哮喘患儿家庭内尘螨过敏原分布特征及其临床意义

目的了解北京地区尘螨过敏性哮喘患儿家庭环境内尘螨过敏原含量分布特征,初步探讨尘螨过敏原暴露水平的临床意义。方法选取54例尘螨过敏性哮喘患儿,其中男性37例,女性17例;年龄3～16岁,平均年龄8岁2个月。采集患儿家庭中床垫、枕头、卧室地板、客厅地板及沙发的灰尘,采用酶联免疫吸附分析（ELISA）测定以上灰尘样本中户尘螨1组过敏原（Der p1）和粉尘螨1组过敏原（Der f1）的含量;应用荧光ELISA测定患儿血清尘螨特异性IgE浓度;评估患儿哮喘临床控制情况,应用化学发光法测定患儿呼出气一氧化氮浓度（FeNO）。结果采集灰尘样本255份,以中位数（最小值～最大值）表示尘螨过敏原含量,床垫、枕头和沙发灰尘样本中Derf1和Derp1的含量显著高于卧室地板和客厅地板灰尘样本中尘螨过敏原含量。Derf1平均含量为0.13μg/g,显著高于Derp1平均含量0.02μg/g（P〈0.05）。Derp1和Derf1联合暴露的最高含量平均为2.18（0.07～54.59）μg/g。Der p1和Der f1联合最高暴露含量≥10.00μg/g、2.00～10.00μg/g、0.05～2.00μg/g的例数分别为4例（7.4%）、24例（44.4%）、26例（48.1%）。其中未控制组患儿家庭内尘螨过敏原最高暴露水平为27.41（0.23～54.59）μg/g,均显著高于部分控制组和控制组哮喘患儿尘螨过敏原最高暴露水平1.66（0.07～26.27）μg/g、2.90（0.37～33.75）μg/g（P〈0.05）。不同sIgE浓度分级组间尘螨过敏原最高暴露水平的差异、不同FeNO浓度范围组间尘螨过敏原最高暴露水平差异均无统计学意义。结论北京地区尘螨过敏性哮喘患儿家庭尘螨以Der f1为主,床垫、枕头及沙发灰尘样本是Der p1和Der f1的主要来源;哮喘未控制者的尘螨过敏原最高暴露水平明显增高。     

婴幼儿和儿童哮喘过敏原IgE 检测及临床意义

目的:研究婴幼儿和儿童血清特异性Ig E过敏原检测在哮喘中的临床意义。方法:选取2011年11月至2016年12月就诊的505例单纯哮喘婴幼儿和儿童(n=385)及非过敏患儿(n=120),采用德国FOOKE全自动酶免疫分析系统对过敏原特异性Ig E抗体进行检测,分别建立不同性别、年龄的单纯性哮喘组与非过敏对照组,对过敏原与哮喘进行多因素Logistic回归分析。结果:505例婴幼儿和儿童血清Ig E过敏原检测阳性者240例(47. 5%)。婴幼儿和儿童哮喘过敏原分布单因素分析结果显示,户尘螨、霉菌类、屋尘、牛奶、猫/狗毛皮屑、混合草等与哮喘发生有相关性(P0. 05)。而多因素分析结果显示,户尘螨、霉菌类、屋尘螨是发病的危险因素(P0. 05);不同年龄组婴幼儿和儿童单因素分析结果显示,在3岁婴幼儿仅屋尘螨与哮喘发生有相关性(P0. 05),在3～14岁患儿中户尘螨、屋尘螨与哮喘发生有相关性(P0. 05),在7～14岁患儿中霉菌与哮喘发生有相关性(P0. 05);户尘螨、屋尘螨是男、女性婴幼儿和儿童哮喘发生的危险因素(P0. 05),而霉菌、腰果/花生是男性婴幼儿和儿童哮喘发生的危险因素(P0. 05)。结论:婴幼儿和儿童哮喘以户尘螨、屋尘螨、霉菌类过敏原为主,血清过敏原检测对早期评估婴幼儿和儿童哮喘的发生、发展有重要意义。     

