A woman presented work-related rhinoconjunctivitis due to inhalation of pepsin used in a slaughterhouse. Prick tests and conjunctival challenge were positive to pepsin. Serum specific IgE to pepsin was 5.58 kU/L and an IgE-binding band of 43 kDa was detected in SDS-PAGE Immunoblotting. Rhinoconjunctivitis improved clearly when the patient was assigned to another place without contact with pepsin. Pepsin has been previously reported to cause occupational allergic asthma on three occasions. As far as we know, this is the first reported case in which an IgE-immunoblot has been performed.

Key words: enzymes, occupational rhinitis, pepsin A