Oral lichenoid lesions in two snuff users with contact allergy to carvone.

BACKGROUND: Contact allergy to the mint-tasting flavour carvone has been observed in patients with oral lichenoid lesions (OLL). Mint-flavoured products such as toothpaste frequently contain carvone. Snuff is a smokeless tobacco product that is chewed or placed in the mouth rather than smoked. In Sweden, the use of snuff and its flavoured versions is extremely common. OBJECTIVES: To investigate whether the consumption of mint-flavoured snuff is associated with contact allergy to carvone and subsequently plays a role in the aetiology of OLL. METHODS: Regarding the two patients, patch testing with snuff pouches was performed. High-performance liquid chromatography and gas chromatography-mass spectrometry analysis were used for identification of carvone in different snuff samples. RESULTS: Two patients with OLL were contacted allergic to carvone when patch tested. Both were using mint-flavoured snuffs several hours a day for many years. One patient was contacted allergic to the snuff pouch tested as is. Carvone was detected in the snuff samples of both patients. CONCLUSIONS: The patients were recommended to avoid the use of mint-flavoured snuffs, toothpaste and foodstuffs. At follow-up 3 months later, the patients had a dramatic clinical improvement of the OLL and oral symptoms. Exposure to mint-flavoured snuffs can be overlooked as a possible aggravating/provoking factor in OLL.

Increased Rates of Gold and Acrylate Allergy in Individuals with Fibromyalgia Tested with an Extended Dental Patch Test Series.

Fibromyalgia is a common chronic pain condition. Rates of contact allergy in individuals with fibromyalgia have not been widely studied. Systemic contact allergy can present with muscle and joint pain and general malaise. The aim of this study is to investigate contact allergy rates in individuals with fibromyalgia to the sensitizers in an extended dental series and compare with control groups. Contact allergy to gold was significantly more common in the fibromyalgia group than the dermatitis control group. When corrected for patch test system, contact allergy to gold was significantly more common in the fibromyalgia group than the dental control group. Contact allergy to hydroxyethyl methacrylate and grouped acrylates and methacrylates was significantly more common in the fibromyalgia group than the dental control group. In conclusion, individuals with fibromyalgia may have a propensity to sensitization to gold, either via an increased exposure or an alteration in the oral environment. Gold is also implicated in systemic contact dermatitis and may be a factor in elicitation of symptoms in individuals with fibromyalgia. Acrylate allergy is also common in the fibromyalgia population and may be a consequence of occupational exposure or dental treatment.

Epoxy allergy, investigation of a modern industry.

BACKGROUND: Five workers from an industry manufacturing various articles from carbon fibre reinforced epoxy plastics were referred to our department because of suspected occupational allergic contact dermatitis (OACD). When patch tested, four of them had positive reactions to components of epoxy resin systems (ERSs) that could explain their current skin problems. All of them had been working at the same workstation at a specially designed pressing machine, with operations including manually mixing epoxy resin with hardener. Multiple cases of OACD in the plant prompted an investigation including all workers with possible risk exposures at the plant. OBJECTIVES: To investigate the prevalence of occupational dermatoses and contact allergies among the workers at the plant. MATERIALS AND METHODS: Totally 25 workers underwent investigation that included a brief consultation with a standardized anamnesis and clinical examination followed by patch testing. RESULTS: ERSs-related reactions were found in 7 of the 25 investigated workers. None of the seven had a history of previous exposure to ERSs and they are regarded as sensitized through work. CONCLUSIONS: Twenty-eight percent of investigated workers showed reactions to ERSs. Of these the majority would have been missed if supplementary testing would not have been added to testing with the Swedish base line series.

Use test with l-carvone in toothpaste on sensitized individuals.