特异性免疫治疗对哮喘和鼻炎患者血清炎性细胞因子的影响

目的通过检测对屋尘螨过敏的的哮喘和/或鼻炎患者在特异性免疫治疗或常规药物治疗过程中血清白介素(IL)-5、IL-10、IL-17、INF-γ及TNF-α等5种细胞因子的水平,探讨特异性免疫治疗对过敏性哮喘和鼻炎患者血清炎性细胞因子的影响。方法选取44例在广州呼吸疾病研究所接受标准化屋尘螨特异性免疫治疗(SIT)满1年的哮喘和/或鼻炎患者作为SIT组,50例对屋尘螨过敏并未接受SIT治疗的哮喘和/或鼻炎患者作为病例组,另外选取23例无过敏、无哮喘与鼻炎的健康自愿者作为对照组,用悬浮芯片方法检测三组人群血清中IL-5、IL-10、IL-17、INF-γ及TNF-α等5种细胞因子的水平。结果服从正态分布的数据以均数±标准差表示,偏态分布的数据以中位数(四分位间距数)表示。FEV1%(%)在SIT组、病例组及对照组中分别为93.05±15.62、87.0±13.51、95.51±7.84,三组比较显示无显著差异(P>0.05);AHR在这三组中分别为2(0,3)、1(0,2)、0(0,0),三组比较显示SIT组及病例组均显著高于对照组(P<0.05),SIT组与病例组比较无显著差异(P>0.05);血清IL-5(pg/mL)在SIT组、病例组及对照组中的水平分别为1.46(0.62,2.71)、1.95(1.18,2.46)、0.34(0.01,0.83),其中SIT组显著低于病例组(P=0.001),病例组显著低于对照组(P<0.001);IL-10(pg/ml)在SIT组、病例组及对照组中的水平分别为1.6(0.95,2.69)、1.25(0.93,1.8)、0.43(0.21,1.07),SIT组与病例组显著高于对照组(P<0.001);TNF-α(pg/mL)在SIT组、病例组及对照组中的水平分别为10.81(2.18,31.3)、3.39(1.78,6.83)、0.09(0.09,1.18),其中SIT组显著高于病例组与对照组(P=0.004),病例组又显著高于对照组(P<0.001)。IL-17与INF-γ在三组受试者的血清中均不可测出。结论哮喘和鼻炎患者血清中IL-5、TNF-α水平显著高于正常人,说明IL-5和TNF-α在哮喘和/或鼻炎的致病中发挥重要作用;关于SIT对炎性细胞因子的影响还有待我们进一步的研究。     

屋尘螨变应原重组体免疫治疗的实验研究

目的：建立屋尘螨哮喘动物模型，比较分别用屋尘螨粗浸液、重组Derp2（rDerp2）进行免疫治疗的疗效，为变态反应性疾病的免疫治疗提供新的思路。方法：近交系清洁级BALB／c小鼠，腹膜内注射（i．p．）屋尘螨变应原粗浸液与灿（OH）3生理盐水的混悬液致敏小鼠，建立哮喘模型；治疗组在致敏后分别给予i．p．屋尘螨粗浸液、rDerp2溶液进行免疫治疗后，鼻腔滴入（i．n．）屋尘螨粗浸液予以激发；阴性对照组从致敏，阳性对照组在致敏后，均同步生理盐水处理。用ELISA方法检测各组实验动物血清中IgE、IgG1、IgG2a的水平，以及支气管肺泡灌洗液（BALF）与脾细胞培养后上清液（SCCS）中细胞因子IL-4、IFN-γ水平，计数BALF中细胞总数与分类细胞数，并制备肺组织病理切片以观察其病理改变。结果：添加铝佐剂的屋尘螨变应原致敏的小鼠在特异性变应原的连续激发下，肺组织产生明显的炎症反应，表现为BALF中细胞总数增加以及炎症细胞所占比例及绝对计数升高，且以分泌Th2型细胞因子如IL4为主；血清IgE、IgG1水平升高；肺组织病理切片观察到支气管、细支气管上皮下和小血管周围有明显的炎性细胞浸润，以嗜酸性粒细胞为主，气道上皮结构紊乱，有部分脱落，上皮下充血水肿明显，肺泡间质增厚，也可见到炎性细胞浸润。给予相应免疫治疗后，肺组织炎症反应明显减轻，表现为BALF中细胞总数减少，炎症细胞数减少，且其和SCCS中n1型细胞因子如IFN-γ占主导；血清IsE、IsG1水平降低，IgG2a水平升高；肺组织病理切片观察到细胞浸润程度明显减轻，气道结果基本恢复正常。结论：本实验研究成功地建立了小鼠哮喘模型。分别用屋尘螨粗浸液及rDerp2进行免疫治疗均显示良好疗效，但前者比后者疗效好。     

