Allergic contact dermatitis from latex rubber

[Latex allergy]

Latex allergy has become an increasing cause of morbility in the last few years and is now recognized as an international health problem. The prevalence of latex sensitization among the general population is less than 1 %. The groups at highest risk include healthcare workers, rubber industry workers, patients with a history of multiple surgical procedures, particularly children with spina bifida and urogenital abnormalities, atopic individuals, and patients with certain fruit allergies (especially kiwi, avocado, chestnut and banana). The molecular and immunological characteristics of several natural latex allergens have been identified. Symptoms range from contact urticaria to anaphylaxis. Diagnosis is based on clinical history and is confirmed by skin prick tests. Measurement of serum specific IgE to latex can also be useful. The best treatment is latex avoidance and substitution by other materials. However, because latex products are ubiquitous in medical and nonmedical devices of daily use, a latex-free environment is not easy to achieve. In some patients, immunotherapy could be an alternative.

Toxicological and immunological aspects of occupational latex allergy

Latex allergy continues to be an important occupational health problem as latex products are used increasingly worldwide, particularly in healthcare. Although there are few epidemiological studies on the incidence of latex allergy, there has been an increase in the number of case reports over the last 10 years and, based on skin-prick tests, estimates of prevalence of latex allergy in healthcare workers range from 2% to 17%. The allergic health effects arise either from the latex proteins, generally causing a type I immediate hypersensitivity reaction, or from the chemicals added to latex during processing, causing a type IV delayed hypersensitivity reaction. Clinical manifestations of latex allergy depend on the route of exposure and occur by direct contact either with skin or mucosa, or by inhalation. The diagnosis of latex allergy is based on the history, skin tests, serological tests and challenge tests. Thirteen latex allergens have been identified and isolated so far from natural rubber latex. They differ in their potential to elicit immunological responses in individuals allergic to latex and thus have been designated as major or minor allergens. In latex gloves, cornstarch powder used as a donning agent carries latex proteins, thereby increasing inhalational and mucosal exposure to latex proteins. There also appears to be a positive correlation between protein content and allergenicity of gloves. The use of powder-free, low-protein gloves is effective in reducing symptoms and markers of sensitisation. Alternatives to latex gloves, such as nitrile or vinyl gloves are available but may be inferior in respect to manual dexterity and biological impermeability.

Latex allergy: prevalence, risk factors, and cross-reactivity

There are few little exact epidemiological data on the prevalence and incidence of latex allergy, partly because the diagnostic tools are unsatisfactory and partly because the epidemiological study planning often does not fulfill criteria of good praxis. On the basis of present data, latex allergy in normal population is low, under 1%. Known risk groups such as health care workers, atopic subjects, people with hand dermatitis, and especially spina bifida patients show higher prevalence numbers. The common serological cross-reactivity between latex and a great number of different fruits and vegetables is bound to common plant pathogenesis-related proteins and storage proteins. Despite positive serological tests, only about half of NRL-allergic subjects have clinical symptoms after eating cross-reacting foods.

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.

Type IV hypersensitivity reactions to natural rubber latex: results of a multicentre study

BACKGROUND

Positive patch test reactions to natural rubber latex (NRL) have been interpreted as allergic or irritant by different groups. Additives to the NRL test solution have also caused positive reactions in previous studies.

OBJECTIVES

Five centres of the British Contact Dermatitis Group conducted a prospective study on the prevalence of type IV hypersensitivity to NRL, using ammonia-preserved NRL solution for testing.

PATIENTS AND METHODS

A total of 2738 consecutive patients were patch tested. Where clinically indicated, specific IgE was measured or a prick test done.

RESULTS

Twenty-seven patients (1%) had a positive patch test reaction to NRL, which was considered to be allergic and of current relevance in 19 (70%) patients. Fourteen of these also had a positive prick test or specific IgE. Thirteen patients (48%) were male, 19 (70%) atopic and 13 (48%) had eczema on their hands.

CONCLUSIONS

We conclude that delayed-type hypersensitivity to NRL is a problem for a proportion of patients with eczema, particularly on their hands, and that patch testing with ammonia-preserved NRL can be recommended to identify these patients. Patients with a positive patch test should be investigated for contact urticaria to NRL.

