High prevalence of contact allergy in adolescence: results from the population-based BAMSE birth cohort

Subclinical immune responses to nickel in sensitized individuals-a dose-response study

BACKGROUND

Nickel is the leading cause of contact allergy in Europe, with 14.5% of the adult population being sensitized. Despite regulations limiting nickel release from consumer items, the incidence and prevalence of nickel allergy remain high.

OBJECTIVE

To investigate the clinical and subclinical immune response to low-dose nickel exposure on nickel pre-exposed skin to assess the adequacy of current regulatory limits.

METHOD

Nickel-allergic and healthy controls were patch tested with nickel twice with a 3-4 weeks interval. The first exposure used the diagnostic concentration of 2000 μg/cm2 nickel sulphate, and the same skin areas were then re-exposed to 0.2, 0.5, 12.8 and 370 μg/cm2 nickel sulphate. After 48 h, the patch reactions were examined for clinical signs of eczema, and skin biopsies were collected. The transcriptomic immune profile was analysed with Nanostring nCounter and quantitative polymerase chain reaction.

RESULTS

Two nickel-allergic participants (15%) had clinical reactions to the regulatory limiting doses for nickel (0.2/0.5 μg/cm2) following re-exposure. There was immune activation in all skin areas following re-exposure to nickel, predominantly mediated by up-regulation of cytokines and chemokines. In all nickel re-exposed skin areas, 81 genes were up-regulated independent from the clinical response. In skin areas exposed to 0.2 μg/cm2, 101 immune-related genes were differentially expressed, even when no clinical response was observed. Healthy controls showed up-regulation of three genes in response to nickel re-exposures without any clinical reactions.

CONCLUSION

Immune activation can be induced in skin with local memory to nickel upon challenge with nickel doses within the regulatory limits. Our findings suggest that the regulatory limits in the European nickel regulation may not provide sufficient protection for consumers against low-dose exposures.

Probing the effectiveness of barrier creams against human skin penetration of nickel powder

OBJECTIVE

Barrier creams (BCs) are marketed as locally applied medical devices or cosmetic products to protect the skin from exposure to chemicals and irritants. Generally, the mechanism of action of such products is mainly due to the formation of a superficial thin film between the skin and the irritant or sensitizer, thus reducing or totally blocking the cutaneous penetration of such agents. Specifically, studies focusing on the effectiveness of commercial protective creams to prevent nickel cutaneous penetration are extremely scarce. The aim of the current work, therefore, is to evaluate the protective role of a commercially available barrier cream for nickel and compare the results with a simple moisturizing, following exposure to Ni powder.

METHODS

Marketed BCs were evaluated and tested. Human skin absorption of Ni was studied in vitro using static Franz diffusion cells.

RESULTS

Our results demonstrate that the application of both formulations caused a reduction of Ni inside the skin (8.00 ± 3.35 μg cm-2 for the barrier cream and 22.6 ± 12.6 μg cm-2 for the general moisturizing product), with the specialized barrier cream being statistically (p = 0.015) more efficient on forming a protective barrier, thus evidencing the importance of some ingredients in such formulations on the nickel dermal accumulation.

CONCLUSIONS

The composition of the formulations based on film-forming or chelating agents may play an imperative role in reducing the cutaneous penetration of Ni.

Colophonium-related Allergic Contact Dermatitis Caused by Medical Adhesive Tape Used to Prevent Skin Lesions in Soldiers

Medical adhesive tapes are commonly recommended for the prevention of friction blisters during hiking and military marches. The aim of this paper is to report on the results of investigations into an outbreak of tape-related foot dermatitis in 26 military conscripts following continuous use of medical adhesive tapes for several days during a field exercise. Patch tests were performed using baseline series and aimed testing was performed with colophonium-related substances and different medical adhesive tapes. Contact allergy to the adhesive tapes used was found in 20 (77%) subjects, and contact allergy to colophonium in 16 (61%). Chemical analysis detected colophonium-related substances in the culprit tapes. Compared with consecutive dermatitis patients investigated at our Department of Occupational and Environmental Dermatology in the previous 10 years, conscripts with colophonium allergy had increased odds ratios for concomitant contact allergy to phenol formaldehyde resins and fragrance substances including hydroperoxides of limonene and linalool. The results show that prolonged use of medical adhesive tapes on intact skin carries a high risk for allergic contact dermatitis. Prior to their introduction on the market, medical devices should be assessed for possible side-effects.

