影响

目的:探讨半乳糖凝集素-7(Galectin-7)在哮喘儿童支气管黏膜中的表达及对支气管上皮细胞凋亡的影响。方法:收集哮喘儿童支气管黏膜及支气管扩张非哮喘儿童支气管黏膜,Western blot检测其Galectin-7的表达。体外培养人支气管上皮细胞,分为正常组、对照组、感染组和实验组,正常组用正常的人支气管上皮细胞,对照组细胞用转染siRNA control后的人支气管上皮细胞,感染组细胞用RSV感染后的人支气管上皮细胞,实验组细胞为RSV感染后并转染siRNA Galectin-7的人支气管上皮细胞。培养24 h后,检测各组细胞中Galectin-7蛋白表达,并采用流式细胞术检测各组细胞的凋亡情况,Western blot检测细胞中Bcl-2、Bax、STAT3、p-STAT3蛋白的表达。结果:哮喘儿童支气管黏膜中Galectin-7的表达明显高于非哮喘儿童支气管黏膜组织(P0.01)。正常组和对照组Galectin-7水平比较差异无统计学意义(P0.05),感染组Galectin-7、Bax表达和细胞凋亡率均明显高于正常组,而Bcl-2、p-STAT3的表达均明显低于正常组(P0.01),实验组Galectin-7、Bax表达和细胞凋亡率明显低于感染组,而Bcl-2、p-STAT3的表达均明显高于感染组(P0.01)。结论:Galectin-7在哮喘儿童支气管黏膜中表达上调,可能通过活化STAT3,促进支气管上皮细胞凋亡。     

呼出气一氧化氮浓度与儿童哮喘病情控制及不同哮喘亚型的相关性研究

目的:探讨呼出气一氧化氮(FeNO)浓度与儿童哮喘病情控制及不同哮喘亚型的相关性。方法:选取2017年1月至2018年1月期间于我院确诊为支气管哮喘及毛细支气管炎的患儿各60例,分别设为哮喘组与毛细支气管炎组,另选取同期于我院进行体检的健康儿童40例作为对照组。哮喘组与毛细支气管炎组分别在治疗前、治疗后1 h及治疗后4周测定FeNO,对照组在体检时测定FeNO。对比对照组体检时以及哮喘组、毛细支气管炎组患儿不同治疗时期的FeNO浓度变化;哮喘组患儿根据不同病情控制情况分为哮喘控制组、哮喘部分控制组与哮喘未控制组,根据不同哮喘亚型分为咳嗽变异性组与非咳嗽变异性组,分析FeNO与哮喘患儿疾病控制情况、哮喘亚型的相关性。结果:哮喘组治疗前的FeNO浓度高于毛细支气管炎组治疗前和对照组体检时的FeNO浓度(P0.05);与治疗前与治疗后1 h比较,治疗4周后哮喘组与毛细支气管炎组患儿FeNO浓度降低(P0.05),治疗后1 h及治疗4周后哮喘组FeNO浓度高于毛细支气管炎组(P0.05)。哮喘控制组FeNO浓度低于部分控制组与哮喘未控制组,哮喘部分控制组FeNO浓度低于哮喘未控制组,咳嗽变异性组FeNO浓度高于非咳嗽变异性组(P0.05)。FeNO浓度与病情控制呈负相关,FeNO浓度越低,病情控制程度越好(r=-0.512,P=0.034)。结论:哮喘患儿的FeNO浓度高于毛细支气管炎患儿、健康儿童,且与患儿哮喘的病情控制存在相关性,可作为哮喘患儿的辅助诊断指标。     

Response of Leucocyte Adenyl Cyclase to Isoprenaline and Effect of Alpha-blocking Drugs in Extrinsic Bronchial Asthma

The finding by several workers that biochemical responses to catecholamines are diminished in asthmatic patients during periods of active asthma as compared to normal subjects has led to the recognition of the beta-adrenergic blockade phenomenon, a common accompaniment of extrinsic bronchial asthma. Using an intact cell method to measure leucocyte adenyl cyclase activity, we have been able to show that there is a noticeably reduced responsiveness of this enzyme system (which is now identified with beta-receptor function) to isoprenaline in the leucocytes of patients suffering from acute bronchial asthma, but that asthmatic patients in remission could not be distinguished from normal persons in this respect. Evidently the defective beta-receptor function may be associated with overactivity of the alpha-receptors in acute bronchial asthma, since the responsiveness to isoprenaline stimulation could be restored towards normal by concomitant treatment of the leucocytes of these patients with alpha-receptor blocking drugs such as phentolamine or thymoxamine. Ouabain, though somewhat less potent, also enhanced responsiveness to isoprenaline stimulation. The relation of these results to the clinical observation of adrenaline resistance in active asthma suggests that alpha-receptor blocking drugs may be of value in restoring the sensitivity of beta-receptors to sympathomimetic amines.     

