Patients with allergic and irritant contact dermatitis are characterized by striking change of iron and oxidized glutathione status in nonlesional area of the skin.

To assess the consequences of oxidative stress in allergic and irritant contact dermatitis, we compared the iron level, unsaturated iron-binding capacity, total iron binding capacity, the percentage saturation of iron-binding capacity, the amount of diene conjugates as well as the amounts of total glutathione, reduced glutathione, oxidized glutathione, and the oxidized glutathione/reduced glutathione ratio in skin homogenate from lesional and nonlesional skin. Lesional skin samples were obtained from positive patch test sites to 5% NiSO4 in five subjects, and from chronic contact dermatitis lesions on the hands, which had exacerbated over 3--9 wk in six subjects. Contact dermatitis caused at least a 4-fold increase in the iron level in the lesional skin area compared with the nonlesional skin area (p < 0.02). The increase in the iron level depended on the duration of contact dermatitis and was accompanied by high unsaturated iron-binding capacity and total iron-binding capacity values in the positive patch test sites (p < 0.05), and by a high percentage saturation value in the chronic contact dermatitis lesions (p < 0.05). We found high indices for iron, total iron-binding capacity and diene conjugates in the apparently healthy skin of the patients with persistent contact dermatitis that significantly (p < 0.05) exceeded the corresponding values in the patients with only patch test reactions. In summary, we have succeeded in providing evidence that generalized oxidative damage of the skin occurs as a consequence of contact dermatitis in a restricted area.     

In vivo cytokine profiles in allergic and irritant contact dermatitis

Local cytokine profiles in skin biopsies from allergic and irritant patch test reactions were determined by in vivo immunohistochemistry to differentiate between these 2 clinically identical afflictions especially at the time of final reading in diagnostic patch testing. Biopsies were taken from established allergic persons after specific allergic patch test.-, to epoxy resin (1%) and formaldehyde (1%) and from non-allergic individuals with irritant patch tests to sodium lauryl sulfate (10%) and formaldehyde (8%). At 72 h after application of the agents, significantly enhanced frequencies of dermal infiltrating cells, producing IL-1α, TNF-α. IL-2. and IFN-γ per 100 infiltrating cells in the dermis. were observed in allergic as well us irritant patch test reactions, as compared to normal skin. Significantly higher frequencies of IL- Iα-producing cells were observed in biopsies from epoxy resin (1%) allergen-affected and sodium lauryl sulfate (10%) irritant-affected skin as compared to formaldehyde (1%) allergen-affected skin. In addition, significantly higher frequencies of TNF -α reproducing cells were observed in epoxy resin allergen-affected skin us compared to Formaldehyde (1%) allergen-affected and formaldehyde (8%) irritant affected skin. The allergic and irritant patch test reactions showed similar levels of expression of the Thl cytokines IL-2 and IFN-γ in the dermis. confirmed by probe based detection of IL-2 mRNA and IFN-γ- mRNA, In conclusion, the described similarity shows that allergens and irritants can induce the same profile of IL-la. TNF-α. IL-2. and IFN-γ production, resulting in the near impossibility of discriminating between allergic and irritant contact dermal is at the lime of patch test reading.     

Contact vitiligo following a strong patch test reaction to triglycidyl-p-aminophenol in an aircraft industry worker: case report and review of the literature

Epoxy resin systems (ERSs) are a frequent cause of occupational allergic contact dermatitis. A 50-year-old patient developed eczematous skin lesions on the back of his hands, lower arms and eye lids, 2 months after he had started working in aircraft construction. Patch tests showed positive reactions at day 3 to nickel sulfate, epoxy resin based on diglycidyl ether of bisphenol F (DGEBF) and 1,4-butanediol diglycidyl ether (1,4-BDDGE). The chemical triglycidyl-p-aminophenol (TGPAP) applied at 1% and 0.1% induced the strongest (+++ positive) reaction. About 4 months after the patch test with TGPAP, the patient presented with 2 circular depigmented spots in the former TGPAP-patch test areas. Dermatohistopathology confirmed the diagnosis of contact vitiligo.     

