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

Avoiding allergic contact dermatitis in patients with venous leg ulcers

The management of venous leg ulcers is frequently problematic, usually as a result of the patient's existing co-morbidities, but often because of problems in skin management, such as hyperkeratosis or skin sensitization and resulting contact dermatitis. Good leg ulcer management practice includes skin care, protection from excessive exudate and from potential sensitisers. This article explores how the practitioner can recognize allergic contact dermatitis in a patient with a venous leg ulcer and avoid the use of avoid potential skin sensitizers during management.

Allergic contact dermatitis from natural rubber latex in atopic dermatitis and the risk of later Type I allergy

The aims of the study were to assess whether contact dermatitis in children could be due to a delayed hypersensitivity reaction to natural rubber latex (NRL) and to define risk factors for later occurrence of Type I hypersensitivity to this allergen. Among 1800 children investigated for contact dermatitis, 55 were referred on suspicion of rubber allergy and had patch tests to NRL, as well as prick tests and blood tests for specific immunoglobulin E (IgE). A 2-year follow-up was then carried out. Delayed hypersensitivity to NRL was confirmed in 32 children. Patch testing with NRL proved to be positive, and clinical improvement confirmed the diagnosis and relevance of patch tests. 30 of these 32 patients had associated atopic dermatitis (AD). Prick tests and blood tests for specific IgE to latex were negative at the time of diagnosis. A 2-year follow-up showed that 10 of 27 patients presenting initially with a positive patch test without associated Type I sensitization later developed immediate hypersensitivity. Children with AD are at high risk for allergy to NRL protein. Exclusion of this allergen should be strongly advised in atopics because of the dual risk of dermatitis and later evolution into severe Type I hypersensitivity.

[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.

Latex allergy: diagnosis and management

Latex allergy is an IgE-mediated immediate hypersensitivity response to natural rubber latex (NRL) protein with a variety of clinical signs ranging from contact urticaria, angioedema, asthma, and anaphylaxis. Major allergens include dipped latex products such as gloves and balloons. In highest risk for NRL allergy are patients with spina bifida, but health care workers and others who wear latex gloves are also at risk. NRL allergic patients may also react to fruits/foods, especially banana, kiwi, and avocado. Diagnosis is made by a positive latex RAST and/or skin prick test or challenge test to NRL. Allergen avoidance and substitution and the use of latex-safe devices including synthetic gloves (vinyl, synthetic polyisoprene, neoprene, nitrile, block polymers, or polyurethane) are essential for the affected patient. Accommodation in the workplace may include the use of powder-free, low-allergen NRL gloves or synthetic gloves. These preventive measures have significantly reduced the prevalence of reported reactions to NRL. Hyposensitization is not yet feasible.

A Review of Latex Sensitivity Related to the Use of Latex Gloves in Hospitals

Beginning in the 1980s, use of latex gloves to protect health care workers against exposure to blood and body fluids increased. Since then, the number of reported cases of latex sensitivity also has increased. Reactions to latex range from contact dermatitis to anaphylactic shock. Low-powder, powder-free, and non-latex gloves provide alternatives to protect health care workers from occupational latex exposure.

Occupational contact dermatitis. Recognition and management

Occupational contact dermatitis (OCD) represents 90 to 95% of all occupational dermatoses. The incidence rate of OCD is estimated to be around 0.5 to 1.9 cases per full-time worker per year. However, epidemiologic data are lacking and incidence is probably underestimated, especially in the US. Over the past 20 years, OCD has been the most frequently reported occupational disorder to German social insurance institutions. Critical factors in the management of OCD are recognition of clinical features, knowledge of allergens and irritants present in different occupational fields, knowledge of suitable protection, interpretation of patch test results, and awareness of medicolegal aspects. Management of OCD should be carried out by dermatologists and patch test clinics in cooperation with physicians specialized in industrial medicine. Individuals at high risk of OCD are hairdressers, dental laboratory technicians, other healthcare workers, construction industry workers, metal workers, leather and shoe manufacturers, florists and gardeners, and bakers, caterers, confectioners and cooks.

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.

Allergic contact dermatitis in dentistry

Allergic contact dermatitis (ACD) in dentistry may affect dentists and orthodontists, technicians, nurses and patients. Changes to dental practice in recent years have altered the reported frequencies of allergens causing ACD in both dental personnel and patients. Allergic contact dermatitis to medicaments, metals and glutaraldehyde were previously common allergens in dentistry; however, widespread adoption of rubber gloves by staff has resulted in a significant increase in ACD to glove allergens in both dental staff and their patients, while affording protection against the traditional allergens. Both public concerns about potential toxicity of metals in oral restorations and a greater demand for cosmetic dentistry, have resulted in greater use of acrylics and resins by dental personnel, exposing them to highly allergenic materials. Dermatologists need to be aware of the newer allergenic materials used in dentistry in order to correctly manage skin diseases in this high-risk group.

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.

Natural rubber latex allergy

Rubber is an important industrial and consumer product encountered in many household items and medical devices. Whereas the chemical additives used in its manufacture are well recognized as a cause of delayed-type hypersensitivity (allergic contact dermatitis), it is only during the past decade that immediate-type allergy to natural rubber latex (NRL) proteins (latex allergy) has emerged as a serious health issue. Frequent, prolonged wearing of NRL gloves, especially amongst health care workers, is a major risk factor for such sensitization. Latex allergy is now an important medical, occupational, medico-legal and financial problem, and it is essential that policies are developed to reduce it. Undiagnosed latex allergy is potentially very serious for patients. This article briefly overviews latex allergy with emphasis on the practical issues of diagnosis and management.

Patch testing with natural rubber latex

Immediate-type hypersensitivity to natural rubber latex (NRL) may be associated with chronic eczema, and it has recently been suggested that NRL should be used as a patch-test allergen. However, a standardized preparation does not exist, and experience of patch testing with this substance is extremely limited. The aims of our study were to investigate the patch-test response to different preparations of NRL amongst patients with suspected contact dermatitis. 608 patients were patch tested with a latex series which included wet and dry preparations of undiluted high-ammonia (HA) NRL and low-ammonia thiuram-containing NRL. Cutaneous reactions to 1 or more NRL patches were noted in 24 patients. None of these were strong allergic reactions (> +), and in 15 patients, the responses were only doubtful (?+). Positive patch tests were observed in 9 patients, and were probably due to concurrent thiuram allergy in 6. In the remaining 3 patients, the reactions had subsided by the 2nd reading and may have represented false positives. None of the patients showed consistent allergic reactions to all NRL patches, and most of the doubtful readings had resolved within 4 days, suggesting that they were irritant rather than weak allergic responses. Patch testing to dry HA latex was associated with the least number of reactions. We conclude that allergic patch test reactions to NRL are uncommon, and as reactions are usually weak and difficult to interpret, we suggest that patch testing with NRL should remain experimental until further studies have been undertaken.