哮喘患儿皮肤点刺试验反应强度与呼气一氧化氮和肺功能的关系

目的 将不同阳性级别过敏原皮肤点刺试验（Skin prick test,SPT）哮喘儿童的呼气一氧化氮（FeNO）和肺功能进行比较,探讨皮肤点刺试验反应强度与呼气一氧化氮和肺功能的关系.方法 回顾分析进行了过敏原SPT的哮喘患儿94例,根据屋尘螨和粉尘螨反应强度分为3组：SPT结果为（＋＋＋）～（＋＋＋＋）患儿33例为A组,SPT结果为（＋）～（＋＋）患儿31例为B组,SPT结果为（-）患儿30例为C组,评价患儿FeNO和FEV1/FVC百分比.结果 3组患儿FEV1/FVC百分比分别为A组（94.00±6.46）、B组（96.46±5.12）和C组（95.76±6.19）,差异无统计学意义（P＞0.05）.3组FeNO值分别为A组（57.96±20.06） ppb、B组（42.72±14.07）ppb和C组（30.54±14.63）ppb,差异有统计学意义（P＜0.05）,且随着SPT中变应原反应强度增加而增加.结论 呼气一氧化氮能较好地反映过敏性哮喘患儿的气道炎症,明显优于肺功能检查,可用于过敏性哮喘的诊断和气道炎症的评估.     

ABC-ELISA检测血清粉尘螨特异性IgE

目的　应用ABC -ELISA法检测粉尘螨特异性IgE。 方法　按常规ABC -ELISA法操作 ,以阳性血清光密度值1 0时所需要的条件为最适条件 ,经预实验选择最适抗原包被浓度、血清稀释度和酶结合物浓度 ,并经特异性抑制试验验证。用ABC -ELISA法对 76例哮喘患者和 30例正常人进行粉尘螨特异性IgE检测 ,并与皮肤挑刺试验结果比较。 结果　ABC -ELISA法检测粉尘螨特异性IgE最适抗原包被浓度为 10 μg/ml,血清稀释倍数为 1∶4 0 ,Avidin -HRP为 1∶6 0 0 ,粉尘螨浸液和鼠抗人IgE均能抑制阳性反应。支气管哮喘患者和正常人粉尘螨特异性IgE校正OD值分别为 2 4 1± 1 13和 1 2 5± 0 5 6 ,差异具显著性 (χ2 =5 36 ,P <0 0 1)。粉尘螨浸液皮试与螨特异性IgE测定的符合率为 93 4 0 % (99/10 6 )。 结论　ABC -ELISA法检测粉尘螨特异性IgE耗时短 ,且具有较好的抗原特异性 ,建议临床推广应用。     

Comparative effectiveness of allergy testing method in driving immunotherapy outcomes

Background

Skin‐prick testing (SPT), in vitro testing (IVT), and intradermal‐dilutional testing (IDT) are methods to detect patient sensitivities to specific allergens and direct immunotherapy dosing. We used objective and subjective measures of improvement to compare outcomes based on test method.

Methods

Patients underwent 1 of 3 protocols: SPT, screening SPT followed by IDT, or IVT. We used institution billing data to do a cost analysis of these tests. The time to maintenance (TTM) therapy was analyzed and patients were stratified into high and low reactors. The Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) was used to quantify symptoms pre‐maintenance and post‐maintenance.

Results

Of 177 patients (SPT, n = 40; IVT, n = 91; IDT, n = 46), 115 (SPT, n = 35; IVT, n = 39; IDT, n = 41) were high reactors. Out of 90 patients (SPT, n = 17; IVT, n = 37; IDT, n = 36) reaching maintenance, 58 were high reactors (SPT, n = 15; IVT, n = 12; IDT, n = 31). Overall, SPT, IVT, and IDT median TTM were 542, 329, and 578.5 days, respectively. IDT TTM was shorter compared to IVT overall and in high reactors (hazard ratio [HR] = 1.91, p = 0.02; HR = 2.12, p = 0.03), but was not significant compared to SPT high reactors (p = 0.33). The IDT cost was $62.66, translating to an incremental cost‐effectiveness ratio of $0.23 per day of shortened TTM. Median RQLQ change for the SPT, IVT, and IDT groups was 6.5, 1, and 1.5, respectively, but was not significant (p = 0.60).