BACKGROUND: The mint flavour carvone (l-carvone) is considered a weak contact allergen. However, contact allergy to carvone is more prevalent in patients with oral lichen planus or oral lichenoid lesions (OLP/OLL). OBJECTIVE: Our aim was to investigate how carvone affects sensitized individuals through a use test with toothpaste containing carvone. Non-flavoured toothpaste served as control. METHODS: Subjects were patch tested prior to the use test-14 subjects allergic to carvone (11 with OLP/OLL), 20 subjects with OLP/OLL and 3 healthy controls. The month-long use test comprised of using toothpaste twice daily. Subjects were examined fortnightly. Clinical signs were assessed with a mucosal scoring system. The subjects' oral health-related quality of life was measured with the oral health impact profile (OHIP-49). RESULTS: Local reactions to the carvone toothpaste presented as aggravated OLL (7/10) and peri-oral eczema (2/10) in allergic subjects. They also had significantly higher mucosal and OHIP scores compared with those receiving non-flavoured toothpaste. CONCLUSION: In sensitized individuals, oral exposure to carvone gives aggravated oral lesions and/or peri-oral eczema. The lesions mimic OLP and allergic individuals are therefore at risk of not being assessed with regard to flavour contact allergy.

Active sensitization to dimethylthiocarbamylbenzothiazol sulphide: An unexpectedly strong rubber contact allergen.

BACKGROUND: The two dialkylthiocarbamyl benzothiazole sulphides, dimethyl-thiocarbamylbenzothiazole sulphide (DMTBS) and diethylthio-carbamylbenzothiazole sulphide (DETBS) were shown to be good markers of both thiuram and mercaptobenzothiazole sensitivity. OBJECTIVES: To investigate if DMTBS and/or DETBS could be better markers of contact allergy to common rubber additives than the ones currently used. METHODS: Sixty-eight dermatitis patients were patch tested with DMTBS and DETBS, both at 1% in petrolatum (pet). Because of late reactions in 10 patients, these were retested to DMTBS and DETBS in serial dilutions. Tetramethylthiuram monosulphide (TMTM) 1.0% pet was also tested. RESULTS: At the initial reading Days 3 and 7, no reactions were noted to DMTBS or DETBS. At retesting, 10 of the 68 (15%) patients reacted positively to lower concentrations of DMTBS than the initial test concentration. Seven of 8 also reacted to TMTM. Three of them had positive reactions to DEBTS. All 10 patients had reactions to more diluted solutions to DMBTS than to DEBTS (p = 0.0077; Mc-Nemar test, two-sided). CONCLUSIONS: Results speak for patch test sensitization to DMTBS with cross-reactivity to TMTM and also DEBTS. DMTBS and DEBTS could be new markers of rubber allergy but a safe test concentration must be found.

Outbreak of occupational allergic contact dermatitis from a smartphone screen protector glue.

BACKGROUND: Sensitization to acrylates is a concern in the occupational/environmental dermatology field. OBJECTIVE: To describe an occupational allergic contact dermatitis (ACD) outbreak from a smartphone screen protector glue. METHODS: Thirteen affected workers of a chain store selling phone screen protectors were investigated in five Spanish dermatology departments. The glue datasheet and label were assessed. A chemical analysis of the glue was performed. Based on this, some patients underwent additional testing. RESULTS: All patients (all female, mean age: 25) had severe fingertip dermatitis. The datasheet/label indicated that the glue contained isobornyl acrylate (IBOA), a "photoinitiator" and polyurethane oligomer. The company informed us that the ingredients were polyurethane acrylate, "methacrylate" (unspecified), acrylic acid, hydroxyethyl methacrylate, propylmethoxy siloxane, and photoinitiator 184. Isobornyl acrylate (or IBOA) and N,N-dimethylacrylamide (DMAA) were patch tested in eight and two cases, respectively, with negative results. A chemical analysis revealed 4-acryloylmorpholine (ACMO); isobornyl methacrylate (IBMA), and lauryl acrylate in one glue sample. Seven patients were patch tested with dilutions of the identified substances and six of seven were positive for ACMO 0.5% pet. CONCLUSION: An outbreak of occupational ACD, likely from ACMO in a glue is described. Further investigations are needed to corroborate the role played by each compound identified in the chemical analyses.

Carvone Contact Allergy in Southern Sweden: A 21-year Retrospective Study.

