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.     

Prevalence of latex allergy and evaluation of some risk factors in a population of atopic children.

The aims of our study were to evaluate (1) the prevalence of natural rubber latex (NRL) allergy in an unselected population of atopic children; (2) the diagnostic efficacy of skin prick tests (SPTs) with latex extracts; (3) the correlation between positive SPTs to latex and risk factors such as atopy, fruit allergy, history of surgery cares or dental cares. We randomly enrolled 151 unselected atopic and 59 nonatopic children who underwent SPTs with common inhalant and food allergens, and SPTs with two different latex extracts. A clinical history concerning allergic history, symptoms after contact with latex objects or after ingestion of fruits or vegetables, dental and surgical treatments was obtained. Six of the 151 atopic children were positive to latex SPTs, but only one out of 59 nonatopic children was positive to latex SPTs. Concerning risk factors, 86% of children with SPT positive to latex were atopic, 71.4% had a clinical history of surgery, and none of them had undergone dental or orthodontic treatments. The prevalence of NRL sensitization in our unselected population of atopic children was 3.9%, but the prevalence of NRL allergy was 2.6%. Concerning NRL allergy, the sensitivity and the specificity of SPTs with latex extracts are high (1.00 and 0.98, respectively), as well as negative predicting value (1.00); the positive predictive value is low (0.70). We conclude that atopy, surgical treatments, and sensitization to foods cross-reacting with NRL are important risk factors for NRL sensitization. We have no data concerning dental or orthodontic cares.     

A new quantitative in vitro for the detection of latex-specific IgE antibodies

Immediate-type hypersensitivity to latex allergens has resulted in anaphylactic shock and death in numerous reported cases. The allergenic proteins of latex are contained within the natural rubber extract of Hevea brasiliensis and are eluted into the final product during the manufacturing process. The quantity and types of latex allergens found in different latex products depends on the manufacturing process. Not all of these allergens are available for use in the latex prick skin test, and as a result, such tests may not be conclusive. Furthermore, application of such allergens to the skin of undiagnosed hypersensitive individuals may have harmful effects on their health. Therefore, it is important to be able to utilize in vitro methods, which reliably identify latex allergy without placing hypersensitive individuals at risk. We have developed a relatively simple and new enzyme immuno-assay (EIA) method for the detection of latex allergy. This in vitro method is quantitative and allows for the classification of allergy to latex in a short time. In comparative studies, ninety-nine serum specimens with documented clinical history of latex allergy were tested by this method, and the results paralleled those of the skin prick test performed by an independent group. The data showed that the specificity and sensitivity of our assay approaches 97.5% and 100%, respectively. We conclude that, by using a simple assay, the detection of specific IgE to latex proteins may be valuable for screening individuals and for the diagnosis of allergy to latex.     

Latex allergy and fruit cross-reaction in subjects who are nonatopic.

Since the first case reported in 1927, latex allergy has attracted the attention of allergists including its capacity to cross-react with fruits. To evaluate the frequency of sensitivity to some fruit allergens shown to cross-react with latex, we evaluated 82 patients (43 men and 39 women, aged between 18 and 45 years) with latex allergy. All patients underwent skin tests with various fruit extracts that potentially cross-react with latex. Only patients with negative prick tests successively underwent prick-by-prick tests with fresh fruits. Thirty-nine of 82 patients (47.5%) were found to have positive skin tests. Prick tests with fruit extracts were positive in 28 patients (kiwi, 21 patients; banana, 17 patients; avocado, 8 patients; and papaya, 3 patients), and the prick-by-prick test had positive results in 11 patients (kiwi, 7 patients; banana, 4 patients; and avocado, 3 patients). In our experience patients with latex allergy are at a high risk of sensitization to some fruits and they often develop allergic reactions, even severe ones, after eating them; for this reason fruit sensitization should be taken into consideration when investigating patients allergic to natural rubber latex.     

