Latex allergy in dentistry. Review and report of case presenting as a serious reaction to latex dental dam

Latex allergy may have severe consequences including development of anaphylaxis. This report describes a patient who underwent a reaction to latex dental dam manifesting as erythema, facial swelling and mild airway compromise. Restorative procedures under latex dental dam were performed under local anaesthesia on two occasions resulting in reactions of increasing severity. Following the first event the cause of the reaction was undetermined, but attributed to a possible allergy to local anaesthetic, and managed with corticosteroids and antihistamines. On a subsequent occasion the swelling was more severe, associated with difficulty in swallowing and mild airway compromise, and was managed as previously with adrenaline also being required. Latex allergy was subsequently confirmed.

The en 455-3 modified lowry assay does not yield a reliable estimate of the allergenicity level of latex gloves with low total protein content

BACKGROUND

Estimation of the allergenicity of latex gloves by measurement of total extractable protein content with the modified Lowry method is not satisfactory. Therefore, complementary methods that are accurate, sensitive, and clinically relevant are needed. The Competitive Immunoassay for Antigenic Latex Proteins (CIALP) method described in a previous study could be a reliable complementary method for estimating the allergenicity of latex gloves.

MATERIAL/METHODS

Extracts from 62 powdered or powder-free gloves (16 surgical and 46 examination) were tested by the EN 455-3 modified Lowry assay, IgE-inhibition, and CIALP. The results were compared with those from 36 glove extracts reported in a previous study.

RESULTS

Significant correlations were observed between CIALP, IgE-inhibition, and the Lowry assay for the 62 glove extracts (r between 0.79 and 0.87; p<0.001), mostly rich in proteins. After inclusion of results from the previous study, significant correlations between the three methods were again observed (r between 0.76 and 0.90; p<0.001). However, there was no correlation between CIALP or IgE-inhibition and results of the Lowry assay for gloves that had a total protein content <50 micro g/g of glove. Furthermore, 15/16 extracts with undetectable total proteins were positive in both the CIALP and IgE-inhibition methods.

CONCLUSIONS

The modified Lowry assay alone is useful for estimating the allergenicity of latex gloves when the total protein content is >/=50 micro g/g of glove. For gloves with a total protein content <50 micro g/g of glove, complementary methods such as CIALP are necessary.

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.

Tolerance and effects on skin reactivity to latex of sublingual rush immunotherapy with a latex extract

BACKGROUND

Specific immunotherapy could be a therapeutic tool for the increasing problem of sensitisation to Natural Rubber Latex (NRL).

OBJECTIVE

To investigate the tolerability of SLIT for Latex and its effects on skin reactivity.

METHODS

Twenty-six patients (mean age 35.5 years) with an average history of 7.5 years of cutaneous symptoms plus respiratory symptoms (23/26) due to NRL were studied. All underwent rush sublingual therapy (4 days) with a standardized NRL extract followed by a 9-week maintenance treatment. Local and systemic adverse reactions were monitored throughout the treatment. Skin reactivity to NRL extract was evaluated before, during and at the end of the treatment by latex glove-use test, rubbing test and skin prick test.

RESULTS

All patients reached the maintenance dose. Out of 1044 administered doses, 257 (24.6%) produced adverse reactions from which 21.4% were local. Only 10.1% of cases required treatment, mainly with antihistamines alone (5.8%), with 2-agonists alone (0.8%) or associated to antihistamines and/or corticosteroids (2.7%). One patient was precautionary treated twice with adrenaline but completed the treatment without further problems. The glove-use test improved significantly after 5 days and 10 weeks of treatment (p = 0.003, p = 0.0004 respectively), whereas the rubbing test improved significantly only after 10 weeks of treatment. Doctor's assessments confirmed the results obtained with the glove-use test (p = 0.003 after 5 days, and p = 0.004 after 10 weeks) but not those obtained with the rubbing test. No change was detected for SPTs.

