Table 2 Skin and blood tests for allergy, lung function and induced sputum of case 2.
| Skin prick test | ||||
| Common aeroallergens (Alk)* | Negative | |||
| Baking allergens (Alk) | ||||
| Wheat flour | Positive† | |||
| Rye flour | Negative | |||
| Oat flour | Negative | |||
| Corn flour | Negative | |||
| Soy flour | Negative | |||
| Total IgE | Increased (190 kU/l) | |||
| Specific serum IgE (ImmunoCAP Pharmacia) | Wheat | Positive (16 kUA/l) | ||
| α‐Amylase | Negative (<0.35 kUA/l) | |||
| FEV1 | 3.49 litres (106% predicted value) | |||
| FVC | 4.62 litres (110% predicted value) | |||
| FEV1/FVC | 78% | |||
| Peak expiratory flow rate‡ | Daily variability <20% | |||
| PD20§ | >3200 μg | |||
| Induced sputum | After the work shift | While asymptomatic (still exposed at work but taking inhaled steroids) | While asymptomatic (not exposed at work) | After flour bronchial challenge |
| Total cell count (×106/ml) | 1.0 | 0.4 | 0.6 | 2.3 |
| Non‐squamous epithelial cells (%) | ||||
| Neutrophils | 8 | 6 | 5 | 4 |
| Eosinophils | 40 | 2 | 0 | 54 |
| Macrophages | 52 | 92 | 95 | 42 |
FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; PD20, provocative dose inducing a 20% fall in FEV1.
*House dust mites, pollens, cat and dog dander, moulds such as Alternaria alternata, Aspergillus fumigatus and Cladosporium herbarum.
†Skin prick test positivity: a weal diameter of 5 mm, more than one half of that of the histamine control.
‡Peak expiratory flows measured six times daily for 4 weeks without significant changes at work or away from work.
§Methacholine challenge performed soon after the work shift (in the morning after the night shift) at a maximal dose–response curve.