Changes in rates of natural rubber latex sensitivity among dental school students and staff members after changes in latex gloves

Reduced protein levels in latex gloves may play an alternative approach to lowering latex sensitization risks among health workers; a cross-sectional analytical study

BACKGROUND

Latex gloves are essential for protecting healthcare workers from biological hazards but pose a risk of latex allergy, particularly due to powdered, protein, and allergen content. Recent advancements in latex glove manufacturing have led to reduced levels of extractable proteins, a known factor triggering allergenic reaction. This study aimed to compare latex sensitization between nursing staff using low-protein and high-protein latex gloves at a tertiary university hospital in Thailand.

METHODS

A cross-sectional analytical study categorized participants into two groups based on glove exposure: the low extractable protein group (only exposed to non-powdered latex gloves with extractable protein levels below 50 µg/g) and the high extractable protein group (exposed to powdered latex gloves with levels above 50 µg/g). The sample size comprised 163 individuals in the low protein group and 318 in the high protein group (1:2). Latex allergy symptoms and sensitization were assessed using a self-administered questionnaire and latex-specific IgE measurement (ImmunoCAP), respectively. Data analysis involved descriptive and inferential statistics, including odds ratios and 95%CI.

RESULTS

Demographic data was mostly similar in both exposure groups except for age. No significant differences in latex sensitization between the low and high protein groups were found via latex-specific IgE measurement (crude OR 1.90, 95%CI: 0.5, 7.18), potentially attributed to lower extractable protein levels in powdered latex gloves compared to previous studies. In contrast, the low protein group exhibited significantly fewer current latex allergy symptoms in both bivariate (crude OR 0.24, 95%CI: 0.06, 0.74) and multiple variable analysis (adjusted OR 0.18, 95%CI: 0.04, 0.86). Moreover, there was a significant reduction in latex allergy symptoms among the low protein group, decreasing from 9.8% who reported experiencing symptoms (when powdered latex gloves were used) to 1.2% who still reported current symptoms (OR 0.11, 95%CI: 0.02, 0.44).

CONCLUSIONS

This study underscores the importance of using non-powdered and low-protein latex gloves to reduce latex allergy symptoms while emphasizing the need for further investigation into the relationship between extractable protein levels in addition to the attempt of the major allergen removal and latex sensitization amid evolving glove manufacturing practices.

Latex Allergy in Children

Notwithstanding the efforts made in the last decades to mitigate the consequences of natural rubber latex allergy, this disease continues to be a major health problem, especially in developing countries. The categories of patients with greater and frequent exposure to latex (such as health care professionals and, in the pediatric field, subjects who undergo repeated surgery, e.g., those suffering from spina bifida and urogenital malformations) have an increased risk of developing sensitization and allergy to latex. Herein we provide an overview of the current knowledge and practical recommendations with a focus on epidemiology, diagnostics, and management (including both prevention and therapy) in order to guide a correct recognition and containment of this potentially fatal condition.

An electrochemical paper-based analytical sensor for one-step latex protein detection

A proposed simple electrochemical paper-based analytical sensor offered one-step latex protein detection by measuring remaining copper after online protein complexation

