Specific immunotherapy with a standardized latex extract in allergic workers: a double-blind, placebo-controlled study.

BACKGROUND

Preventive measures have been proposed to reduce the risk of sensitization to natural rubber latex (NRL), but this is not always feasible.

OBJECTIVE

The aim of this study was to determine the efficacy and safety of specific immunotherapy with a standardized latex extract in sensitized workers.

METHODS

Twenty-four patients allergic to NRL with contact urticaria (n = 8) and rhinitis or asthma (n = 16) were included (16 in the active group and 8 in the placebo group). Treatment started in a cluster immunotherapy protocol, with injections every week for 3 months and then every other week for another 3 months.

RESULTS

Patients in the active group had significantly lower values than patients in the placebo group in skin terms of reactivity to NRL (P <.01), rubbing test results (P =.047), and latex glove use test results (P =.046) after 6 months of treatment. There were no significant differences between the active and placebo groups in symptom scores, use of medication, self-assessment, or methacholine test results either before or after treatment. Differences in nasal and bronchial symptoms during specific inhalation challenges (P = not significant and P =.05, respectively) were observed in favor of the active group. In the active group 32 systemic reactions were observed (8% of doses), mostly during the build-up period, being more frequent in patients with respiratory symptoms (P =.004). All reactions responded promptly to treatment.

CONCLUSION

Clinical efficacy was shown mainly on cutaneous symptoms, although an improvement in rhinitis and asthma symptoms was also observed during specific inhalation challenges. Latex-specific immunotherapy might be a useful approach for the treatment of latex allergy in sensitized workers.