Decreasing incidence of occupational contact urticaria caused by natural rubber latex allergy in German health care workers

Contact urticaria and protein contact dermatitis in the Finnish Register of Occupational Diseases in a period of 12 years

BACKGROUND

Although occupational contact urticaria (CU) and protein contact dermatitis (PCD) are considered frequent among workers with exposure to proteinaceous materials, data on occupations at risk and the main causes of these occupational skin diseases are relatively limited.

OBJECTIVES

To report the causative agents and risk occupations for CU and PCD in the Finnish Register of Occupational Diseases (FROD).

METHODS

We retrieved from the FROD all recognized cases of CU/PCD in the years 2005-2016.

RESULTS

With 570 cases, CU and PCD constituted 11% of all recognized cases of occupational skin diseases in the study period. Occupations with the highest incidence of CU/PCD included bakers, chefs and cooks, farmers and farm workers, veterinarians, gardeners, and hairdressers. The most common causative agents were cow dander and flour and grain, followed by natural rubber latex (NRL) and other food. In food-related occupations, wheat and other flours were by far the most common cause of CU/PCD, with 76 cases, whereas fish and other animal-derived food caused 33 and other plant-derived food caused 23 cases.

CONCLUSIONS

Apart from the Finnish peculiarity of cow dander allergy, a striking finding was a large share of CU/PCD caused by flours in food handlers as compared to other food.

[Prevention of hand eczema]

Apart from endogenous factors, hand eczema is often caused by irritant or allergic contact dermatitis related to occupational or non-occupational exposure to skin hazards. This enables several complementary approaches on the level of primary, secondary and tertiary prevention. A high priority is set on identification and subsequent reduction or elimination of causative exposures. Important preventive approaches include legal regulations, technical and organizational measures as well as correct use of adequate personal protective equipment (e.g. protective gloves). Interventions based on health education are conducted to improve individual protective behaviour. Even though evidence-based proof of effectiveness is limited, preventive measures are considered of particular importance for avoidance of occupational hand eczema and its adverse sequelae. Therefore, a complex, step-wise approach to occupational skin diseases has been established in Germany. In recent years, the positive impact of secondary and tertiary preventive measures of this approach has been demonstrated.

Contact urticaria: Frequency, elicitors and cofactors in three cohorts (Information Network of Departments of Dermatology; Network of Anaphylaxis; and Department of Dermatology, University Hospital Erlangen, Germany)

BACKGROUND

Contact urticaria (CU) is an infrequent, mostly occupational disease that may be life-threatening (CU syndrome stage 4).

OBJECTIVES

To identify the current frequency, elicitors and cofactors of CU.

PATIENTS

Three cohorts were retrospectively analysed for CU: (a) patients from the Information Network of Departments of Dermatology (IVDK) database (2000-2014; n = 159 947); (b) patients from an allergy unit (Department of Dermatology, University Hospital Erlangen, 2000-2015; n = 4741); and (c) patients from the Anaphylaxis Registry (2007-2015: 6365 reported cases, including 2473 patients with Ring and Messmer grade III-IV reactions) for severe cases with skin/mucosal manifestations occurring at the workplace vs cases not occurring at the workplace (n = 68 vs n = 1821).

RESULTS

Four hundred and forty-eight CU patients (0.28%) were diagnosed in the IVDK cohort, and 16 (0.34%) (10 of immunological aetiology, and 6 of non-immunological aetiology) in the Erlangen cohort. The most frequent elicitors in the IVDK cohort were cosmetics, creams, sun protection agents (although these were less frequent in CU patients than in controls without CU; 26.8% vs 35.6%, P < .0001), and gloves (significantly more frequent in CU patients than in controls; 18.1% vs 6.5%, P < .0001). The most frequent elicitors in the Erlangen cohort were natural rubber latex and sorbic acid. Among the MOAHLFA index characteristics, in both cohorts occupational disease was more common in CU patients than in patients without CU. CU was significantly associated with allergic rhinitis and allergic asthma. Wet work was a relevant cofactor. In the Anaphylaxis Registry, 19 cases (0.3%) were identified with severe reactions including skin symptoms at the workplace linked to common occupational elicitors.

