Appraisal of latex glove proteins in the induction of sensitivity to multiple latex allergens.

Six Hevea brasiliensis latex protein allergens, Hevb 1, Hev b 2, Hev b 3, Hev b 4, and two variants of Hev b 7 (7b and 7c), were purified from Hevea latex, while a seventh protein, Hev b 5, was prepared in recombinant form. The presence of these proteins in glove extracts was indicated by their respective antibodies in the serum of rabbits immunized against the extracts. The relative propensities of IgE binding to the individual latex allergens were compared using sera from latex-allergic patients. IgE recognition of Hev b 4, Hev b 7b, Hev b 5 and Hev b 2 was most frequently encountered, with 75, 61, 31 and 28%, respectively, of the patient sera reacting. Sensitivity to multiple latex proteins was common, and out of the 31 seropositive patients, 23 (74%/ ) had IgE against at least two latex allergens, while 12 (39%) had IgE specific for at least three allergens. Statistical analysis of the data suggested that many patients might have acquired sensitivity to Hev b 2, Hev b 4 and Hev b 7b from a common source. (e.g., from latex products). On the other hand, sensitivity to Hev b 5 and to Hev b 7c were interrelated. It is plausible that sensitivity to these two proteins might have been acquired from sources other than latex products (e.g., from certain foods).     

Latex-vegetable syndrome due to custard apple and aubergine: new variations of the hevein symphony.

An increasing number of vegetables with crossreactions to latex are being described in patients with latex-vegetable syndrome. We present two of these vegetables, custard apple linked in two previous cases with latex sensitisation, and aubergine, that had not been described up to now in patients with latex sensitisation. The diagnosis of both cases was based on the clinical history, positive skin prick test (SPT) and specific IgE to the offending vegetables, as well as to positive SPT and specific IgE levels to latex and the major fruits involved in the latex-fruit syndrome (avocado, banana, and chestnut). Further, crude extracts from latex, custard apple and aubergine, as well as the purified allergens Hev b 6.02 and Prs a 1 were used in in vitro and in vivo assays: IgE immunodetection, histamine release (HRT) and basophil activation (BAT) tests and skin prick tests. In case 1, both purified Hev b 6.02 and Prs a 1 induced positive responses in skin prick tests, high levels of basophil activation and histamine release. Specific IgE immunodetection uncovered a reactive band of 45 kd in the crude custard apple extract, which was also recognized by anti-chitinase monospecific antibodies. The serum from patient 1 also detected Prs a 1 in immunodetection. Hev b 6.02 produced positive skin responses and showed high biological activity in HRT and BAT in the case of patient 2. However, Prs a 1 was reactive neither in SPT nor in IgE immunodetection. In fact, no band was detected using the serum of patient 2 in avocado or aubergine extracts. By contrast, Prs a 1 reached high values of basophil activation and over 10% of histamine release in case 2.     

Differential expression of allergens on the internal and external surfaces of latex surgical gloves

BackgroundDifferences in latex allergen sensitization profiles have been described between children undergoing repeated surgical interventions and health care workers. The purpose of this study was to determine whether such sensitization profiles are associated with differences in the expression of latex allergen between the internal and external surfaces of surgical gloves.MethodsExtracts were obtained from whole surgical gloves as well as from their external and internal surfaces. The extracts were centrifuged, filtered, concentrated, dialyzed and lyophilized. The protein profile of the extracts was analyzed using hydrophobic interaction chromatography (HIC) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Immunoblotting was performed using era from two patients with confirmed latex allergy. Latex recombinant allergen-specific IgE in these two patients was determined using a fluorescence enzyme immunoassay (FEIA) method. Latex allergen quantification was determined on both glove surfaces using an ELISA method.ResultsHIC and SDS-PAGE showed qualitative and quantitative differences in proteins between the internal and external glove surfaces, with the former being much richer in proteins. Immunoblotting of glove extracts using sera from two latex-allergic health workers showed differences between glove surface extracts. ELISA quantification of latex allergens demonstrated that the internal glove surface had high amounts of Hev b 5 and Hev b 6.02 whereas the external surface showed Hev b 1, Hev b 3, and Hev b 6.02.ConclusionsOur results reveal substantial differences in the composition of latex allergen profiles between the internal and external surfaces of surgical latex gloves, which may suggest a relationship between latex allergen localization and sensitization routes in different risk groups.     

