Baker's asthma due to xylanase and cellulase without sensitization to alpha-amylase and only weak sensitization to flour

Background: The baking additives xylanase and cellulase were described as baking additives causing baker's asthma. It is not known whether monosensitization to these enzymes may occur. Methods: We present a case report of a baker with work-related asthma evaluated by skin prick test (SPT), enzyme-linked immunosorbent assay (EAST), immunoblot, EAST and immunoblot inhibition, and specific bronchial challenge. Fungal xylanase and alpha -amylase were measured by two-site enzyme immunoassays in products used by the patient at work. Results: Allergy to xylanase and cellulase was demonstrated by SPT, EAST, immunoblot and specific bronchial challenge (for xylanase only). No sensitization to alpha -amylase could be demonstrated, but there was a weak flour allergy as documented by EAST and immunoblot and a positive occupational-type challenge with high concentrations of rye flour. Four baking additives contained measurable amounts of fungal alpha -amylase and xylanase, without a correlation between these enzymes. Conclusions: We conclude that occupational asthma due to the baking additives xylanase and cellulase may occur without concomitant sensitization to a-amylase and only weak sensitization to flour. Copyright (C) 2001 S. Karger AG, Basel.