Fragrance allergens in cosmetic products marketed for children in Denmark

BACKGROUND

Fragrances are among the most common contact allergens in children. Cosmetic products are the most frequent source of skin exposure.

OBJECTIVE

To investigate exposure to fragrance allergens among Danish children, based on a sample of 1179 cosmetic products marketed for children.

METHODS

Information regarding cosmetic products marketed to children was obtained using a non-profit smartphone application registry, with data from December 2015 to November 2022.

RESULTS

The number of validated products was 26  537, of which 1349 marketed for children. After elimination of duplicates, 1179 (4.4%) individual products remained. The majority 53.8% (634/1179) of the products were fragranced. The highest frequency of declared fragrances was found in 'Facial care'-products: 93.0% (80/86), of which 97.7% were lip balms. The highest number of labelled fragrances in one single product (n = 16) was found in a baby perfume. Fragrance mix I (FMI) or II (FMII) allergens were found in 25.3% (298/1179) of the products. Limonene and linalool were the two most frequently labelled fragrance allergens.

CONCLUSION

Children can be exposed to a vast number of fragrance allergens from scented cosmetic products. Allergens from FM I and FMII are widely used in cosmetic products marketed to children. Patch testing with FMI and FMII remains relevant in children.

Postoperative Excessive Bleeding following Stainless-Steel Crown Placement in Healthy Children with a Suggested Approach for Prevention

Stainless-Steel Crown (SSC) placement is a common treatment in children, usually without significant adverse consequences. The present case series reports six healthy children were admitted to emergency rooms in two medical centers with delayed excessive bleeding from their gingiva, adjacent to newly placed SSCs. The bleeding, in some cases, was so extensive, that it induced vomiting and anxiety, among the children and their parents, and in two cases required surgical suturing. In all six cases, the most probable etiology was a toxic reaction to the released nickel or chromium ions from the SSCs, exacerbated by contact with wounded and bleeding gingiva. Expression of this cytotoxic mode of action, due to metal ions released from SSCs, is not well documented in children. Our aims are to raise awareness of this unique complication and to suggest an approach to minimize and prevent its occurrence. Recommended immediate treatment includes frequent rinsing of the gingiva to wash out released metal ions and decrease their toxic effect. Furthermore, in the following appointments, we recommend using only SSCs previously soaked in water for several weeks, using zirconia crowns, or using Hall's technique when appropriate.

Immunological Mechanisms of Metal Allergies and the Nickel-Specific TCR-pMHC Interface

Besides having physiological functions and general toxic effects, many metal ions can cause allergic reactions in humans. We here review the immune events involved in the mediation of metal allergies. We focus on nickel (Ni), cobalt (Co) and palladium (Pd), because these allergens are among the most prevalent sensitizers (Ni, Co) and immediate neighbors in the periodic table of the chemical elements. Co-sensitization between Ni and the other two metals is frequent while the knowledge on a possible immunological cross-reactivity using in vivo and in vitro approaches remains limited. At the center of an allergic reaction lies the capability of a metal allergen to form T cell epitopes that are recognized by specific T cell receptors (TCR). Technological advances such as activation-induced marker assays and TCR high-throughput sequencing recently provided new insights into the interaction of Ni2+ with the αβ TCR-peptide-major histocompatibility complex (pMHC) interface. Ni2+ functionally binds to the TCR gene segment TRAV9-2 or a histidine in the complementarity determining region 3 (CDR3), the main antigen binding region. Thus, we overview known, newly identified and hypothesized mechanisms of metal-specific T cell activation and discuss current knowledge on cross-reactivity.

