Evaluation of Isobornyl Acrylate Content in Medical Devices for Diabetes Treatment

Allergic contact dermatitis caused by glucose sensors and insulin pumps: A full review: Part 1: Sensors and pumps, adverse cutaneous reactions, allergens, and diabetes devices causing allergic contact dermatitis

During the past 8 years, a large number of reports have appeared on allergic contact dermatitis to glucose sensors and insulin pumps in paediatric and adult patients with type 1 diabetes mellitus. Isobornyl acrylate in one particular sensor sensitised many hundreds of (published) individuals, and many other allergens were discovered in a large number of sensors and pumps. Diagnostic procedures with patch tests proved very complicated, as manufacturers showed a serious lack of cooperation with dermatologists in providing information on the ingredients of their products and samples for patch testing. This two-part article provides a full and detailed review of all aspects of the subject of allergic contact dermatitis to glucose sensors and insulin pumps. Part 1 begins with a general introduction to sensors and pumps, followed by the cutaneous adverse reactions that they have caused and a full account of the allergens in the diabetes devices. In addition, an overview of the glucose sensors and insulin pumps that have caused allergic contact dermatitis is presented. Part 2 presents all published case reports and case series, clinical features of allergic contact dermatitis to sensors and pumps, patch test procedures, differentiation from irritant dermatitis, management of allergic patients and (proposed) legislation.

Deriving a point of departure for assessing the skin sensitization risk of wearable device constituents with in vitro methods

Wearable devices are in contact with the skin for extended periods. As such, the device constituents should be evaluated for their skin sensitization potential, and a Point of Departure (PoD) should be derived to conduct a proper risk assessment. Without historical in vivo data, the PoD must be derived with New Approach Methods (NAMs). To accomplish this, regression models trained on LLNA data that use data inputs from OECD-validated in vitro tests were used to derive a predicted EC3 value, the LLNA value used to classify skin sensitization potency, for three adhesive monomers (Isobornyl acrylate (IBOA), N, N- Dimethylacrylamide (NNDMA), and Acryloylmorpholine (ACMO) and one dye (Solvent Orange 60 (SO60)). These chemicals can be used as constituents of wearable devices and have been associated with causing allergic contact dermatitis (ACD). Using kinetic DPRA and KeratinoSens™ data, the PoDs obtained with the regression model were 180, 215, 1535, and 8325 μg/cm2 for IBOA, SO60, ACMO, and NNDMA, respectively. The PoDs derived with the regression model using NAMs data will enable a proper skin sensitization risk assessment without using animals.

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.

Screening Allergenic Potencies of Skin-Contact Products Using the Human-Derived THP-1 Cell Activation Test

With the prevalence of allergic contact dermatitis (ACD) from the usage of skin-contact products, like wearable, skin care, and hair care products, screening their skin sensitizing potential is necessary, for the sake of alleviating the consequent public health impact. In the present study, a total of 77 skin-contact products classified by four categories, watch bands (WBs), skin care products (SCPs), hair care products (HCPs), and rubber gloves (RGs), were investigated, using an optimized in vitro assay of human cell line activation test (h-CLAT). Extracting the products using neutral artificial sweat simulated well the practical usage scenarios, and testing the extracts showed that 26 of them were allergy test positive, including nine WBs, six SCPs, two HCPs, and nine RGs. The allergenic response was mainly characterized by the induction of CD54 expression, and diverse paradigms of CD54 and CD86 levels were observed by analyzing dose-response curves, which could also be influenced by the compromised viability of the THP-1 cells. The data implicated the intricate regulation by different contributors to suspicious ingredients in the test samples. Altogether, a promising methodology for testing skin allergy potential was well established for commonly used commodities by neutral artificial sweat extraction coupled with h-CLAT screening. The findings would be of great help in tracing the potential allergens in practical products and improving their qualities.

