Latex hypersensitivity: relationship with positive prick test and patch test responses among hairdressers

Use of protective gloves by hairdressers: A review of efficacy and potential adverse effects

Occupational hand eczema is common among hairdressers, and protective gloves are important in limiting exposure to irritants and allergens. Various glove types may differ in their protective ability, and their use may lead to hand eczema due to skin irritancy and allergy. MEDLINE was searched for studies investigating permeation of gloves to irritants and allergens used in the hairdressing trade, as well as adverse effects of glove use affecting hairdressers. Forty-four studies were identified; nine reported on permeation. Of those, two in vitro studies found nitrile rubber (NR) gloves to give the best protection when handling hair dyes. Polyethylene (PE) gloves had the lowest reported break-through time. The prevalence of sensitization to rubber materials in European hairdressers was as follows: thiuram mix, median 2.5% (range 0%-8.2%), weighted average 3.0% (95% confidence interval [CI] 3.0%-3.1%); mercapto mix, median 0.4% (range 0%-3.3%), weighted average 0.5% (95% CI 0.47%-0.50%), mercaptobenzothiazole, median 0.6% (range 0%-6.6%), weighted average 0.7% (95% CI 0.6%-0.7%), NRL-type I allergy, median 1.3% (range 1%-16.4%), weighted average 4.0% (95% CI 3.6%-4.5%). In conclusion, NR gloves provide the best skin protection for hairdressers, although natural rubber latex (NRL) and polyvinylchloride (PVC) gloves may be sufficient in most cases. PE gloves are not recommended. Synthetic rubber gloves with low or no levels of accelerators are preferred.

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.

Self-reported hand symptoms: a role in monitoring health care workers for latex sensitization?

BACKGROUND

The use of powdered natural rubber latex (NRL) gloves increased greatly in the 1980s because of concerns about transmission of blood-borne infections and the subsequent implementation of universal precautions. The most common clinical reactions to glove use are irritant and T-cell-mediated contact dermatitis. However, IgE-mediated immediate reactions to latex have become a serious concern for health care workers (HCWs). The diagnosis of latex allergy requires a comprehensive medical history and diagnostic tests. The skin prick test is the preferred diagnostic method, although it can be time-consuming.

OBJECTIVE

To determine the role of hand symptoms reported on questionnaires in monitoring HCWs for latex sensitization.

METHODS

Questionnaires were completed by 804 HCWs at 2 hospitals. Using a positive skin prick test (SPT) result as a criterion standard of latex sensitization, the diagnostic performance of hand symptoms was evaluated.

RESULTS

Increasing latex glove use was strongly related to increasing reports of hand symptoms. Hand symptoms were highly associated with glove-related respiratory and systemic symptoms. A positive SPT result was seen in 5% of HCWs and increased with the number of hand symptoms: 0 (1.6%), 1 to 2 (3.4%), and 3 to 7 (19.0%). Participants reporting more than 2 hand symptoms were 11 times more likely to have positive SPT results compared with those with 2 or fewer hand symptoms.

CONCLUSION

Hand symptoms are closely associated with latex sensitization. Questionnaires should be useful in health monitoring for HCWs who use latex gloves.

Review on the validity of self-report to assess work-related diseases

PURPOSE

Self-report is an efficient and accepted means of assessing population characteristics, risk factors, and diseases. Little is known on the validity of self-reported work-related illness as an indicator of the presence of a work-related disease. This study reviews the evidence on (1) the validity of workers' self-reported illness and (2) on the validity of workers' self-assessed work relatedness of an illness.

METHODS

A systematic literature search was conducted in four databases (Medline, Embase, PsycINFO and OSH-Update). Two reviewers independently performed the article selection and data extraction. The methodological quality of the studies was evaluated, levels of agreement and predictive values were rated against predefined criteria, and sources of heterogeneity were explored.

RESULTS

In 32 studies, workers' self-reports of health conditions were compared with the "reference standard" of expert opinion. We found that agreement was mainly low to moderate. Self-assessed work relatedness of a health condition was examined in only four studies, showing low-to-moderate agreement with expert assessment. The health condition, type of questionnaire, and the case definitions for both self-report and reference standards influence the results of validation studies.

CONCLUSIONS

Workers' self-reported illness may provide valuable information on the presence of disease, although the generalizability of the findings is limited primarily to musculoskeletal and skin disorders. For case finding in a population at risk, e.g., an active workers' health surveillance program, a sensitive symptom questionnaire with a follow-up by a medical examination may be the best choice. Evidence on the validity of self-assessed work relatedness of a health condition is scarce. Adding well-developed questions to a specific medical diagnosis exploring the relationship between symptoms and work may be a good strategy.

