Type I latex allergy in health care workers with latex-induced contact urticaria syndrome: a follow-up study

Contact dermatitis

Contact dermatitis (CD) is among the most common inflammatory dermatological conditions and includes allergic CD, photoallergic CD, irritant CD, photoirritant CD (also called phototoxic CD) and protein CD. Occupational CD can be of any type and is the most prevalent occupational skin disease. Each CD type is characterized by different immunological mechanisms and/or requisite exposures. Clinical manifestations of CD vary widely and multiple subtypes may occur simultaneously. The diagnosis relies on clinical presentation, thorough exposure assessment and evaluation with techniques such as patch testing and skin-prick testing. Management is based on patient education, avoidance strategies of specific substances, and topical treatments; in severe or recalcitrant cases, which can negatively affect the quality of life of patients, systemic medications may be needed.

Occupational management of type I latex allergy

BACKGROUND

Although the incidence of type 1 latex allergy has decreased in recent years with the introduction of powder-free low-protein (PFLP) latex gloves, type 1 latex allergy is still commonly found among workers who use natural rubber latex (NRL) gloves at work.

AIMS

To elucidate the optimal management of workers with type 1 latex allergy whose work necessitates the use of NRL gloves in the workplace.

METHODS

A sensitive electronic search of relevant bibliographic databases was performed with related search terms for articles from 1 January 1990 to 1 September 2010. Relevant abstracts were reviewed, and studies that furnished data on the management of type 1 latex allergy in the workplace were extracted. Articles for inclusion in the review were appraised using the Scottish Intercollegiate Guideline Network methodology.

RESULTS

A total of 7041 abstracts were retrieved; 12 articles met the inclusion criteria for the review. We found moderately strong and consistent evidence that avoidance of NRL in the workplace reduces both symptoms and markers of sensitization in latex-allergic individuals. There is limited evidence that latex-allergic workers can continue to use PFLP gloves with no worsening of symptoms, provided that their co-workers also use PFLP latex or non-latex gloves.

CONCLUSIONS

Individuals with type 1 latex allergy whose work necessitates them wearing latex gloves may continue in their job provided that adjustments are made to ensure that they are not exposed to powdered latex gloves.

The safety of a novel sublingual rush induction phase for latex desensitization

OBJECTIVES

In latex allergic individuals the avoidance of all exposure to natural rubber latex products is recommended. Sublingual immunotherapy against latex has recently been proposed. The aim of the study is to evaluate the tolerability of sublingual immunotherapy with latex extract, by a double-blind, placebo-controlled study, according to a three-day build-up phase rush protocol in a population of patients with latex-induced contact urticaria without a professional exposure to latex.

METHODS

Twenty-one patients with latex-induced urticaria were randomized to receive sublingual immunotherapy (SLIT) with latex extract or placebo. Rush (3-day) induction protocol of latex sublingual immunotherapy was performed with increasing doses of ALK-Abelló latex extract at three concentrations of latex proteins (5, 50 and 500 microgmL(-1)). Any side-effects that might be related to immunotherapy, the corresponding dose and treatment were registered.

RESULTS

Among the 21 patients, 12 were treated with latex sublingual immunotherapy (9 women and 3 men) and 9 with placebo (8 women and one man). All patients ended the rush protocol. Four patients (19.0%) [one in the SLIT group (8.3%) and three in the placebo group (33.3%)] developed adverse reactions. One SLIT patient reported mouth itching and burning of the tongue. In the placebo group, one patient presented gastrointestinal complaints while two patients reported unspecific symptoms. All these side-effects regressed spontaneously. No statistically significant differences were found between the proportions of adverse events in the two examined groups.

CONCLUSION

This study supports the safety of SLIT against latex conducted in adult patients with latex-induced contact urticaria according to a 3-day build-up phase rush protocol. The proposed 3-day induction phase for latex sublingual immunotherapy should be conducted under medical supervision, although in patients with only latex-induced contact urticaria the registered adverse reactions were so slight that it could be argued that patients could start safely our tested rush protocol at home.

Percutaneous reactivity to natural rubber latex proteins persists in health-care workers following avoidance of natural rubber latex

BACKGROUND

Long-term avoidance of natural rubber latex [Hevea brasiliensis (Hev b)] is currently recommended for health-care workers (HCWs) with established natural rubber latex (NRL) allergy. Percutaneous sensitivity to eight Hev b NRL allergens was evaluated in HCWs in 2000. To date, no studies have evaluated the longitudinal effects of NRL avoidance on percutaneous sensitivity to NRL allergens.

OBJECTIVE

The aims of this study were to evaluate changes in percutaneous reactivity to non-ammoniated latex (NAL) and NRL allergens in HCWs 5 years after a recommendation to avoid NRL and to evaluate factors that predict the persistence of in vivo sensitivity to NAL and NRL allergens.

METHODS

Skin prick testing was performed with NAL, seven NRL allergens (Hev b 1, 2, 3, 4, 6.01, 7.01, and 13), and recombinant Hev b 5 (rHev b 5) in 34 HCWs who were initially evaluated in 2000 for occupationally related NRL allergy. Serial 10-fold dilutions of NAL and NRL allergens were employed in skin testing. Sera from the HCWs were assayed for latex and enhanced latex (rHev b 5-enriched allergosorbent)-specific IgE antibodies using the ImmunoCAP assay.