CONCLUSION

SLIT for NRL allergy is able to modify skin reactivity to NRL in days as assessed with methods reproducing HCWs normal exposure to the allergen. Tolerance of SLIT is better than tolerance reported for injective therapy with NRL, but the build up phase should be administered under medical surveillance until sufficient experience has been accumulated. The long-term effect of the treatment deserves further investigation.

Dermatitis artefacta?

A 35-year-old man presented with a 2-month history of intensely pruritic excoriated and crusted linear lesions on the dorsa of the left hand and left forearm (Fig 1). The patient had worked in construction for 2 years, and his job consisted mainly in covering the facades of buildings with cement. The patient was right-handed and used a black rubber glove as a protective measure only on his left hand (Fig 2). He reported that the lesions resolved partially during holidays and weekends and clearly flared in association with his work. There was no history of atopic dermatitis, drug use, or intolerance to metals, rubber, or fruits. On physical examination, linear excoriations with crusts were observed on the dorsa of the left hand, extending to the ventral and dorsal aspects of the forearm, involving the whole area that was in contact with the glove. Lichenified erythematous plaques and excoriations on the dorsal surface of the metacarpophalangeal joints and scaly lesions on the dorsal surfaces of the fingers were also present. On the palm, only discrete hyperkeratosis was seen. The right hand and forearm were free of lesions. He complained of intense pruritus when wearing the rubber glove and admitted to continuous scratching to relieve his discomfort, inducing the linear and excoriated lesions. Treatment with topical corticosteroids was initiated, with progressive resolution of the lesions.

Minimizing latex exposure and allergy. How to avoid or reduce sensitization in the healthcare setting

Healthcare professionals with long-term exposure to natural rubber latex products and patients who undergo multiple operations are at high risk for latex allergy. The clinical spectrum of this allergy ranges from self-limited contact urticaria to involvement of multiple organ systems in anaphylaxis. In this article, Dr Muller explores the roots of the latex allergy epidemic and offers insight into the manufacturing process of latex gloves. She also presents a clinical approach to prevent or ameliorate sensitization and manage allergic symptoms.

Prevalence of latex sensitization in health care workers of a general hospital in Palermo, Sicily

STUDY OBJECTIVE

To assess the prevalence of latex sensitization in a group of hospital employees in a general hospital.

DESIGN

Cross-sectional study on hypersensitivity to latex gloves among health-care workers.

SETTING

A general hospital in Palermo, Sicily.

PATIENTS

196 health-care workers answered a questionnaire about their case history of allergic diseases (i. e., rhinitis and/or asthma) and about symptoms after wearing latex gloves. All subjects were tested by skin prick test (SPT) with commercial latex extract and aeroallergens and had blood draw for total serum IgE and latex-specific IgE testing and glove-use test.

MAIN RESULTS

42% of the subjects who answered the questionnaire reported at least one symptom after wearing latex gloves. All symptoms were local, and none of the subjects reported systemic reactions. The most common symptom was itching, but none of subjects with only itching presented a positive SPT or specific serum IgE to latex. The SPT to latex was positive in 19 of 196 subjects (9.7%). Specific IgE to latex were found in 15/196 subjects (7.6%). Glove-use test was positive in 14/196 (7.1%).

CONCLUSIONS

The overall prevalence of latex sensitivity in health-care workers in our epidemiological setting is 7.1%. An accurate diagnosis must take in account the integration of in vivo and in vitro tests with previous history of allergic disease.

Desensitization to latex by percutaneous route

Latex allergy is a newly emerging problem. In the last decades its prevalence has increased progressively, especially among health care personnel and patients. Preventive measures have been suggested to reduce the risk of sensitization, but this is very difficult because of the ubiquity of latex products. Since only two clinical reports are available in the literature, suggesting that subcutaneous desensitizing treatments resulted in important side effects, we decided to attempt a desensitization through alternative routes. After having succeeded in carrying out sublingual desensitization, we report the case of a latex-allergic patient who successfully underwent percutaneous desensitization.