Carvone (l-carvone), a mint flavour in spearmint oil, is considered a mild skin sensitizer. Carvone-sensitization may be linked to oral/perioral signs and oral lichen planus, but studies are sparse. The prevalence of patch test reactions to carvone and relevant findings from the positive group were investigated. Records for patch-tested patients at the Malmö clinic, for the period 1996 to 2016, were studied. Carvone-positive and carvone-negative patients were compared regarding patch test data from baseline series and dental series. Dental series-tested carvone-positive patients were also compared with a matched group. A total of 147 out of 4,221 referred patients had a positive patch test to carvone. Sensitized patients had higher mean age and were primarily women; 73% had oral signs and 57% had oral lichen. Concomitant patch test reactions to gold, nickel and mercury were common. In the matched group-comparison carvone-positive patients had a higher frequency of oral lichen, but no difference was found in sensitization to gold and mercury.

Sensitization and cross-reactivity patterns of contact allergy to diisocyanates and corresponding amines: investigation of diphenylmethane-4,4'-diisocyanate, diphenylmethane-4,4'-diamine, dicyclohexylmethane-4,4'-diisocyanate, and dicylohexylmethane-4,4'-diamine.

BACKGROUND: Isocyanates are used in polyurethane production. Dermal exposure to isocyanates can induce contact allergy. The most common isocyanate is diphenylmethane diisocyanate used for industrial purposes. The isomer diphenylmethane-4,4'-diisocyanate (4,4'-MDI) is used in patch testing. Diphenylmethane-4,4'-diamine (4,4'-MDA) is its corresponding amine. Concurrent reactions to 4,4'-MDI and 4,4'-MDA have been reported, as have concurrent reactions to 4,4'-MDI and dicyclohexylmethane-4,4'-diisocyanate (4,4'-DMDI). OBJECTIVES: To investigate the sensitization capacities and the cross-reactivity of 4,4'-MDI, 4,4'-MDA, 4,4'-DMDI, and dicyclohexylmethane-4,4'-diamine (4,4'-DMDA). METHODS: The guinea-pig maximization test (GPMT) was used. RESULTS: The GPMT showed sensitizing capacities for all investigated substances: 4,4'-MDI, 4,4'-MDA, 4,4'-DMDI, and 4,4'-DMDA (all p < 0.001). 4,4'-MDI-sensitized animals showed cross-reactivity to 4,4'-MDA (p < 0.001) and 4,4'-DMDI (all p < 0.05). 4,4'-MDA-sensitized animals showed cross-reactivity to 4,4'-DMDA (p = 0.008). CONCLUSION: All of the investigated substances were shown to be strong sensitizers. Animals sensitized to 4,4'-MDI showed cross-reactivity to 4,4'-MDA and 4,4'-DMDI, supporting previous findings in the literature. The aromatic amine 4,4'-MDA showed cross-reactivity to the aliphatic amine 4,4'-DMDA.

Quantification of l-carvone in toothpastes available on the Swedish market.

BACKGROUND: Toothpastes have widespread use in the population, and contain flavours to give a pleasant and often minty aroma. Flavours are prevalent allergens in toothpastes, and adverse reactions often present as perioral dermatitis or stomatitis. l-Carvone, a mint flavour found in spearmint oil, is one of these allergens. There are few studies on contact allergy to l-carvone, and some of them have indicated a positive relationship with oral lichenoid lesions. OBJECTIVES: To qualitatively and quantitatively investigate the presence of l-carvone in commercially available toothpastes on the Swedish market. METHODS: l-Carvone in 66 toothpastes was analysed with straight-phase high-performance liquid chromatography. The product labels were studied with regard to limonene. RESULTS: l-Carvone was found in 64 of 66 toothpastes (concentration: 0.00005-0.35%). In 10 of these, the concentration exceeded 0.1%. Higher concentrations of l-carvone were found if limonene was listed on the label. CONCLUSION: The majority of toothpastes on the Swedish market contain l-carvone, but the concentration hardly relates to the advertised flavour or labelled ingredients. It is hitherto unknown whether the found concentrations are sufficient for induction of contact allergy in individuals with healthy oral mucosa or in those with oral lichenoid lesions or other mucosal disease.

