Occupational asthma and rhinoconjunctivitis caused by senna

Occupational sensitization to senna is seldom reported. We describe a 21-year-old male atopic factory worker who developed IgE-mediated asthma and rhinoconjunctivitis 5 months after exposure to senna while he was working for a company manufacturing hair dyes. In the bronchial challenge test with senna, he exhibited a strong reaction. The skin prick test gave a 12-mm wheal reaction. The radioallergosorbent test (RAST) with senna was highly positive (33.6 PRU/ml, class 4), and could not be inhibited with pollens or foods. In protein staining with SDS-PAGE, two heavy bands were detected in senna at about 14 and 25 kDa, and two faint bands were visible at 19 and 21 kDa, In IgE immunoblotting with the patient's serum, one heavy band was detected at about 16 and four faint bands at 23, 25, 28, and 38 kDa. The patient became symptom free after he had changed his job within the same company.