Occupational asthma from natural rubber latex. Specific inhalation challenge test and evolution

Area of Science:

• Allergy and Immunology
• Occupational Health
• Respiratory Medicine

Background:

• Natural rubber latex (NRL) is a primary cause of occupational respiratory problems among hospital staff.
• Identifying and diagnosing NRL-induced occupational asthma is crucial for managing healthcare worker health.

Purpose of the Study:

• To detail the diagnostic methods, including the specific inhalation challenge (SIC) test, for occupational asthma caused by NRL.
• To analyze patient outcomes and prognostic factors over a six-year period.

Main Methods:

• Evaluated 19 patients with NRL-induced occupational asthma using symptom scores, medication use, skin prick tests, IgE levels, and respiratory function tests.
• Performed specific inhalation challenge (SIC) tests with latex in 12 patients to assess immediate reactions.

Main Results:

• All patients showed positive latex-specific IgE, skin prick, and conjunctival tests; SIC tests were safe and revealed isolated immediate reactions.
• Occupational asthma due to NRL presented with variable latency, often preceded by urticaria, rhinoconjunctivitis, and sometimes anaphylaxis.
• Prognosis was poor, with only 16% symptom-free; job changes were common, and symptom intensity and exposure duration correlated with outcomes.

Conclusions:

• Natural rubber latex (NRL) is a significant aeroallergen responsible for occupational asthma in healthcare settings.
• Minor symptoms like urticaria and rhinoconjunctivitis can precede the development of occupational asthma.
• The SIC test is a safe diagnostic tool, but occupational asthma from NRL generally has a poor long-term prognosis.