Advances in environmental and occupational disorders

The environment plays a crucial role in determining the development and expression of allergic disorders. Epidemiologic studies allow us to understand risk factors for allergic disease, which may lead to interventional studies to provide the evidence base for our clinical advice. Articles published in The Journal of Allergy and Clinical Immunology last year highlighted the relevance of mold exposure and environmental tobacco smoke as risk factors for the development of asthma and the expression of symptoms. The role of fitted carpets as a reservoir for house dust allergens was also challenged by data arising from this work. Occupational allergy is an important clinical and socioeconomic problem. A large body of work on latex allergy has been reported in the past year, demonstrating the impact of containment strategies on exposure to latex and the incidence of sensitization to latex. Other articles have explored the range of latex allergens to which patients are sensitized and the HLA associations of latex allergy. Two models of isocyanate sensitization were reported, providing some insight into possible mechanisms of isocyanate asthma and some clues for understanding nonallergic asthma. Environmental and occupational disorders are highly relevant to our readership, and the new Editorial Board hopes to encourage submission and publication of relevant articles in this area.

[A successfully treated case of intraoperative latex anaphylaxis during abdominal aorta aneurysm resection]

We experienced resuscitation from latex anaphylaxis induced by surgical gloves during elective abdominal aorta aneurysm resection in a low risk adult with latex allergy. The patient developed severe circulatory collapse 10 minutes after the start of surgery. Although administration of dopamine, norepinephrine, and a large amount of fluid could not normalize this circulatory collapse, but addition of famotidine and chlorpheniramine could restore blood pressure. After resuscitation, we decided to postpone the operation. The re-operation was planned in the latex free setting one month later. All products, containing latex, had been excluded from operating room one day before the re-operation, and the patient entered operating room earlier than other patients to avoid latex-polluted powder from surgical gloves of other staffs. Y-shaped graft replacement was performed, and the perioperative course was uneventful. Latex is the second leading cause of intraoperative anaphylaxis, and the high-risk cases could be easily detected through the questionnaires, focusing on latex and other tropical fruits allergy. Moreover, because it is easy to get latex-free products, we recommend that a set of latex free products should be prepared at least for a high-risk case of latex allergy.

Prevalence and methodology of evaluation for latex allergy among allergists in the United States: results of a cross-sectional survey

BACKGROUND

Natural rubber latex allergy is a potentially life-threatening, Type I, immediate allergic reaction. Despite great strides in identification of high-risk groups, methods for diagnosis remain limited in the United States.

OBJECTIVE

The objective of this study was to estimate the prevalence of evaluation for latex allergy and methodologies used by allergists in the United States.

METHODS

A cross-sectional survey of all US Fellows of the American Academy of Allergy, Asthma and Immunology was conducted.

RESULTS

Of 1,239 questionnaires mailed, 519 (42%) were returned. Ninety-five percent of responding allergists reported evaluating patients for latex allergy. RAST and skin prick testing were the most commonly used tests. Sixty-two percent of respondents reported performing prick testing for latex allergy, with those in academic practices significantly more likely to do so. Whereas respondents practicing in the Northern United States were significantly more likely to evaluate for latex allergy than those in the Southern United States, no associations were found between practice location and prick testing for latex allergy. There was no association between practice type and evaluation for latex allergy. Only 6% of allergists reported ever witnessing a patient with anaphylaxis during latex allergy testing.

CONCLUSIONS

Almost all responding allergists evaluated patients for latex allergy, with approximately two thirds utilizing prick testing.

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.

