Exhaled air nitric oxide and laboratory animal allergy

Allergens from rats, mice, guinea pigs or rabbits cause up to 30% of exposed persons to develop specific Immunoglobulin E (IgE) responses. Laboratory animal allergy (LAA) is among the highest occupational risks for asthma in the UK. . In LAA often symptoms progress from conjunctivitis, rhinitis to asthma. Health surveillance of workers is performed with the aim of detecting early sensitisation. Currently this involves questionnaires and simple lung function tests supplemented by skinprick tests with or without specific Ig E measurements in serum samples.It is now known that elevated levels of nitric oxide (NO) in exhaled breath are associated with constitutional asthma. A cross-sectional study was performed in 39 workers undergoing LAA health surveillance to assess whether an association exists between LAA and NO. Volunteers completed two health questionnaires, had skinprick tests, spirometry, total IgE and RAST tests. Exhaled and nasal NO was measured by chemiluminescence analyzer. There were 23 asymptomatic subjects (mean age 29.53yrs)and 16 with symptoms (29.63yrs, p=0.95); 9 early LAA, 7 LAA asthma. Exhaled NO was raised in those with LAA symptoms 17.97 ppb ± 1.24 (mean ±sem) compared with the asymptomatic subjects 6.08 ±1.15, p