D1.76 - Contact dermatitis in diabetic patients with wearable devices: A single-centre study

The incidence of dermatological complications associated with the use of continuous glucose monitoring (CGM) and continuous subcutaneous insulin infusion (CSII) devices is significantly increasing. Application-site reactions are bothersome for patients and represent one of the reasons for discontinuing their use, resulting in poor glycaemic control. However, the differential diagnosis between allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD) is often difficult, and paediatric data regarding the haptens involved are limited.

This pilot observational study included patients with a diagnosis of type1-diabetes who reported dermatitis associated with at least one device. A total of 45 patients were enrolled. Patch tests were applied and removed after 72 hours. A 15-allergen panel has been selected according to commercially available devices. The results were analysed using descriptive statistics. Fisher exact test was used for exploratory comparisons between early-onset (< 1week) and late-onset (≥ 1 month) reactions. 

The primary objective of this study was to identify sensitization patterns to haptens present in CGM and CSII adhesive patches. Secondary objectives were to explore possible associations between patch test outcomes and time of onset, personal and family history of atopy, lipodystrophies, and device used.

Overall, 62.2% of patients were positive to at least one hapten. Colophony was the most common sensitising allergen (57.1% within ACD group), followed by nickel sulphate and ethyl cyanoacrylate. Butyl acrylate, methyl methacrylate, and thiuram mix resulted negative in all patients tested. Patch-positive patients had more late-onset reactions (68.4% vs 28.6%). Lipodystrophies were more common in patch-negative patients (64.7% vs 28.6%). A family history of allergies was reported in 84.4% of cases. All patients reported replacing the device every 3-7 days and worsening of symptoms during summer. 

In this paediatric cohort, the most frequently identified haptens were colophony, nickel sulphate, and ethyl cyanoacrylate. Early-onset reactions tested negative more frequently than late-onset ones, suggesting ICD and/or sensitisation to non-tested haptens, whereas late-onset reactions were more consistent with ACD. Identifying possible haptens can help choose the most appropriate device for the patient and, therefore, offer a better quality of life and better glycaemic control.