Asthma from inhalation of Triplochiton scleroxylon (Samba) wood dust

Abstract

The inhalation of wood dust may produce allergic rhinitis, asthma, or contact dermatitis in sensitized patients. We describe a patient with occupational asthma induced by the inhalation of samba (Triplochiton scleroxylon) wood dust. A specific bronchial provocation test was conducted, and the patient showed a significant decrease in forced-expiratory volume in first second (FEV1) after the inhalation of nebulized samba wood allergens. We suggest an IgE-mediated mechanism since the patient had a positive skin test and positive specific IgE determinations using an extract of samba wood. SDS-PAGE immunoblots revealed IgE binding to proteins with molecular weights of 17 kDa, 28 kDa and less intense binding to a band with an approximate molecular weight of 60 kDa. Two asymptomatic skin test-negative subjects, also occupationally exposed to samba, did not show any signs of bronchoconstriction when challenged with the samba wood extracts. We conclude that the occupational asthma suffered by this patient is related to sensitization and occupational exposure to samba wood dust.