Occupational contact dermatitis in nurses with hand eczema

Occupationally related dermatitis is a common problem in nurses, who are exposed to a wide variety of allergenic and irritant substances. In a group of 44 nurses with hand dermatitis (40 female, 4 male), 18 were thought to have a predominantly allergic contact dermatitis, 15 an irritant dermatitis, 7 other form of eczema, 3 atopic dermatitis and one pompholyx. 10 of the 15 irritant cases were diagnosed as occupational. Of the 18 patients with allergic contact dermatitis, the allergens were thought to be occupationally relevant in 8 cases. In 6 of these 8 the dermatitis was due to natural rubber latex (3) or other rubber chemicals (3). 2 had additional evidence of immediate-type hypersensitivity to natural rubber latex (one was patch test allergic to latex, the other to thiuram mix). Natural rubber latex allergy, both delayed and immediate, is a significant problem, and nurses at risk should be tested for both types of hypersensitivity, as well as being patch tested to standard, rubber and medicaments series.

Health-care workers and latex allergy

Latex hypersensitivity can pose a threat to anyone, but health-care providers are among the high-risk groups for developing latex hypersensitivity. Latex hypersensitivity likely results from health-care workers' increased use of gloves following implementation of universal precautions. It is also believed that the antigenic load of latex gloves causes an increase in latex hypersensitivity resulting from massive production of gloves. Although there are many studies on the prevalence of latex hypersensitivity among health-care workers, there appear to be discrepancies, which may affect the different apparent prevalence. Testing for latex hypersensitivity raises another problem. Latex allergens cannot be identified specifically; therefore, there is no standard test or testing solution that can identify hypersensitive persons. Although latex glove hypersensitivity was first identified in the late 1970s, there remain many uncertainties associated with it; as a result, there is a growing concern among health-care providers. The authors offer several precautions to avoid the development of latex hypersensitivity.

The problems of rubber hypersensitivity (Types I and IV) in chronic leg ulcer and stasis eczema patients

The prevalence of Type I and Type IV hypersensitivity to rubber allergens in patients with stasis eczema and/or venous leg ulcers over an 18-month period was studied by prick and patch testing. Results from 109 patients were analysed. Positive patch tests were found in 71 patients (65%). Delayed-type hypersensitivity to rubber chemicals was found in 17 patients (15.6%). However, only 1 patient who had additional risk factors showed Type I hypersensitivity to natural rubber latex. We therefore conclude that, although Type IV hypersensitivity to rubber chemicals is relatively common in our patients, Type I hypersensitivity to natural rubber latex remains rare.

Latex allergy

Coined the next major health concern of the decade, allergy to natural rubber latex affects people routinely exposed to rubber products. Groups at highest risk include health care workers, rubber industry workers, and persons who have undergone multiple surgical procedures, especially those with spina bifida. Allergy to latex is a type I, immediate, IgE-mediated reaction, which can lead to anaphylaxis and death. Much of latex research is published in allergy journals. Dermatologists may not be aware of the prevalence, symptoms, risks, diagnosis, and treatment of latex allergy. These topics are the subject of this review. Research concerning antigenic proteins, as well as sources of latex alternatives, is also summarized. (J Am Acad Dermatol 1998;39:1-24.)

LEARNING OBJECTIVE

At the completion of this learning activity, participants should have a clear understanding of the history, biology, epidemiology, mechanism, clinical characteristics, diagnostic work-up, and treatment of latex allergy. Readers should also have a greater understanding of multiple potential allergenic latex proteins and their importance in preventing future latex-sensitization.

Latex: a cause of allergic contact eczema in users of natural rubber gloves

BACKGROUND

Latex is a common cause of contact urticaria in glove users. We recently found that 1.2% of patients attending a contact dermatitis investigation unit had delayed type hypersensitivity to latex as a cause of eczema.

OBJECTIVE

We reassessed the relevant contact allergens in users of natural rubber gloves with hand dermatitis. Particular emphasis was placed on allergens not included in the standard patch test series.

METHODS

Consecutive natural rubber glove users with hand dermatitis were investigated for the presence of contact dermatitis and urticaria.

RESULTS

One hundred seventeen consecutive patients were tested. The American standard series missed 34% and the European 40% of patients with positive patch test reactions to rubber related chemicals. Six percent of patients (20% of those with a positive reaction) demonstrated delayed type hypersensitivity to latex, often in the absence of other relevant contact allergens and contact urticaria to latex.

CONCLUSION

Latex is a relatively common cause of allergic contact eczema in the absence of contact urticaria. Latex should be included in a rubber series for screening patients with hand dermatitis who are glove users.