淋巴结注射免疫治疗对特应性皮炎患者血清屋尘螨sIgE、IL-4和INF-γ的影响

目的探讨淋巴结注射免疫治疗特应性皮炎的分子免疫学机制。方法 72例对屋尘螨过敏的特应性皮炎患者,随机分为治疗组和对照组,每组各36例,对照组给予0.1%糠酸莫米松乳膏、1.2%维生素B6软膏、氯雷他定片、富马酸酮替芬等基础药物治疗,治疗组在上述药物治疗的基础上,超声引导下分别于0周、4周、8周、12周、16周、20周行腹股沟淋巴结内注射屋尘螨过敏原制剂,除0周用药剂量为100 SQ-U外,其余5次剂量均为1 000 SQ-U。治疗前后采用荧光酶联免疫法检测特应性皮炎患者血清屋尘螨sIgE、采用酶联免疫吸附试验(ELISA)方法检测患者血清IL-4和INF-γ值。检测数据应用SPSS19.0统计学软件进行分析。结果 2组中所有患者均完成了20周的治疗。治疗后治疗组血清屋尘螨sIgE和IL-4值由治疗前的(5.06±2.30)KU/L和(16.41±0.91)ng/L分别降至(2.14±1.09)KU/L和(9.52±0.75)ng/L,且均明显低于治疗后对照组(4.63±1.13)KU/L和(16.40±0.92)ng/L,2组比较差异有显著统计学意义(P0.01);治疗组血清INF-γ值由治疗前的(11.34±0.71)ng/L增至(14.78±0.68)ng/L,且明显高于对照组的值(11.32±0.58)ng/L,2组比较有显著性统计学差异(P0.01)。结论屋尘螨过敏原淋巴结注射免疫治疗显著降低患者血清屋尘螨sIgE和IL-4值,同时使血清INF-γ值升高。降低血清sIgE、调节血清IL-4和INF-γ的平衡可能是淋巴结注射免疫治疗的分子免疫机制。     

BCG30主要分泌蛋白对尘螨变应性患者TH1/TH2平衡调节作用的观察

目的　研究结核杆菌相对分子质量 (Mr)为 30× 10 3的主要分泌蛋白 (BCG30 ,也称Ag85B)对尘螨变应原过敏所致的哮喘等变应性患者外周血单个核细胞 (PBMC)分泌TH1、TH2细胞因子的调控作用。方法　常规分离 2 7例尘螨过敏的变应性患者 (A) ,其中 18例哮喘患者 (A1)、9例变应性鼻炎或皮炎患者 (A2 )和 13例正常人 (B)的PBMC ,在离体与螨变应原、BCG30单独或复合共培养 ,ELISA法测定培养上清IL 5、IFN γ的水平。结果　A、A1、A2、B 4组无刺激状态下的IL 5、IFN γ水平无差异 (P >0 .0 5 )。尘螨变应原刺激可显著促进A、A1、A2 3组PBMC分泌IL 5 ,P均 <0 .0 5 ,同时 ,A组的IFN γ水平自身比较亦明显增高 (73.5 8pg ml± 30 .2 3pg mlvs 30 .71pg ml± 18.87pg ml,P <0 .0 5 )。将尘螨变应原与BCG30和PBMC进行复合培养 ,并与单独尘螨变应原刺激组比较 ,其IFN γ水平在A组 (92 .89pg ml± 2 9.0 7pg mlvs 73.5 8pg ml± 30 .2 3pg ml)和A1组 (87.6 0pg ml± 36 .4 5pg mlvs 5 8.75pg ml± 7.84pg ml)均较后者为高 (P均 <0 .0 5 ) ,且A组的IFN γ IL 5的比值较单独尘螨变应原刺激组显著增高 (5 .0 3± 1.36vs 4 .2 0± 1.6 4 ,P <0 .0 5 ) ,而A1组其比值亦有增高趋势 (P =0 .0 7)。正常人中各刺激组间所有指标均     