Latex allergy in children: a follow-up study

BackgroundNatural rubber latex allergy is an important health problem. Multiple contacts with latex in childhood are a risk factor. Many aspects of this disease are still unknown, one of which is the clinical outcome of these children. The aim of this study was to evaluate the clinical and epidemiological features of latex allergy and compliance with latex avoidance instructions in allergic children.Material and methodsSeventeen consecutive patients with a history of latex allergy, fruit allergy or chronic urticaria were selected. The patients underwent a skin prick test and determination of specific-IgE to latex at the start and at end of the study (median follow-up: 3 years). At diagnosis, patients with a positive result to one of the tests and a clinical history of latex allergy were considered allergic; patients with a positive test but without a clinical history suggestive of allergy were considered sensitized. These children were given latex avoidance instructions.ResultsEleven children (64.7 %) were classified as allergic and 6 (35.3 %) as sensitized. Five patients had undergone latex-free surgery after diagnosis without incident. During follow-up, 11 patients (8 allergic and 3 sensitized) had contact with latex. Contact occurred in the home in 10 children, and all were symptomatic. Specific-IgE levels to latex at the end of the study were significantly higher in patients who had contact with latex during the follow-up period than in those without latex contact.ConclusionsStrict compliance with latex avoidance instructions is essential both inside and outside the hospital. Greater emphasis should be placed on reducing latex exposure in the home and school environments, as such contact could maintain positive IgE-antibody levels.     

Intraoperative anaphylactic shock in a child with no history of type I hypersensitivity

Natural rubber latex is the second most implicated agent in intraoperative anaphylactic reactions. This report describes a case of intraoperative anaphylaxis occurring in a non-atopic fourteen-year-old girl undergoing multiple surgical procedures, but without spina bifida, in which latex surgical gloves were the main culprit for the anaphylactic reactions. Clinical manifestations of an anaphylactic reaction were also experienced during the examination of the possible cause of intraoperative anaphylaxis by skin prick testing with a latex allergen extract. Skin tests with anesthetics were negative. Specific IgE to latex was positive at 92.9 kUA/L (class 5). The molecular basis for the reported intraoperative anaphylaxis was ascribed to three low-molecular mass latex allergens (10-15 kD) detected in the brand of latex surgical gloves used during the operation. Given the potential of a dramatic outcome, latex allergy testing as a regular preoperative measure may contribute to the reduction of anaphylactic reactions during surgical interventions.     

Natural rubber latex allergy: a problem of interdisciplinary concern in medicine

In the past 10 years, IgE-mediated allergy to natural rubber latex has become a significant health problem in industrialized countries, especially among health care workers, patients with congenital malformations, and children with a history of multiple surgical interventions. Curative treatment inducing immunological tolerance in formerly sensitized patients is experimental and not yet generally available. Therefore, it is important to be aware of the seriousness of latex allergy and to understand the risk factors leading to this allergy. Preventive measures are needed to decrease the incidence of natural rubber latex sensitization. This article gives a brief review of the current state of knowledge concerning latex allergy, including a definition of latex, epidemiological data, identified allergens, the clinical spectrum, diagnostic procedures, cross-reactions, preventive measures, the legislative background, and economics.     

Latex allergy: Review of recent advances

Latex allergy is an IgE-dependent immediate hypersensitivity reaction to latex proteins. Risk factors for latex allergy are contact with latex products and atopy. Children who undergo multiple surgical procedures and healthcare workers are the major groups at risk. Powdered latex gloves are an important source of sensitization. Preventive measures are leading to reduction in latex sensitization and allergic reactions. The prevalence of latex allergy in the general population may be as low as 0.1%, whereas the frequency of latex sensitization is reported to be 7%; this may be due to cross-reacting antipollen IgE. The most important latex allergens have been purified, and some have been cloned and sequenced. Many latex-allergic patients are also allergic to common plant-derived aeroallergens and foods. The structural and biologic relationships among plant-derived food allergens, including latex, explain these clinically important cross-reactions.     

New insights on latex allergy diagnosis and treatment.