Is p-tert-butylphenol-formaldehyde resin (PTBP-FR) in TRUE Test® (Mekos test) sensitizing the tested patients?

BACKGROUND: In a population study using TRUE Test®, we noted late reactions to p-tert-butylphenol-formaldehyde resin (PTBP-FR) in 0.5% of subjects tested. OBJECTIVES: In order to explore possible test sensitization, differences in the contents of sensitizers within PTBP-FR in test preparations for TRUE Test® and Finn Chambers® were analysed. Subjects allergic to PTBP-FR and subjects with late reactions to PTBP-FR were retested in order to explore whether these groups reacted to different PTBP-FR sensitizers. PATIENTS/MATERIALS/METHODS: Four individuals with late reactions and 5 subjects with established allergy to PTBP-FR were retested with defined PTBP-FR sensitizers. PTBP-FR constituents in patches from TRUE Test® were analysed with high-performance liquid chromatography. Previously analysed samples of PTBP-FR constituents served as a reference. RESULTS: The pattern of reaction to PTBP-FR sensitizers was similar in both groups. Subjects with suspected sensitization had somewhat stronger reactions than controls. The concentrations of monomers, dimers and trimers were generally higher in the TRUE Test® resin than in reference substances. CONCLUSIONS: Retesting did not add information regarding causes of possible sensitization. Analysis showed that the resin used in TRUE Test® has a lower degree of polymerization or condensation, which may enhance its sensitizing properties. A follow-up of late reactions to PTBP-FR in TRUE Test® should be carried out.

Are gloves sufficiently protective when hairdressers are exposed to permanent hair dyes? An in vivo study.

BACKGROUND: The use of permanent hair dyes exposes hairdressers to contact allergens such as p-phenylenediamine (PPD), and the preventive measures are insufficient. OBJECTIVES: To perform an in vivo test to study the protective effect of gloves commonly used by hairdressers. PATIENTS/MATERIALS/METHODS: Six gloves from Sweden, Italy and Germany were studied: two vinyl, one natural rubber latex, two nitrile, and one polyethylene. The hair dye used for the provocation was a dark shade permanent dye containing PPD. The dye was mixed with hydrogen peroxide, and 8 PPD-sensitized volunteers were tested with the gloves as a membrane between the hair dye and the skin in a cylindrical open chamber system. Three exposure times (15, 30 and 60 min) were used. RESULTS: Eczematous reactions were found when natural rubber latex, polyethylene and vinyl gloves were tested with the dye. The nitrile gloves gave good protection, even after 60 min of exposure to the hair dye. CONCLUSIONS: Many protective gloves used by hairdressers are unsuitable for protection against the risk of elicitation of allergic contact dermatitis caused by PPD.

The necessity of a test reading after 1 week to detect late positive patch test reactions in patients with oral lichen lesions.

OBJECTIVES: Establishing the clinical relevance of contact allergy to dental materials in patients with oral lichen lesions (OLL) may be difficult, and tests are often read only on day 3 or day 4; also, concentration of the tested allergens may vary. Several studies on dermatitis patients have shown that additional positive patch test reactions can be found after day 4. Therefore, the aim of the present study was to analyse the frequency of late positive reactions to potential allergens in patients with OLL. MATERIAL AND METHODS: Eighty-three of 96 consecutive patients with biopsy-verified OLL were patch-tested with a recently developed lichen series. The patches were removed after 48 h and reactions read 3 and 7 days after application. RESULTS: A total of 129 contact allergies were found, and 26 (20.2 %) of the allergic reactions in 23 patients were seen on day 7 only. The 25.2 % increase in positive test reactions with an additional reading on day 7 in addition to day 3 was statistically significant. Metals were the substances with the highest frequency of late positive reactions. CONCLUSIONS: Patients with OLL cannot be considered properly investigated with regard to contact allergy, unless the testing has been performed with mandatory readings on day 3 (or day 4) and day 7. CLINICAL RELEVANCE: Late patch test readings are crucial in order to elucidate the role of contact allergy to dental materials in the aetiology of OLL.

