[Significance of exposure tests in diagnosis of occupational asthma]

Twenty-eight patients aged from 32 to 60 years, including 18 female and 10 male, were examined because of bronchial asthma suspicion. They were employed in different professions, but more of them worked as baker or nurse. An occupation time was from 11 to 32 years, but first symptoms of bronchial asthma were noticed after 7-28 (mean 14 yrs.) years of work. At all patients the exposure test (inhalatory challenge) with some substances selected by disease history was performed. This above mentioned substances were mechanically polluted in air to simulate an occupational circumstances. The exposure was persisted from 5 to 30 minutes, according to observed disease symptoms. Spirometric tests were performed in 2 and 30 minutes after exposure, but in baker group also in 4 and 8 hours. At 26 patients a decrease higher than 20% of starting values of FEV1 was determined. In most cases there were immediate reactions, and at baker group--dual reactions. At two examined subjects no response of bronchial tree was observed but only burning of mucosa and cutaneous pruritus. For this reason at this group a diagnose of allergy to examined substances was established. Other ones 26 patients were diagnosed as occupational bronchial asthma.