ICON: Diagnosis and management of allergic conjunctivitis

Ocular allergy (OA), interchangeably known as allergic conjunctivitis, is a common immunological hypersensitivity disorder affecting up to 40% of the population. Ocular allergy has been increasing in frequency, with symptoms of itching, redness, and swelling that significantly impacts an individual's quality of life (QOL). Ocular allergy is an often underdiagnosed and undertreated health problem, because only 10% of patients with OA symptoms seek medical attention, whereas most patients manage with over-the-counter medications and complementary nonpharmacological remedies. The clinical course, duration, severity, and co-morbidities are varied and depend, in part, on the specific ocular tissues that are affected and on immunologic mechanism(s) involved, both local and systemic. It is frequently associated with allergic rhinitis (commonly recognized as allergic rhino conjunctivitis), and with other allergic comorbidities. The predominance of self-management increases the risk of suboptimal therapy that leads to recurrent exacerbations and the potential for development of more chronic conditions that can lead to corneal complications and interference with the visual axis. Multiple, often co-existing causes are seen, and a broad differential diagnosis for OA, increasing the difficulty of arriving at the correct diagnosis(es). Ocular allergy commonly overlaps with other anterior ocular disease disorders, including infectious disorders and dry eye syndromes. Therefore, successful management includes overcoming the challenges of underdiagnosis and even misdiagnosis by a better understanding of the subtleties of an in-depth patient history, ophthalmologic examination techniques, and diagnostic procedures, which are of paramount importance in making an accurate diagnosis of OA. Appropriate cross-referral between specialists (allergists and eyecare specialists) would maximize patient care and outcomes. This would significantly improve OA management and overcome the unmet needs in global health.

Occupational rhinitis and occupational asthma: Association or progression?

BACKGROUND

Occupational asthma is the most frequently reported occupational respiratory disease in registries, and is often co-diagnosed with occupational rhinitis. We undertook a systematic review of the English-language epidemiologic literature linking these two conditions, with emphasis on progression from occupational rhinitis to occupational asthma.

METHODS

PubMed and Embase were queried in a series of structured searches designed to identify studies comparing occupational asthma and occupational rhinitis incidence or prevalence in occupationally exposed individuals.

RESULTS

The searches yielded a total of 109 unique citations, 15 of which yielded inferential data on the occupational rhinitis-asthma relationship. Nine of fifteen studies showed statistically significant associations between the occurrence of occupational rhinitis and occupational asthma among individual workers.

CONCLUSIONS

Limited data support the notion that occupational rhinitis precedes the development of occupational asthma, particularly when high-molecular-weight (HMW) agents are involved. The relationship between the two conditions could not be evaluated in many relevant studies due to a lack of cross-tabulation of individual cases.

Atopic status and latex sensitization in a cohort of 1,628 students of health care faculties

BACKGROUND

Atopic diseases have increased since the second half of the previous century. Atopic workers are at higher risk to be sensitized to latex, and the first years of exposure are supposed to be especially risky.

OBJECTIVE

To assess atopic status and rate of latex sensitization in health care students starting their exposure to latex gloves.

METHODS

We analyzed medical surveillance data from 1,628 health care students from 2010 to 2016. Students completed a questionnaire focused on their previous and current latex exposure and personal and family histories of allergic diseases; underwent skin prick testing with common allergens and latex extract (and/or total and latex-specific immunoglobulin E in serum); and underwent a medical examination.

RESULTS

Skin prick test results for common inhalant allergens showed that 807 of 1,628 students (49.6%) had atopy. Atopy by skin prick testing was associated with male sex (odds ratio 1.49, 95% confidence interval 1.18-1.86), a personal history of oculorhinitis or asthma (odds ratio 10.22, 95% confidence interval 7.4-14.13), and atopic eczema (odds ratio 1.87, 95% confidence interval 1.05-3.36) at multivariate regression analysis. Eleven students (0.7% of total population) were found to be sensitized to latex and all had atopy.

CONCLUSION

Despite the high prevalence of atopy in health care students of Trieste, the latex sensitization rate is very low and comparable to general population. This is reasonably due to the low exposure to latex gloves at the time of the evaluation and to low latex release from the gloves currently used in our hospital.

Natural rubber latex allergy: implications for the orthodontist

Natural rubber latex (NRL) allergy can have potentially serious consequences, and reports of orthodontic patients reacting to NRL have increased significantly over recent years. It is therefore important for the orthodontist to know how to manage patients with an NRL allergy and how to deal with possible reactions to NRL. Safe and effective practice depends on recognizing patients who are at risk of NRL allergy, and an awareness of materials and equipment that contain NRL and the availability of suitable NRL-free alternatives.