Identification of latex UDP glucose pyrophosphorylase (Hev b UDPGP) as a novel cause of latex fruit allergy syndrome

Based on a recently published unusual ase of food allergy in a latex-allergic patients, the present study identifies Hev b UDPGP as a novel allergen in natural rubber latex able to cause latex-fruit allergy syndrome and as a novel, potential pan-allergen in vegetable foods.     

Characterization of a mouse model of allergy to a major occupational latex glove allergen Hev b 5

Allergen-specific immunotherapy is a clinically proven effective treatment for many allergic diseases, including asthma; however, it is not currently available for latex allergy because of the high risk of anaphylaxis. There is, therefore, a crucial need for an animal model of latex allergy in which to develop effective immunotherapy. Previous mouse models of latex allergy either did not characterize the allergic pulmonary immune response or used crude latex extracts, making it difficult to quantify the contribution of individual proteins and limiting their usefulness for developing specific immunotherapy. We immunized mice with recombinant Hev b 5, a defined major latex allergen, or latex glove protein extract, representing the range of occupationally encountered processed latex allergens. The immune response was compared with that seen in ovalbumin-immunized mice. Immunization with Hev b 5 or glove extract elicits hallmarks of allergic pulmonary Th2-type immune responses, comparable to those for ovalbumin, including (1) serum antigen-specific IgE, (2) an eosinophilic inflammatory infiltrate in the lung, (3) increased interleukin-5 in lung bronchoalveolar lavage fluid, and (4) mucus hypersecretion by epithelial cells in the lung airways. This mouse model will aid the development of potentially curative treatments for latex-sensitized individuals, including those with occupational asthma.     

Natural rubber latex allergy and asthma

Allergic responses to natural rubber latex (NRL) continue to be reported. In adults, the major exposure is in the occupational setting, especially in relation to NRL glove use by health care workers. Issues addressed over the past year include improving diagnostic methods for NRL allergy and characterization of NRL allergens relevant to various exposure groups and evaluating strategies for prevention and early detection of NRL allergy. Assessment of in vitro tests show good intertest correlation but lower sensitivity compared with skin test responses. NRL allergens have been further characterized as reported in the past year. Development of recombinant Hev b 3, a major NRL allergen relevant to children with spina bifida, enhances the likelihood for improved diagnostic reagents. Preliminary reports of primary preventive strategies suggest that avoidance of high-protein, powdered gloves in health care facilities can be cost-effective and is associated with a decline in sensitized workers.     

Hev b 6.02 Is the Most Important Allergen in Health Care Workers Sensitized Occupationally by Natural Rubber Latex Gloves

BackgroundNatural rubber latex (NRL) allergy is a common occupational disease in health care workers (HCW). However, few reports have compared the major allergen of HCWs to those in gloves that are routinely used in the hospital. The aim of this study was to evaluate the major NRL allergens in gloves used by HCWs.MethodsWe studied 20 HCWs who were suspected to have latex allergy (LA). We performed a skin prick test (SPT) using NRL allergens. Serological testing was performed using the ImmunoCAP?. The total amount of protein and the antigenic protein concentrations extracted from NRL gloves were measured. Four different types of FITkit? were used to measure the concentrations of Hev b 1, 3, 5, and 6.02 in the gloves.ResultsA SPT using NRL extract identified 14 cases with positive reactions. The sensitivity and specificity of the SPT scores to the NRL glove extract were 100%. The sensitivity of latex specific IgE was 100% but the specificity was 14.2%. The sensitivity and specificity of rHev b 6.02 specific IgE were 100% in the LA group. The total amounts of protein from the medical gloves for surgery and examination were 265 μg/g and 95 μg/g, respectively. The antigenic protein concentrations in the gloves were 24.9 μg/g and 1.0 μg/g, respectively. The total amounts of the specific four allergens in the NRL gloves were 2.18 μg/g and 0.45 μg/g, respectively.ConclusionsWe concluded that the main allergen of HCWs who have been sensitized occupationally by NRL gloves was Hev b 6.02.     

