Merget R, Heger M, Globisch A, Rasche K, Gillissen A, Gebler A, Schultze-Werninghaus G, Krieg M
Department of Internal Medicine, University Hospital Bergmann-sheil, Germany.
J Allergy Clin Immunol. 1997 Aug;100(2):199-207. doi: 10.1016/s0091-6749(97)70225-2.
Quantitative bronchial challenge tests with flour dust for the diagnosis of bakers' asthma may be performed by inhalation of flour delivered to the patient's respiratory tract by sophisticated equipment.
This study was carried out to assess the diagnostic value of bronchial challenge tests with flour dust inhalation from capsules administered by a Spinhaler (Fisons Inc., Loughborough, U.K.) and to compare this method quantitatively with bronchial challenge tests with a commercially available wheat flour extract.
A highly selected group of 36 bakers with work-related symptoms of rhinitis or asthma were referred to our department, a tertiary referral center, from 1992 to 1995. Thirty-four of the subjects and 10 atopic control subjects were included in this study. After the assessment of bronchial hyperresponsiveness on day 1, subjects were randomized to inhale an aqueous wheat flour extract at concentrations of 0.01, 0.1, 1, 10, and 100 mg/ml by tidal volume breathing for 10 minutes or to inhale wheat flour dust filled in capsules on days 2 and 3. One, two, and four capsules (maximum of 7 cumulative capsules) of flour dust were administered by a Spinhaler. In addition, skin prick tests were performed with a battery of environmental and occupational allergens. Total serum IgE and specific IgE to wheat flour were measured by standard procedures.
Seventeen bakers and two control subjects demonstrated a positive skin test response to wheat flour (wheal > or = 3 mm). Fifteen bakers demonstrated a fall of 50% or more in specific airway conductance after inhalation of the commercial wheat flour extract, and 11 demonstrated such a fall in specific airway conductance after inhalation of wheat dust. Three control subjects had a positive bronchial challenge response to the extract, but dust inhalation from the capsule did not cause positive bronchial reactions in control subjects. When a 50% fall of specific airway conductance was used as criterion for a positive bronchial provocation test result, sensitivity for the extract or dust inhalation was 0.44 and 0.32, respectively, and specificity was 0.7 and 1.0, respectively. If only subjects with a positive skin test response to wheat flour were considered, sensitivity of both tests was 0.65. With more stringent criteria for the gold standard, there was a trend for a higher sensitivity but a lower specificity of the extract inhalation. Both methods were safe.
The validity of bronchial challenge tests with wheat flour dust inhaled from Spinhaler capsules was superior to that of tests done with a commercially available aqueous wheat flour extract. The higher specificity of the Spinhaler method might be an advantage if bronchial challenge tests are used as confirmation tests.
可通过精密设备将面粉输送至患者呼吸道，进行面粉定量支气管激发试验以诊断面包师哮喘。
本研究旨在评估使用Spinhaler（英国拉夫堡Fisons公司）吸入胶囊中的面粉进行支气管激发试验的诊断价值，并将该方法与使用市售小麦粉提取物进行的支气管激发试验进行定量比较。
1992年至1995年，一组经过严格挑选的36名有与工作相关的鼻炎或哮喘症状的面包师被转诊至我们的三级转诊中心。本研究纳入了34名受试者和10名特应性对照受试者。在第1天评估支气管高反应性后，受试者被随机分组，通过潮气量呼吸10分钟，吸入浓度为0.01、0.1、1、10和100mg/ml的小麦粉水提取物，或在第2天和第3天吸入填充在胶囊中的小麦粉粉尘。通过Spinhaler给予1、2和4粒面粉粉尘胶囊（最多7粒累积胶囊）。此外，还对一系列环境和职业过敏原进行了皮肤点刺试验。通过标准程序测量血清总IgE和小麦粉特异性IgE。
17名面包师和2名对照受试者对小麦粉皮肤试验呈阳性反应（风团≥3mm）。15名面包师吸入市售小麦粉提取物后，特异性气道传导率下降50%或更多，11名面包师吸入小麦粉粉尘后出现特异性气道传导率下降。3名对照受试者对提取物支气管激发试验呈阳性反应，但吸入胶囊中的粉尘未在对照受试者中引起阳性支气管反应。当以特异性气道传导率下降50%作为支气管激发试验阳性结果的标准时，提取物或粉尘吸入的敏感性分别为0.44和0.32，特异性分别为0.7和1.0。如果仅考虑对小麦粉皮肤试验呈阳性反应的受试者，两种试验的敏感性均为0.65。对于金标准采用更严格的标准时，提取物吸入的敏感性有升高趋势，但特异性降低。两种方法均安全。
使用Spinhaler胶囊吸入小麦粉粉尘进行支气管激发试验的有效性优于使用市售小麦粉水提取物进行的试验。如果将支气管激发试验用作确诊试验，Spinhaler方法较高的特异性可能是一个优势。