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.

Risk factors associated with asthma phenotypes in dental healthcare workers

BACKGROUND

Exposure in the dental environment can increase the risk of respiratory disease in dental healthcare workers (HCWs). This study investigated the prevalence of asthma phenotypes in dental HCWs and associated risk factors.

METHODS

A cross-sectional study of 454 dental HCWs in five dental institutions in South Africa was conducted. A self-administered questionnaire elicited the health and employment history of subjects. Sera was analyzed for atopic status and latex sensitization. Pre- and post-bronchodilator spirometry was performed.

RESULTS

The prevalence of atopic asthma was 6.9%, non-atopic asthma 5.9% and work-exacerbated asthma (WEA) 4.0%. Atopy and work-related ocular-nasal symptoms were strong predictors of WEA (OR: 3.4; 95% CI: 1.07-10.8; OR: 6.7, 95% CI: 2.4-19.1), respectively. Regular use of personal protective equipment (PPE) was associated with a protective affect (OR: 0.23, 95% CI: 0.1-0.7) among non-atopic asthmatics, while glove use and respiratory protection was protective among atopic asthmatics (OR: 0.39, 95% CI: 0.17-0.89).

CONCLUSION

Identification of risk factors associated with specific asthma phenotypes in dental HCWs can be used to focus preventive strategies for asthmatics.

Occupational hazards to dental staff

Dental professionals are predisposed to a number of occupational hazards. These include exposure to infections (including Human Immunodeficiency Virus and viral hepatitis); percutaneous exposure incidents, dental materials, radiation, and noise; musculoskeletal disorders; psychological problems and dermatitis; respiratory disorders; and eye insults. Percutaneous exposure incidents remain a main concern, as exposure to serious infectious agents is a virtual risk. Minimizing percutaneous exposure incidents and their consequences should continue to be considered, including sound infection control practices, continuing education, and hepatitis B vaccination. Basically, for any infection control strategies, dentists should be aware of individual protective measures and appropriate sterilization or other high-level disinfection utilities. Strained posture at work disturbs the musculoskeletal alignment and leads to stooped spine. The stooped posture also involved certain groups of muscles and joints. This may lead to diseases of the musculoskeletal system. Continuous educating and appropriate intervention studies are needed to reduce the complication of these hazards. So, it is important for dentists to remain constantly up-to-date about measures on how to deal with newer strategies and dental materials, and implicates the need for special medical care for this professional group.

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.

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.

Interdigitated capacitive biosensor based on molecularly imprinted polymer for rapid detection of Hev b1 latex allergen

Allergen protein detection was performed by a surface imprinted layer combined with an interdigitated capacitance (IDC) transducer that allowed label-free measurements. The immobilized imprinted polymers are the probes that bind to rubber allergen proteins extracted from products such as rubber gloves. Copolymers made from methacrylic acid-vinylpyrrolidone-dihydroxyethylene-bisacrylamide (MAA-NVP-DHEBA) are soluble in aqueous solution and eliminate the denaturation of protein. When deposited as a coating onto an IDC microelectrode transduction system, such materials lead to sensors that produce capacitance responses that are clearly dependent on the concentration of the latex protein (10-900 ng ml(-1)) in pH 7.4 buffer. The biosensor can detect Hev b1 within minutes and with a detection limit of 10 ng ml(-1). Different but related hevein allergenic proteins isolated from natural rubber latex from the rubber tree (Hev b1, Hev b2, and Hev b3) were distinguished by the imprinted material, depending on the dimension and conformation of these proteins with a selectivity factor of 4. They recognized Hevea latex proteins better than non-Hev b proteins, such as lysozyme, ovalbumin, and bovine serum albumin, by a factor of 2. Moreover, the sensor exhibited good operational stability of up to 180 days when used continuously at room temperature.

Occupational asthma: what can be done to prevent it?

