Table 3.
Characteristics of hairdressers with a negative specific inhalation challenge
| ID | Age (y) | WRAS | WRRS | Stop/resume test | Duration of exposure before symptoms (y) | Time from exposure to symptoms | Time since last exposure to persulphates (y) | Baseline FEV1/FVC (% of pred.) |
|---|---|---|---|---|---|---|---|---|
| 1 | 52 | + | + | N | 3 | Within hours | 5 | 86 (109 %) |
| 3 | 45 | + | + | P | 20 | Within hours | CE | 83 (104 %) |
| 4 | 49 | + | + | P | 28 | Within minutes | CE | 65 (81 %) Rever: 2.9 % |
| 6 | 30 | – | + | P | 10 | Within minutes | 3 | 81 (97 %) |
| 7 | 27 | + | + | P | 1 | Not definable | 1 | 84.9 (103.3 %) |
| 9 | 20 | + | + | P | 1 | Within minutes | CE | 98 (116 %) |
| 11 | 43 | + | + | P | 20 | Within hours | CE | 83 (103 %) |
| 12 | 23 | + | + | N | 3 | Within hours | CE | 74 (88 %) Rever: 12 % |
| 13 | 46 | + | – | N | 2 | Not definable | 3 | 83 (103 %) |
| 14 | 27 | + | + | P | 7 | Within minutes | CE | 83 (99 %) |
| 15 | 31 | + | + | P | 4 | Within minutes | 1/2 | 75 (90 %) Rever: 7.8 % |
| 17 | 20 | + | + | P | 4 | Not definable | 1/6 | 91 (108 %) |
| 18 | 29 | + | + | P | 8 | Within hours | CE | 91 (109 %) |
| ID | Age (y) | MCh PD20 (µg) | FeNO (ppb) | T-IgE (kU/L) | Atopya | HRT PP (mg/mL) | HRT SP (mg/mL) | HRT AP (mg/mL) |
|---|---|---|---|---|---|---|---|---|
| 1 | 52 | N | 25 | 3.6 | No | 1.25 | 0.63 | 1.25 |
| 3 | 45 | N | 9.9 | 6.7 | No | N | 5.0 | 2.5 |
| 4 | 49 | N | 16.0 | 2.2 | No | 10.0 | 10.0 | 5.0 |
| 6 | 30 | 400 | 64.1 | 155 | No | N | 10.0 | 5.0 |
| 7 | 27 | N | 19.3 | 127 | D | N | 5.0 | 2.5 |
| 9 | 20 | N | 6.6 | <2 | No | N | 10.0 | 5.0 |
| 11 | 43 | N | 7.1 | 22.5 | No | N | 10.0 | 5.0 |
| 12 | 23 | N | 21.8 | 122 | No | 10.0 | 5.0 | 2.5 |
| 13 | 46 | 626 | 12.1 | 35.4 | No | N | 5.0 | 1.25 |
| 14 | 27 | N | 11.8 | 3.7 | No | N | 10.0 | 5.0 |
| 15 | 31 | 720 | 9.0 | 308 | D | 5.0 | 2.5 | 1.25 |
| 17 | 20 | N | 9.0 | 4.3 | No | 10.0 | 2.5 | 2.5 |
| 18 | 29 | N | 19.7 | 58.3 | No | N | N | N |
y years, WRAS work-related asthma symptoms, WRRS work-related rhinitis symptoms, MCh methacholine challenge, FeNO fractional exhaled nitrogen oxide (increased values in italics), T-IgE total immunoglobulin E, HRT histamine release test, PP potassium persulphate, AP ammonium persulphate, SP sodium persulphate, SIC specific inhalation challenge, N negative, P positive, CE currently exposed, D dermographism, R rhinitis, A asthma
aDefined as ≥1 positive SPT to common inhalant allergens