Sublingual rush immunotherapy with latex extract in children

Latex allergy prevalence has increased notably in the last two decades. Latex ubiquity and its cross-reactivity with fruits make complete avoidance difficult to attain and studies have questioned long-term avoidance efficacy. Subcutaneous and sublingual routes of specific immunotherapy (SIT) to latex have been tested in double blind placebo controlled studies, with significant improvement in patients' tolerance to latex. We present our experience with a sublingual desensitization protocol in three latex allergic children. The build-up phase consisted of rush, with daily admission for 4 consecutive days, followed by a maintenance period at home. Only local reactions, with good response to antihistamines were observed during rush and no reactions have been reported with maintenance dose during 6, 5 and 2 months, respectively. The first patient has accomplished 6 months maintenance treatment. Allergological re-evaluation has shown a decrease in skin reactivity and serum specific IgEs to latex and cross-reactive fruits. Comparison of the results of specific IgEs measurement to a panel of latex recombinant allergens before rush and 6 months later clearly showed a decrease in Hev b 5 and Hev b 6.01, with no other detectable new sensitizations. Immunoblot was also performed before rush and 6 months later and shows a decrease in sensitization without appearance of new bands. Future enlargement of our series and prospective follow-up will help to clarify the real clinical efficacy of sublingual SIT. As this is a safe and easy to use protocol, it seems to be specially appropriate for children.     

Quoi de neuf en allergologie pédiatrique en 2006-2007 ? Partie 3: Allergie cutanée, alimentaire, médicamenteuse et aux insectes (une revue de la littérature internationale d’octobre 2005 à septembre 2007)

Most sensitizations in children with atopic dermatitis are non pathogenic. Thus, responses in prick-tests, specific IgE determinations and patch-tests should be carefully evaluated based on the clinical history of the children or responses in challenge tests. Moreover, although atopy patch-tests are highly specific, they have a low sensitivity. Food eviction is indicated in a few children only, since they may be responsible for anaphylactic reactions induced by accidental ingestion of the food or oral challenge tests. The predictive value of serum specific IgE to foods depends on the food investigated, the age of the children, their allergic disease (atopic dermatitis, urticaria/angioedema, anaphylaxis) and, may be, on their ethnical origin. The prevention of food-induced severe reactions is based on eviction. However, several studies suggest that oral desensitization to foods may be efficient. Most frequent reactions in children hypersensitive to antalgics, antipyretics and nonsteroidal antiinflammatory drugs are oedema (facial oedema especially) and urticaria. Usually, the severity of the reactions increases from one treatment to another one and with the dose of drug administered to the children. Diagnosis is based on a convincing clinical history or on challenge tests. Skin tests with vaccines should be performed according to a standardized procedure because they may give false positive responses. Most latex sensitizations detected by skin prick-tests and, especially, specific IgE determinations are non pathogenic. The prevention of reactions to latex is based on eviction. However, preliminary results suggest that sublingual desensitization with a latex extract is efficient and well-tolerated.     

Prick-prick with fresh foods in patients with latex allergy.

The quick spread of AIDS and other contagious infectious diseases has resulted in what was first voluntary, and subsequently recommended and compulsory, use of protection from contact with blood or bodily fluids. This protection has been especially widespread in the healthcare field. In the in vivo diagnosis of food allergy, it has been proven that the skin prick-prick test is sometimes more sensitive than skin prick test with commercial extracts. The aim of our study was to prove that handling fresh foods prepared for the prick-prick test with latex gloves can tamper with the results in patients with latex allergy. Statistically significant differences were found (p <0.001) between patients and controls in the prick-prick tests against the different foods after handling with latex gloves. No significant differences were found in controls for each prick-prick test for food with or without manipulation with latex gloves. Significant differences were found in the group of patients when performing prick-prick with the different foods before and after manipulation with latex gloves. We also observed that there were significant differences in prick-prick test between patients with latex sensitization and nonsensitized controls, and that the results of prick-prick test varied for each patient depending on whether or not foods had been handled with latex gloves.     

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.     

Latex versus lodinated contrast media anaphylaxis in the cardiac cath lab

A 65-year-old man had bypass surgery 10 years previously with pulmonary artery catheter monitoring. Shortness of breath and mitral regurgitation necessitated repeat left and right heart catheterization using a pulmonary artery catheter. Before any iodinated contrast media exposure, the pulmonary artery catheter was inserted and within 2 min the patient developed anaphylaxis associated ventricular fibrillation. It was discovered that the pulmonary artery catheter used in the cath lab had a latex balloon and that the patient had been exposed to latex 10 years ago. Latex induced anaphylaxis is rarely considered in the differential diagnosis of patients with hypersensitivity reactions in the cath lab, intensive care unit, and operating room. The principal reason for failure to recognize the latex balloon as a potential allergen is that most health professionals are not aware that almost all pulmonary artery catheters contain a latex balloon. The risk of an allergic response to latex is 0.8% for the general population. Others at high risk include those who have had multiple surgical procedures and interventions with repeated latex exposure. Five to 10% of all U.S. health professionals and those performing household duties wearing latex gloves have an allergic response to latex. Latex hypersensitivity is an IgE dependent reaction, while iodinating contrast medium reaction is an IgE independent reaction. If latex hypersensitivity is suggested by pre-procedural history or if the patient falls into a high-risk group, pre-procedural skin testing and/or latex IgE radioallergosorbent (RAST) should be performed. A latex-free pulmonary artery catheter (Zeon Medical, White Plains, NY) has been evaluated and found to have favorable performance characteristics from the femoral, jugular, and subclavian approach and is an economic equivalent to the conventional pulmonary artery catheters which contain latex. © 1995 Wiley-Liss, Inc.     

