Contact Allergy to Allergens in the Swedish Baseline Series Overrepresented in Diabetes Patients with Skin Reactions to Medical Devices - A Retrospective Study from Southern Sweden.

Allergic contact dermatitis is reported among individuals using continuous glucose monitoring systems and insulin pumps. The aim of this study was to describe contact allergy patterns for allergens in the Swedish baseline series and medical device-related allergens among users. Contact allergy to baseline series allergens and isobornyl acrylate was compared between diabetes patients and dermatitis patients patch-tested at the Department of Occupational and Environmental Dermatology during 2017 to 2020. Fifty- four diabetes patients and 2,567 dermatitis patients were included. The prevalence of contact allergy to fragrance mix II and sesquiterpene lactone mix was significantly higher in diabetes patients compared with dermatitis patients. Of the diabetes patients 13.0% and of the dermatitis patients 0.5% tested positive to sesquiterpene lactone mix (p < 0.001). Of the diabetes patients 7.4% and of the dermatitis patients 2.3% tested positive to fragrance mix II (p = 0.041). Of the diabetes patients 70.4% tested positive to medical device-related allergens. Of the diabetes patients 63.0% and of the dermatitis patients 0.2% were allergic to isobornyl acrylate (p < 0.001). In conclusion, not only medical device-related contact allergies, but also contact allergy to baseline series allergens (fragrance mix II and sesquiterpene lactone mix), is overrepresented in diabetes patients who use medical devices.

New device, 'old' allergens. Allergic contact dermatitis caused by the Dexcom G7 glucose sensor.

BACKGROUND: Allergic contact dermatitis (ACD) has been reported as an adverse effect from the use of several glucose sensors and insulin pumps from different manufacturers. Isobornyl acrylate (IBOA) has been identified as a major culprit sensitizer, but also other acrylates and (modified) colophonium have been reported as causes of ACD. OBJECTIVES: To report the two first cases diagnosed with ACD caused by the Dexcom G7 (DG7) glucose sensor. PATIENTS AND METHODS: Two children with suspected ACD from DG7 were patch tested with our medical device series with an addition of selected test preparations including two variants of modified colophonium - methyl hydrogenated rosinate (MHR) and glyceryl hydrogenated rosinate (GHR). Both patients were also tested with acetone extracts made from different parts of the DG7 sensor. The extracts were analysed by gas chromatography-mass spectrometry (GC-MS). RESULTS: Both patients tested positive to IBOA, hydroabietyl alcohol and GHR. In addition, patient 1 had a positive reaction to MHR and patient 2 had a positive reaction to colophonium. The GC-MS analyses showed the presence of IBOA and colophonium-related substances in the DG7 extracts. CONCLUSIONS: Both patients were diagnosed with contact allergy to well-known medical device-related sensitizers. The presence of IBOA and (modified) colophonium in a newly introduced (on the Swedish market in 2023) glucose sensor is remarkable and indicates an inadequate toxicological assessment of the materials used in the sensor.

Allergic contact dermatitis due to 1,6-hexanediol diacrylate in ostomy patients.

BACKGROUND: Many people live with ostomies after life-saving surgery. Ostomy patients often suffer from peristomal dermatitis. Allergic contact dermatitis (ACD) has been reported, mostly due to contact allergy (CA) to topical agents. OBJECTIVES: We present three patients with therapy resistant peristomal dermatitis, suggesting ACD caused by different stoma products. METHODS: Patch testing was performed with baseline series, additional series, and selected allergens. They were also tested with their own ostomy products as is and separate extracts of the products. Extracts were analysed using Gas Chromatography-Mass Spectrometry (GC-MS). RESULTS: In all three patients we diagnosed CA to 1,6-hexanediol diacrylate (HDDA), +++ in case (C) 1 and 3, ++ in C 2. HDDA was detected in C 2's ostomy pouch adhesive and in C 1's and 3's flange extenders used to improve the adhesion of the ostomy pouches. CONCLUSION: Therapy resistant peristomal dermatitis should always be suspected of ACD and patch testing, especially with the patient's own products, should be performed.

Allergic Contact Dermatitis to Linalool Hydroperoxides: Pitfalls in the Diagnostic Process-Findings from a Repeated Open Application Test Study.

Background: Increasing trends of oxidized linalool contact allergy have been reported. However, the impact of reactivity and dose in eliciting allergic contact dermatitis caused by linalool hydroperoxides is insufficiently investigated. Objectives: To perform repeated open application tests (ROATs) using the real-world concentrations of linalool hydroperoxides in patients and control participants. Materials and Methods: Patients who previously had a positive (patients) and a negative (controls) patch test reaction to linalool hydroperoxides 1.0% in petrolatum were patch tested with a dilution series of linalool hydroperoxides preparations and asked to perform ROAT twice daily with 3 concentrations of linalool hydroperoxides creams and a negative control cream for 28 days. The creams contain 44, 140, and 440 PPM of linalool hydroperoxides, representing real-world doses reported in consumer products. Results: Of all 47 participants, 31 were linalool hydroperoxides contact allergy patients, and 16 were controls. One patient had a positive ROAT reaction in the area where cream at the highest concentration of linalool hydroperoxides was applied for 28 days. Conclusions: Repeated exposure to creams containing linalool hydroperoxides at real-life concentrations could rarely elicit an allergic reaction on intact skin after 4 weeks.