CONCLUSIONS

CU is a rare occupational skin manifestation with a frequency of <0.4% in the examined patients; it may, however, progress to anaphylaxis. Preventive measures are important, and should take into account the identified elicitors and cofactors.

Profile Shift in Latex Sensitization over the Last 20 Years

BACKGROUND

Natural rubber latex (NRL) allergy is commonly diagnosed according to medical history, skin allergy tests, and serological analyses. However, skin tests are increasingly being abandoned because of (i) their time-consuming nature, (ii) latex preparations for skin tests being not commercially available, and (iii) the use of in-house prepared test solutions is becoming ever more difficult due to increasing regulatory hurdles. In this light, we have evaluated differences in the profiles of current and former patients with suspected latex allergy.

METHODS

Sera of skin test-positive patients from a historic cohort (1995-2001, n = 149 patients) and currently (2014-2015, n = 48 patients) were simultaneously analyzed for specific IgE to latex by ImmunoCAP. If the serological screening was positive (≥0.35 kU/L), component-resolved diagnostics including profilins and cross-reactive carbohydrate determinants (CCDs) were performed.

RESULTS

In contrast to 88% (131/149) of the skin test-positive patients from the 1990s, only 51.1% (24/47) of the current cohort were found positive for specific IgE to latex. While 48.3% (72/149) of the patients had a convincing positive history in the 1990s, current skin test-positive patients rarely reported a relevant medical history (8.5%, 4/47). Specific IgE levels to latex were significantly higher in former patients with suspected latex allergy (p < 0.001) than in former sensitized individuals without allergy. However, this significant difference was lost in current allergic and sensitized patients with positive skin tests.

CONCLUSION

Sensitization profiles in patients with latex allergy have changed significantly over the last 2 decades. Discrimination between NRL sensitization and clinical allergy remains a diagnostic challenge. Our data highlight the need for a combination of all 3 criteria, i.e., patient history, skin test, and analysis of specific IgE, for a correct diagnosis of latex allergy.

Opportunities and obstacles in translating evidence to policy in occupational asthma

PURPOSE

Occupational asthma (OA), a common respiratory disorder in Western countries, is caused by exposures at the workplace. It is part of a broader definition of work-related asthma (WRA) that also includes pre-existing asthma aggravated by substances present in the workplace environment, and it is potentially preventable. The purpose of this paper is to illustrate preventive measures for occupational asthma by case studies.

METHODS

In three case studies we discuss preventive measures that have been associated with reductions in incidence of occupational asthma from natural rubber latex and from diisocyanates as supported by published literature. We also discuss challenges in relation to asthma from cleaning products in healthcare work.

RESULTS AND CONCLUSIONS

Several preventive measures have been associated with reduction in incidence of occupational asthma from natural rubber latex and from diisocyanates, and may provide lessons for prevention of other causes of occupational asthma. Cleaning products remain an unresolved problem at present with respect to asthma risks but potential measures include the use of safer products and safer applications such as avoidance of spray products, use of occupational hygiene methods such as improving local ventilation, and when appropriate, the use of personal protective devices.

Latex immunotherapy: evidence of effectiveness

INTRODUCTION

The only etiological and decisive therapy, able to influence the natural history of latex allergy is the specific desensitization.

AIM

To verify the clinical efficacy and immunological changes determined by latex sublingual immunotherapy in allergic patients who underwent this treatment for at least 3 years.

MATERIAL AND METHODS

We enrolled 76 patients (16 males and 60 females, mean age 34 years old) with evidence of a natural rubber latex allergy. To assess the effectiveness of the immunotherapy we performed a latex skin prick test, specific IgE and IgG4 and challenge tests before and after at least 3 years of desensitization.

RESULTS

We observed a reduction in the mean diameter of the wheal area at the skin prick test and a decrease in latex specific IgE while no significant changes of latex IgG4 values were found. Moreover a reduction of symptoms and scores at the provocation tests were remarked.

CONCLUSIONS

Although the primary prevention (which still remains the gold standard treatment for patients suffering from the latex allergy) sublingual immunotherapy can be offered with efficacy in addition to symptomatic treatment to selected patients.