OCCUPATIONAL ALLERGIC CONTACT DERMATITIS CAUSED BY 2,4,6-TRIS-(DIMETHYLAMINOMETHYL)PHENOL, AND REVIEW OF SENSITIZING EPOXY RESIN HARDENERS

Background. Epoxy resin compounds (ERG) include a large number of sensitizing chemicals such as epoxy resins (ER), hardeners (curing agents), and reactive diluents. Allergic contact dermatitis (ACD) caused by ERCS is often occupational. Materials and Methods. We report a patient, sensitized to a hardener of a two-component epoxy paint. Three conventional patch test sessions were performed to diagnose the causative chemical. We also review the literature on sensitizing epoxy-resin hardeners. Results. A 47-year-old nonatopic woman developed dermatitis from a two-component epoxy paint. Patch testing with epoxy resin was negative, but 2,4,6–tris(dimethylaminomethyl)phenol (tris-DMP), used in the paint hardener, induced an allergic patch test reaction. We also review briefly other epoxy hardeners that have caused allergic dermatitis, including: (1) aliphatic polyamines, e.g., ethylenediamine, diethylenetriamine, triethylenetetramine, 3-dimethylaminopropylamine, and trimethylhexamethylenediamine; (2) cycloaliphatic polyamines, e.g., isophoronediamine and 3,3′-dimethyl-4,4-diaminodicyclohexylmethane; (3) aromatic amines, such as 4,4′-diaminodiphenylmethane, m-phenylene diamine, and 1,3-xylylene diamine; (4) dicyanodiamide; (5) triglycidyl isocyanurate, an epoxy compound that may be used as an epoxy-resin hardener; and (6) additives in epoxy accelerators, such as hexavalent chromate. Conclusions. No one chemical can be used to screen for sensitization to the many different epoxy hardeners. Extensive patch testing may be required to reveal the hardener that has caused the allergy. The hardener, 2,4,6-tris-dimethylaminomethyDphenol (tris-DMP), is a new sensitizer. To verify ACD caused by tris-DMP, patch-testing at 1% in petrolatum is suggested.     

Thermographic assessment of patch-test responses

Infra-red thermography was used to quantify, at patch test sites, the allergic responses to experimental preparations of nickel sulphate and primary irritant responses to sodium lauryl sulphate in small groups of volunteers. The technique was also used to assess the patch-test responses in a much larger group of patients who had undergone routine patch testing for contact allergy with a wide range of test substances and among which there were large numbers of allergic, irritant and equivocal reactions. Thermographically, when compared to the surrounding normal skin surface, the sites of allergic reactions appeared as hot areas, the temperature and area of which were apparently dependent on the severity of the response. For allergic responses, there was a good correlation between the clinical assessment and either of two thermographic parameters, temperature and area of involvement. Compared with an aqueous solution of nickel sulphate, 'poor' formulations of the allergen, such as a suspension in soft paraffin base, elicited smaller and cooler reactions. Irritant reaction sites were not 'hot' and the temperature at such sites was no different from that of the surrounding normal skin. Infra-red thermography is a convenient non-invasive technique which apparently can be used to discriminate between irritant and allergic responses and to quantify the latter type of response.     

A proposed relevance scoring system for positive allergic patch test reactions: practical implications and limitations

A relevance scoring system for positive allergic patch test reactions is proposed. It refers to current relevance (CR) as well as past relevance (PR), The system was evaluated in adult patients between January 1 and June 30, 1996, and limited to 4 allergens: nickel sulfate, neomycin sulfate, epoxy resin and colophony Certain methods available for increasing the accuracy of relevance were used in the present study. Practical implications and limitations of using a relevance scoring system are discussed.     

Occupational dermatoses from epoxy resin compounds

This study comprises 40 patients with skin disorders from current or previous occupational exposure to epoxy resin compounds (ERC) during 1984-1988. ERCs were the 3rd most common cause (32 of 264 cases: 12.1%) of currently relevant allergic contact dermatitis: 23 cases from epoxy resins based on the diglycidyl ether of bisphenol A (DGEBA-ERs), 5 from reactive diluents, 1 from amine hardeners (DETA), and 3 from epoxy acrylates. 2 cases (0.8%) of irritant contact dermatitis were due to ERCs. Methyl hexahydrophthalic anhydride (MHHPA, an epoxy hardener) caused 1 case of contact urticaria. Previously relevant occupational allergic contact dermatitis from DGEBA-ERs was detected in 5 cases. On patch testing, ERC allergens gave the following positive reactions: epoxy resin of the standard series in 35 cases (4.0% of 870 tested), epoxy reactive diluents in 10 (7.1% of 140), cycloaliphatic epoxy resins in 4 (11.1% of 36), epoxy acrylates in 4 (4.5% of 88), and amine compounds commonly used as epoxy hardeners in 17. Despite extensive patch test series, testing with patients' own ERCs remains important.     