Conclusion

IDT reached maintenance immunotherapy quicker than IVT but there was no difference compared to SPT. TTM did not correlate with improvements in patient symptoms between testing methods. This study represents a novel comparison of outcomes based on initial allergy testing method.

     

Atopy patch test reactions to Malassezia allergens differentiate subgroups of atopic dermatitis patients

BACKGROUND: The yeast Malassezia is considered to be one of the factors that can contribute to atopic dermatitis (AD). OBJECTIVES: To investigate the reactivity to Malassezia allergens, measured as specific serum IgE, positive skin prick test and positive atopy patch test (APT), in adult patients with AD. METHODS: In total, 132 adult patients with AD, 14 with seborrhoeic dermatitis (SD) and 33 healthy controls were investigated for their reactions to M. sympodialis extract and three recombinant Malassezia allergens (rMal s 1, rMal s 5 and rMal s 6). RESULTS: Sixty-seven per cent of the AD patients, but only one of the SD patients and none of the healthy controls, showed a positive reaction to at least one of the Malassezia allergens (extract and/or recombinant allergens) in at least one of the tests. The levels of M. sympodialis-specific IgE in serum correlated with the total serum IgE levels. Elevated serum levels of M. sympodialis-specific IgE were found in 55% and positive APT reactions in 41% of the AD patients with head and neck dermatitis. A relatively high proportion of patients without head and neck dermatitis and patients with low total serum IgE levels had a positive APT for M. sympodialis, despite lower proportions of individuals with M. sympodialis-specific IgE among these groups of patients. CONCLUSIONS: These results support that Malassezia can play a role in eliciting and maintaining eczema in patients with AD. The addition of an APT to the test battery used in this study reveals a previously overlooked impact of Malassezia hypersensitivity in certain subgroups of AD patients.     

A multicentre study assessing the prevalence of sensitizations in patients with asthma and/or rhinitis in China

Background: The prevalence of sensitization in patients with asthma and rhinitis in mainland China remains unclear. Objective: Our aim was to estimate the prevalence of allergy in patients with respiratory allergic diseases such as asthma and/or rhinitis attending respiratory clinics within mainland China. The study also investigated regional and annual differences in the prevalence and pattern of sensitization among the patients in China. Method: A cross‐sectional survey was performed in 6304 patients suffering from asthma and/or rhinitis in 17 cities from 4 regions of China. Patients completed a standardized questionnaire asking for the presence of respiratory and allergic symptoms. They also underwent skin prick tests with 13 common aeroallergens. Results: Among the 6304 patients, 4545 (72.1%) had at least one positive skin prick reaction. The overall prevalence of positive skin prick responses was 59.0% for Dermatophagoides farinae, 57.6% for Dermatophagoides pteronyssinus, 40.7% for Blomia tropicalis, 16.1% for American cockroach, 14.0% for dog, 11.5% for Blatella germanica, 11.3% for Artemisia vulgaris, 10.3% for cat, 6.5% for Ambrosia artemisifolia, 6.3% for mixed mould I, 4.4% for mixed mould IV, 3.5% for mixed grass pollen and 2.2% for mixed tree pollen. Sensitizations to common allergens varied widely between geographical areas and demonstrated unique pattern in patients by stratification with age groups, with asthma and/or rhinitis. Severity of rhinitis and asthma was significantly correlated with skin index of reactivity to Artemisia vulgaris, Ambrosia artemisifolia and to D. pteronyssinus, D. farinae and Blomia tropicalis respectively (P < 0.001). Positive reactivity to the tested allergens and concomitant reactivity to multiple allergens including to house dust mites and Blomia tropicalis was markedly increased in patients with both asthma and rhinitis. Conclusion: House dust mites were the most prevalent allergens in patients with asthma and/or rhinitis in China. There were significant differences in patterns of sensitizations in patients from different geographical areas, age groups as well as asthma and/or rhinitis.