TLR4基因3’未翻译区11367位点多态性与儿童哮喘相的相关性

目的探讨TLR4基因3’未翻译区(3’UTR)11367位点的多态性在儿童哮喘人群中的分布及其与患儿特应质、肺炎支原体感染、过敏原和肺功能参数的关系。方法本研究纳入哮喘患儿222例,正常对照290例。采用单管双向等位基因特异性扩增技术(SB-ASA)检测TLR4基因3’UTR 11367位点的基因多态性。使用被动凝集法检测血清肺炎支原体抗体滴度。通过皮肤点刺试验(Skin prick test,SPT)检测常见过敏原。结果哮喘组中TLR4 G11367C位点基因型GG、GC/CC的频率分别是89.6%和10.4%,等位基因G、C的频率分别是93.8%和6.2%,与对照组相比差异无统计学意义(P>0.05);相较于GC型,GG型的哮喘患儿湿疹史更高(P=0.024,OR=2.957,95%CI为1.117～7.828),屋尘螨过敏程度也较GC型重(P=0.021);GG型和GC型患儿肺功能水平没有显著性差异。结论 TLR4基因3’UTR基因多态性与儿童哮喘易感性不相关,但与哮喘患儿有无湿疹史及屋尘螨的过敏程度相关。     

母亲过敏性哮喘病史对新生儿调节性T细胞的影响

目的:研究母亲过敏性哮喘病史对新生儿调节性T细胞的影响。方法:收集62例胎儿脐带血[40例健康母亲(对照组),22例母亲有过敏性哮喘病史(哮喘组)],分离单个核细胞进行体外培养,每例样品均分别给予以下4种刺激:类脂A(LpA)-Toll样受体4的配体,肽多糖(Ppg)-Toll样受体2的配体,植物血凝素(PHA),屋尘螨提取物。培养3天后,应用流式细胞技术检测CD4+CD25+Foxp3+调节性T细胞数量;Luminex流式荧光仪检测特异性细胞因子分泌浓度;体外分离CD4+CD25+调节性T细胞与CD4+CD25-效应T细胞共同培养,检测调节性T细胞对效应细胞的增殖和分泌细胞因子的抑制功能。结果:在Ppg诱导的免疫反应中,与对照组相比,过敏组脐带血中调节性T细胞数量(CD4+CD25+Foxp3+T细胞)减少;相关细胞因子IL-10分泌降低,差异具有统计学意义。在PHA诱导的免疫反应中,与对照组相比,调节性T细胞对效应细胞增值的抑制功能下降,差异具有统计学意义;对于效应细胞分泌IL-13的抑制功能也趋向于降低。结论:母亲有过敏性哮喘病史的新生儿脐带血中,调节性T细胞的数量和功能存在缺陷,可能与其易患过敏性疾病有关。     

SARS康复者特异性细胞免疫和免疫记忆T细胞功能的研究

目的　观察完全康复期严重急性呼吸综合征 (SARS)患者外周血针对SARS冠状病毒(SARS CoV)S抗原多肽的特异性细胞免疫反应。方法　分离外周血单个核细胞 (PBMC) ,经混合S抗原多肽刺激后 ,采用酶联免疫吸附试验 (ELISA)和酶联免疫斑点试验 (ELISPOT)检测 ,分析完全康复期SARS患者抗原特异性T淋巴细胞应答反应。结果　当SARS CoV的S抗原混合多肽刺激后 ,只有SARS康复期患者的PBMC分泌大量的IFN γ。同时 ,IFN γ产生细胞的阳性率也显著高于健康对照组 (P <0 .0 5)。此外 ,当用多克隆刺激剂 (PMA +ionomycin)刺激后 ,正常人和康复期SARS患者的PBMC产生等量的IFN γ及IFN γ产生细胞 ,两者经统计学处理 ,差异无统计学意义 (P >0 .0 5)。结论SRAS CoV不仅能诱导中和抗体的产生 ,而且还可诱导抗原特异性细胞免疫应答反应 ,并可在体内长期维持免疫记忆功能。     

