Occupational asthma caused by Ipe (Tabebuia spp) dust.

BACKGROUND Ipe is a resistant hardwood that contains naphtoquinones. It is easily found and frequently used in South and Central America. Naphtoquinones are skin sensitizers. OBJECTIVE To describe a case of occupational asthma related to Ipe wood dust. METHODS The patient was submitted to a clinical evaluation consisting of a respiratory symptom questionnaire, occupational history, serial measurements of lung function by spirometry, skin prick tests, patch tests, specific IgE and specific bronchial provocation tests to Ipe dust. RESULTS Serial lung function measurements showed sustained regression of obstruction following removal from exposure. Skin prick tests, but not patch tests, were positive to Ipe, and a specific bronchial challenge showed a late asthmatic reaction. Specific IgE search was negative. CONCLUSIONS Exposure to Ipe wood dust can lead to occupational asthma. The underlying mechanism should be investigated.