Reference

BOHRF Original Authors' Main Conclusions

The original authors' main conclusions are taken from Abstract, Results and Discussion. They are decided upon by the authors of the BOHRF occupational asthma guidelines and form part of the guidelines.

Authors report a patient with presumed occupational asthma caused by exposure to toluene di-isocyanate (TDI). Variable airflow obstruction measured by peak flow rates (PFR), and symptoms of asthma reversed by salbutamol, occurred after natural exposure to TDI when methacholine bronchial responsiveness was well into the non-asthmatic range. The asthma occurred at the end of, or just after work, suggesting late asthmatic response. When the patient stopped work, asthma and increased diurnal variation of PFR recurred spontaneously until methacholine responsiveness returned into the normal range. Observations indicate that asthma can occur at a time when methacholine bronchial responsiveness is normal, providing the stimulus is strong enough. They further demonstrate that the magnitude and ease of bronchoconstriction relates to the degree of methacholine responsiveness.

BOHRF Associated Evidence Statements

The BOHRF occupational asthma guidelines state that this reference is associated with the following evidence statements