Latex allergy: a model for therapy

Allergy to natural rubber latex products emerged as an important clinical condition following an increase in the use of latex gloves for barrier protection in the early 1980s. In addition to latex glove users, other high-risk groups with different latex exposure include spina bifida patients and others with multiple surgical procedures. Subjects with fruit and vegetable allergy are also at risk due to cross-reactive allergens. Following the significant advances in the identification and characterization of common aeroallergens, latex allergy was well placed to become an excellent model of therapy. Awareness of latex allergy and modes of sensitization enabled epidemiological studies to inform allergen avoidance initiatives, substantially reducing inadvertent exposure in major hospitals in Western countries. Spina bifida is often identified in utero or soon after birth, allowing vigorous latex allergen avoidance with enhanced efficacy of primary prevention. However, changing demographics of latex allergy and technological revolution in countries such as China and India are predicted to unleash a second wave of latex allergy reemphasizing the incentive for improved manufacturing procedures for latex products. The desirable high tensile strength and elasticity of natural rubber latex have made the commercial identification of good alternatives very difficult but this would also be attractive for primary prevention. In addition, an effective specific immunotherapy regimen would be valuable for selected high-risk atopic individuals. Current subcutaneous and sublingual immunotherapy schedules have been tested for treatment of latex allergy with evidence of efficacy but the risks of adverse events are high. For such potent allergens as latex, hypoallergenic but T cell-reactive preparations are required for clinical use. Identification of allergenic components of latex products, with generation of monoclonal antibodies and recombinant allergens, allowed sequence determination and mapping of T cell and B cell epitopes. Together, these reagents and data facilitated improved diagnostics and investigation of novel-specific therapeutics. Potential hypoallergenic latex preparations identified include modified non-IgE-reactive allergen molecules and short T cell epitope peptides. The co-administration of adjunct therapies such as anti-IgE or corticosteroids and of appropriate adjuvants for induction of regulatory T cell response offers promise for clinically effective, safe latex-specific vaccines.

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.

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.

Latex allergy and skin

PURPOSE OF REVIEW

In this review we address the prevalence and outcome of latex allergy in health care workers (HCWs). Recent findings in natural rubber latex (NRL) allergens and trials of specific immunotherapy (SIT) are also of interest.

RECENT FINDINGS

A study involving skin prick test (SPT) screening in HCWs in Russia and adjacent countries found a prevalence of latex allergy of 1.9%. Questionnaire studies performed in Wales and in the USA identified prevalence rates of about 0.6%. An intervention undertaken at the Mayo Clinic, in which only gloves with low or undetectable allergen levels were allowed, reduced markedly the incidence of NRL allergy. Two studies, one from Finland and another from Ohio, showed that outcomes in latex-allergic HCWs are generally good. A study involving SPT screening showed that 6% of construction workers had latex allergy. A questionnaire study among allergists practicing in the USA showed that 62% performed latex SPT and 6% reported anaphylaxis, which mostly occurred while using a homemade SPT solution. Hev b 2, Hev b 5, Hev b 6.01 and Hev b 13 produced positive SPT reactions in over 60% of latex-allergic individuals. Topical application of NRL in a murine model of protein contact dermatitis caused a striking increase in prohevein-specific (Hev b 6.01) immunoglobulin E levels, together with a T-helper-2 type dermatitis. A placebo-controlled SIT trial with NRL extract alleviated cutaneous symptoms but caused some systemic reactions in latex-allergic patients.

SUMMARY

Low prevalence rates suggest that the peak of the latex allergy epidemic has already passed in HCWs. Hospital-wide interventions requiring use of low-allergen gloves reduce sensitization and changing gloves to nonlatex ones, or even using low-allergen latex gloves, in the affected individuals appears to confer adequate secondary prevention. In the USA there is an urgent need for standardized latex SPT reagent. Hev b 5 and Hev b 6.01 are major in vivo NRL allergens. Findings in mice suggest that NRL proteins eluting from latex gloves may also cause hand eczema in humans. SIT with NRL extract must still be considered an experimental treatment.

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

BACKGROUND

Latex allergy is an important occupational health issue among health care workers (HCWs). Secondary prevention in sensitized/allergic individuals involves avoiding exposure to NRL products.

AIMS OF THE STUDY

The aim of this follow-up study is to determine the long-term health consequences in HCWs with type I latex allergy with latex-related contact urticaria syndrome, of providing appropriate information and practical avoidance education.

METHODS

Seventeen HCWs with latex-induced contact urticaria syndrome, as ascertained by the glove use test, were investigated. Initial and follow-up visits included: a detailed questionnaire, skin prick test (SPT) with glove eluates and with commercial latex extract, SPT with common inhalant and food extracts, serum specific immunoglobulin (Ig)E to latex and some foods and the glove use test.

RESULTS

On re-examination, 11 (64.7%) subjects showed positive SPTs to extemporaneous extract and 10 (58.8%) patients showed a positive SPT to commercial extract. Of the nine patients with detectable levels of serum latex specific IgE at first evaluation, four (44.4%) became negative and four were assigned to at least one class lower. Only one (11.1%) employee had higher radioallergosorbent test values than those at the latex allergy diagnosis. At follow-up, the 17 individuals had positive latex challenge results, although the duration of exposure causing a reaction increased.

CONCLUSION

Our study shows that preventive measures are sufficient to induce a reduction of sensitization. Continued avoidance is needed to prevent re-sensitization or adverse reactions on re-exposure.