Characteristics and clinical findings of BCMBA-sensitised workers examined at the Finnish Institute of Occupational Health
| Case number | 1* | 2* | 3 | 4 | 5 | 6 |
| Age | 31 | 29 | 23 | 26 | 33 | 34 |
| Current or ex-smoker | – | – | + | + | + | – |
| Duration of exposure, years | 2.5 | 2.0 | 1.5 | 1.0 | 4.0 | 1.5 |
| Duration of symptoms, years | 0.5 | 1 | 0.5 | 0.5 | 3 | 1 |
| BCMBA-related symptoms | ||||||
| Rhinitis | + | + | + | + | + | + |
| Asthma | – | + | + | – | – | – |
| Urticaria | + | + | + | – | – | + |
| Total IgE, kU/L | 120 | 46 | 1240 | 100 | 65 | 45 |
| Blood eosinophils cell/µg | 310 | 220 | 100 | 500 | 260 | 90 |
| Skin prick tests | ||||||
| Histamine weal size, mm | 5 | 5 | 6 | 7 | 7 | 8 |
| Negative control weal size, mm | 0 | 0 | 0 | 0 | 0 | 2† |
| BCMBA weal size, mm | 10 | 6‡ | 8 | 4 | 6 | 5 |
| Positive to common aeroallergen | + | + | + | + | + | – |
| Open skin application test to BCMBA | + | + | + | NT | NT | – |
| FEV1% of predicted | 101 | 109 | 88 | 84 | 89 | 102 |
| FVC% of predicted | 102 | 112 | 96 | 103 | 98 | 98 |
| Hyperresponsiveness | – | + | - | - | - | NT |
| FeNO, ppb | 38.2 | 48.8 | 32.5 | 6.0 | 21.1 | 30.5 |
| Specific inhalation challenge reaction | ||||||
| Type of FEV1 reaction, maximum FEV1 decrease | NT | +Early, 17% | +Early, 48% | – | – | NT |
| FeNO increase | NT | + 22 ppb | + 22 ppb | – | – | NT |
| Hyperresponsiveness increase | NT | – | + 3-fold | – | + 2-fold | NT |
| Nasal reaction, secretion weight | NT | + 4660 mg | – § | + 220 mg | + 1550 mg | +¶ 4000 mg |
*Index cases examined before surveillance.
†Considered as true positive SPT to BCMBA although 2 mm weal to negative control was detected.
‡Pseudopod reaction.
§Exposure time was short (15 min) due to asthma reaction.
¶Nasal provocation test.
BCMBA, 3-(Bromomethyl)−2-chloro-4-(methylsulfonyl)- benzoic acid; FeNO, fractional exhaled nitric oxide; FEV1, forced expiratory volume in one second; FVC, forced vital capacity; SPT, skin prick test.