Natural rubber latex allergy and asthma

Decreasing incidence of occupational contact urticaria caused by natural rubber latex allergy in German health care workers

BACKGROUND

The development of allergy to natural rubber latex (NRL) is a risk for health care workers. A regulation banning powdered NRL gloves was implemented in Germany in 1998.

OBJECTIVE

This study assesses the effects of this regulation on the development of occupational skin disease caused by NRL in health care personnel working in facilities insured by the German statutory accident insurance company, covering some 1.8 million insured health care workers.

METHODS

We reviewed the annual numbers of reported suspected cases of NRL-induced occupational allergies (mainly contact urticaria) from 1996 through 2002, as well as the number and type of gloves purchased in acute-care hospitals from 1986 through 2002.

RESULTS

The number of purchased nonsterile examination gloves increased by 1387% between 1986 and 2002. The purchase of powder-free NRL examination gloves exceeded that of powdered gloves in 1998. The incidence of suspected cases increased until 1998 and has since decreased by 79.9%. Most suspected cases (67.9%) were identified as occupationally caused.

CONCLUSIONS

Reducing the purchase of powdered NRL gloves is associated with a decrease in suspected and proved cases of occupational contact urticaria caused by NRL. Development of occupationally caused contact urticaria by NRL can be reduced by banning the use of powdered NRL gloves.

Recent developments in latex allergy

PURPOSE OF REVIEW

Immediate allergic reactions to natural rubber latex continue to be an important medical and occupational health problem. In this review we focus on progress made in understanding the significance of occupational exposure and epidemiology, risk groups, diagnosis and prevention of natural rubber latex allergy. We also discuss methods aimed at quantification of clinically relevant natural rubber latex allergens and studies on B-cell epitopes of major natural rubber latex allergens.

RECENT FINDINGS

Prospective studies have been published focusing on the prevention of natural rubber latex allergy. Efforts to identify and characterize new natural rubber latex allergens were continued in several research groups. The use of purified allergens or proteins produced by recombinant DNA technology was assessed in studies aimed at improving the diagnosis of natural rubber latex allergy as well as in developing quantitative methods for the measurement of specific natural rubber latex allergens. For the first time, conformational immunoglobulin E epitopes were identified in a major natural rubber latex allergen, hevein, using a novel chimera-based allergen epitope mapping strategy.

SUMMARY

Measures taken in health care to reduce exposure to natural rubber latex products seem to be effective in reducing the number of new sensitizations. A few new minor natural rubber latex allergens, probably important in allergen cross reactions, were identified, and some nonmedical natural rubber latex products were found to be potentially dangerous to natural rubber latex-allergic patients. Sensitive and specific immunoassays for quantification of clinically relevant natural rubber latex allergens in manufactured products were developed in some laboratories. These assays may eventually replace the nonspecific total protein measurement, currently advocated by health authorities in the indirect estimation of allergen amounts in natural rubber latex products. Knowledge about conformational immunoglobulin-binding B-cell epitopes of major allergens is expected to be helpful in designing optimal reagents to specific immunotherapy.

Latex hypersensitivity: personal data and review of the literature

Latex allergy is an increasingly common condition, because use of latex products is widespread. The reactions to latex manufactures can be classified as allergic and non-allergic, these are the most common. Latex proteins are responsible for immediate IgE-mediated hypersensitivity allergic reactions. Symptoms range from rhinitis, conjunctivitis and urticaria to anaphylactic shock. Chemical additives can cause allergic contact dermatitis. The clinical symptoms of latex allergy could arise from direct contact with latex products, but may also result from inhalation of airborne allergens. Subpopulations at particular risk include: atopics, children with spina bifida or individuals who required frequent surgical instrumentations, health care workers, and all persons who have regular contact with latex products. Diagnosis of allergy is based initially on history: search for specific serum IgE, skin prick test and provocation test may confirm the suspicion. The most effective strategy in the treatment of latex allergy is avoidance, however this is virtually impossible, given large number of latex products we encounter since childhood. In this paper we review the current state of knowledge concerning latex allergy, including the clinical spectrum, identified allergens, the cross-reactions regarding the latex-fruit syndrome, diagnostic procedures and preventive measures. Several personal data increase awareness on this issue.