Occupational asthma (OA) accounts for at least 10% of cases of adult asthma and presents as intermittent asthma occurring at the workplace and remitting on weekends and holidays, or persistent asthma, especially if the diagnosis and early intervention is delayed. OA is under-recognized, challenging and time-consuming to diagnose, difficult to confirm with currently available tests and complex in terms of legal implications of disability and impairment. Over 400 agents have been identified as causing OA with allergic triggers accounting for 80-90% of cases. Managing the worker with OA is demanding as it requires the most thorough evaluation with attention to detail to provide an accurate diagnosis and develop a thoughtful treatment recommendation. This frequently has to occur in the context of various competing entities including management, unions, insurance carriers and attorneys. The primary goal is excellent employee health through interventions that may allow the worker to continue in their occupation safely. Primary, secondary and tertiary prevention measures have been adopted for various types of OA with success. Novel approaches may become available and be beneficial to identify and treat OA early before severe, chronic, unremitting and irreversible changes occur.

Occupational asthma: risk factors, diagnosis and preventive measures

In adulthood, new or recurrent asthma is caused by work in approximately 10% of cases. The term occupational asthma is reserved for those cases arising from respiratory hypersensitivity to a specific workplace agent; in others (work-exacerbated asthma) the mechanism is of nonspecific airway irritation on a background of bronchial hyper-reactivity. Some 300 workplace agents are capable of inducing asthma de novo; fortunately, most cases are attributed to a much smaller number to which exposure occurs in a few high-risk occupations. Exposure level is the most important remediable risk factor; the factors governing individual susceptibility are poorly understood. Diagnosis is generally straightforward. Management is rarely pharmacologic and often difficult since the diagnosis incurs important employment and other social consequences.

EAACI position paper on occupational rhinitis

The present document is the result of a consensus reached by a panel of experts from European and non-European countries on Occupational Rhinitis (OR), a disease of emerging relevance which has received little attention in comparison to occupational asthma. The document covers the main items of OR including epidemiology, diagnosis, management, socio-economic impact, preventive strategies and medicolegal issues. An operational definition and classification of OR tailored on that of occupational asthma, as well as a diagnostic algorithm based on steps allowing for different levels of diagnostic evidence are proposed. The needs for future research are pointed out. Key messages are issued for each item.

Making the diagnosis of occupational asthma: when to suspect it and what to do

Although most adult patients seen by a clinician are employed, medical school curricula and residency training rarely cover occupational exposures and resultant diseases, even common ones that are encountered in a typical medical practice. This primer on occupational asthma is intended for the primary care clinician to provide the essential tools to diagnose and treat airways disease in the workplace. Using a case vignette format, we review the basic approach to suspecting and establishing a diagnosis of occupational asthma and address the thornier question of what to do about it. After reviewing this primer, the reader will be able to routinely include occupational asthma as part of the differential diagnoses in the adult patient with new or worsened asthma.

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.

Prevention of occupational asthma in Ontario

Occupational asthma continues to be one of the most common occupational lung diseases in industrialized areas. Primary and secondary preventive measures have been well described, but there are relatively few studies to support the effectiveness of such measures, although the benefits of tertiary measures such as early recognition and removal from further exposure to a causative sensitizing agent are well recognized. In Ontario, a combined approach of preventive measures has shown effectiveness in allergy and asthma from occupational exposure to natural rubber latex. In addition, a program to reduce exposure to diisocyanates and introduce medical surveillance was associated with earlier diagnosis and fewer cases in a compensation population. However there remain barriers to the early diagnosis of occupational asthma in Ontario, especially in workers of lower education and lower income. In addition, there is recognized need for further physician education to allow early suspicion and diagnosis of occupational asthma.

Respiratory effects of exposure to methacrylates among dental assistants

BACKGROUND

Case reports of occupational asthma in dental personnel have been published, but there is little data on the risk of respiratory disorders related to occupational exposure to methacrylates in dental assistants. The objective of this study was to investigate the relation of exposure to methacrylates to occurrence of respiratory symptoms and diseases among dental assistants.