Patterns of simultaneous contact allergies in patients with contact sensitization to oxidised linalool and oxidised limonene.

BACKGROUND: Contact allergy rates of linalool and limonene hydroperoxides (HPs) have increased. OBJECTIVES: To demonstrate the patterns of simultaneous positive patch test (PT) reactions and prevalences of multiple contact allergies (MCAs) in patients with contact allergy to linalool and/or limonene HPs. METHODS: A retrospective analysis of consecutive dermatitis patients in 2015-2020 was performed. RESULTS: Of all 4192 patients, 1851 had at least one positive PT reaction. Of these, 410 (22.2%) had MCAs, significantly related to a higher age (p-value = 0.003). Patients with an exclusively positive reaction to linalool HPs but not limonene HPs were shown to have MCAs (p-value <0.001, odds ratio (95% confidence interval) = 4.15 (3.01-5.73)). Patients with simultaneous contact allergies to both linalool and limonene HPs had contact allergies to many other screening and fragrance allergens. CONCLUSIONS: Simultaneous positive PT reactions to allergens in baseline series and fragrances are common in patients with the HPs contact allergy, especially linalool HPs. The pattern of simultaneous PT reactions principally suggested the co-sensitization of the cosmetic allergens.

Contact allergy to oxidised geraniol may be over-represented in individuals with photocontact allergy to ketoprofen.

BACKGROUND: Simultaneous overrepresentations of contact allergies and photocontact allergies are common in individuals with photocontact allergy to ketoprofen. AIMS: To investigate whether contact allergy to oxidised (ox.) geraniol, geraniol, geranial, neral and citral is overrepresented in individuals with photocontact allergy to ketoprofen. METHODS: The contact allergy rates to ox. geraniol, geraniol, geranial, neral and citral in routinely patch tested dermatitis patients were compared with the corresponding rates in individuals with photocontact allergy to ketoprofen. RESULTS: Allergic patch test reactions were noted to ox. geraniol 11% (n = 39, 5.8%), ox. geraniol 6% (n = 12, 1.8%), geraniol 6% (n = 2, 0.3%), geranial (n = 18, 2.7%), neral (n = 7, 1.0%) and citral (n = 15, 2.2%). In those four patients who were diagnosed with photocontact allergy to ketoprofen during the test period, a significant overrepresentation (p = 0.020) of simultaneous contact allergy to ox. geraniol 11% was demonstrated. Overrepresentation of simultaneous contact allergy to various combinations of ox. geraniol, ox. limonene and ox. linalool was also noted in ketoprofen-photoallergic patients. CONCLUSIONS: Contact allergy to ox. geraniol, geranial and citral is common in routinely tested dermatitis patients. There is an overrepresentation of simultaneous contact allergy to ox. geraniol, ox. limonene and ox. linalool in patients with photocontact allergy to ketoprofen.

4,4'-Thiobis(2-tert-butyl-5-methylphenol), an antioxidant in medical devices that may cause allergic contact dermatitis.

BACKGROUND: Antioxidants in medical devices, added to protect polymers or adhesives, may also cause contact dermatitis in some individuals. OBJECTIVES: To present data on sensitization to 4,4'-thiobis(2-tert-butyl-5-methylphenol), an antioxidant detected in some types of medical devices, for six patients that experienced eczematous reactions to different medical devices. METHODS: Patch testing with 4,4'-thiobis(2-tert-butyl-5-methylphenol), 1% pet was performed. Gas chromatography-mass spectrometry (GC-MS) was used for identification of 4,4'-thiobis(2-tert-butyl-5-methylphenol) in different medical device products. RESULTS: Six patients with contact allergy to 4,4'-thiobis(2-tert-butyl-5-methylphenol) also had relevant contact allergic reactions to medical devices containing the antioxidant. The presence of the antioxidant in products was detected using GC-MS analysis. CONCLUSIONS: The antioxidant 4,4'-thiobis(2-tert-butyl-5-methylphenol) may cause allergic contact dermatitis after exposure to different medical devices.

Allergic reactivity for different dilutions of eugenol in repeated open application test and patch testing.