Skin permeation of nickel, cobalt and chromium salts in ex vivo human skin, visualized using mass spectrometry imaging

Skin permeation and distribution of three of the most common skin sensitizers was investigated using a previously developed animal-free exposure method combined with imaging mass spectrometry. Nickel, cobalt, and chromium (III) salts were dissolved in a buffer and exposed to human skin ex vivo, to be analyzed using time of flight secondary ion mass spectrometry (ToF-SIMS). Our findings demonstrate that metal haptens mainly accumulated in the stratum corneum, however all three metal sensitizers could also be detected in the epidermis. Cobalt and chromium (III) species penetrated into the epidermis to a larger extent than nickel species. The degree of penetration into the epidermis is suggested to be affected by the sensitization potency of the metal salts, as well as their speciation, i.e. the amount of the respective metal present in the solution as bioaccessible and solubilised ions. Our method provided permeation profiles in human skin for known sensitizers, on a level of detail that is not possible to achieve by other means. The findings show that the permeation profiles are different, despite these sensitizers being all metal ions and common causes of contact allergy. Studying skin uptake by only considering penetration through the skin might therefore not give accurate results.

Prevalence of contact allergies in the population compared to a tertiary referral patch test clinic in Jena/Germany

BACKGROUND

The contact allergy prevalences in patch-tested patients are usually higher than those in the population, owing to morbidity-driven selection.

OBJECTIVES

To examine the differences between two samples, one from the population, one from the patch test clinic, in one area of Germany (Jena, Thuringia).

METHODS

Between August 2008 and October 2011, a total of 519 participants of the population-based european dermato-epidemiology network (EDEN) fragrance study were patch tested in Jena using a TRUE Test baseline series extended with some pet.-based (fragrance) allergen preparations. Between 2007 and 2012 (inclusive), 1906 routine patients were patch tested for suspected allergic contact dermatitis (ACD) in the Jena University Hospital Department; of these 1694 (83.2%) with the German baseline series using pet./aq.-based, investigator-loaded allergens.

RESULTS

In the population (clinical) sample, 19.6% (41.1%) were sensitized to at least one of the allergens considered. The most common baseline series allergens in the population/clinical sample were nickel (10.5%/13.2%), fragrance mix (FM) II (2.9%/6.7%), FM I (2.3%/8.3%), and cobalt (1.6%/5%). The clinical sample was slightly older (71.5% vs 55.9% age 40+) and included less males (36% vs 49.3%).

CONCLUSIONS

Results are quite similar, although prevalences are usually higher in the clinical setting, with the exception of p-tert-butylphenol formaldehyde resin.

Nickel Hypersensitivity to Atrial Septal Occluders: Smoke Without Fire?

Nickel is one of the most common contact allergens worldwide; it is used as the main component of the devices used for atrial septal defects (ASDs) and patent foramen ovale (PFO) closure. Developing nickel hypersensitivity after PFO/ASD occlusion is significantly rarer described in medical literature than typical nickel contact sensitization. The exact pathophysiological mechanism of this "device syndrome" remains unknown, and many question the real incidence or even the existence of this clinical entity. Nevertheless, it has been associated with a wide spectrum of symptoms, including chest pain, migraines, palpitation, and dyspnea. Skin patch tests are the first-line approach to diagnose nickel hypersensitivity. However, diagnostic criteria for the device syndrome have not been developed, and diagnosis in reported cases is established by a process of elimination. Management-drug therapy (corticosteroids, clopidogrel, etc.) or even surgical explantation in severe cases-of patients developing such clinical manifestations after percutaneous PFO/ASD occlusion is empirical. Undoubtedly, endocardiac device-related nickel hypersensitivity requires more focused research to discover the underlying mechanism as well as to develop reliable prognostic tests for detecting high-risk patients and preventing severe nickel hypersensitivity reactions.

