De Zotti R, Bovenzi M, Negro C, Cirla A, Innocenti A, Lorusso A, Mariano A, Paggiaro P L, Talini D, Pisati G, Romano C, Sulotto F
Institute of Occupational Medicine, University of Trieste, Via della Pietà 19, I-34129 Trieste, Italy.
Int Arch Occup Environ Health. 1999 Aug;72(5):335-7. doi: 10.1007/s004200050384.
The aim of this study was to evaluate the outcome of the specific inhalation challenge test (SIC) in 160 subjects with suspected baker's asthma and to assess its relation to total flour dust levels and to personal characteristics such as specific skin sensitisation, non-specific bronchial hyper-responsiveness (NSBH) and atopy.
We investigated the outcome of SIC tests performed with wheat flour in six Italian laboratories. For each subject, data was available regarding skin sensitisation to wheat flour, NSBH, atopy, forced expiratory volume at 1 s (FEV1) monitoring and airborne flour dust in the challenge chamber measured by the gravimetric method (total dust in mg/m(3)).
The SIC test was positive for early asthma in 42 subjects (26%) and for late/dual asthma in 18 (11%). Positive outcome to SIC was significantly associated with NBSH (odds ratio, OR: 3.5, 95% CI: 1. 6-7.7) and skin sensitisation to wheat flour (OR: 3.1, 95% CI: 1.3-7. 0). Exposure level to wheat flour was less than or equal to 10 mg/m(3 )in 12% of individuals, ranged between 11 and 30 mg/m(3) in 43% and exceeded 30 mg/m(3) in 45%. The outcome of SIC was always negative among workers not skin sensitised to wheat flour and without NSBH and atopy. An increasing prevalence of positive SIC was observed among workers with one or more of the above-mentioned personal characteristics whose challenge exposure was greater than 10 mg/m(3) (P < 0.001).
Procedures currently adopted for wheat flour dust exposure during SIC need to be better standardised in order to avoid excessive airborne dust exposure. Over-exposure seems to be of no use for the diagnosis and risks making the asthmatic reaction worse, particularly in patients who are both sensitised to wheat allergens and have NSBH and/or atopy.
本研究旨在评估160名疑似面包师哮喘患者的特异性吸入激发试验（SIC）结果，并评估其与面粉总粉尘水平以及特异性皮肤致敏、非特异性支气管高反应性（NSBH）和特应性等个人特征之间的关系。
我们在六个意大利实验室调查了用小麦粉进行的SIC试验结果。对于每个受试者，可获得有关对小麦粉的皮肤致敏、NSBH、特应性、第1秒用力呼气量（FEV1）监测以及用重量法测量的激发试验室内空气中面粉粉尘（总粉尘，mg/m³）的数据。
SIC试验对42名受试者（26%）的早期哮喘呈阳性，对18名受试者（11%）的晚期/双重哮喘呈阳性。SIC阳性结果与NSBH（优势比，OR：3.5，95%置信区间：1.6 - 7.7）和对小麦粉的皮肤致敏（OR：3.1，95%置信区间：1.3 - 7.0）显著相关。12%的个体小麦粉暴露水平小于或等于10 mg/m³，43%的个体暴露水平在11至30 mg/m³之间，45%的个体暴露水平超过30 mg/m³。对小麦粉无皮肤致敏且无NSBH和特应性的工人中，SIC结果始终为阴性。在具有上述一种或多种个人特征且激发试验暴露大于10 mg/m³的工人中，观察到SIC阳性患病率增加（P < 0.001）。
为避免空气中粉尘过度暴露，目前SIC期间小麦粉粉尘暴露所采用的程序需要更好地标准化。过度暴露似乎对诊断无用，且有使哮喘反应恶化的风险，特别是对于对小麦过敏原致敏且有NSBH和/或特应性的患者。
