Sensitization rate and risk factors for sensitization to digestive enzymes in hospital personnel

Background: Hospital personnel can be sensitized by the inhalation of digestive enzymes and develop occupational asthma and rhinitis. Our previous reports demonstrated a high prevalence of serum specific IgE antibodies to digestive enzymes in exposed subjects with work related symptoms. This is a follow up study 3 years after the first intervention to evaluate the change of the sensitization rate and risk factors in hospital personnel. Method: A total of 167 hospital personnel, including 25 pharmacists (higher exposure group) and 142 nurses (lower exposure group), in a tertiary hospital were enrolled. We also recruited 86 unexposed non-atopic healthy controls. The questionnaire contained items including the workplace, intensity of exposure, duration of employment, digestive enzyme-associated work related symptoms (WRS), and past history of allergic diseases such as bronchial asthma, allergic rhinitis, atopic dermatitis, chronic urticaria, and drug allergies. Skin prick tests (SPTs) using biodiastase, the most commonly prescribed digestive enzyme, and common inhalant allergens were performed. Serum specific IgE antibodies to biodiastase and porcine α-amylase were measured by ELISA. The total IgE level was measured by the immunoCAP system. Results: The prevalence of digestive enzyme-associated WRS was 36.0% in pharmacists and 4.2% in nurses. The sensitization rates in pharmacists using the SPT to biodiastase (37.5%) and serum specific IgE antibodies to biodiastase and/or porcine α-amylase (25.0%) increased over the previous report (both 16.7%). The sensitization rate in nurses using the SPT to biodiastase (9.6%) was similar to that of the previous report (9.6%), while the sensitization rate using serum specific IgE antibodies to biodiastase and/or porcine α-amylase (3.5%) decreased from that of the previous report (8.9%). Past history of atopic dermatitis (OR, 28.6; 95% CI, 4.1-200.4) and drug allergies (OR, 6.9; 95% CI 1.2-39.6) were found to be risk factors for the sensitization to digestive enzymes. Conclusion: The sensitization rate to digestive enzymes in pharmacists increased after the first intervention performed 3 years ago. The SPT to digestive enzymes would be more useful in the detection of sensitized subjects than the monitoring of serum specific IgE antibodies to digestive enzymes. Skin contact as well as inhalation could be a route for sensitization to digestive enzymes in hospital personnel.