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.     

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.     

Summary of appropriate measures to prevent natural rubber latex allergy

This paper presents a short overview of the diagnostics and background of type I allergy to natural rubber latex proteins and makes recommendations for preventing corresponding allergic diseases in the future. These recommendations and prevention strategies are based on the current knowledge of latex allergy presented in the literature and are addressed to legislative bodies; manufacturers; directors of hospitals; those working at nursing facilities and physicians' and dentists' practices; as well as to other health service employees. Primary prevention is the focus but advice is also given on secondary prevention. The major preventive aim is the elimination of causative protein allergens in all latex devices and thus, the minimization of latex-related health problems.     

Latex protein: a hidden "food" allergen?

Avoidance of latex allergens is the primary method to prevent adverse reactions. Natural rubber latex is found in many different products in both the health care industry and in modern society, and consequently results in unexpected exposures of sensitized individuals. The use of latex gloves by food handlers provides one potential route for inadvertent exposure to latex allergens. In this study we have used two immunological methods to determine whether latex proteins are transferred to foods following contact with latex gloves. Direct transfer of latex protein to cheese was visualized using a modified immunoblot method. Sliced cheese was touched with a gloved finger. A nitrocellulose membrane was applied to lift the potential fingerprints and a rabbit anti-latex antiserum was used to visualize the transfer of any latex finger-prints. After handling lettuce with gloves, transferred protein was recovered by extracting the lettuce and quantified using an inhibition ELISA for latex proteins. Fingerprints of latex protein were readily detectable on cheese after contact with powdered latex gloves, but not with vinyl gloves. Furthermore, powdered latex glove use resulted in measurable amounts of latex protein on lettuce with an exposure-dependent increase in the latex protein levels. Lettuce alone or lettuce handled with vinyl gloves was negative for latex protein. The use of latex gloves by food handlers is the source of an indirect food additive in the form of latex proteins. It is recommended that food handlers avoid the use of latex gloves to eliminate inadvertent exposure of latex-sensitive individuals.     

Treatment perspectives: immunotherapy with latex

Latex allergy currently constitutes a serious problem because of the severity of its symptoms and the at-risk groups it affects. Since complete avoidance of this substance is practically impossible, in the last few years intense efforts have been made to standardize a latex extract with the aim not only of improving clinical diagnosis but also of being able to offer other therapeutic alternatives, such as specific immunotherapy.Since 1998, reports of immunotherapy with oral (three patients) subcutaneous (one patient) and sublingual latex desensitization (one patient) have been published. In all cases, clinical improvement was evident. In 2000, Laynadier published the first pilot study, a phase IIB multicenter, randomized, double-blind, placebo-controlled trial that evaluated the efficacy and safety of specific immunotherapy with latex in patients with occupational allergy. Twenty health care workers without obvious latex exposure and with latex allergy-induced symptoms of rhinitis and/or asthma were included. Treatment started with a 2-day course of rush immunotherapy in hospital and maintenance therapy was continued for 1 year. Efficacy was assessed by symptom and medication scores and by variation in the conjunctival reactivity threshold. The safety of the extract was also evaluated. In the overall analysis of symptom score, the treated group showed a marked improvement and the medication score was significantly lower in patients in the active treatment group than in the placebo group. Concerning safety, almost half the patients receiving active treatment showed local reactions starting with the first injection and four of the nine patients in this group suffered moderate-to-severe systemic reactions. In view of this first clinical trial, it can be concluded that this treatment is effective but that its tolerance is low.A second clinical trial with the same characteristics and extract is currently underway. Its aim is to validate the previous protocol, confirm the efficacy of specific immunotherapy with latex, improve its safety and, if possible, determine the optimal dose.J. Sastre et al. have recently (Formigal 2002) presented the results of the first double-blind study with latex immunotherapy using an extract standardized by the ALK-Abelló-Espa?a group. The authors included 24 patients with latex sensitization and symptoms of occupational allergy. To diagnose respiratory allergy, an inhalation challenge was performed in a closed 7-m2 chamber and, in case of contact urticaria, glove-wearing and rubbing tests were performed, using a vinyl glove as negative control. Treatment consisted of a first phase of incremental doses for 14 weeks, with 18 injections, followed by maintenance doses for 6 months. Sixteen patients received active treatment and 8 received placebo. Of the 578 doses administered, adverse effects were observed in 41 (7.1 %). There were 21 immediate systemic reactions (5.7 % of the doses) and 10 delayed systemic reactions (2.6 % of the doses). Adverse effects were more frequent in patients with underlying respiratory disease (p < 0.05). After 6 months' treatment, a clear improvement in the cutaneous response index was found in the active treatment group and in the rubbing and glove-wearing tests. The authors conclude that the immunotherapy tested was a high-risk treatment and that the greatest clinical improvement was found in cutaneous symptoms.In conclusion, although effective, latex immunotherapy is currently a high-risk treatment.     