Quantification of protein and latex allergen content of various natural rubber latex products

Introduction: The use of natural rubber latex (NRL) products can cause IgE-mediated allergic reactions in exposed people. The aim of this study was to quantify the content of protein and latex allergens of currently available NRL products to estimate the allergenic potential of these products. Methods: 14 household articles (pacifiers, baby bottle nipples, condoms, household and disposable gloves, toy balloons, and Band-Aids) as well as 18 NRL examination gloves currently used by healthcare workers were investigated. Extracts of the examination gloves were prepared according to the standard method DIN EN 455-3, which contains requirements and testing for biological evaluation of single use medical gloves. The protein content was determined with a modified Lowry method. Latex allergen content was measured using an IgE-inhibition immunoassay with a mix of serum-sensitized patients as detection antibody sources and the latex ImmunoCAP as solid phase. The allergens Hev b 1, 3, 5, and 6.02 were determined using available immunoassays. Results: In 5 out of 18 examination gloves, the protein content was under the detection limit. The other 13 gloves contained protein between 7.1 and 92.3 µg protein/g material. Five glove brands contained protein concentrations above the recommended reference value of 30 µg protein/g material. Latex allergen could be measured in 12 out of 18 NRL gloves. In only 3 gloves could none of the allergens Hev b 1, 3, 5, and 6.02 be detected. Protein and Hev b 1 could be measured in the examined childcare products, while the concentrations of the latex allergens Hev b 3, 5, and 6.02 were mostly under the detection limit. Boiling of childcare products led to a reduction of protein and allergen content. In some of the other daily-used NRL articles, the protein and allergen contents were even higher than in gloves. Conclusion: Our study demonstrated that protein, and particularly latex allergens, were detectable in currently available examination gloves as well as in household articles whereby a risk for sensitization and/or induction of allergic symptoms could not be excluded.

Occupational contact urticaria: lessons from the French National Network for Occupational Disease Vigilance and Prevention (RNV3P)

BACKGROUND

Occupational contact urticaria (OCU) is an occupational contact dermatitis that can cause serious health consequences and disability at work.

OBJECTIVES

To describe OCU and its temporal trends by the main causal agents and activity sectors in a nationwide scheme in France.

METHODS

Using data from the French National Network for Occupational Disease Vigilance and Prevention (RNV3P), we described OCU reported during the period 2001-10 and analysed the temporal trends of OCU and OCU attributed to the most frequent agents over the study period. Trends analyses were supported by reporting odds ratios using a logistic regression model with reference to 2001, or with time as a continuous variable.

RESULTS

During the study period, 251 cases of OCU were reported in RNV3P, half of which were due to natural rubber latex, in particular in the health and social work activity sector (HSW). The number of these cases declined significantly over the study period (19% per year), and particularly after 2006. Conversely, the other causes of OCU did not decrease.

CONCLUSIONS

Using surveillance data from a French national network, this study has found that there was a significant decline in OCU due to natural rubber latex, particularly in the HSW, when powdered latex gloves were banned from French hospitals. Our results show the effectiveness of this preventive measure, and suggest that this practice should be extended to other sectors.

Identification and practical management of latex allergy in occupational settings

Allergy to natural rubber latex (NRL) from Hevea brasiliensis is a relevant occupational health hazard. The use of gloves and products manufactured with latex and environmental allergen exposure in the work environment are risks factors for the development of occupational allergy among different job categories. Healthcare workers have been the most commonly affected, but other professions with exposure to latex products such as hairdressers, cleaners, food handlers and those making natural rubber latex (NRL) products are also at risk of developing occupational allergy. Clinical manifestations of IgE-mediated latex allergy can range from troublesome skin disorders to life-threatening systemic reactions. It is very important to identify the occupational allergic diseases in their early stages in order to implement avoidance strategies. For this purpose, the interventions for prevention should emphasize the importance of latex allergy awareness and surveillance among exposed workforces.

Occupational allergy: respiratory hazards in healthcare workers

PURPOSE OF REVIEW

Allergens are one group of respiratory hazards in the workplace of healthcare workers (HCWs). The purpose of this review is to summarize the recent advances in occupational allergy as well as potential hazardous agents in HCWs.

RECENT FINDINGS

The review covers new developments on the epidemiology, diagnosis and management of occupational allergy in HCWs. This article also provides updated information on the prevalence of work-related respiratory symptoms, as well as on respiratory hazards among healthcare providers.