Alutard-SQ与国内螨过敏原浸液的对照分析

目的　比较Alutard -SQ与中国现有过敏原浸液 ,了解国内过敏原浸液的状况 .方法　 91例受试者 ,其中支气管哮喘或合并过敏性鼻炎 81例 ,10例正常人作对照 .实验组及对照组均行Alutard 和国内过敏原浸液皮肤点刺试验 ,测量风团及伪足的直径 ,比较两种过敏原浸液两种尘螨 (粉尘螨D .f.、屋尘螨D .p .)的差异 .结果两种尘螨过敏原浸液风团及伪足的直径有显著性差异 (p<0 .0 5 ) ,Alutard -SQ皮肤试验结果与特异性IgE水平相关性好 ,国内过敏原浸液皮肤试验与特异性IgE水平相关性差 .结论　国内过敏原浸液的质量仍需改善     

Long-term effects of specific immunotherapy, administered during childhood, in asthmatic patients allergic to either house-dust mite or to both house-dust mite and grass pollen

In a retrospective study, asthmatic patients allergic to either house-dust mite (HDM) (Dermatophagoides pteronyssinus) (n = 34) or to both HDM and grass pollen (GP) (n = 14), and who were treated with specific immunotherapy (SIT) during childhood (mean duration of SIT: 61 +/- 9.70 months), were re-evaluated in early adulthood after mean cessation of SIT for 9.3 +/- 2.76 years. The results were compared to those of a control group of asthmatic patients (n = 42) with comparable asthma features, who were treated with appropriate antiasthmatic drugs during childhood, but who never received SIT. Re-evaluation was carried out with a standardized questionnaire, skin prick tests (SPT), and lung-function assessments. At the time of re-evaluation, the mean age in the SIT-treated group was 23.1 +/- 3.50 years; in the control group, it was 22.7 +/- 3.40 years. At re-evaluation, the risk of frequent asthmatic symptoms was three times higher in the control group than in the SIT-treated group (prevalence ratio: 3.43; P = 0.0006). The frequent use of antiasthmatic medication was also more pronounced in the control group, although the difference was not statistically significant (P=0.38). Lung-function parameters and results of SPT with HDM were comparable in both groups. It is concluded that SIT has long-term effects on asthmatic symptoms in young adults.     

Benefits of immunotherapy with a standardized Dermatophagoides pteronyssinus extract in asthmatic children: a three-year prospective study

BACKGROUND: Although widely practiced for over 80 years, the role of specific immunotherapy (SIT) in pediatric asthma treatment is still controversial. We assessed the effects of a 3-year period of subcutaneous administration of a standardized preparation of Dermatophagoides pteronyssinus (D pt) on the respiratory health in a group of asthmatic children monosensitized to house dust mite (HDM). METHODS: A randomized clinical trial was performed after 1-year run-in period. Fifteen children receiving SIT for HDM and 14 controls (four drop-outs), matched for age, allergen sensitization, asthma severity, lung function, and non-specific bronchial reactivity (BHR), were studied during the 3-year treatment period. During the whole trial, respiratory symptoms, pharmacological and respiratory function parameters were regularly evaluated. Skin prick tests and methacholine challenge were performed at the beginning and end of the study. RESULTS: In the SIT group significant improvement in asthmatic symptoms and marked reduction in drug intake was observed. The SIT group also showed a significant decrease in non-specific bronchial BHR. No new sensitivity occurred during the study period in the SIT group only. No major local or systemic side-effects were reported during the study. CONCLUSIONS: Our results confirm that SIT is effective in asthmatic children sensitive to mites. It is associated with a decrease in BHR and it may prevent the development of new sensitizations in monosensitized subjects.     