Contact Dermatitis to Diabetes Medical Devices

Skin adverse reactions to diabetes medical devices have been reported frequently over recent years. Adhesives attaching glucose sensors and continuous insulin infusion sets to the skin are proven to cause both allergic contact dermatitis and irritant contact dermatitis in patients with diabetes mellitus. Several allergens contained in adhesives and/or parts of medical devices are documented to cause allergic contact dermatitis, with acrylate chemicals being the most common culprit-especially isobornyl acrylate (IBOA), but also 2,2'-methylenebis(6-tert-butyl-4-methylphenol) monoacrylate or cyanoacrylates. Epoxy resin, colophonium and nickel were also identified as causative allergens. However, repetitive occlusion, maceration of the skin and resulting disruption of the skin barrier seem to have an impact on the development of skin lesions as well. The purpose of this study is to highlight the burden of contact dermatitis triggered by diabetes medical devices and to show possible mechanisms responsible for the development of contact dermatitis in a group of diabetic patients.

Prevalence and Description of the Skin Reactions Associated with Adhesives in Diabetes Technology Devices in an Adult Population: Results of the CUTADIAB Study

Objective: The use of continuous glucose monitoring (CGM) systems and continuous subcutaneous insulin infusion (CSII) devices adhering to the skin can lead to skin reactions. The objective was to determine the prevalence and consequences of skin reactions at CGM or CSII sites in a large unbiased population. Research Design and Methods: This is a cross-sectional multicenter study. All adult patients with diabetes seen in consultation over a period of 7 months and using or having used a system with skin adhesives (in the last 10 years) were included and filled out a self-assessment questionnaire. Results: Among 851 patients, skin reaction was reported in 28% with CGM and 29% with CSII. Patients reporting reactions were more frequently women using CGM and CSII, and CGM users had type 1 more often than type 2 diabetes (P < 0.001). Manifestations were similar for reactions to CGM and CSII: redness and pruritus in 70%-75% of patients with reactions, pain in 20%-25%, and vesicles and desquamation in 12%-15%. Manifestations occurred within the first 24 h of first use in 22%-24% of patients with reactions to CGM and CSII, but after more than 6 months in 38% and 47% of patients with reactions to CGM and CSII, respectively. Device use was definitively stopped in 12% of patients with reactions to CGM (3.2% of all users) and 7% with reactions to CSII (2.1% of all users). Conclusions: Skin reactions were common, with similar presentations in CGM and CSII users. Manifestations suggested skin irritation rather than allergies. These reactions rarely led to the definitive discontinuation of the use of the device.

Contact dermatitis in children caused by diabetes devices

BACKGROUND

Insulin pump and glucose monitoring devices improve diabetes mellitus (DM) control and enhance patients' quality of life. However, a growing number of adverse cutaneous reactions related to the use of these devices has been reported.

OBJECTIVE

To investigate the culprits of localized contact dermatitis in pediatric patients with diabetes caused by insulin pump and glucose monitoring devices.

METHODS

Retrospective analysis of 15 pediatric patients patch tested as part of a clinical investigation for skin reactions associated with insulin pump 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 benzoyl peroxide. 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. This article is protected by copyright. All rights reserved.

Contact allergy to the Dexcom G6 glucose monitoring system -role of 2,2'-methylenebis(6-tert-butyl-4-methylphenol) monoacrylate in the new adhesive

BACKGROUND

Skin reactions to the glucose monitoring systems Dexcom G5 and G6 have been rare. In 2019, the components of the adhesive were exchanged for better skin fixation. Since then, more and more patients experienced severe skin reactions. A few months ago, 2,2'-methylenebis(6-tert-butyl-4-methylphenol) monoacrylate (MBPA) was identified as a new component in the adhesive of the G6 model. Furthermore, it was suspected that isobornylacrylate (IBOA) was also a component of the exchanged adhesive.