SUMMARY

It is established that HCWs are at risk of asthma symptoms. The growing use of cleaning products is one of the causes of occupational airway disease in that group. Among healthcare professionals, the prevalence of asthma varies depending on worksite. Recent findings indicate a need for education among HCWs concerning occupational risks. A lack of knowledge of product components as well as about exposure to cleaning/disinfecting agents has been demonstrated. Further studies are necessary to determine the relative role of individual agents versus complex workplace exposures in the development of work-related asthma in HCWs.

Handling chemotherapy drugs-Do medical gloves really protect?

Due to their potential mutagenic, carcinogenic and teratogenic effects occupational exposure to chemotherapy drugs should be kept to a minimum. Utilization of personnel protective devices, especially the use of protective medical gloves, is a mainstay to avoid skin contact. The choice of appropriate gloves is of outstanding importance. For optimal protection in the oncology setting it is essential to establish general guidelines evaluating appropriate materials and defining quality standards. Establishing these guidelines can facilitate better handling and avoid potential hazards and late sequelae. In Europe there are no specific requirements or test methodologies for medical gloves used in the oncology environment. The implementation of uniform standards for gloves used while handling chemotherapy drugs would be desirable. In contrast, in the US medical gloves used to handle chemotherapy drugs have to fulfill requirements according to the ASTM International (American Society of Testing and Materials) standard D 6978-05. Nitrile or natural rubber latex is a preferred basic glove material, while vinyl is considered inappropriate because of its generally increased permeability. For extended exposure to chemotherapy drugs, double gloving, the use of thicker gloves and the frequent change of gloves increases their protective power.

Ten years incidence of natural rubber latex sensitization and symptoms in a prospective cohort of health care workers using non-powdered latex gloves 2000-2009

OBJECTIVES

To assess the incidence of sensitization and gloves-related symptoms in 10-year follow-up in a group of health care workers (9,660 person-years) using non-powdered latex gloves from 2000 to 2009 and to examine related factors.

MATERIALS AND METHODS

We studied 2,053 health care workers in Trieste Hospitals by means of skin prick test for latex extract, patch tests and medical examinations. We report the incidence of latex sensitization among workers using non-powdered latex gloves.

RESULTS

The incidence of latex sensitization, rhinitis, asthma, urticaria, irritant and allergic contact dermatitis were 1.0; 0.12; 0.21; 0.72; 2.39 and 2.50 cases per 1,000 person-years, respectively. Respiratory symptoms and urticaria were positively related with latex sensitization (OR = 8.0; 95 % CL 1.27-48.6), with common allergic respiratory symptoms (OR = 4.19; 95 % CL 1.04-16.8) and with familial atopy (OR = 4.47; 95 % CL 1.1-17.9).

CONCLUSION

The incidence of latex sensitization and latex-related symptoms were very low but subjects with allergic symptoms related to common allergens are at higher risk. The use of non-latex gloves is suggested for them.

Chlorhexidine and hypersensitivity reactions in dentistry

Immunological reactions to chlorhexidine, including allergy (Type I hypersensitivity) and allergic contact dermatitis/stomatitis (Type IV hypersensitivity), have been recognised for many years. This potential safety issue, however, is not well known within dentistry. The purpose of this paper is to alert dentists and dental care professionals to the potential of chlorhexidine in causing hypersensitivity reactions and to consider this possibility if unexplained hypersensitivity reactions occur.

Primary prevention of latex allergy in healthcare-spectrum of strategies including the European glove standardization

IgE-mediated allergy to natural rubber latex was first noted from rubber gloves in 1979. The initial reports in dermatological journals described contact urticarial reactions; later, severe generalized allergic reactions and asthma were documented. A considerable proportion of the people involved in medical and dental care were found to be sensitized to latex. This article describes and surveys a broad range of primary prevention measures at the local and national levels. Examples are given from paediatrics, dental education, and medical care. National strategies and position papers on latex allergy are presented in which medical professionals, manufacturers and public authorities have cooperated. Special reference is paid to the European work to standardize medical gloves, which led to document EN 455:3.

