Impact of trends in new and emerging contact allergens

Allergic contact dermatitis represents a T cell-mediated, delayed-type hypersensitivity response to exogenous agents. While allergic contact dermatitis is one of the most common causes of skin disease encountered by dermatologists, emerging trends within the field are in constant flux, as influenced by ever-changing industry practices and evolving consumer behaviors. Although certain allergens continue to predominate, new chemicals are frequently being introduced, thus shifting the pattern of allergen exposure and sensitization. This review examines the impact of trends in new and emerging contact allergens, with particular attention to clinical contexts in which these agents may be encountered. In addition, we offer a working knowledge of these allergens’ characteristics, sources, and relevance, while outlining recommendations to accurately evaluate, diagnose, and provide appropriate counseling for these diseases.

Severe allergic contact dermatitis to two different continuous glucose monitoring devices in a patient with glycogen storage disease type 9b

Continuous glucose monitoring (CGM) systems are of great value for patients with disorders of impaired glucose homeostasis, including glycogen storage diseases. We report on an 8-year-old girl with glycogen storage disease type 9b who developed severe allergic contact dermatitis to two different continuous glucose monitoring systems, FreeStyle^® Libre and Dexcom^® G6. Our case highlights the impact of sensitization for pediatric patients, the urgent need for open labeling of components by pharmaceutical and device manufacturers, and the need for avoidance of skin sensitizers in medical devices.

Position statement: The need for EU legislation to require disclosure and labelling of the composition of medical devices

BACKGROUND

In recent years, skin reactions secondary to the use of medical devices (MD), such as allergic contact dermatitis have increasingly been observed (e.g. to continuous blood sugar monitoring systems, insulin pumps, wound dressings, medical gloves, etc.): this is regarded as a developing epidemic. Lack of labelling of the composition of MD, as well as frequent lack of cooperation of manufacturers to disclose this relevant information, even when contacted by the clinician for the individual case of an established adverse reaction, significantly impede patient care.

OBJECTIVES

To advocate for full ingredient labelling in the implementation of EU regulation for MD.

METHODS

This position paper reviews the scientific literature, the current regulatory framework adopted for MD to date, and the likely impact, including some costs data in case of the absence of such labelling.

RESULTS

Efforts made by several scientific teams, who are trying to identify the culprit of such adverse effects, either via asking for cooperation from companies, or using costly chemical analyses of MD, can only partly, and with considerable delay, compensate for the absence of meaningful information on the composition of MD; hence, patient management is compromised. Indeed, without knowing the chemical substances present, physicians are unable to inform patients about which substances they should avoid, and which alternative MD may be suitable/tolerated.

CONCLUSION

There is an urgent need for full and accurate labelling of the chemical composition of MD in contact with the human body.

Contact dermatitis caused by glucose sensors-15 adult patients tested with a medical device patch test series

BACKGROUND

Several cases of allergic contact dermatitis (ACD) to the glucose sensor FreeStyle Libre have been reported. Isobornyl acrylate (IBOA) and N,N-dimethylacrylamide (DMAA) are known culprit allergens.

OBJECTIVES

To evaluate patients with suspected ACD to FreeStyle Libre in a standardized manner, present causative allergens, and assess patient-reported implications.

METHODS

A total of 15 patients with suspected ACD to FreeStyle Libre were patch tested with the Swedish baseline series and a new medical device series. IBOA and DMAA were tested at 0.1% and 0.3% in petrolatum (pet.). Readings were performed on day (D) 3 and D7. Background data, details on skin reactions, and associated implications were assessed using a questionnaire.

RESULTS

Thirteen patients were sensitized to IBOA and four to DMAA. Two positive reactions to IBOA and one to DMAA were seen only at 0.3% concentration on D7. Median duration of sensor use before dermatitis onset was 6 months. Half the number of the patients took precautions in everyday life due to sensor-related skin reactions. Six patients discontinued sensor usage.

CONCLUSIONS

Patients with suspected ACD to glucose sensors should be evaluated with a relevant patch test series containing IBOA and DMAA. Adding the 0.3% pet. concentration is recommended. The reading on D7 is necessary.

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.