Usage test with palladium-coated earrings in patients with contact allergy to palladium and nickel.

BACKGROUND: Since the EU Nickel Directive came into force, concern has been raised that palladium may increasingly replace nickel in alloys used in jewellery and dentistry, and that it may cause as many allergy problems as nickel. OBJECTIVES: (i) To investigate the clinical relevance of contact allergy to palladium resulting from the wearing of palladium-coated earrings, and (ii) to evaluate the concordance in test results between palladium chloride (PdCl2 ), sodium tetrachloropalladate (Na2 PdCl4 ), and nickel(II) sulfate hexahydrate (NiSO4 .6H2 O), as well as variability in patch test reactivity. MATERIALS/METHODS: Forty female patients with pierced earlobes and previously known contact allergy to palladium and nickel were patch tested with dilution series of nickel and palladium salts. They wore earrings covered with palladium and titanium for 9 weeks to monitor the appearance of any clinical manifestations. RESULT/CONCLUSION: There is a low risk of eczema in palladium-allergic and nickel-allergic individuals when they wear jewellery coated with pure palladium, but further studies are needed to determine whether palladium, when present in alloys, could cause allergic reactions. PdCl2 , like NiSO4 .6H2 O, shows variability in patch test reactivity over time. Furthermore, Na2 PdCl4 seems to be a more sensitive test substance than PdCl2 for the detection of palladium allergy.

A positive cobalt spot test falsely indicating an occupational allergic contact dermatitis caused by cobalt.

BACKGROUND: For investigation of chemical exposure in allergic individuals, spot tests are invaluable. A reagent may react with a specific compound to give a specific typical colour, and thus indicate the presence of the specific substance. Spot tests can give both false-negative and false-positive reactions. To confirm the presence of the substance and quantify it, more sophisticated methods are required. On the basis of a positive cobalt spot test result, a woman was initially diagnosed with an occupational allergic contact dermatitis caused by cobalt. OBJECTIVES: To investigate cobalt release from three different metal weaves to which our patient was occupationally exposed. METHODS: The cobalt gel test and atomic absorption spectroscopy (AAS) were used to investigate the metal weaves. Two types of extract based on artificial sweat and nitric acid, respectively, were investigated with AAS. RESULTS: No cobalt release was demonstrated with AAS. CONCLUSIONS: When a diagnosis of allergic contact dermatitis caused by a sensitizer based on a positive spot test result will have far-reaching consequences, such as change of work, retraining, and claim on and payment of worker's compensation, conformational analysis must be performed.

Analysis of Hexavalent Chromium in Cement Samples From Countries Within and Outside the EU: A Study From the International Contact Dermatitis Research Group.

Background: Allergic contact dermatitis (ACD) caused by hexavalent chromium (Cr(VI)) is often severe and difficult to treat. The content of Cr(VI) in cement can be reduced by, for example, addition of iron(II) sulfate. Since 2005 the content of Cr(VI) in cement is regulated in the EU Directive 2003/53/EC and must not exceed 2 ppm. Since this regulation came into force, ACD caused by cement has markedly been reduced. Objective: To investigate Cr(VI) and total chromium content in samples of cement from countries within and outside the EU. Methods: The members of the International Contact Dermatitis Research Group (ICDRG) were invited to participate in the study with the aim to collect cement samples from geographically different areas. The content of Cr(VI) in the samples was estimated by the diphenyl carbazide spot test, atomic absorption spectroscopy was used to assess the total chromium content. Results: Forty-five cement samples were analyzed, containing amounts of Cr(VI) from <0.1 to >70 ppm. Twenty-one samples contained >2 ppm Cr(VI), 24 contained less. Four of 17 samples from within the EU contained >2 ppm Cr(VI), that is, higher amounts than stipulated in the EU directive, as compared with 17 samples from countries outside the EU. Conclusion: In countries outside the EU, significantly more cement samples contained >2 ppm Cr(VI).