Contact allergy to epoxy resin: risk occupations and consequences

Background. Epoxy resin monomers are strong skin sensitizers that are widely used in industrial sectors. In Denmark, the law stipulates that workers must undergo a course on safe handling of epoxy resins prior to occupational exposure, but the effectiveness of this initiative is largely unknown. Objectives. To evaluate the prevalence of contact allergy to epoxy resin monomer (diglycidyl ether of bisphenol A; MW 340) among patients with suspected contact dermatitis and relate this to occupation and work‐related consequences. Patients/methods. The dataset comprised 20 808 consecutive dermatitis patients patch tested during 2005–2009. All patients with an epoxy resin‐positive patch test were sent a questionnaire. Results. A positive patch test reaction to epoxy resin was found in 275 patients (1.3%), with a higher proportion in men (1.9%) than in women (1.0%). The prevalence of sensitization to epoxy resin remained stable over the study period. Of the patients with an epoxy resin‐positive patch test, 71% returned a questionnaire; 95 patients had worked with epoxy resin in the occupational setting, and, of these, one‐third did not use protective gloves and only 50.5% (48) had participated in an educational programme. Conclusion. The 1% prevalence of epoxy resin contact allergy is equivalent to reports from other countries. The high occurrence of epoxy resin exposure at work, and the limited use of protective measures, indicate that reinforcement of the law is required.     

Epoxy pipe relining - an emerging contact allergy risk for workers

Background. Epoxy pipe relining is a method of repairing old and worn water pipes supplying households. The method, using epoxy resin systems (ERSs), involves creating a new pipe inside an existing pipe. Large amounts of epoxy are normally handled at small, temporary worksites. Objectives. To describe working conditions and contact allergies to ERSs in 8 patients with occupational contact dermatitis related to their work in the relining trade. Methods. Eight patients with suspected work‐related eczema in the relining trade were referred to our Occupational and Environmental Dermatology outpatient unit. They were examined and patch‐tested between August 2010 and May 2011. Results. Seven patients were patch test‐positive to ERSs, and 6 of 8 reacted to the epoxy resin (MW 340) in the baseline series. Five of the patients were patch test‐positive to their own work products. Seven of the cases had to leave the relining trade because of skin problems. Conclusions. Relining is a widely used alternative to replacing old pipes, and entails a risk of massive skin exposure to ERSs and consequently a high risk of developing allergic contact dermatitis. Further mapping of working methods and use of personal protective equipment (PPE) is crucial to reduce hazardous skin exposure.     

Allergic contact dermatitis caused by epoxy resin systems in industrial painters

A group of industrial painters employed in 6 companies of the Norwegian oil industry was followed to assess the incidence of allergic contact dermatitis (ACD) caused by exposure to epoxy resin systems. The study lasted from 1 September 1997 to 31 August 2001 and included 2236 workers, contributing 5113 person years. Commercially available patch test series were supplemented with a special study series based on known or suspected sensitizers present at the workplaces. Of 57 patch-tested workers, 23 with ACD caused by epoxy resin systems were found, indicating an incidence rate of 4.5/1000 person years. In our study patch test series, 4 workers (17%) were identified solely by patch tests to 2,4,6-tris-(dimethylaminomethyl)phenol (tris-DMP), m-xylene-alpha,alpha-diamine (XAD), and/or 2,2,4 trimethylhexamethylenediamine. Positive patch tests to tris-DMP and XAD were seen in 7 and 8 workers, respectively, indicating that the 2 chemicals are important sensitizers in industrial painters. They are, however, not classified as skin sensitizers according to the European regulations on the classification and labelling of dangerous chemicals. The results show the usefulness of including patch tests based on an investigation of known and suspected skin sensitizers present at the workplaces.     