BACKGROUND: Eugenol is a known contact sensitiser included in fragrance mix I. OBJECTIVE: To assess the allergic reactivity to eugenol in different concentrations using patch test as well as repeated open application test (ROAT). METHODS: Overall 67 subjects from 6 European dermatology clinics participated in the study. The ROAT was performed for 21 days twice a day, applying 3 dilutions of eugenol (2.7%-0.5%) and a control. Before and after the ROAT, patch testing with 17 dilutions of eugenol (2.0%-0.00006%) and controls was performed. RESULTS: Out of the 34 subjects with contact allergy to eugenol, 21 (61.8%) showed a positive patch test before ROAT was performed, the lowest positive concentration was 0.031%. The ROAT was positive in 19 (55.9%) of the 34 subjects, the time until a positive reaction occurred was negatively associated with the concentration of the ROAT solution, as well as with the allergic reactivity of the subjects as defined by patch testing. In the patch test after ROAT, 20 of the 34 test subjects (58.8%) showed a positive reaction. In 13 (38.2%) of the 34 test subjects, the patch test result was not reproduceable, still 4 (31.0%) of these 13 subjects developed a positive ROAT. CONCLUSION: Eugenol can provoke a positive patch test reaction in a very low dose; besides, this hypersensitivity may persist even if a former positive patch test is not reproduceable.

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).

Use of sorbitan sesquioleate in patch test preparations and patch testing with the substance-What do our results mean?

BACKGROUND: Sorbitan sesquioleate (SSO) is a sorbitan fatty acid ester, an emulsifier used in topical products and certain patch test preparations. SSO may affect the patch test results. It has been debated whether to include the substance in the baseline series to avoid misinterpretation of the results. OBJECTIVES: To report the prevalence and simultaneous reactions of SSO with other patch test preparations containing SSO as an emulsifier. MATERIALS AND METHODS: A retrospective analysis of 3539 dermatitis patients who underwent patch testing from 2016 to 2020 was performed. RESULTS: The 5-year SSO contact allergy prevalence was 0.48%, and 1.3% had a doubtful reaction. Patients with a stronger positive reaction (2+, 3+) were more likely to react simultaneously to other allergen preparations containing SSO (p value = 0.018). One patient with a strong reaction to SSO reacted positively to all SSO-containing patch test preparations. Definite fragrance allergens could not be identified in the patients who had simultaneous reactions to SSO and fragrance mix (FM) I. CONCLUSIONS: Patch testing with allergen preparations containing SSO affected the patch test interpretation. Fragrance contact allergy could not be ruled out when a patient simultaneously reacted to SSO and FM I. Changing emulsifiers in patch test preparations would be advantageous.

Nonoccupational Allergic Contact Dermatitis to 4-Acryloylmorpholine in Smartwatch Screen Protectors Glue.

BACKGROUND: We recently identified an outbreak of occupational allergic contact dermatitis (ACD) involving workers of a Spanish company selling smartphone protective cases from a glue product. A chemical analysis of one glue sample revealed the presence of 4-acryloylmorpholine among other allergens.The same glue is also used to attach tempered glass protective cases to Apple smartwatches. OBJECTIVE: Our objective was to describe a case series of nonoccupational consumer ACD from the previously mentioned Apple smartwatch protective case glue. METHODS: We evaluated epidemiological and clinical data, as well as patch tests results. RESULTS: Three women were diagnosed with nonoccupational ACD from the adhesive. An annular vesicular inflammatory plaque involving the dorsal aspect of the wrist was initially observed in all. Two of the 3 patients were patch tested with 4-acryloylmorpholine 0.5% with positive strong reactions. Both also strongly reacted to a sample of the glue semiopen tested in a drop of petrolatum. One of them was also positive for various acrylates. CONCLUSIONS: 4-Acryloylmorpholine has been identified in an adhesive used to attach protective cases to smartwatches. Nonoccupational ACD have been described to involve consumers of smartwatches. A UV-curable adhesive used to attach protective cases to smartwatches has been considered to be the culprit.

Contact dermatitis in children caused by diabetes devices.

BACKGROUND: Insulin pumps and glucose monitoring devices improve diabetes mellitus control and enhance patients' quality of life. However, a growing number of adverse cutaneous reactions related to the use of these devices have been reported. OBJECTIVE: To investigate the culprits of localized contact dermatitis in paediatric patients with diabetes caused by insulin pumps and glucose monitoring devices. METHODS: Retrospective analysis of 15 paediatric patients patch tested as part of a clinical investigation for skin reactions associated with insulin pumps and glucose monitoring devices. RESULTS: Seven patients had positive patch test reactions to isobornyl acrylate (IBOA) and five had positive reactions to benzoyl peroxide (BP). Positive patch test reactions to materials from the glucose sensor and/or insulin pump were seen in 10 of the 15 patients. Three had positive reactions to adhesive remover wipe from Smith and Nephew Remove and four had reactions to EMLA plaster. CONCLUSION: A high share of patients showed positive reactions to IBOA and/or their medical devices (insulin pumps or glucose devices). A third of patients showed positive reactions to BP. The presence of additional unidentified allergens cannot be excluded, highlighting the importance of access to a full description of the chemical composition of the devices.

