Lactase-induced occupational protein contact dermatitis and allergic rhinoconjunctivitis

Area of Science:

• Occupational immunology
• Protein biochemistry
• Dermatology

Background:

• Enzymes, like lactase, are known occupational allergens causing respiratory and conjunctival sensitization.
• Previous studies confirmed lactase-induced allergic rhinoconjunctivitis but lacked challenge test confirmation.
• Lactase-induced contact skin reactions and specific IgE antibodies were not previously reported.

Observation:

• A pharmaceutical worker experienced allergic rhinoconjunctivitis and protein contact dermatitis due to occupational lactase exposure.
• The patient showed positive prick tests, whealing in open application tests, and eczematous reactions in patch tests to lactase.
• Lactase-specific IgE antibodies were detected via immunospot and radioallergosorbent assays.

Findings:

• Confirmed lactase-induced occupational IgE-mediated respiratory and conjunctival sensitization.
• Demonstrated lactase as a cause of immediate (whealing) and delayed (eczematous) contact skin reactions.
• Identified lactase-specific IgE antibodies and characterized lactase-IgE binding fractions.

Implications:

• Lactase sensitization can lead to both respiratory/conjunctival symptoms and contact dermatitis in occupational settings.
• Highlights the importance of considering skin testing in addition to respiratory testing for lactase allergy.
• Suggests broader diagnostic approaches for occupational allergies to enzymes in the pharmaceutical industry.