Integrative transcriptome analysis deciphers mechanisms of nickel contact dermatitis

Background

Nickel‐induced allergic contact dermatitis (nACD) remains a major occupational skin disorder, significantly impacting the quality of life of suffering patients. Complex cellular compositional changes and associated immunological pathways are partly resolved in humans; thus, the impact of nACD on human skin needs to be further elucidated.

Methods

To decipher involved immunological players and pathways, human skin biopsies were taken at 0, 2, 48, and 96 hours after nickel patch test in six nickel‐allergic patients. Gene expression profiles were analyzed via microarray.

Results

Leukocyte deconvolution of nACD‐affected skin identified major leukocyte compositional changes at 48 and 96 hours, including natural killer (NK) cells, macrophage polarization, and T‐cell immunity. Gene set enrichment analysis mirrored cellular‐linked functional pathways enriched over time. NK cell infiltration and cytotoxic pathways were uniquely found in nACD‐affected skin compared to sodium lauryl sulfate–induced irritant skin reactions.

Conclusion

These results highlight key immunological leukocyte subsets as well as associated pathways in nACD, providing insights into pathophysiology with the potential to unravel novel therapeutic targets.

Suitable test concentration of cobalt and concomitant reactivity to nickel and chromium: A multicentre study from the Swedish Contact Dermatitis Research Group

BACKGROUND

In Sweden, cobalt chloride 0.5% has been included in the baseline series since the mid-1980s. A recent study from Stockholm showed that cobalt chloride 1% petrolatum (pet.) was more suitable than 0.5%. Cobalt chloride at 1.0% has been patch tested for decades in many European countries and around the world.

OBJECTIVES

To study the suitability of patch testing to cobalt 1.0% vs 0.5% and to analyze the co-occurrence of allergy to cobalt, chromium, and nickel.

RESULTS

Contact allergy to cobalt was shown in 90 patients (6.6%). Eighty (5.9%) patients tested positive to cobalt 1.0%. Thirty-seven of the 90 patients (41.1%) with cobalt allergy were missed by cobalt 0.5% and 10 (0.7%) were missed by cobalt 1.0% (P < .001). No case of patch test sensitization was reported. Allergy to chromium was seen in 2.6% and allergy to nickel in 13.3%. Solitary allergy to cobalt without nickel allergy was shown in 61.1% of cobalt-positive individuals. Female patients had larger proportions of positive reactions to cobalt (P = .036) and nickel (P < .001) than males.

CONCLUSION

The results speak in favor of replacing cobalt chloride 0.5% with cobalt chloride 1.0% pet. in the Swedish baseline series, which will be done 2021.

Potential Co-Factors of an Intraoral Contact Allergy-A Cross-Sectional Study

The aim of this cross-sectional study was to evaluate the frequency of dental allergens and potential co-factors, especially hypothyroidism, for patients with an intraoral contact allergy. From 2015 to 2016, patients with confirmed symptoms of an intraoral contact allergy (study group SG n = 50) were recruited in the dental clinic of the University of Leipzig. The participants of the control group (CG n = 103) were patients without oral diseases or intraoral symptoms of a contact allergy. For the data collection, a new "Allergy questionnaire" was developed. Information on allergies and general diseases were collected. The statistical analysis was carried out with SPSS 23.0. Sensitizations/allergies to metals and composites were higher in SG compared to CG. Of all study participants (n = 148), 14.2% (n = 21) had a nickel allergy. In 18% (n = 8) of the SG a cobalt allergy based on all metal allergens could be seen. In addition, an association between a nickel and cobalt allergy was found. Hypothyroidism occurred significantly more frequently (p = 0.049) in SG than in CG. Sensitizations and allergies can occur to metals in dental alloys. Hypothyroidism increased the risk of having an allergy threefold.

Nickel allergy is associated with wheezing and asthma in a cohort of young German adults: results from the SOLAR study

Background

Nickel allergy is the most prevalent contact allergy. It belongs to a different hypersensitivity type to asthma and rhinoconjunctivitis. The aim of this analysis was to assess whether self-reported nickel allergy is associated with incident wheezing, asthma and rhinoconjunctivitis in young German adults, taking into account potential effect modification by sex.