METHODS

A cross-sectional study of female dental assistants from the membership register of the Finnish Association of Dental Hygienists and Assistants was conducted in the Helsinki metropolitan area. A CATI was carried out to collect information on health and exposures. A total of 799 dental assistants participated (response rate 87%).

RESULTS

Daily use of methacrylates was related to a significantly increased risk of adult-onset asthma (adjusted OR 2.65, 95% CI 1.14-7.24), nasal symptoms (1.37, 1.02-1.84), and work-related cough or phlegm (1.69, 1.08-2.71). Nasal symptoms showed a dose-response relation with increasing years of exposure to methacrylates, and those with >10 years of exposure had also increased risk of hoarseness, dyspnoea, and wheezing with dyspnoea. Dental assistants with a history of atopic diseases were particularly susceptible to exposure to methacrylates, the adjusted OR for adult asthma being in this group 4.18 (95% CI 1.02-28.55) and for nasal symptoms 2.11 (1.08-4.19).

CONCLUSIONS

This study provides new evidence that the risk of adult-onset asthma, nasal symptoms and other respiratory symptoms increase significantly with daily use of methacrylates in dental assistants' work. The results suggest that exposure to methacrylates poses an important occupational hazard for dental assistants.

Latex allergy in the prehospital setting

INTRODUCTION

Latex allergy first was recognized early in the 20th Century, but was not a matter of concern until the last decade of that Century. The reported incidence of latex allergy in different occupations varies considerably. It has been documented in dental workers, operating theater staff, anesthetists, and laboratory technicians. However, little data specifically related to those involved in patient care in the emergency prehospital setting are available.

METHODS

A questionnaire was distributed to a sample of both volunteer and salaried first responders from St. John Ambulance Australia in South Australia and Western Australia, and the South Australian Ambulance Service. The first responders were surveyed to: (1) determine the incidence of latex allergy; (2) consider possible factors associated with its development; (3) compare characteristics of the surveyed groups; and (4) reinforce the development of an educational program. The study tool had predetermined statistical qualities. Data were collated and processed using standard statistical procedures. Surveys were collected anonymously.

RESULTS

Of the 2,716 forms distributed, 1,099 were returned, resulting in an overall response rate of 40.5%. Atopy was identified in 14.9% of participants, hand dermatitis in 9.4%, and latex allergy in 6.4%. In the group of full-time ambulance officers, there was a significantly higher incidence of hand dermatitis and latex allergy. There also was a significant relationship between latex allergies and both dermatitis and glove usage (as measured by frequency and duration).

CONCLUSION

In a group of first responders assessed by an anonymous, voluntary questionnaire, the subset of full-time, salaried ambulance officers was identified as having a higher incidence of hand dermatitis and latex allergy than their volunteer co-workers. These results require further assessment to substantiate the frequency of latex allergy and determine the predisposing factors. All personnel must learn about hand care. Non-powdered, natural rubber latex gloves should be supported for general use in this setting.

Prevention of occupational asthma--practical implications for occupational physicians

BACKGROUND

Occupational factors have been estimated to contribute to approximately 10% of adult-onset asthma and occupational asthma (OA) is one of the most common occupational lung diseases in industrialized areas. Persistent asthma frequently occurs with significant socio-economic impacts.

METHODS

A literature search was performed using PubMed. The key term searched was occupational asthma combined with prevention.

RESULTS

Primary prevention has been effective for OA related to natural rubber latex, and may have reduced the incidence of diisocyanate-induced asthma. Medical health surveillance has been effective in settings such as the detergent enzyme industry, workers exposed to complex platinum salts and likely for diisocyanate workers in Ontario. Tertiary prevention is still required for workers with OA and can improve prognosis.