Randomized, double-blind, placebo-controlled clinical trial of sublingual immunotherapy in natural rubber latex allergic patients

BACKGROUND

Natural rubber latex allergy is a common and unsolved health problem. Since the avoidance of exposure is very difficult, immunotherapy is strongly recommended, but before its use in patients, it is essential to prove the efficacy and safety of extracts.The aim of the present randomised, double-blind, placebo-controlled clinical trial was to assess the efficacy and tolerability of latex sublingual immunotherapy in adult patients undergoing permanent latex avoidance.

METHODS

Twenty-eight adult latex-allergic patients (5 males and 23 females), with mean age of 39 years (range 24-57) were randomized to receive a commercial latex-sublingual immunotherapy or placebo during one year, followed by another year of open, active therapy. The following outcomes were measured at baseline and at the end of first and second year of follow-up: skin prick test, gloves-use score, conjunctival challenge test, total and specific IgE, basophil activation test, and adverse reactions monitoring.

RESULTS

No significant difference in any of the efficacy in vivo variables was observed between active and placebo groups at the end of the placebo-controlled phase, nor when each group was compared with their baseline values at the end of the two year-study. An improvement in the average percentage of basophils activated was observed. During the induction phase, 4 reactions in the active group and 5 in the placebo group were recorded. During the maintenance phase, two patients dropped out due to pruritus and to acute dermatitis respectively.

CONCLUSION

Further studies are needed to evaluate latex-sublingual immunotherapy, since efficacy could not be demonstrated in adult patients with avoidance of the allergen.

TRIAL REGISTRATION NUMBER

ACTRN12611000543987.

Latex medical gloves: time for a reappraisal

Many hospitals have implemented policies to restrict or ban the use of devices made of natural rubber latex (NRL) in healthcare as precautionary measures against the perceived risk of NRL allergy. Changes in glove technology, progress in measuring the specific allergenic potential of gloves and a dramatic decrease in the prevalence of NRL allergies after interventions and education prompted us to revisit the basis for justifiable glove selection policies. The published Anglophone literature from 1990 to 2010 was reviewed for original articles and reviews dealing with the barrier and performance properties of NRL and synthetic gloves and the role of glove powder. The review shows that NRL medical gloves, when compared with synthetic gloves, tend to be stronger, more flexible and better accepted by clinicians. The introduction of powder-free gloves has been associated with reductions in protein content and associated allergies. Recently, new methods to quantify clinically relevant NRL allergens have enabled the identification of gloves with low allergenic potential. The use of low-protein, low-allergenic, powder-free gloves is associated with a significant decrease in the prevalence of type I allergic reactions to NRL among healthcare workers. Given the excellent barrier properties and operating characteristics, dramatically reduced incidences of allergic reactions, availability of specific tests for selection of low-allergen gloves, competitive costs and low environmental impact, the use of NRL gloves within the hospital environment warrants reappraisal.

Trends in occupational airway diseases in German hairdressers: frequency and causes

BACKGROUND

Hairdressers are exposed to several allergens and irritants known to cause obstructive airway diseases (OAD). In the early 1990s, high incidence rates of OAD were observed in German hairdressers. It was expected that modification of formulations would resolve the problem of high OAD rates in hairdressers.

METHODS

The numbers of confirmed cases are reported of allergen-, latex- and irritant-induced OAD in German hairdressers, as registered by the responsible compensation board during 1998 and 2007. Hairdressing components reported as causative for OAD in hairdressers were analyzed. The incidence rates of OAD in hairdressers were compared with rates in healthcare professionals, as both occupations had high rates of OAD in the 1990s.

RESULTS

From 1998 until 2003, the total number of confirmed cases of allergen-, latex- and irritant-induced OAD stayed at a plateau of 60 cases annually in hairdressers, after which a downward trend was apparent. The number of irritant-induced OAD cases did not fall during this overall downward trend. Hair dyes and acid perms were most often identified as the substances causing OAD in hairdressers. In healthcare professionals, the downward trend in OAD is more pronounced than in hairdressers, mainly due to a decrease in latex-induced cases.

CONCLUSIONS

The number of allergen- and irritant-induced cases of OAD in German hairdressers is still high. Exposure to known airway irritants is still occurring in spite of modification of the formulations. Continuous medical surveillance of hairdressers is recommended, in order to detect individual susceptibility, especially in apprentices.