Because of widespread latex manufacturing in the last decades, exposure to latex has become ever greater, as has the incidence of latex allergy among the general population as well as the high-risk groups. Clinical manifestations range from local reactions (edema, itching, erythema, and papulae), rhino-conjunctivitis, asthma, pharyngeal edema, to severe systemic reactions such as anaphylactic shock (from parenteral exposure especially during medical examinations or surgical procedures). Diagnosis is formulated on the basis of the personal history and an accurate allergological evaluation. Patients usually have a history of food intolerance or adverse reactions during medical or surgical procedures, which are believed to be the result of anesthetics or other drugs. In vivo tests are prick and patch tests and challenge tests. Challenge tests (nasal, conjunctival, bronchial, intravaginal, sublingual, oral, and cutaneous tests) are important for confirming the diagnosis, for evaluating a patient's response to the different kinds of latex exposure, and for verifying the effects of desensitizing treatments on the various organs involved in latex allergy. The most important in vitro test is the specific anti-natural rubber latex IgE assay. The only effective resolution to the latex allergy problem seems to be desensitization. The criteria of effectiveness are the capability to use latex items, to undergo medical examinations (even invasive), and to remain in an environment where latex particles can be inhaled (such as surgical departments), without symptoms. The first attempts were performed by subcutaneous administration of latex, but this protocol seems to be delicate to perform because of the side effects. Two different alternative methods (percutaneous and sublingual) were successfully performed and proved to be safer and more effective, even though further studies on a larger group of patients are needed.     

Allergic contact dermatitis to synthetic rubber following breast augmentation

Allergic reactions associated with silicone injection and implant were examined in a 50-year-old woman with a granulomatous reaction following breast silicone-gel prosthesis rupture who developed a delayed hypersensitivity to rubber compounds. Patch tests with SIDAPA, dental, and rubber series as well as open tests with latex, silicone and non silicone tubes, open application test with silicone gel, and skin prick test for aero and food-allergens were performed. Total and specific serum IgE measured by CAP-FEIA. Skin tests revealed a delayed-type hypersensitivity to thioureas, thiuram mixture and platinum. Specific IgE to natural rubber latex were found. Allergic contact dermatitis from thioureas, thiurams and platinum might be under-diagnosed, as they are not tested as part of the standard patch test series. Clinicians should consider this diagnosis in patients submitted to several cosmetic treatments.     

Prevalence of IgE-mediated allergy to latex in hospital nursing staff

Abstract Background: IgE-mediated hypersensitivity to latex proteins has become a significant clinical problem over the last decade. Nursing and medical staff are at risk because of their occupational exposure to latex.
Aims: To determine the prevalence of type I hypersensitivity to latex allergens in the nursing staff of an Australian hospital.
Methods: A questionnaire which asked about symptoms associated with the use of latex gloves was completed by 140 nurses working in the Alfred Hospital (72 in general medical wards, 68 in intensive care units). Skin prick tests with eluates of five different types of latex glove as well as common aeroallergens (rye pollen and house dust mite) and banana extract were performed.
Results: Thirty-one nurses (22%) were skin prick test positive to at least one of the five latex glove eluates. All of these nurses were atopic, having positive skin prick tests to rye pollen or house dust mite. Symptoms of local dryness, itch and erythema associated with glove use were reported by more than half the study group, but not more frequently by those who were skin prick test positive to latex. Urticaria associated with glove use was reported more frequently by those with positive latex skin prick tests (13% vs 4%, p=0.05). Eighty-seven per cent of the nurses who were latex skin test positive were also positive to banana extract.
Conclusions: IgE-mediated hypersensitivity to latex is common in nurses working in an Australian hospital. Glove associated symptoms were frequently reported, but in most cases the symptoms were more typical of irritant or contact dermatitis rather than type I hypersensitivity reactions. However, the extent of subclinical sensitisation to latex found in this study suggests that symptomatic latex allergy is likely to emerge as an increasing problem for nursing staff in this country.     