652例过敏性皮肤病斑贴试验变应原分析

目的:分析我院过敏性皮肤病患者常见的接触性变应原.方法:回顾性分析我院门诊652例行斑贴试验的过敏性皮肤病患者资料,包括接触性皮炎249例、面部皮炎158例、湿疹87例、激素依赖性皮炎64例、特应性皮炎51例、唇炎43例,并对斑贴试验结果及不同年龄、性别阳性率进行比较分析.结果:斑贴试验总阳性448例(68.71％)....     

Allergic contact dermatitis to epoxy resin in immersion oil for light microscopy

Allergic contact dermatitis caused by immersion oil used for microscopy is a recently recognized phenomenon. We report a case with characteristic findings of periorbital erythema and edema in a cytogenetics technician. Positive patch test responses to epoxy resin, epoxy acrylate, and the immersion oil were noted. This case represents yet another contact allergic reaction, possibly airborne, to epoxy resin present in immersion oil used for microscopy.     

Protective effect of barrier creams and spray coatings against epoxy resins

This study evaluates the protective capacity of 4 barrier creams and 2 methacrylate spray coatings against skin contact with epoxy resins. The effect of these materials on the strength and on the surface area of patch test reactions caused by epoxy resin was assessed in 11 volunteers with a known allergy to epoxy resins. Standard amounts of barrier cream and spray coating were applied on the skin. Then patch tests were carried out with epoxy resin on the pretreated sites. After 24 h patches were removed, 48 h thereafter the strength and surface area of the reactions were scored. Results were compared with the score of a control test. The use of 2 barrier creams resulted in a significant reduction of the surface area of the patch test reactions. Spray coatings significantly reduced both the strength and the surface area of the reactions. Our results suggest that methacrylate spray coatings and barrier creams may provide protection against epoxy resins during a test period of 24 h. However, the development of new formulations, adapted more specifically to this purpose, is necessary.     

Cross-reactivity among epoxy acrylates and bisphenol F epoxy resins in patients with bisphenol A epoxy resin sensitivity.

OBJECTIVE: The study's objective was 2-fold: first, to evaluate the potential cross-reactivity between Bis-A epoxy resins and epoxy acrylates and second, to study the cross reactivity between Bis-A epoxy resins and newer Bis-F epoxy resins in patients with allergic contact dermatitis to epoxy resins and had positive patch test to the standard epoxy resin based on bisphenol A. METHODS: Forty-one patients were patch tested to 23 chemicals including epoxy acrylates, Bis-A epoxy resins, and Bis-F epoxy resins, as well as reactive diluents and nonbisphenol epoxy resins. Questions concerning exposure to epoxy resins, occupational history, and problems with dental work were completed. RESULTS: All patients included in the study had positive reactions to the standard Bis-A epoxy resin. Twenty percent (8 of 41) of the patients reacted to at least one of the epoxy acrylates; the most common reaction was to Bis-GMA. Five of 8 patients who reacted to the epoxy acrylates had dental work, but only one patient had problems from her dental work. Six of 8 patients (75%) who reacted to epoxy resins and epoxy acrylates did not react to aliphatic acrylates. Thirty-two percent (13 of 41) reacted to tosylamide epoxy resin, and none reacted to triglycidyl isocyanurate resin. In addition, all patients (100%) had positive reactions to at least one of the Bis-F epoxy resins that were tested. CONCLUSIONS: Most patients with sensitivity to Bis-A epoxy resins do not cross-react with epoxy acrylates. Patients with positive patch test reactions to epoxy acrylates used in dentistry usually do not have symptoms from their dental work. To our knowledge, this is the largest series of patients with sensitivity to the standard Bis-A epoxy resin that have been patch tested with the more recently introduced Bis-F epoxy resins. There is significant cross-reactivity between Bis-A and Bis-F epoxy resins, which can be explained by their structural similarity.     