OBJECTIVES

Our objective was to investigate if MBPA plays a major role in the increasing skin problems of patients without a history of IBOA-sensitization. Furthermore, our aim was to examine whether IBOA is contained in the newer model adhesive and may also contribute to allergic contact dermatitis (ACD).

PATIENTS AND METHODS

Five patients with a newly occurred ACD caused by the glucose monitoring system Dexcom G6 were investigated. Patch testing including MBPA in 3 different concentrations, as well as IBOA were performed. Gas chromatography-mass spectrometry of the newer system Dexcom G6 was carried out.

RESULTS

All patients were shown to be sensitized to MBPA, while MBPA 0,5% showed the strongest reaction. On the other hand, IBOA was tested negative.

CONCLUSION

In our study group MBPA was observed to be the triggering allergen of the recently changed adhesive.

The automated pancreas: A review of technologies and clinical practice

Insulin pumps and glucose sensors are effective in improving diabetes therapy and reducing acute complications. The combination of both devices using an algorithm-driven interoperable controller makes automated insulin delivery (AID) systems possible. Many AID systems have been tested in clinical trials and have proven safety and effectiveness. However, currently, none of these systems are available for routine use in children younger than 6 years in Europe. For continued use, both users and prescribers must have sound knowledge of the features of the individual AID systems. Presently, all systems require various user interactions (e.g. meal announcements) because fully automated systems are not yet developed. Open-source systems are non-regulated variants to circumvent existing regulatory conditions. There are risks here for both users and prescribers. To evaluate AID therapy, the metric data of the glucose sensors, 'time in target range' and 'glucose management index', are novel recognized and suitable parameters allowing a consultation based on real glucose and insulin pump download data from the daily life of people with diabetes. Read out via cloud-based software or automatic download of such individual treatment data provides the ideal technical basis for shared decision-making through telemedicine, which must be further evaluated for general use.

Modern diabetes devices for continuous blood sugar measuring: Limitations due to contact allergies

During the past years, diabetes diseases have increased significantly worldwide. However, new technologies such as continuous glucose measurement using a subcutaneous sensor are developing just as rapidly. A continuous improvement in insulin pump therapy is also contributing to an improved quality of life. A common feature of these modern devices for diabetes therapy is that they remain fixed in place on the skin for several days. In recent years, skin reactions, in particular pronounced contact dermatitis due to the devices and their adhesives have been increasingly reported. In particular, isobornyl acrylate, which used to be included in a glucose measurement sensor set, was identified as a main allergen. Development of contact allergy can result both in a necessity to quit the measuring system and in allergic cross-reactions to other systems.

Allergic contact dermatitis caused by dipropylene glycol diacrylate in the Omnipod® insulin pump

BACKGROUND

Cases of allergic contact dermatitis (ACD) caused by isobornyl acrylate (IBOA) in the Omnipod® insulin pump have previously been reported.

OBJECTIVES

To present three cases of patients with ACD caused by a new allergen in the pump, and results from chemical analyses.

METHODS

Omnipod pumps from different batches were analysed by gas chromatography-mass spectrometry. Aimed testing, with the department's medical device (MD) series and substances identified in the pump including dipropylene glycol diacrylate (DPGDA) at 0·01% and 0·1% in petrolatum (pet.), was performed. Patch testing also included extracts from the device, the adhesive patch as is, and allergens from baseline series.

RESULTS

All patients tested positive to 0·1% DPGDA in pet., and two patients additionally to a 0·01% concentration. DPGDA was found in extracts of the Omnipod pumps brought by the patients. An Omnipod pump from an earlier batch contained tripropylene glycol diacrylate, IBOA, N,N-dimethylacrylamide, di(ethylene glycol)ethyl ether acrylate (DEGEA) but no DPGDA. One of the patients reacted positively to all of these allergens except DEGEA, which was not tested.