Clinical and laboratory-based methods in the diagnosis of natural rubber latex allergy

The accurate diagnosis of hypersensitivity to natural rubber latex is the initial step in the effective management of individuals with latex allergy and in ensuring the quality of epidemiologic studies. The diagnostic algorithm used in the evaluation of an individual with suspected latex allergy begins with a comprehensive clinical history during which risk factors (atopy, food allergies, hand dermatitis) and temporal relationships between symptoms and natural rubber product exposure are identified. If type IV hypersensitivity is suspected because of the delayed nature (hours to days) and confinement of symptoms to the skin-latex product contact areas, patch testing can be conducted to confirm the presence of activated T cells with specificity for rubber chemicals. If type I hypersensitivity is suspected because of ocular, upper and lower airway, and/or systemic symptoms that have rapid onset (minutes) after a definable latex exposure, a confirmatory skin or blood test for IgE antibody may be conducted to verify a state of sensitization within the individual. The definitive diagnosis would then be made only after consideration of the individual's clinical history and confirmatory in vivo and/or in vitro laboratory test results. If discordance remains between highly convincing latex-associated symptoms as identified in the history and repetitively negative confirmatory IgE antibody test results, then one of several types of in vivo provocation tests may be performed for adjudication. This overview examines the current state of the art in both in vivo and in vitro diagnostic methods for latex-specific IgE antibody detection in skin and blood. The performance, advantages, and limitations of each diagnostic method are compared.

Epidemiology of latex sensitization and allergies in health care workers

Although it is often claimed that health care workers are at increased risk of latex sensitization and type I allergies, there has been no systematic analysis of the epidemiologic studies that are relevant to this conclusion. A systematic analysis of the epidemiologic literature found that, in the past 14 years, there have been 48 epidemiologic studies of type I latex allergy among health care workers. Of these, 2 cohort studies estimated the incidence of latex sensitization by skin prick testing at between 1% and 2.5% per year. Neither compared the risk to that in the general population. The prevalence of sensitization in health care workers varied between 0% and 30%, yet this large variation was unexplained. Increased risk of sensitization was not clearly associated with the duration of work in health care, the time spent wearing latex gloves, the frequency of exposure, the specific job categories, the use of powdered versus nonpowdered latex gloves, the use of latex versus nonlatex gloves, or any measurements of ambient exposure to latex proteins. The epidemiologic studies do not support a conclusion that health care workers are at clearly increased risk of latex sensitization or type I allergies compared to other occupations in the United States. The role of latex gloves in causing latex sensitization and type I allergic symptoms remains poorly defined because of the inconsistent results across studies. Future epidemiologic studies are needed that include measured exposures to latex antigens, that compare health care workers to appropriate referent groups, and that address confounding by atopy, age, sex, and race.

Anaphylactic reactions during surgical and medical procedures

The most common agents that are responsible for intraoperative anaphylaxis are muscle relaxants. However, latex accounts for a significant number of these reactions, and the incidence of intraoperative anaphylaxis caused by latex is increasing. It is now probably the second most important cause of intraoperative anaphylaxis. Following muscle relaxants and latex are probably antibiotics and anesthesia induction agents. Other agents that are responsible include colloids, opioids, and radiocontrast material. However, they account for less than 10% of all reactions. The clinical manifestations of intraoperative reactions differ from those of anaphylactic reactions outside of anesthesia. Cutaneous manifestations are far less common; cardiovascular collapse may be more common. The diagnosis can be made more difficult because patients cannot express symptoms. There is a paucity of cutaneous findings; the patient is draped, and concomitantly administered drugs may alter the manifestations. These additional drugs can also complicate therapy. There are populations who are at-risk for anaphylaxis to latex during surgical procedures: individuals with a genetic predisposition (atopic individuals), individuals with increased previous exposure to latex (eg, anyone who requires chronic bladder care with repeated insertion of latex catheters or chronic indwelling catheters), health care workers who are exposed to latex mainly by inhalation, and possibly patients who have undergone multiple surgical procedures and therefore have been exposed to latex intravascularly and by catheterization on a number of occasions. It has been shown that pretreatment with antihistamines and corticosteroids that are used successfully for the prevention of reactions to radiocontrast material are not as effective in the prevention of anaphylactic reactions to latex. Therefore, the major emphasis has been on prevention. The key elements of prevention include an adequate history, testing for latex allergy in high-risk patients, preadmission measures, and the establishment of a "latex-free environment" while the individual is hospitalized. This is particularly important in the operating and recovery rooms.