CONCLUSIONS

OA is potentially preventable. Sufficient studies have demonstrated the rationale and benefit of primary preventive strategies. Medical health surveillance programs combined with occupational hygiene measures and worker education have been associated with improved outcomes but further studies are needed to understand the optimum frequency and measures for such programs and to identify the separate contribution of the components. Until primary and secondary prevention is better understood and implemented, there will also remain a need for tertiary preventive measures.

Primary prevention of latex related sensitisation and occupational asthma: a systematic review

METHODS

Eight primary prevention intervention studies on natural rubber latex (NRL) published since 1990 were identified and reviewed. This is the largest evidence base of primary prevention studies for any occupational asthmagen.

RESULTS

Review of this small and largely observational evidence base supports the following evidence statement: Substitution of powdered latex gloves with low protein powder-free NRL gloves or latex-free gloves greatly reduces NRL aeroallergens, NRL sensitisation, and NRL-asthma in healthcare workers. Evidence in support of this statement is ranked SIGN level 2+, referring to well conducted case-control or cohort studies with a low risk of confounding, bias, or chance and a moderate probability that the relationship is causal.

CONCLUSION

Substitution of powdered latex gloves with low protein powder-free NRL gloves or latex-free gloves promises benefits to both workers' health and cost and human resource savings for employers. This message should be broadly disseminated beyond the hospital sector to include other healthcare settings (such as aged care facilities) as well as food service and other industries where latex gloves might be used.

Latex allergy: a follow up study of 1040 healthcare workers

BACKGROUND

Natural rubber latex allergy can cause skin and respiratory symptoms The aim of this study was to evaluate the prevalence and incidence of latex related symptoms and sensitisation among a large group of healthcare workers in Trieste hospitals, followed for three years before and after the introduction of powder-free gloves with low latex release.

METHODS

In the years 1997-99 the authors evaluated 1040 healthcare workers exposed to latex allergen for latex related symptoms and sensitisation by means of a questionnaire, a medical examination, skin prick tests, and IgE specific antibody assay. The second evaluation was carried out in the years 2000-02, subsequent to the changeover to a powder-free environment.

RESULTS

Glove related symptoms were seen in 21.8% of the nurses (227), mostly consisting of mild dermatitis: 38 (3.6%) complaining of contact urticaria and 24 (2.3%) of asthma and/or rhinitis. These symptoms were significantly related to skin prick tests positive to latex (OR = 9.70; 95% CI 5.5 to 17) and to personal atopy (OR = 2.29; 95% CI 1.6 to 3.2). Follow up was completed in 960 subjects (92.3%): 19 new subjects (2.4%) complained of itching erythema when using gloves, but none was prick positive to latex. Symptoms significantly improved and in most cases disappeared (p<0.0001).

CONCLUSIONS

Simple measures such as the avoidance of unnecessary glove use, the use of non-powdered latex gloves by all workers, and use of non-latex gloves by sensitised subjects can stop the progression of latex symptoms and can avoid new cases of sensitisation.

Alergia al látex

OBJECTIVE

To review the etiology, diagnosis, prevention and treatment of latex allergy in the hospital setting, and to establish a list of potentially hazardous drugs.

METHOD

A literature search was performed. A guide about latex-containing drugs (any component) was developed by contacting manufacturers.

RESULTS

The most relevant factor for latex sensitization is exposure extent. Regarding diagnosis the medical history and skin testing are crucial; regarding secondary prevention, identifying the various at-risk groups. Immunotherapy is currently considered a valid option for the management of this condition.

CONCLUSIONS

The development of a guide listing latex-containing drugs is essential for the primary prevention of allergic reactions to this substance in hospital.

Grand rounds: latex-induced occupational asthma in a surgical pathologist

CONTEXT

Latex allergy and sensitization have been an important problem facing health care workers. Providing a latex-safe environment is the intervention of choice.