Effect of specific immunotherapy with house dust mite extract on the bronchial responsiveness of paediatric asthma patients

BACKGROUND AND OBJECTIVE: Allergic asthma is common in children, and house dust mite (HDM) is an important source of perennial allergens. Bronchial hyperresponsiveness is a functional hallmark of asthma. Specific immunotherapy (SIT) with HDM extracts were shown to decrease symptoms, but its effect on bronchial responsiveness, as measured by non-pharmacological challenges, has not been evaluated. METHODS: Twenty-six paediatric asthma patients allergic to HDM participated in this study. Fourteen patients received SIT with a HDM extract (Alavac, Bencard) for 2 years, and 12 served as controls. Bronchial responsiveness was assessed non-pharmacologically by cold dry air challenge (CACh) before and 3, 6, 12 and 24 months after SIT, and 12 months after termination of SIT. RESULTS: After 24 months, the SIT group showed a statistically significant reduction of the mean CACh-induced changes of both forced expiratory volume in one second (-21.8+/-2.7% vs. -13.7+/-2.4%; P = 0.03) and maximal expiratory flow at 25% remaining vital capacity (-48.9+/-4.9% vs. -27.9+/-6.2%; P = 0.01). In contrast, no significant changes of bronchial responsiveness were observed in the control group. In the SIT group more patients lost their bronchial hyperresponsiveness than in the control group (6/14 vs. 1/12; P<0.05). One year after terminating SIT, the treatment group showed a tendency towards returning bronchial hyperresponsiveness. CONCLUSION: These results demonstrate that during 2 years of SIT there was a reduction of bronchial hyperresponsiveness in HDM-allergic paediatric asthma patients.     

Development of new sensitizations in asthmatic children monosensitized to house dust mite by specific immunotherapy

It has been hypothesized that specific immunotherapy (SIT) significantly decreases the development of new allergen sensitizations in mono-sensitized patients. In this study, we evaluated the effect of SIT on the development of new allergen sensitizations in 129 asthmatic children mono-sensitized to house dust mite. SIT was accepted by only 70 of them (SIT group). The remaining 59 children were treated only with medication (control group). At the end of the study we found that 33% of all patients developed new sensitizations. Surprisingly, the prevalence of new sensitizations was significantly higher in the SIT group (45.5%) than in the control group (18.1 %). Ash tree (Fraxinus excelsior), Olive and Meadow fescue (Festuca elatior) were the most common allergens responsible for the new sensitizations. We conclude that SIT did not prevent the onset of new sensitizations in asthmatic children mono-sensitized to house dust mite.     

Steroid-sparing effect of subcutaneous SQ-standardised specific immunotherapy in moderate and severe house dust mite allergic asthmatics

BACKGROUND: The present study evaluated the steroid-sparing effect of subcutaneous SQ-standardized specific immunotherapy (SIT) in moderate and severe house dust mite (HDM) allergic asthmatics. METHODS: Fifty-four adult asthmatics allergic to HDM requiring at least inhaled corticosteroids (ICS) doses equivalent to 500 microg fluticasone propionate daily were randomized to subcutaneous SIT or placebo injections for a period of 3 years. The minimum required ICS dose, 4 week diary of asthma symptom score, use of rescue medication, peak expiratory flow (PEF) measurements and visual analog scale for asthma symptoms were assessed before start of treatment and after 1, 2 and 3 years of treatment. RESULTS: In patients with moderate and severe asthma, the reduction in ICS was statistical significant after 2 years of treatment (P = 0.03) but not after 3 years. The median reductions were 82% and 42% after the third year for active and placebo respectively. In patients with moderate persistent asthma the reduction was statistical significant larger for those treated with SIT compared with placebo after year 2 and year 3. The median reductions after 3 years were 90% for SIT and 42% for placebo (P = 0.04). Despite significant steroid reduction, there was no difference in asthma assessments between the two groups. No serious reactions related to SIT injections were seen. CONCLUSION: This study shows that SIT with a SQ-standardized HDM extract is safe. An ICS sparing effect was evident in patients with moderate persistent asthma.     

Prevention of new sensitizations in asthmatic children monosensitized to house dust mite by specific immunotherapy. A six-year follow-up study.