Latex allergen sensitization and risk factors due to glove use by health care workers at public health units in Florianopolis, Brazil.

BACKGROUND: Natural rubber latex allergy is a "new" illness whose prevalence has reached epidemic proportions in highly exposed populations such as health care professionals. OBJECTIVE: The aim of the study was to evaluate the frequency of reactions to latex and risk factors due to glove use in health care workers (HCW) in Florianopolis, Santa Catarina, Brazil. METHODS: We evaluated latex-related allergy in 260 HCW by means of a questionnaire, skin prick tests (SPT) and serum latex specific IgE antibody levels. The subjects were divided into two groups depending on level of exposure to latex gloves. Comparisons were made between the different variables and a risk score was calculated using logistic regression analysis. RESULTS: Glove-related symptoms were observed in 57% of 140 HCW. Significant differences between HCW and control groups were found for the following symptoms: contact dermatitis (P < .0001), cutaneous rash (P < .0001), asthma or allergic rhinitis (P < .0001), symptoms associated with toy balloons (P < .0001), airborne glove powder causing latex allergen reaction (P < .0001), food allergy (P < .0001), fruit allergy (P < .0001) and multiple surgical interventions (P = .0052). Contact dermatitis and anaphylaxis were the main problems, with a high risk factor for the development of latex allergy. Logistic regression analysis showed a significant positive association between the risk of latex allergy and those subjects who reported more than 4 positive answers on the questionnaire (including SPT) (odds ratio 6.8; 95% confidence interval 0.7-60.3). No latex-related allergy symptoms were reported by the control group. Serological latex specific immunoglobulin (Ig) E antibody levels were negative for both groups. CONCLUSION: It is essential to recognize which professionals are sensitized to latex in order to provide appropriate treatment and to establish adequate prevention.     

Allergic reactions occurring during anaesthesia: diagnostic approach

Anaphylactic and anaphylactoid reactions to anaesthetic and associated agents used during the perioperative period have been increasingly reported during the last 3 decades. The frequency of life-threatening hypersensitivity reactions occurring during anaesthesia has been estimated to vary between 1/1.000 and 1/25.0000 procedures, with muscle relaxants being involved in almost three quarters of the cases. The mortality from these reactions is in the range of 3-6%. Nowadays, natural rubber latex also accounts for a significant number of perioperative anaphylaxis, particularly in children. Clinical manifestations do not allow to differentiate between IgE-mediated anaphylaxis and anaphylactoid reactions resulting from non-specific mediator release. Successful management of these patients requires multidisciplinary approach and includes prompt recognition and stabilisation of the acute event by the attending anaesthetist, determination of the responsible agent(s) with avoidance of subsequent administration of incriminated compound(s). The latter is based upon correct identification of the responsible drug and potentially cross-reactive compounds by the allergist and requires a detailed review of the anaesthetic report as well as appropriate in vitro and in vivo allergy tests. At present, the overall performance of skin tests makes them the "gold standard" for diagnosis of muscle relaxant-induced perioperative hypersensitivity reactions. In addition, given their good negative predictive value, skin tests have been proven to be a useful tool to tailor the appropriate therapeutic alternative. For other compounds diagnosis is more difficult but newer techniques such as analysis of in vitro activated basophils can be helpful.     

Latex allergy among operating room personnel in Turkey.