CASE PRESENTATION

A 46-year-old surgical pathologist presented with increasing shortness of breath for the previous 4 years. Twenty years before presentation, he noted a pruritic, erythematous rash on his hands, associated with latex glove use. Fourteen years before presentation, during pathology residency, he developed a nonproductive cough, wheezing, and an urticarial rash, temporally associated with use of powdered latex gloves. These symptoms improved while away from work. At presentation, he had one-flight dyspnea. His skin prick test was positive for latex, and pulmonary function testing showed mild obstruction, which was reversible with bronchodilator use. Because the patient was at risk for worsening pulmonary function and possible anaphylaxis with continued exposure, he was removed from the workplace because no reasonable accommodation was made for him at that time.

DISCUSSION

The patient's presentation is consistent with latex-induced occupational asthma. Initially noting dermal manifestations, consistent with an allergic contact dermatitis secondary to accelerators present in latex gloves, he later developed urticaria, flushing, and respiratory symptoms, consistent with a type I hypersensitivity reaction to latex. He also has reversible airways disease, with significant improvement of peak expiratory flow rate and symptoms when away from work.

RELEVANCE TO CLINICAL OR PROFESSIONAL PRACTICE

The ideal treatment for latex sensitization is removal from and avoidance of exposure. Clinicians should consider occupational asthma when patients present with new-onset asthma or asthmatic symptoms that worsen at work.

Occupation-related allergies in dentistry

BACKGROUND

Allergies to natural rubber latex (NRL) were unknown in dentistry until 1987. That changed with the publication of a report documenting NRL-based anaphylaxis in a dental worker. This case and others prompted regulatory and manufacturing changes in rubber products and increased awareness throughout the profession. However, other common dental chemicals cause allergic reactions and irritation and often are handled with insufficient precautions. Although recognition of NRL allergy has improved, awareness of other potential allergens and irritants in dentistry still is limited.

OVERVIEW

Recent research indicates that the prevalence of NRL protein allergy may be decreasing. In contrast, occupation-related dermatoses associated with other dental products may be more common. Encounters with bonding agents, disinfectants, rubber, metals and detergents can cause occupation-based irritant contact dermatitis and allergic contact dermatitis. These conditions may be found in more than one-quarter of dental and medical personnel. Therefore, dental-specific information about the recognition and management of allergic and irritant reactions is needed.

CONCLUSIONS AND CLINICAL IMPLICATIONS

The prevalence of occupation-related dermatitis may be increasing in dentistry. Reducing exposure to potential irritants and allergens and educating personnel about proper skin care are essential to reversing this trend.

Occupational allergens in dentistry

PURPOSE OF REVIEW

Dental professionals and their physicians frequently do not recognize, accurately diagnose or appropriately manage occupational allergies. Dental allergen identification, diagnostics and practical avoidance strategies are summarized in this review.

RECENT FINDINGS

Methacrylates, natural rubber latex proteins, rubber glove allergens, and glutaraldehyde are the predominant allergens in dentistry. Reactions range from cell-mediated contact allergy to urticaria and occupational asthma.

SUMMARY

Despite recent advances in allergen characterization and increased awareness of selected allergens, treatment of occupational allergies can be improved. Better information and improved cooperation between dental workers and their clinicians is needed.

Latex allergy: diagnosis and management

Latex allergy is an IgE-mediated immediate hypersensitivity response to natural rubber latex (NRL) protein with a variety of clinical signs ranging from contact urticaria, angioedema, asthma, and anaphylaxis. Major allergens include dipped latex products such as gloves and balloons. In highest risk for NRL allergy are patients with spina bifida, but health care workers and others who wear latex gloves are also at risk. NRL allergic patients may also react to fruits/foods, especially banana, kiwi, and avocado. Diagnosis is made by a positive latex RAST and/or skin prick test or challenge test to NRL. Allergen avoidance and substitution and the use of latex-safe devices including synthetic gloves (vinyl, synthetic polyisoprene, neoprene, nitrile, block polymers, or polyurethane) are essential for the affected patient. Accommodation in the workplace may include the use of powder-free, low-allergen NRL gloves or synthetic gloves. These preventive measures have significantly reduced the prevalence of reported reactions to NRL. Hyposensitization is not yet feasible.