Occupational allergic contact dermatitis caused by epoxy diacrylate in ultraviolet-light-cured paint, and bisphenol A in dental composite resin

Allergic contact dermatitis (ACD) caused by epoxy di(meth)acrylates or bisphenol A is rare. Here 2 such cases are reported. A dental assistant had allergic contact dermatitis (ACD) caused by bisphenol A contained in denial composite resin (DCR) products based on epoxy dimethacrylate. The contact allergy was verified by allergic patch lest reactions to bisphenol A and 2 DCRs. The OCRs giving allergic reactions were analyzed, and 0.014–0.015% of bisphenol A was detected. Occupational ACD caused by bisphenol A in dental composite resins has not been described before. The other patient was a male process worker in a paint factory. He was sensitized by an epoxy diacrylate, 2.2-bis[4-(2-hydroxy-3-acryloxypropoxy)pheny]-propane (BIS-GA), and other acrylate compounds contained in raw materials of ultraviolet-light-curable paint. The epoxy diacrylate gave an allergic patch test reaction down to 0.016% in pet. He also had an allergic patch lest reaction to several other acrylate compounds. 2-hydroxypropyl acrylate, 2-hydroxypropyl acrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, diethyleneglycol diacrylate, triethylene glycol diacrylate, and tripropylene glycol diacrylate, indicating cross and/or concomitant sensitization.     

Interactions of sulfates of divalent metals in nickel-sulfate-sensitive patients

Abstract 70 nickel-sensitive subjects who previously gave positive patch test response lto 10 μl of nickel sulfate 0.1 M, were patch tested to 10 μl of mixed aqueous solutions containing nickel sulfate 0.1 M +magnesium sulfate 0.3 M, nickel sulfale 0.1 M+zinc sulfate, 0.3 and 0.5 M, respectively, nickel sulfate 0.1 M+ manganese sulphate 0.3 and 0.5 M, respectively nickel sulphate 0.1 M+ cadmium sulfate 0.1 and 0.3 M, respectively, nickel sulfate 0.1 M + iron sulfate (III) 0.1 and 0.3 M, respectively, and to 10 μl of aq. cadmium sulfate 0.1 M, aq. cadmium sulfate 0.3 M, aq. iron sulfate 0.1 M, aq. iron sulfate 0.3 M. The results showed that, whilst sulfates of divalent metals with similar size and redox properties (Mg, Zn and Mn) were able to reduce or to suppress, in a dose-dependent way, the majority (75%) of nickel reactions, those with large radius and different oxidation state(Fe III), generally gave an increase in the reactions. In about 15% of the tested subjects, an increase in all the positive reactions to the mixed solutions was found. The findings seem to demonstrate that in only a majority but not all of nickel sulfate allergic reactions, is Ni(II) able to substitute for divalent ions with similar properties at the ion sites of some proteins. This tendency reproduces the results of experimental systems, in which nickel toxicity and cancerogenity are considered responsible. In contrast, in about 15% of the tested subjects, there was a general enhancement of the reactions. In these cases, either the occurrence of a “hyper-irritable” skin caused by the adopted test system or, more likely, the formation of Ni complexes with different geometries, is hypothesized.     

Patch testing with nickel sulfate: comparison between 2 nickel sulfate preparations and 2 different test sites on the back

Among patients routinely undergoing patch testing for suspected allergic contact dermatitis (ACD), nickel is the most frequently sensitizing hapten, with a clear predominance in the female population. However, some patients who report the appearance of dermatitis upon exposure to metal objects show negative patch test results to a nickel sulfate 5% pet. application. In some cases, a positive response to nickel can be observed simply by repeating the patch test. The objective of our study was to assess if, during routine patch testing, positive responses to nickel sulfate are missed owing to contingent problems, referring to application site, patch test execution or variations in skin reactivity. To this end, we applied 2 different patch test materials containing nickel sulfate 5% pet. to 3040 consecutive patients, undergoing patch testing for suspected allergic contact dermatitis, during the same session. The rôle of the test site was also investigated by applying the preparation on 2 different sites of the back in 30 patients. Of the whole, 612 patients (20%) showed positive patch test responses. The 2 nickel materials were almost equivalent: 78% of nickel-sensitive patients had positive reactions to both, whereas 11% showed a positive response to 1 preparation alone. No variations in patch test responses in relation to application site were observed. Our data show that false-negative patch test responses to nickel are frequent. The use of 2 different preparations during the same patch test session increases the response rate by 10%.     