CONCLUSIONS

When suspecting ACD to MDs, DPGDA at 0·1% in pet. should be tested. The contents of Omnipod have changed over time. Patch testing with updated test series and relevance assessment of positive reactions is a delicate task. Children, with lifelong use of MDs, risk contracting many allergies with potential cross-allergies. A question should be raised as to whether these low molecular weight acrylates should be used at all in devices constantly worn on the skin.

Extraction With Sweat-Sebum Emulsion as a New Test Method for Leachables in Patch-Based Medical Devices, Illustrated by Assessment of Isobornylacrylate (IBOA) in Diabetes Products

BACKGROUND

The increasing offering of patch-based medical devices is accompanied by growing numbers of reported adverse skin reactions. Procedures for testing leachables according to ISO 10993 may not be optimal for lipophilic substances that can be mobilized on skin by sweat and sebum. We propose an improved extraction method for targeted analysis of leachables using low volumes of a sweat-sebum emulsion. The approach is illustrated by the analysis of isobornylacrylate (IBOA), a compound found in some devices and suspected for allergenic potential.

METHOD

Three patch-based products were tested: an implantable device for continuous glucose monitoring (CGM), an intermittently scanned CGM (isCGM) device, and a micro-insulin pump. Quantification of IBOA was performed by gas chromatography and allergenic potential of IBOA levels was assessed by the KeratinoSens cell assay. Different combinations were used for extraction solvent (isopropanol, 5% ethanol-water solution, and sweat-sebum emulsion), extraction volumes (complete immersion vs partial immersion in 2 mm of solvent), and extraction time (3, 5, and 14 days).

RESULTS

Isobornylacrylate was only found in the isCGM device. About 20 mg/L IBOA were eluted after 3 days in isopropanol but only about 1 mg/L in ethanol-water. Sweat-sebum emulsion dissolves IBOA better and gives a more stable solution than ethanol-water. Decomposition of IBOA solutions requires adjusted extraction timing or correction of results. In the sweat-sebum extract, IBOA levels were about 20 mg/L after 3 days and about 30 mg/L after 5 days, clearly above the threshold found in the KerationSens assay for keratinocyte activation (10 mg/L).

CONCLUSION

Extraction by low volumes of sweat-sebum emulsion can be a superior alternative for the targeted simulating-use assessment of leachables in patch-based medical devices.

Skin Reaction Report Form: Development and Design of a Standardized Report Form for Skin Reactions Due to Medical Devices for Diabetes Management

BACKGROUND

Skin reactions due to medical devices for diabetes management have become a common problem in diabetes technology. There is a varying degree in how detailed skin reactions are described in scientific literature and diabetes practice, and no uniform structured documentation is given. Whereas most articles only describe findings, some others already document final diagnoses, such as contact dermatitis. Furthermore, inconsistent wordings for comparable issues were used.

METHODS

A more detailed and standardized documentation, possibly facilitated by a generally accepted guideline for structured descriptions, of skin reactions could be helpful to enable better differentiations between the described skin reactions. Therefore, a report form to assess skin reactions due to medical devices in diabetes therapy was developed and will be presented in this article.

RESULTS

The one-page report form is divided into four categories and a separate instruction paper. Beside general information the form includes the location, size, severity and duration of skin appearances, the grading of itching, and suspected diagnoses.

CONCLUSION

A consistent use of the form in daily practice and clinical trials could facilitate a fast and standardized documentation and help to evaluate the occurrence and severity of different skin reactions due to medical devices in diabetes management.

Contact Dermatitis From Glucose Sensors In Spain: A Multicentric Approach

BACKGROUND

Allergic contact dermatitis from glucose sensors may interfere with their ongoing application.

OBJECTIVE

To evaluate a series of Spanish patients with contact dermatitis to glucose sensors regarding former sources of contact allergens, patch test results and outcomes from the ongoing use of the device.

METHODS

A series of patients with contact dermatitis from glucose sensors was investigated in eight dermatology departments across Spain epidemiologic features, brands, latency time to develop dermatitis, the ability to continue using the devices as well as the patch test results.

