Acute anaphylaxis resulting from routine patch testing with latex

The Importance of Education When Patch Testing

Education is the keystone of successful management of allergic contact dermatitis. This article outlines practical tips to manage patients' expectations of the patch test process and understand their results. The considerations are outlined in a stepwise fashion from before, during, and after patch testing. Resources for patient information are highlighted, and an update on provider education is also included.

Occupational allergies caused by latex

Allergy to natural rubber latex is an important cause of occupational allergy in healthcare workers. Disposable medical gloves are the major reservoir of latex allergens, particularly powdered gloves, in healthcare delivery settings. Diagnosis of latex allergy requires a history of exacerbation of cutaneous, respiratory, ocular, or systemic signs and symptoms after exposure to natural rubber latex products; and evidence of sensitization by patch testing, skin testing, measurement of latex-specific IgE antibodies, or challenge testing. Optimal management of latex allergy involves education concerning cross-reacting allergens, reduction of cutaneous or mucosal contact with dipped rubber products, and minimization of exposure to latex aeroallergens in work environments.

Latex hypersensitivity: relationship with positive prick test and patch test responses among hairdressers

BACKGROUND

Natural rubber latex is a frequent cause of IgE-mediated allergy in hairdressers; but a non-IgE-mediated allergy to latex proteins can also occur. Sixty-one hairdressers, reporting latex glove-related symptoms, were enrolled in the study.

METHODS

They were evaluated for latex allergy by assessment of serum specific IgE and skin prick tests. Patients were patch tested to a rubber additive series and to latex. Proportions were compared by one-tailed Fisher's exact test; mean values of continuous variables were compared by Student's t-test.

RESULTS

A diagnosis of IgE-mediated latex allergy was made in 11 (18%) hairdressers; patch tests with rubber-related antigens were positive in 24 (39.3%) subjects. The most positive patch tests were those with para-phenylenediamine (33%). Two hairdressers (3.3%) showed delayed reactions to the latex sample. Hairdressers with IgE-mediated latex allergy were older and presented a personal history of atopy and local hives after exposure to latex; they were more likely to have a positive response to other allergens on prick or patch testing.

CONCLUSIONS

Our study demonstrates a certain number of false-positive and false-negative results when reported symptoms of possible latex sensitivity were compared to prick and CAP tests to latex, indicating the problems of relying solely on self-report.

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.