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.     

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.     

In-use barrier integrity of gloves: latex and nitrile superior to vinyl.

BACKGROUND: Although gloves manufactured with different materials have comparable barrier properties when removed directly from the box and tested, their actual on-the-job barrier performance may be extremely different. Although effective in static, pre-use conditions, barrier properties may be compromised once challenged by the rigorous hand and finger movements associated with many health care procedures. Gloves are meant to act as barriers, protecting persons by reducing the risk of exposure to bloodborne pathogens. Ineffective barriers or barriers that are easily breached during risk-associated procedures have the potential to place health care professionals at risk. Multiple studies attesting to the barrier attributes of vinyl and latex gloves during varied controlled clinical situations are available. Studies are available that address the permeation characteristics of nitrile, but no studies document the effectiveness of nitrile as a barrier to bloodborne pathogens or compare the barrier effectiveness of nitrile to gloves made of other materials during simulated use or clinical situations. OBJECTIVE: This study was undertaken to compare the barrier integrity of latex, vinyl, and nitrile gloves during controlled, simulated clinical use conditions that were specifically designed to mimic patient care activities. This study compares the performance of gloves made of natural rubber latex, long considered the gold standard; polyvinyl chloride (vinyl), a synthetic copolymer; and nitrile (acrylonitrile butadiene), a recently available synthetic for use in the health care environment. METHODS: A total of 2000 gloves (800 latex gloves, 800 vinyl gloves, and 400 nitrile gloves) were evaluated for baseline determinations in unused gloves and for failure rates after specific simulated use conditions. Potential bias was avoided through strict control of all actions and manipulations. Gloves were graded on a pass or fail system for leaks as defined by American Society for Testing and Materials D5151, Standard Test Method for Detection of Holes in Medical Gloves. To more fully characterize the gloves evaluated, individual products were also tested for physical dimensions (finger and palm thickness), powder levels, total protein (Modified Lowry), and antigenic protein (Latex ELISA [enzyme-linked immunosorbent assay] for Antigenic Proteins). RESULTS: With the exception of one vinyl glove brand with a 12% failure rate, no significant differences in failure rates were detected among the 3 types of gloves when tested directly out of the box with no manipulation. However, after manipulation intended to simulate in-use conditions, vinyl gloves failed 12% to 61% of the time. Latex and nitrile performed significantly better, with failure rates of only 0% to 4% and 1% to 3%, respectively. All latex gloves, with one exception, tested at less than 50 microg/g of total water extractable protein. The antigenic protein levels, with one exception, tested from less than 0.2 microg/g to 5.5 microg/g. The one latex product that fell outside these values had 154 microg/g of total protein and 105.7 microg/g of antigenic protein. CONCLUSIONS: This study indicates that the latex and nitrile gloves evaluated were comparable in terms of barrier performance characteristics both unused and during manipulations mimicking patient care procedures. Whereas stretch vinyl exhibited lower failure rates than standard vinyl, the higher in-use leakage rates associated with all vinyl gloves tested indicate decreased durability and, potentially, compromised barrier protection when this synthetic is used. Careful consideration to the degree of barrier effectiveness should be given before glove selection when the potential exposure to bloodborne pathogens or biohazard risks is a concern.