RESULTS

Thirty patients were evaluated mean age: ²⁰ .⁹³ years. ⁶⁶ .⁷ % were children and ⁶⁶ .⁷ % female. ⁹⁰ .⁰ % used Freestyle Libre FSL. ⁸ /^{26 30} .⁸ % reacted to isobornyl acrylate IBOA and ² /^{20 10} .⁰ % to N,N dimethylacrylamide DMAA. The mean latency time to develop dermatitis was ⁹ months. ¹⁶ /^{29 55} .² % patients continued using the same sensor causing the reaction. ¹³ /^{29 44} .⁸ % were unable to continue using the sensor due to severe reactions. Of them, ⁵ were positive to IBOA, one to IBOA and DMAA; one to DMAA; one to colophony and ¹ to isopropyl alcohol wipes. In one patient the outcome was unknown.

CONCLUSION

The frequency of sensitization to IBOA and DMAA, was lower than in other European series, but similar to a previously published Spanish article. Legislation requiring manufacturers to provide information regarding medical devices composition and cooperate with the investigation of contact dermatitis is urgently needed. This article is protected by copyright. All rights reserved.

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.

Five-Month Follow-up Shows No Improvement in Dermatological Complications in Children With Type 1 Diabetes Using Continuous Glucose Monitoring Systems and Insulin Pumps

BACKGROUND

A Danish study showed that 90% of the pediatric patients who participated had some time experienced dermatological complications due to treatment with continuous subcutaneous insulin infusion (CSII). This follow-up study describes dermatological complications due to CSII and/or continuous glucose monitoring (CGM) between the two study periods and includes health-related quality of life (HrQoL) measurements.

METHODS

A total of 138 patients (95%) out of 145 patients from the initial study answered an online questionnaire regarding dermatological complications related to CSII and/or CGM, five months later. A second questionnaire (DISABKIDS) regarding HrQoL was sent out to those 138 of which 111 patients completed it. The patients were aged from 2 to 20 years. Descriptive statistics, χ² tests, and univariate and multivariate analyses were used to analyze the data.

RESULTS

In total, 81% of the 138 patients continued to have dermatological complications at follow-up. Itching was the most frequently reported complication. Patients using Enlite reported more dermatological complications than those using Libre. In total, 79% of the patients who used barrier cream in the initial study still had dermatological complications five months later. Age, gender, Body Mass Index (BMI), or HbA1c levels showed no significant association with dermatological complications. Patients who perceived dermatological complications as a greater problem had lower HrQoL scores.

CONCLUSION

Once dermatological complications start to appear, they become chronic, indicating that the treatments currently available are inadequate. Patients perceiving dermatological complications as a greater problem were associated with lower HrQoL. These findings highlight the need for additional preventive studies.

The Influence of Skin Thickness on Flash Glucose Monitoring System Accuracy in Dogs with Diabetes Mellitus

Simple Summary

A flash glucose monitoring system (FGMS) has been validated for use in dogs with diabetes mellitus and diabetic ketoacidosis. It continuously measures the glucose in the interstitial fluid through a small filament (5 mm long) inserted under the skin. Interstitial glucose concentrations are reportedly comparable to whole blood glucose concentrations. However, several factors can influence the performance of interstitial sensors, including the proportion of interstitial fluid in a tissue. The influence of skin thickness on flash glucose monitoring system accuracy has not been investigated in previous studies; therefore, the aim of this study was to evaluate whether FGMS accuracy is affected by skin thickness. On the basis of our results, skin thickness seems to affect FGMS measurements; the mean bias was significantly inversely correlated (p = 0.02; r = −0.6) with the mean skin thickness, and clinical accuracy according to ISO 15197:2013 criteria was observed only in dogs with skin thickness > 5 mm, with 99% of the results falling in zone A + B of the Parkes consensus error grid analysis. In dogs with thin skin (<5 mm), the clinical accuracy was low, and the results should be interpreted with caution.