Contact allergy to epoxy (meth)acrylates

Background: Contact allergy to epoxy (meth)acrylates, 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy) phenyl]propane (bis-GMA), 2,2-bis[4-(2-hydroxy-3-acryloxypropoxy)phenyl]-propane (bis-GA), 2,2-bis[4-(methacryl-oxyethoxy)phenyl] propane (bis-EMA), 2,2-bis[4-(methacryloxy)phenyl]-propane (bis-MA), and glycidyl methacrylate (GMA) is often manifested together with contact allergy to diglycidyl ether of bisphenol A (DGEBA) epoxy resin.
Objective: To analyse patterns of concomitant allergic reactions to the five epoxy (meth)acrylates in relation to exposure.
Methods: We reviewed the 1994–2008 patch test files at the Finnish Institute of Occupational Health (FIOH) for reactions to the five epoxy (meth)acrylates, and examined the patients' medical records for exposure.
Results: Twenty-four patients had an allergic reaction to at least one of the studied epoxy (meth)acrylates, but specific exposure was found only in five patients: two bis-GMA allergies from dental products, two bis-GA allergies from UV-curable printing inks, and one bis-GA allergy from an anaerobic glue. Only 25% of the patients were negative to DGEBA epoxy resin.
Conclusions: The great majority of allergic patch test reactions to bis-GMA, bis-GA, GMA and bis-EMA were not associated with specific exposure, and cross-allergy to DGEBA epoxy resin remained a probable explanation. However, independent reactions to bis-GA indicated specific exposure. Anaerobic sealants may induce sensitization not only to aliphatic (meth)acrylates but also to aromatic bis-GA.     

Increased sensitivity of patch testing by standardized tape stripping beforehand: a multicentre diagnostic accuracy study

Background: As a modification of patch testing, the strip patch test was established to obtain more sensitive and reliable test results. Comparative data on diagnostic accuracy for both tests are missing. Objectives: To compare the diagnostic accuracy of strip patch tests and patch tests in detecting sensitizations in patients with suspected allergic contact dermatitis by using patient history as the reference standard. Patients/methods: In a multicentre, prospective, investigator‐blinded study 790 patients were enrolled. The defined reference standard was established prior to patch testing. Patch tests were performed with nickel sulfate, potassium dichromate, and lanolin alcohol. Duplicate tests were simultaneously performed on both sides of the back, of which one randomly chosen side was tape stripped beforehand, according to a standardized procedure. Primary outcome was the difference in sensitivity between strip patch test and patch test. Results: Seven hundred and eighty‐seven patients were included in the analysis. Strip patch tests detected considerably more sensitization to nickel sulfate and potassium dichromate than patch tests: differences of sensitivities were 16.4% (95% CI, 8.7–24.1%) for nickel sulfate and 25.0% (95% CI, 8.9–41.0%) for potassium dichromate, both favouring the strip patch test. Conclusions: The standardized strip patch test proved to be accurate and clinically safe and is promising to improve diagnosis of allergic contact dermatitis beyond the patch test.     

Allergic contact dermatitis in patients with frontal fibrosing alopecia: An international multi‐center study

Frontal fibrosing alopecia (FFA) mainly affects the anterior hairline and eyebrows and its etiology and associated factors remain obscure. The aim of this study was to evaluate the allergic contact dermatitis with patch test in patients with FFA. In this prospective study, 20 patients with FFA and 24 age and sex‐matched healthy individuals were evaluated with patch testing. Diagnosis was made histologically, clinically and based on dermoscopic findings. Demographic data, age of onset, disease duration and FFA severity index are evaluated in all patients. Positive patch test reaction to one or more allergen was observed in 65% of patients while it was 37.5% in control group (P = .003). There was a significant difference between age (P = .006) and positive patch test results. No statistical significant difference was observed in the results of patch testing and disease duration (P = .519), menopausal status (P = .085), and FFA severity index (P = .573). Our findings suggest an association between FFA and allergic contact dermatitis. The utility of patch testing in FFA patients can explore the role of allergic etiology and may have an enormous impact on the diagnostic potential and quality of life of these patients.