No abstract

20 mg pet. preparation was the optimal dose for the Finn Chambers.

Contact allergy to dental allergens is a well-studied subject, more so among dental professionals than dental patients. 1632 subjects had been patch tested to either the dental patient series or dental personnel series at the department of Occupational and Environmental Dermatology, Malmö, Sweden. Positive patch tests to (meth)acrylate allergens were seen in 2.3% (30/1322) of the dental patients and 5.8% (18/310) of the dental personnel. The most common allergen for both groups was 2-hydroxyethyl methacrylate (2-HEMA), followed by ethyleneglycol dimethacrylate (EGDMA), triethyleneglycol dimethacrylate, and methyl methacrylate. 47 (29 dental patients and 18 dental personnel) out of these 48 had positive patch tests to 2-HEMA. All 30 subjects who had a positive reaction to EGDMA had a simultaneous positive reaction to 2-HEMA. One dental patient reacted only to 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy) phenyl]propane (bis-GMA). From our data, screening for (meth)acrylate contact allergy with 2-HEMA alone would have picked up 96.7% (29/30) of our (meth)acrylate-allergic dental patients and 100% (18/18) of our (meth)acrylate-allergic dental personnel. The addition of bis-GMA in dental patients would increase the pick-up rate to 100%.

Background Isobornyl acrylate (IBOA) has recently been identified as one sensitizer in the FreeStyle Libre glucose sensor. Analyses with gas chromatography‐mass spectrometry (GC‐MS) have indicated the presence of N,N‐dimethylacrylamide (DMAA) in the sensor. Material and methods Seven patients were referred for patch testing after developing skin reactions when using FreeStyle Libre. All patients were patch tested with IBOA and DMAA. Two patients were tested with adhesive patches that had been removed from the sensors “as is,” and two patients were tested with acetone extracts of materials from the sensor. The extracts were analysed with GC‐MS. Results Six patients reacted to both IBOA and DMAA, and one patient reacted only to DMAA. Positive reactions were also observed in both patients tested with the adhesive patch "as is". One patient reacted to both an extract of the adhesive patch and an extract of the sensor itself. When analysed with GC‐MS, IBOA was found in both extracts and DMAA was found in the extract of the sensor. Conclusion Both IBOA and DMAA may be present in adhesives used in medical devices such as glucose sensors or insulin pumps, and should be patch tested when suspected contact allergic reactions to these products are investigated.

Our results demonstrate that the low concentrations of formaldehyde often found in skincare products by the CA method are sufficient to worsen an existing dermatitis in formaldehyde-allergic individuals.

contact allergy to the TDM is common and inclusion into the Swedish baseline series should be considered.

Diphenylmethane diisocyanate (MDI) is widely used in its polymeric form in the manufacturing of polyurethane products. Previous reports on MDI-related contact allergy have shown a pattern, where patients seem to react to their own MDI-based work material but not to commercial patch-test preparations, which contain 4,4'-MDI. Therefore, we performed chemical analyses of 14 commercial test preparations of 4,4'-MDI obtained from 8 European and 4 American dermatology departments as well as 2 preparations from 2 major European suppliers of patch-test allergens. A new method for monitoring 4,4'-MDI in petrolatum preparations was developed and the determination of 4,4'-MDI as the MDI-dibutylamine derivative using liquid chromatography-mass spectrometry was performed. None of the preparations obtained from the dermatology departments contained more than 12% of the concentration stated on the label. In most cases, 4,4'-MDI content was only a few percentages or less of the concentration stated. 7 of the 14 preparations were analysed before the expiry date. Yet, only 1 of them, a preparation directly obtained from the supplier, came close to the concentration stated on the label. Thus, using these preparations, patients will be tested with a lower concentration than intended, leading to possible false-negative reactions.

The results may have implications for individual diagnosis and prevention and when comparing test results from various centres.