Abstract

A flash glucose monitoring system (FGMS) has been validated for use in diabetic dogs. However, it is unknown whether skin thickness affects FGMS measurements. The aim of this study was to evaluate whether FGMS accuracy is affected by skin thickness. Fourteen client-owned diabetic dogs on insulin treatment were prospectively enrolled in the study. The dogs were divided into two groups according to their ultrasound-measured skin thickness: dogs with skin thickness < 5 mm (Group 1) and dogs with skin thickness > 5 mm (Group 2). On days 1, 7 and 14, glucose curves were obtained simultaneously using the FGMS and a validated portable blood glucose meter. Paired measurements were used to calculate the mean bias and to determine accuracy according to ISO 15197:2013 criteria. The mean bias was significantly inversely correlated (p = 0.02; r = −0.6) with the mean skin thickness. Clinical accuracy was observed only in Group 2, with 99% of the results in zone A + B of the Parkes consensus error grid analysis. In conclusion, skin thickness seems to affect FGMS measurements, and the device is accurate in dogs with thicker skin (>5 mm); in dogs with thin skin (<5 mm), the clinical accuracy is low, and the results should be interpreted with caution.

A review of acrylates: Super glue, nail adhesives, and diabetic pump adhesives increasing sensitization risk in women and children

Allergic contact dermatitis (ACD) is a cutaneous type IV hypersensitivity immune reaction mounted against substances in contact with the skin to which the patient has been sensitized. ACD is common, affecting approximately 72 million Americans per year, and is more common in women. One common contact allergen group is acrylates, which are monomers that are polymerized in the making of glues, adhesives, and plastic materials. It is the monomers that are sensitizing, whereas the final polymers are inert. Acrylates were the 2012 Contact Allergen of the Year with the specific acrylate, isobornyl acrylate, being the 2020 Contact Allergen of the Year. This article reviews the history of acrylate use, epidemiology, and both known and emerging sources of acrylates resulting in ACD.

Contact Allergy-Emerging Allergens and Public Health Impact

Contact allergy (sensitisation) and allergic contact dermatitis (ACD) resulting from it have a considerable public health impact. For the present review, all pertinent articles were systematically searched via Medline and Web of Science™; additionally, all available issues of the journals "Contact Dermatitis" and "Dermatitis" were manually searched, covering the years 2018-2019, thereby extending and re-focusing a previous similar review. New allergens, or previously described allergens found in a new exposure context or of other current importance, are described in sections according to substance classes, e.g., metals, preservatives, fragrances. As a common finding in many investigations, a lack of information on product composition has been noted, for instance, regarding a newly described allergen in canvas shoes (dimethylthiocarbamylbenzothiazole sulfide) and, most notably, absence of co-operation from manufacturers of glucose-monitoring devices and insulin pumps, respectively. These latter devices have been shown to cause severe ACD in a considerable number of diabetic patients caused by the liberation of isobornyl acrylate and N,N'-dimethylacrylamide, respectively, as demonstrated by an international collaboration between dermatologists and chemists. Improved and complete ingredient labelling for all types of products, and not just cosmetics, must be put on the legislative agenda.

[Contact allergy due to insulin pumps and glucose sensor systems]

The design and development of insulin pumps and various glucose sensor systems has an enormous impact on life quality of diabetic patients. Surveillance and therapy of diabetes has improved due to the new diabetic devices, which are affixed to the patients' skin for several days. Since their introduction, irritant and allergic contact dermatitis have been frequently reported. Patients often acquire contact sensitization to isobornyl acrylate, N,N-dimethylacrylamide or formerly to 2‑ethyl-cyanoacrylate. These contact allergens were found in the patch, in the glue to affix the box on the patch or in the casing of the system itself. Development of contact allergy to substances of these systems may result in the need to abandon modern diabetic devices.