This study was performed to evaluate the prevalence of latex allergy among health care workers in Turkey, as well as to compare the medical histories with the skin test results and investigate the risk factors. Using a 1/100 weight/volume commercial skin prick test (SPT), we investigated latex sensitization in 206 health care workers who regularly use latex products. One hundred atopic and 100 nonatopic patients without occupational latex exposure were also examined as control groups. Latex SPTs were positive in 10 health care workers (9.22%), whereas none of the control patients was found to have positive SPT to latex. Health care workers were divided into two groups based on the latex SPT results. There was no significant difference between the latex SPT-positive and -negative health care worker groups according to age, sex and total exposure time to latex. In the latex SPT positive group, daily exposure time and daily glove use were significantly higher (p <0.05). The symptoms related to latex products were limited to hands and itching was present in all, however, erythema was found in 68.4%, and contact urticaria in 52.6% in the latex SPT positive group. These symptoms in the latex SPT negative health care group were 21.4%, 14.4%, and 1.6%, respectively (p <0.0001). History of allergic rhinitis, bronchial asthma and conjunctivitis were also higher in the SPT-positive group (p <0.05). Additionally, we found sensitivity to house dust mites and/or grass pollens in seven cases of latex allergy. Patch tests with rubber additives were positive in five out of 42 medical care workers. Two surgeons were found to have both type-I hypersensitivity to latex and type-IV hypersensitivity to rubber additives. Our results suggest that the frequency of latex allergy is higher in the atopic health care workers with a high exposure to latex, and that SPT is a sensitive, safe, cheap and easy method of testing the diagnosis of latex hypersensitivity.     

Follow-up study of latex-allergic health care workers in Japan.

BACKGROUND: While many cases of latex allergy have been reported in Japanese health care workers (HCWs) since 1992, there have been no follow-up studies after removing latex from the workplace. We had previously replaced all working environment latex gloves and latex products with low-allergen or non-latex products. The purpose of the investigation was to evaluate the benefits of the latex allergy countermeasures that were taken in our hospital, and the effects of life guidance education. METHODS: We investigated 16 latex-allergic HCWs in our hospital. We gave them a detailed questionnaire and tested them by a skin prick test (SPT) with latex extract and specific IgE antibodies against latex using the Pharmacia CAP RAST system, RAST FEIA. We compared these results with earlier results from the time of diagnosis. RESULTS: According to the questionnaire, none of the HCWs had changed their work habits, though all were avoiding the use of latex products as much as possible. Of the 16 patients, 81.2% were eating foods for which cross reactivity with latex has been reported. However, the foods had not induced severe allergic symptoms. In the SPT, 62.5% of scores decreased and 81.2% of patients had decreases in specific IgE antibody levels. CONCLUSIONS: After avoiding latex products and following our educational suggestions, the patients' allergy symptoms had generally improved. This indicates that our countermeasures against latex allergy were largely successful.     

Erythema multiforme-like eruption due to carbamates and thiuram

Report of a case of erythema multiforme-like eruption due to the use of rubber gloves. After several complementary studies, including epicutaneous and skin prick tests, we concluded that the eruption was secondary to sensitization to carbamates and thiuram. The main differential diagnosis in this case was allergic contact dermatitis to latex in natural rubber gloves. This entity is less frequent than might be expected, because it is usually due to intermediate chemical compounds used in rubber manufacturing, such as vulcanization accelerators; among of these latter compounds are thiurams and carbamates. Erythema multiforme-like eruption is a rare manifestation of contact dermatitis. Several cases have been reported, most of which have been due to contact with plants, metals or topical non-steroidal anti-inflammatory drugs. Its mechanism is still unclear, but it seems to be a type IV hypersensitivity reaction.     

Allergie au latex : pertinence des mesures d’éviction

Complete latex avoidance is the most effective approach for treatment of latex allergy. Alternatives to latex gloves and other articles include chemical processes as well as synthetic rubber or other synthetic materials. These may be suited for certain uses only, depending on their respective physical properties. Global preventive strategies are based on current knowledge and a common-sense approach to minimizing latex allergy. Undue latex exposure should be reduced by the use of non-latex materials when there is little potential for contact with infectious agents. When latex is required, reduced-protein, powder-free latex gloves must be chosen. Education and information programs, improvement of ventilation procedures, frequent cleaning of contaminated areas, and training devices about latex allergy are usually recommended. However, detection of high-risk patients or workers must be discussed in relation to the background.     

Prevalence of food allergy in 137 latex-allergic patients.