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.

Simultaneous patch testing with fragrance markers in the baseline series and the ingredients of fragrance mixes: An update from southern Sweden.

BACKGROUND: Regularly updating the prevalence of fragrance contact allergy (CA) is important. Patch testing with fragrance markers in the baseline series and the ingredients of fragrance mixes (FMs) is still debated. OBJECTIVES: To update the prevalence and clinical characteristics of patients with fragrance CA. To establish the results of patch testing with individual allergens of FMs. METHODS: A retrospective analysis of 3539 patients with dermatitis who were patch tested with the baseline series and FMs ingredients during 2016 to 2020 was performed. RESULTS: The prevalence of fragrance CA was 13%. About 10% of these patients with fragrance CA would be missed if the individual ingredients were not tested. Unlike hydroxyisohexyl 3-cyclohexene carboxaldehyde, there was no decreasing trend of CA to Evernia prunastri (oakmoss) extract after the EU regulation came into force. Patients with CA from only one ingredient of the mixes or having a weak positive reaction to the ingredients were significantly missed when tested with only the fragrance markers in the baseline series. CONCLUSIONS: Patch testing with individual fragrance allergens is crucial for experts to expand knowledge in the fragrance CA field. The concentrations of the allergens in FMs may need to be adjusted to detect patients with fragrance CA, since some were significantly overlooked.

Further Evidence of Allergic Contact Dermatitis Caused by 2,2'-Methylenebis(6- tert -Butyl-4-Methylphenol) Monoacrylate, a New Sensitizer in the Dexcom G6 Glucose Sensor.

BACKGROUND: Since the spring of 2020, we have seen several patients experiencing severe allergic contact dermatitis (ACD) from the Dexcom G6 glucose sensor after the composition of the sensor's adhesive patch had been changed. We have previously reported the finding of a new sensitizer, 2,2'-methylenebis(6- tert -butyl-4-methylphenol) monoacrylate, in the Dexcom G6 adhesive patch. Three patients with ACD from Dexcom G6 tested positive to this sensitizer. They were also allergic to isobornyl acrylate, a sensitizer present both in Dexcom G6 and in other medical devices previously used by these patients. OBJECTIVE: The aim of the study was to report the first 4 cases sensitized to 2,2'-methylenebis(6- tert -butyl-4-methylphenol) monoacrylate without a simultaneous allergy to isobornyl acrylate. METHODS: The cases were patch tested their own materials, a medical device series, and 2,2'-methylenebis(6- tert -butyl-4-methylphenol) monoacrylate in several concentrations. RESULTS: All 4 cases tested positive to 2,2'-methylenebis(6- tert -butyl-4-methylphenol) monoacrylate at either 1.0% or 1.5% in petrolatum, whereas 20 controls tested negative to both concentrations. CONCLUSIONS: The cases reported here provide further evidence of 2,2'-methylenebis(6- tert -butyl-4-methylphenol) monoacrylate as a relevant culprit sensitizer in patients with ACD from Dexcom G6. However, the initially used patch test concentration (0.3%) did not suffice to elicit positive reactions in these cases, which is why patch testing at 1.5% is recommended.

Contact Allergy to Two Aluminum Salts in Consecutively Patch-Tested Dermatitis Patients.

BACKGROUND: Recently, aluminum chloride hexahydrate (ACH) 10.0% petrolatum (pet) was recommended for patch testing to detect aluminum contact allergy. Aluminum lactate (AL) may be as reliable a test substance as ACH. OBJECTIVE: We aimed to investigate the frequencies of aluminum allergy when ACH and AL were used in patch testing consecutive patients. METHODS: Petrolatum preparations of ACH 10.0% and AL 12.0% were added to the baseline series in 2010-2017. Aluminum chloride hexahydrate 10.0% pet was added to the children baseline series from July 1, 2012, to December 31, 2017. RESULTS: A total of 5448 patients were patch tested with the extended baseline series and 196 children with the extended children baseline series. Forty-eight of the 5448 adults (0.9%) and 10 of the 196 children (5.1%) were diagnosed with aluminum contact allergy. A significant difference was found between the aluminum allergy frequencies in children and adults patch tested with ACH in 2013-2017 (P < 0.001). The difference between the frequencies of contact allergies for the 2 aluminum salts is not statistically significant. CONCLUSIONS: Patch testing with ACH and AL demonstrated similar contact allergy frequencies. To detect aluminum allergy, patch testing with ACH 10.0% pet is recommended. Aluminum chloride hexahydrate 10.0% pet should be considered for inclusion in baseline series for patch testing adults and children.