Methods

In total, 2051 (70.6%) participants aged 19–24 years took part in the second phase of SOLAR (Study on Occupational Allergy Risks), a follow-up study of ISAAC II (the second phase of the International Study of Asthma and Allergies in Childhood) in Germany. Self-reported nickel allergy, as well as having pierced ears, and the three outcomes incident wheezing, asthma and rhinoconjunctivitis, were analysed stratified for sex. Logistic regression adjusted for potential confounders was performed.

Results

An association between self-reported nickel allergy and incident wheezing was observed for men and women, while only in males did pierced ears show a significant association with the outcome (adjusted OR 2.26, 95% CI 1.10–4.62). Also only in males, self-reported nickel allergy was associated with elevated odds for incident asthma (adjusted OR 4.34, 95% CI 1.22–15.41). Neither in men nor in women was a significant association observed for incident rhinoconjunctivitis.

Conclusion

Our results suggest that self-reported nickel allergy is associated with incident wheezing. Whether this association is due to environmental or genetic predisposition, or due to an overlap of the mechanisms of type I and type IV hypersensitivity, needs to be elucidated.

Self-reported nickel allergy is associated with incident wheezing in young German males and females, and with incident asthma in males, whereas no significant association was observed for self-reported nickel allergy and incident rhinoconjunctivitishttp://bit.ly/2YHmwBA

Impact of Heavy Metals on Host Cells: Special Focus on Nickel-Mediated Pathologies and Novel Interventional Approaches

BACKGROUND

Heavy metals [arsenic, aluminium, cadmium, chromium, cobalt, lead, nickel (Ni), palladium and titanium] are environmental contaminants able to impact with host human cells, thus, leading to severe damage.

OBJECTIVE

In this review, the detrimental effects of several heavy metals on human organs will be discussed and special emphasis will be placed on Ni. In particular, Ni is able to interact with Toll-like receptor-4 on immune and non-immune cells, thus, triggering the cascade of pro-inflammatory cytokines. Then, inflammatory and allergic reactions mediated by Ni will be illustrated within different organs, even including the central nervous system, airways and the gastrointestinal system.

DISCUSSION

Different therapeutic strategies have been adopted to mitigate Ni-induced inflammatoryallergic reactions. In this context, the ability of polyphenols to counteract the inflammatory pathway induced by Ni on peripheral blood leukocytes from Ni-sensitized patients will be outlined. In particular, polyphenols are able to decrease serum levels of interleukin (IL)-17, while increasing levels of IL- 10. These data suggest that the equilibrium between T regulatory cells and T helper 17 cells is recovered with IL-10 acting as an anti-inflammatory cytokine. In the same context, polyphenols reduced elevated serum levels of nitric oxide, thus, expressing their anti-oxidant potential. Finally, the carcinogenic potential of heavy metals, even including Ni, will be highlighted.

CONCLUSION

Heavy metals, particularly Ni, are spread in the environment. Nutritional approaches seem to represent a novel option in the treatment of Ni-induced damage and, among them, polyphenols should be taken into consideration for their anti-oxidant and anti-inflammatory activities.

Contamination of skin and surfaces by cobalt in the hard metal industry

BACKGROUND

It is well known that hard metal workers have historically been affected by contact allergy to cobalt. Knowledge is sparse about occupational skin exposure to cobalt, in terms of skin doses and sources of exposure, which could be used to improve protection of workers.

OBJECTIVES

To improve knowledge about skin doses and sources of skin exposure to cobalt within hard metal production, thereby facilitating better protection of workers.

METHODS

Forty workers were sampled on the index finger by acid wipe sampling after 2 hours of work. The samples were analysed with inductively coupled plasma mass spectrometry. Cobalt spot testing was performed in the work environment.