There have been reports of increased prevalence of certain food allergies in patients with Type I latex allergy (LA). A detailed food allergy history was obtained from 137 patients with LA. Latex allergy was defined by positive history of IgE mediated reactions to contact with latex and positive skin prick test to latex and/or positive in vitro test (AlaSTAT and/or Pharmacia CAP). Food allergy was diagnosed by a convincing history of possible IgE mediated symptoms occurring within 60 minutes of ingestion. We identified 49 potential allergic reactions to foods in 29 (21.1%) patients. Foods responsible for these reactions include banana 9 (18.3%), avocado 8 (16.3%), shellfish 6 (12.2%), fish 4 (8.1%), kiwi 6 (12.2%), tomato 3 (6.1%), watermelon, peach, carrot 2 (4.1%) each, and apple, chestnut, cherry, coconut, apricot, strawberry, loquat, one (2.0%) each. Reactions to foods included local mouth irritation, angioedema, urticaria, asthma, nausea, vomiting, diarrhea, rhinitis, or anaphylaxis. Our study confirms the earlier reports of increased prevalence of food allergies in patients with LA. We also report increased prevalence of shellfish and fish allergy not previously reported. The nature of cross reacting epitopes or independent sensitization between latex and these foods is not clear.     

Diagnosis of latex hypersensitivity: comparison of different methods

A standardized diagnostic protocol for latex allergy is still lacking, although latex-related manifestations are a common health problem especially among health-care workers and patients with spina bifida. The present study was aimed to compare different in vivo (skin prick test, patch test, use test) and in vitro (specific IgE determination by CAP-Rast, basophil histamine release assay, immunoblot) methods to diagnose latex sensitization in 47 health care workers reporting latex-related manifestations. According to the established criteria, 20 subjects (42.5%) were considered as truly sensitized to latex, 18 with type I and 2 with type IV hypersensitivity. Skin prick test displayed the highest diagnostic efficiency, having higher sensitivity and specificity than specific IgE determination and use test. Patch test with rubber chemicals had a low sensitivity, but a good specificity. Basophil histamine release and immunoblot showed low sensitivity and specificity. A combination of clinical history and skin prick test should be used in order to diagnose latex allergy, except in those subjects reporting life-threatening reactions, in which in vitro specific IgE determination must be preferred. Patch testing with rubber chemicals should be reserved to selected cases. Basophil histamine release and immunoblotting can be performed for research purpose, but cannot be recommended for routine diagnostic use.     

Risk factors for latex sensitization among health care workers.

Health care workers, children with spina bifida and rubber industry workers show higher prevalence of latex sensitization compared to the general population, and they are considered at-risk groups. Our aim was to establish the prevalence of latex allergy among health care workers at the Clínica Universitaria of Navarra and to analyze potential risk factors, including personal and family history of atopy, sex, as well as factors leading to enhanced exposure to latex, such as being a nurse, belonging to surgical departments, having undergone previous surgery and the number of gloves employed per week. Health care workers (n = 1,150) (doctors, nurses, assistant nurses, laboratory technicians and practicing medical and nursing students) were evaluated using a questionnaire and skin prick test (SPT). Serum specific IgE was determined by CAP-FEIA (Pharmacia, Sweden) in those with positive SPT. The participation index was 26.17%: 301 volunteers answered the questionnaire and underwent SPT. Fifteen subjects presented positive SPT to latex. It was found that 5% of the health care workers from the Clínica Universitaria were sensitized to latex allergens. Thirteen were females and two males. Mean age was 38.4 (+/- 7.09) years. Nine were nurses, three assistant nurses, one nursing student and two medical doctors. Eight belonged to medical, five to surgical and two to laboratory departments. There were no significant differences among the subjects in the prevalence of latex sensitization. Fourteen reported symptoms related to latex, mostly pruritus, dryness and/or redness of the hands (n = 12) and rhinitis (n = 6). Only one subject reported no symptoms when using latex products. Eight were atopic; personal history of atopy was the only significant (odds ratio = 5.10, p < 0.01) risk factor for latex sensitization. It was concluded that atopic health care workers show a more increased risk of latex sensitization than those who are nonatopic.