RESULTS

The prevalence of work-related symptoms significantly decreased between 2000 and 2005 with avoidance of NRL (P<0.05). A >/=100-fold reduction in percutaneous sensitivity to Hev b 2 and Hev b 7 was less likely in those with prior history of systemic reactions to NRL (P=0.0053), reported history of reaction to cross-reactive foods (P=0.014), continued local reactions to NRL gloves (P<0.0001), or high NRL glove exposure since the initial study (P=0.0075). The diagnostic sensitivity and specificity of the latex-specific IgE serology was 54% and 87.5%, respectively, in comparison with NAL skin tests. The addition of rHev b 5 to the ImmunoCAP (enhanced latex) allergosorbent altered the diagnostic sensitivity and specificity of the ImmunoCAP to 77% and 75%, respectively.

CONCLUSION

While symptoms may resolve quickly with NRL avoidance therapy, detectable IgE indicating continued sensitization remains beyond 5 years, and thus continued avoidance of NRL should be recommended.

Double-blind, placebo-controlled study of sublingual immunotherapy in patients with latex-induced urticaria: a 12-month study

BACKGROUND

Natural rubber latex (NRL) allergy is a worldwide problem. Although prevention is sufficient to reduce sensitization, prolonged avoidance is needed to prevent resensitization or adverse reactions on re-exposure.

OBJECTIVES

This double-blind, placebo-controlled study was conducted to determine the efficacy of sublingual immunotherapy (SLIT) with latex.

METHODS

Forty patients with NRL allergy were enrolled. At diagnosis, 30 presented urticaria and 10 asthma. Patients were evaluated on their clinical history and an allergological assessment: skin prick test with latex extract, serum-specific IgE and provocation tests. Patients were subdivided by complaint (asthma or urticaria), and randomized to receive SLIT with latex extract (ALK-Abelló, Lainate, Milan, Italy) or placebo.

RESULTS

The evaluable population consisted of 35 patients, 18 treated with SLIT and 17 with placebo. The results show that 12 months of SLIT improved the symptoms score and reduced the medication score in all subjects. The subjective evaluation was corroborated by improved bronchial and glove provocation test results. The latex-specific IgE levels increased slightly in the SLIT group, and skin sensitization was reduced at the end of the trial in all the patients treated with SLIT. The immunotherapy was not complicated by any severe adverse reactions.

CONCLUSIONS

This is the first double-blind, placebo-controlled evaluation of the efficacy of SLIT with latex extract conducted in adult patients allergic to NRL. SLIT with latex can be proposed for subjects with latex allergy, especially those for whom complete avoidance of latex exposure may be very difficult or even impossible. More studies are needed to evaluate the efficacy of SLIT in the treatment of subjects with latex allergy who are sensitized to inhalant allergens.

Occupational allergy to latex among loom tuners in a textile factory

BACKGROUND

Occupational allergy to latex is generally reported from occupational groups such as health care workers; however, few reports derive from other occupational settings.

METHODS

Two male subjects working as loom tuners in a textile manufacturing plant developed severe allergic reactions during the cutting and weaving of elastic bands, initially not suspected to contain latex constituents. Clinical evaluation and lung function tests were supplemented by skin prick testing, specific IgE evaluation and basophil activation assays with extracted elastic bands.

RESULTS

Both workers presented with rhinitis, episodes of tight chest and itchy eyes. Initial spirometry was normal with no significant reversibility; however, a histamine challenge test was positive in one worker. Skin prick testing to a battery of common inhalant allergens was negative; however, raised IgE levels were detected to latex using ImmunoCAP. On further testing, the specific IgE response was directed mainly to the major latex allergens rHev b 5, rHev b 6.01, rHev b 6.02 and nHev b 13. Basophils of the two workers, but not the unaffected control subjects, were strongly activated by extracts of the elastic and the cutting dust material.

CONCLUSIONS

Workers are at high risk of becoming sensitised to latex allergens when exposed to excessive dust produced by loom tuning machines. Latex sensitisation should therefore be considered in workers developing unexplained work-related allergic reactions (including asthma) associated with unlabelled materials in the textile industry.

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.

[Sensitization to powdered latex gloves: prevalence in hospital employees]

INTRODUCTION

The prevalence of latex allergies in industrial countries has skyrocketed since the 1980s. Between 2.6 and 22% of hospital workers are diagnosed with latex allergy, which has been recognized as an occupational hazard in France since 1997.

AIM

To assess the prevalence of latex allergy among Montpellier University Hospital Center staff.

METHODS

From 1999 to 2002, we interviewed and conducted skin-prick tests on 537 hospital staff members from different departments and with different degrees of exposure to airborne latex allergens.

RESULTS

Symptoms while using natural-rubber latex gloves (most often contact dermatitis) were reported by 88 (16.4%) staff members. Overall work-related allergic symptoms included rhinitis, reported by 65 (12.1%), contact urticaria by 28 (5.2%), and bronchial symptoms by 16 (1.1%). In all, sensitization to latex was identified in 7.1% of our staff, and this percentage was higher (11.3%) in units where latex gloves were used more often. Sensitization was associated with high latex exposure and atopy.

CONCLUSION

This high rate of latex sensitization and the risk factors are similar to those already published. Based on this study, we have eliminated powdered latex gloves, as have many other hospitals.

Toxicological and immunological aspects of occupational latex allergy

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