Inhalation challenge testing of latex-sensitive health care workers and the effectiveness of laminar flow HEPA-filtered helmets in reducing rhinoconjunctival and asthmatic reactions

J Allergy Clin Immunol. 1998 Dec;102(6 Pt 1):998-1004. doi: 10.1016/s0091-6749(98)70338-0.

Abstract

Background: There are few data relating latex aeroallergen concentrations to biologic responses in latex-sensitized persons.

Objectives: We sought to investigate acceptable latex aeroallergen concentrations below which latex-sensitive health care workers do not experience symptoms and to study the effect of high-efficiency particle arrest (HEPA)-filtered laminar flow helmets in preventing latex-induced symptoms.

Methods: Under challenge chamber conditions, latex-sensitive health care workers underwent 7 sequential inhalation challenge tests by donning and discarding either vinyl gloves (challenge 1), low latex-allergen powder-free gloves (challenge 2), or high latex-allergen powdered gloves (challenges 3 to 7) for up to 1 hour. Volunteers wore a laminar flow helmet during all challenges; HEPA filters in the helmet were in place only during challenges 3 and 4. Flow-volume loops, symptom scores, and latex aeroallergen concentrations were measured before and during each test.

Results: At 60 minutes, latex aeroallergen concentrations during challenges 3 to 7 (mean, 7600 ng/m3; range, 93 to 54,000 ng/m3 ) were significantly higher than during challenges 1 or 2 (mean, 65 ng/m3; range, nondetectable to 100 ng/m3 ) (P <.001). During challenges 5 and 6, mean maximum percent falls in FEV1 (-16% and -11%, respectively) were significantly greater compared with those measured during challenges 3 and 4 (-3% and -1%, respectively) (P =.03). Mean maximum change from baseline symptom scores during challenges 5 and 6 was significantly higher than that during challenges 3 and 4 (P =.006). During challenges with high latex-allergen gloves, 4 volunteers had reproducible FEV1 falls of 20% or greater at cumulative inhaled latex aeroallergen doses ranging from less than 100 ng to 1500 ng.

Conclusion: The laminar flow helmets were effective in reducing latex-induced symptoms. Only 1 volunteer exhibited a fall in FEV1 of 20% or greater after a cumulative inhaled latex aeroallergen dose of less than 100 ng, and no volunteer showed a decline in FEV1 after exposure to powder-free low allergen gloves.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Air Pollutants, Occupational / adverse effects
  • Allergens / adverse effects
  • Bronchial Provocation Tests / adverse effects
  • Bronchial Provocation Tests / methods*
  • Endotoxins / metabolism
  • Environment, Controlled*
  • Female
  • Filtration / instrumentation
  • Head Protective Devices*
  • Health Personnel*
  • Humans
  • Latex Hypersensitivity / diagnosis*
  • Latex Hypersensitivity / prevention & control*
  • Middle Aged
  • Pilot Projects
  • Prospective Studies
  • Single-Blind Method

Substances

  • Air Pollutants, Occupational
  • Allergens
  • Endotoxins