BACKGROUND: Specific immunotherapy (SIT) is a recognized way of treating IgE-mediated respiratory diseases. The clinical outcome is usually better in allergic children than in adults. OBJECTIVE: To increase our knowledge of the ability of SIT to prevent the onset of new sensitizations in monosensitized subjects, so far poorly documented. METHODS: 134 children (age range 5-8 years), who had intermittent asthma with or without rhinitis, with single sensitization to mite allergen (skin prick test and serum-specific IgE), were enrolled. SIT was proposed to all the children's parents, but was accepted by only 75 of them (SIT Group). The remaining 63 children were treated with medication only, and were considered the Control Group. Injective SIT with mite mix was administered to the SIT Group during the first three years and all patients were followed for a total of 6 years. All patients were checked for allergic sensitization(s) by skin prick test and serum-specific IgE every year until the end of the follow-up period. RESULTS: Both groups were comparable in terms of age, sex and disease characteristics. 123 children completed the follow-up study. At the end of the study, 52 out of 69 children (75.4%) in the SIT Group showed no new sensitization, compared to 18 out of 54 children (33.3%) in the Control Group (P < 0.0002). Parietaria, Gramineae and Olea were the most common allergens responsible for the new sensitization(s). CONCLUSIONS: According to our data, SIT may prevent the onset of new sensitizations in children with respiratory symptoms monosensitized to house dust mite (HDM).     

Allergen specific immunotherapy attenuates early and late phase reactions in lower airways of birch pollen asthmatic patients: a double blind placebo-controlled study

BACKGROUND: Few placebo-controlled studies have examined the effect of allergen specific immunotherapy (SIT) on early and late phase asthmatic reactions. In this placebo-controlled study we have investigated the effect of 1 year of SIT with standardized birch pollen extract on early and late phase asthmatic reactions in adult asthmatic patients. METHODS: Nineteen patients with a history of birch-pollen-induced seasonal symptoms from upper and lower airways, positive skin prick test and in vitro specific immunoglobulin E to birch pollen extract were included. Allergen and methacholine bronchial challenges were performed and blood samples obtained for analyses of total eosinophil count and eosinophil cationic protein (ECP) in serum, before and after 1 year of immunotherapy treatment. RESULTS: All patients developed early and 16 of 19 both early and late phase asthmatic reactions. A significant increase in allergen dose was required to evoke early asthmatic reaction in the immunotherapy group (P < 0.01) after 1 year of treatment. The difference between the groups was significant (P < 0.01). Also the size of late asthmatic reaction was significantly reduced in the SIT group compared with placebo treated patients (P < 0.01). Twenty-four hours after allergen challenge methacholine sensitivity, number of total eosinophils and ECP increased significantly in the placebo (P < 0.02, P < 0.05 and P < 0.05 respectively), but not in the SIT group. CONCLUSION: Allergen SIT with standardized birch pollen extract decreased early and late asthmatic responses following bronchial challenge in pollen allergic patients, thus confirming anti-inflammatory effect of the treatment.     

Bronchial inflammation in mite-sensitive asthmatic subjects after 5 years of specific immunotherapy.

We examined the pattern and degree of the inflammatory process in bronchial biopsy specimens taken by fiberoptic bronchoscopy in eight asthmatic subjects (two women aged 19-38 years) after 5 years of specific immunotherapy (SIT) to mite extracts (SIT group). At the time of study, they received a maintenance dose of mite-extracts (last subcutaneous administration 3 weeks before bronchoscopy). Results were compared with those found in eight matched mite-sensitive subjects with stable asthma (two women aged 19-36 years; non-SIT group) and in eight healthy individuals (four women aged 22-29 years; control group). Bronchial biopsy specimens were fixed in periodate-lysine-paraformaldehyde, embedded in glycol methacrylate, and stained with hematoxylin-eosin and 2% toluidine blue. Number of eosinophils, mast cells, and total nucleated cells were counted separately in the epithelium and lamina propria by light microscopy and expressed as cells/high power field. Within the epithelium, eosinophil and mast cell counts in SIT and non-SIT groups were significantly higher compared to controls, whereas total cell counts were not statistically different. Within the lamina propria, total cell count in SIT and non-SIT groups was significantly higher compared with the control group, whereas mast cells were similar. The number of eosinophils in both SIT and non-SIT groups was higher compared with controls; however this reached statistical significance only in SIT-groups. Comparison between the two groups of asthmatics did not show any significant difference for any cell counts.(ABSTRACT TRUNCATED AT 250 WORDS)     