RESULTS

The highest skin doses were found among raw material workers. Skin doses among other production workers were also significant. Most office workers had low, but measurable, levels of cobalt on the skin. Glove use varied between workers. Cobalt was found on production equipment, on items in the canteen area, and on handles and buttons throughout the company.

CONCLUSIONS

Cobalt skin doses were prominent, and originated from contact with raw materials, sintered materials, and contaminated surfaces. Cobalt was present on surfaces outside production areas. Companies need to identify and reduce skin exposure for protection of workers.

Contact Allergy: A Review of Current Problems from a Clinical Perspective

Contact allergy is common, affecting 27% of the general population in Europe. Original publications, including case reports, published since 2016 (inclusive) were identified with the aim of collating a full review of current problems in the field. To this end, a literature search employing methods of systematic reviewing was performed in the Medline^® and Web of Science™ databases on 28 January 2018, using the search terms (“contact sensitization” or “contact allergy”). Of 446 non-duplicate publications identified by above search, 147 were excluded based on scrutiny of title, abstract and key words. Of the remaining 299 examined in full text, 291 were deemed appropriate for inclusion, and main findings were summarised in topic sections. In conclusion, diverse sources of exposures to chemicals of widely-differing types and structures, continue to induce sensitisation in man and may result in allergic contact dermatitis. Many of the chemicals are “evergreen” but others are “newcomers”. Vigilance and proper investigation (patch testing) are required to detect and inform of the presence of these haptens to which our populations remain exposed.

Imaging mass spectrometry for novel insights into contact allergy - a proof-of-concept study on nickel

BACKGROUND

In spite of extensive regulation to limit exposure, nickel remains the main cause of contact allergy in the general population. More detailed knowledge on the skin uptake of haptens is required. So far, no method exists for the visualization of this clinically relevant hapten and its distribution in the skin.

OBJECTIVES

To show, in terms of a proof of concept, that imaging mass spectrometry [time of flight secondary ion mass spectrometry (ToF-SIMS)] can be applied for investigation of the penetration and distribution of nickel in human skin.

METHOD

Full-thickness human skin obtained from breast reduction surgery was exposed to nickel sulfate (5% in deionized water) for 24 h in Franz-type diffusion cells. Biopsies were obtained from nickel-treated samples and control (deionized water). The tissue was sliced, and analysed with ToF-SIMS, generating high-resolution images of ion distribution in the epidermis and upper dermis.

RESULTS

The skin layers could be discerned from the ToF-SIMS data, particularly on the basis of the collagen signal. Nickel ions were localized to the stratum corneum and upper epidermis.

CONCLUSIONS

This is the first time that ToF-SIMS has been applied to trace the distribution of a hapten in human skin. Proof of principle was shown for nickel, and the technique can, in the future, be expanded for investigation of the skin distribution of clinically relevant sensitizers in general.

Low patch test reactivity to nickel in unselected adolescents tested repeatedly with nickel in infancy

BACKGROUND

It is questionable how repeated patch tests with nickel sulfate in infancy affect nickel patch test reactivity at a later age.

METHODS

The Danish Allergy Research Center (DARC) cohort encompasses 562 infants invited to a clinical examination including patch tests with nickel sulfate six times during the first 36 months of life. At the follow-up investigation at 14 years of age (2013-2014), participants were offered re-patch tests with nickel sulfate. The Odense Adolescence Cohort Study TOACS cohort encompasses 1501 schoolchildren evaluated for the first time at 14 years of age (1995-1996) including clinical examination and nickel sulfate patch tests. The prevalence of nickel sensitization in the DARC cohort was compared to the prevalence in the TOACS cohort at 14 years of age.

RESULTS

Nickel sulfate sensitization was found in 1.2% of the participants from the DARC cohort tested repeatedly with nickel sulfate in early childhood and retested at 14 years of age compared to 8.6% of the participants from the TOACS cohort patch-tested for the first time at 14 years of age using the same patch test system and test concentration.

CONCLUSION

The significant difference in nickel patch test reactivity comparing the two cohorts may reflect an immunologic effect or the effect of nickel regulation.