Occupational allergies caused by latex

Allergy to natural rubber latex is an important cause of occupational allergy in healthcare workers. Disposable medical gloves are the major reservoir of latex allergens, particularly powdered gloves, in healthcare delivery settings. Diagnosis of latex allergy requires a history of exacerbation of cutaneous, respiratory, ocular, or systemic signs and symptoms after exposure to natural rubber latex products; and evidence of sensitization by patch testing, skin testing, measurement of latex-specific IgE antibodies, or challenge testing. Optimal management of latex allergy involves education concerning cross-reacting allergens, reduction of cutaneous or mucosal contact with dipped rubber products, and minimization of exposure to latex aeroallergens in work environments.

Recent developments in latex allergy

PURPOSE OF REVIEW

Immediate allergic reactions to natural rubber latex continue to be an important medical and occupational health problem. In this review we focus on progress made in understanding the significance of occupational exposure and epidemiology, risk groups, diagnosis and prevention of natural rubber latex allergy. We also discuss methods aimed at quantification of clinically relevant natural rubber latex allergens and studies on B-cell epitopes of major natural rubber latex allergens.

RECENT FINDINGS

Prospective studies have been published focusing on the prevention of natural rubber latex allergy. Efforts to identify and characterize new natural rubber latex allergens were continued in several research groups. The use of purified allergens or proteins produced by recombinant DNA technology was assessed in studies aimed at improving the diagnosis of natural rubber latex allergy as well as in developing quantitative methods for the measurement of specific natural rubber latex allergens. For the first time, conformational immunoglobulin E epitopes were identified in a major natural rubber latex allergen, hevein, using a novel chimera-based allergen epitope mapping strategy.

SUMMARY

Measures taken in health care to reduce exposure to natural rubber latex products seem to be effective in reducing the number of new sensitizations. A few new minor natural rubber latex allergens, probably important in allergen cross reactions, were identified, and some nonmedical natural rubber latex products were found to be potentially dangerous to natural rubber latex-allergic patients. Sensitive and specific immunoassays for quantification of clinically relevant natural rubber latex allergens in manufactured products were developed in some laboratories. These assays may eventually replace the nonspecific total protein measurement, currently advocated by health authorities in the indirect estimation of allergen amounts in natural rubber latex products. Knowledge about conformational immunoglobulin-binding B-cell epitopes of major allergens is expected to be helpful in designing optimal reagents to specific immunotherapy.

Latex sensitization in dental students using powder-free gloves low in latex protein:a cross-sectional study

In Germany, employers must provide low-protein, powder-free gloves. This study was carried out to determine the current prevalence of latex sensitization in dental students using these gloves and to compare our results with a study of the same design dating from 1990/1991 at our university. A cross-sectional study was performed by questionnaire, prick testing and determination of specific IgE antibodies. 226 of 403 dental students underwent prick testing with a panel of 8 aero-allergens, 1 commercially available latex extract and 5 high-ammonia accelerator-free latex fluids. 39 of 226 dental students (17.3%) had a positive prick test response to at least 1 of the 6 latex substances tested. The prick test positivity was similar in preclinical education (semester 1-6) and in clinical education (semester 7-10), at 17.1% and 17.4%, respectively. In 9 of 32 persons with positive prick tests, specific IgE antibodies to latex could be detected. Within the past 10 years, prick test positivity increased from 8.7% to 17.3%. 14 students (6.2%) reported a history of glove intolerance, 3 of them (1.3%) showing a positive prick test to latex. By the use of low-protein, powder-free gloves less students with glove intolerance were observed. The observed reactions to between 1 and 3 of 6 latex substances tested may indicate a decrease in intensity and spectrum of sensitization. Additionally non-occupational sensitization may be of importance.