Usefulness of specific immunotherapy in patients with severe perennial allergic rhinitis induced by house dust mite: a double-blind, randomized, placebo-controlled trial

OBJECTIVES: To evaluate the effectiveness of specific immunotherapy (SIT) in patients with severe house dust mite (HDM)-induced perennial allergic rhinitis using diary cards and objective endpoints. PATIENTS AND METHODS: Thirty-six adult patients were selected with moderate to severe allergic rhinitis due to HDM allergy uncontrolled by regular anti-allergic drugs. Twenty-eight patients completed the study, 22 of these patients also had mild asthma. Subjects were stratified for HDM sensitivity on the basis of their 4-week diary card score and the size of their immediate and late-phase skin reaction to HDM. The groups were well matched for all relevant parameters. Patients were randomized to receive active preparation (Alutard(R)-SQ, ALK, Dermatophagoides pteronyssinus extract) or an identical placebo preparation. Increasing doses were administered until the maintenance dose was reached. This dose was then given once a month for 12 months. RESULTS: Clinical efficacy was evaluated by symptom medication diary cards recorded for 4 weeks after 12 months of continuous treatment and compared with pre-treatment scores. Skin test reactivity was re-measured after 12 months of treatment to HDM, cat dander and codeine phosphate. After 1 year of treatment, the actively treated group showed a 58% reduction in diary card symptom scores (P<0.002) and a 20% reduction in the use of rescue medication. The placebo group had a 32% reduction in symptom scores (P=NS), but no reduction in rescue medication requirements. The active group showed 36% reduction in skin prick test sensitivity to D. pteronyssinus (P=0.006), while the placebo group values were unchanged. Skin reactivity to codeine was unchanged in both groups. No significant adverse reactions to SIT were encountered. CONCLUSIONS: One year of SIT for D. pteronyssinus in patients with poorly controlled rhinitis (+/-mild asthma) produced clinically useful improvement as shown by symptom-medication diary cards and reductions in immediate skin reactions compared with placebo treatment.     

Effect of specific immunotherapy added to pharmacologic treatment and allergen avoidance in asthmatic patients allergic to house dust mite

BACKGROUND: Although several studies support the efficacy of specific immunotherapy in allergic asthma, its benefit compared with that of standardized pharmacologic intervention remains unknown. OBJECTIVE: A double-blind, placebo-controlled trial in 72 patients with mild-to-moderate asthma and allergy to house dust mite (HDM; Dermatophagoides species) was conducted to assess the effects of specific immunotherapy added to guideline-adjusted pharmacologic treatment and allergen avoidance. METHODS: After 1 observational year of pharmacologic treatment and standard measures of HDM avoidance, 2 groups of asthmatic subjects were randomly assigned to receive specific immunotherapy consisting of subcutaneous injections of either a mixture of Dermatophagoides pteronyssinus and Dermatophagoides farinae vaccine (n=41) or placebo (n=31) for 3 years. Medications were adjusted every 3 months according to the Global Initiative for Asthma guidelines. RESULTS: The adjustment of treatment was associated with a reduction in asthma symptom scores in all subjects. The addition of specific immunotherapy was associated with a decrease in the number of subjects requiring rescue bronchodilators, an increase in morning and evening peak expiratory flow, and a reduced skin sensitivity to HDM extracts. The addition of specific immunotherapy had no significant effects on the cumulative dose of inhaled corticosteroids, asthma symptoms, lung volumes, or bronchial responsiveness to methacholine. CONCLUSION: These results suggest that specific immunotherapy added to pharmacologic treatment and HDM avoidance provides marginal but statistically significant clinical benefits, possibly by reducing the allergic response of asthmatic patients sensitized to HDM.