Spectrum of Asthma in Children—III,Psychological and Social Components

Behavioural disturbances in the child, the mother-child and family relationships, and the family social structure were studied in a representative sample of the whole range of asthmatic children and compared with a control group of normal children. Behavioural disturbances occurred more often and at a statistically significant level only in the small group of children with severe and continuing asthma. These children were those with severe chronic airways obstruction as assessed physiologically and also with the most severe allergic manifestations.Predominant in the mother-child relations was an over-concern to protect the child''s health in those children with continuing asthma at 14 years of age. The families of the very severely affected group of children showed evidence of more stress than other families. Socioeconomic conditions were not significantly different in any group of asthmatic children compared with the control group.     

Endocrine Response to Substitution of Corticotrophin for Oral Prednisolone in Asthmatic Children

The hypothalamo-pituitary-adrenal axis has been assessed in 17 asthmatic children before and after long-term prednisolone therapy was changed to daily corticotrophin. In 14 of the 17 children the plasma corticosteroid concentration exceeded 15 μg/100 ml within five days of starting corticotrophin. No exacerbation of asthmatic symptoms occurred during conversion. The plasma corticosteroid response to insulin-induced hypoglycaemia was normal in four children about six weeks after conversion to corticotrophin, took up to 36 months to become normal in nine, and remained abnormal in one child throughout the period of the trial.     

Combined treatment with sustained-release theophylline and beta2-adrenoceptor-stimulating agents in chronic childhood asthma.

The effect of adding theophylline to treatment with a beta2-adrenoceptor stimulant was studied in 18 asthmatic children in a double-blind cross-over trial. Most patients were taking cromolyn sodium (cromoglycic acid) or beclomethasone aerosol, or both. A sustained-release preparation of theophylline was administered in individually titrated doses, producing a mean plasma theophylline concentration of about 8 micrograms/ml. Statistically significant improvements were found during the theophylline treatment in symptom score, consumption of beta2 stimulants in aerosol form, and morning peak expiratory flow rate and forced expiratory volume in one second. There was also a reduced need for emergency-room treatment during the theophylline period. Reported side effects were few and mild and were similar during the theophylline and placebo periods. Of the 17 patients who completed the trial, 14 preferred theophylline and three expressed no preference between theophylline and placebo. Adding submaximal doses of sustained-release theophylline to treatment with a beta2 stimulant gave further relief of asthmatic symptoms without appreciable side effects, suggesting that the drug combination has a favourable therapeutic index.     

Effects of systemic glucocorticosteroids on peripheral neutrophil functions in asthmatic subjects: an ex vivo study

In 21 asthmatic subjects, several functions of isolated peripheral neutrophils (chemokinesis and chemotaxis toward 10% E. coli; superoxide anion generation after PMA; leukotriene B(4) (LTB(4)) release from whole blood and isolated neutrophtls, before and after different stimuli) were evaluated during an acute exacerbation of asthma, and after 14 - 54 days of treatment with systemic glucocorticosteroids (GCS). During acute exacerbation, superoxide anion generation was higher in asthmatics than in eleven normal subjects (39.2 +/- 14.1 vs. 25.2 +/- 7.3 nmol, p < 0.05); there was a significant correlation between FEV(1) (% of predicted) and neutrophil chemotaxis (r = -0.52, p = 0.04). After treatment, there was no significant change in all neutrophil functions, except for a decrease in neutrophil chemotaxis in subjects who showed an FEV(1) increase > 20% after GCS treatment (from 131 +/- 18 to 117 +/- 21 mum, p = 0.005). Chemokinesis sicantly decreased in all subjects, and the changes significantly correlated with an arbitrary score of the total administered dose of GCS (r = 0.57, p < 0.05). These data suggest that neutrophil activation plays a minor role in asthma, and that treatment with GCS is not able to modify most functions of peripheral neutrophils in asthmatic subjects; chemotaxis seems to be related only to the severity of the asthma and it could reflect the improvement of the disease.