Contact allergy to gold in patients with oral lichen lesions.

The aetiology of oral lichen lesions is obscure. In this study the frequency of contact allergy to gold in 83 patients with oral lichen lesions was compared with that in two control groups, comprising 319 age- and gender-matched patients with dermatitis selected from files and 83 clinically examined dermatitis patients. All patients were tested epicutaneously with gold sodium thiosulphate. The two control groups tested were under examination for a tentative diagnosis of allergic dermatitis not related to oral problems. The frequency of contact allergy to gold was 28.9% in the patients with oral lichen lesions, 18.2% in patients selected from files, and 22.9% in the clinically examined control patients. The difference in frequency between patients with oral lichen lesions and those taken from files was statistically significant.

High frequency of false-positive reactions in attempted patch testing with acrylate/methacrylate mixes.

BACKGROUND: Although acrylate/methacrylate allergy has been frequently reported, until now patch testing with this group of allergens has been unwieldy, requiring the application of large supplementary series in most centres. OBJECTIVES: To formulate and evaluate two mixes of acrylate/methacrylate allergens in three centres (Malmö, Singapore, and Leuven). PATIENTS/MATERIALS/METHODS: All patients tested with the baseline series during the study period were also patch tested with the mixes. Mix 1 consisted of: triethyleneglycol diacrylate (TREGDA) 0.1% wt/wt, 2-hydroxyethyl methacrylate (2-HEMA) 1.0% wt/wt and ethyleneglycol dimethacrylate 1.0% wt/wt in petrolatum. Mix 2 consisted of: TREGDA 0.1% wt/wt and 2-HEMA 2.0% wt/wt in pet. The separate components of the two mixes were also tested simultaneously. RESULTS: There were 25 (5 males; 20 females) positive reactions to mix 1 with 16 in Malmö, 8 in Singapore, and 1 in Leuven. Positive reactions to mix 2 were seen only in Malmö, in 8 female patients. Thus, the positive reaction rate for mix 1 was 8.3% overall (Malmö 7.7%, Singapore 18.6%, and Leuven 2.1%), and that for mix 2 was 2.7% overall (Malmö 3.8%, Singapore 0%, and Leuven 0%). Of the 16 positive reactions to mix 1 in Malmö, only 4 were considered to be true allergic reactions, as the component allergen testing gave totally negative results in 12/16. For mix 2, only 3/8 positive reactions were considered to be true allergic reactions, as the component testing was negative in 5/8. Many doubtful (10-20%) and positive but non-allergic reactions were recorded, leading to early termination of the study. CONCLUSIONS: Although this was an unsuccessful attempt to formulate an acrylate/methacrylate mix, our experience will be useful for those embarking on future attempts to do this.

Hypersensitivity reactions to metallic implants - diagnostic algorithm and suggested patch test series for clinical use.

Cutaneous and systemic hypersensitivity reactions to implanted metals are challenging to evaluate and treat. Although they are uncommon, they do exist, and require appropriate and complete evaluation. This review summarizes the evidence regarding evaluation tools, especially patch and lymphocyte transformation tests, for hypersensitivity reactions to implanted metal devices. Patch test evaluation is the gold standard for metal hypersensitivity, although the results may be subjective. Regarding pre-implant testing, those patients with a reported history of metal dermatitis should be evaluated by patch testing. Those without a history of dermatitis should not be tested unless considerable concern exists. Regarding post-implant testing, a subset of patients with metal hypersensitivity may develop cutaneous or systemic reactions to implanted metals following implant. For symptomatic patients, a diagnostic algorithm to guide the selection of screening allergen series for patch testing is provided. At a minimum, an extended baseline screening series and metal screening is necessary. Static and dynamic orthopaedic implants, intravascular stent devices, implanted defibrillators and dental and gynaecological devices are considered. Basic management suggestions are provided. Our goal is to provide a comprehensive reference for use by those evaluating suspected cutaneous and systemic metal hypersensitivity reactions.