Unusual suction-like contact dermatitis due to ECG electrodes.

A non-atopic 74-year-old man complained of itching vesicular dermatitis on the left side of his thorax, which had flared up 8 days earlier, after a prolonged ECG monitoring. On inspection, many tense erythematous vesicular lesions, strictly arranged in a ring-shape, were observed at every site of application of the electrodes (Fig. 1). Due to the particular shape of the dermatitis a suction reaction was hypothesized. In spite of this, patch tests with GIRDCA series, emulsifiers and fragrance series were performed. Fig. 2. The electrode made of black rubber. Patch tests were also carried out with the ECG gels (as is) used in the out-patient clinic that the patient had visited and with the various pre-packaged gauzes, metal electrodes and pads used as a excipients of the gels used, as well as with the allergens related to ECG monitoring deduced by a review of the literature (1, 2): substitute for ECG paste. polyvinylpyrrolidone as is, tartrazine 1% pet., methylparaben 3% pet., Parabens (1, 2), propyleneglycol, parachlorometaxylenol, ethylparaben 3% pet., propylparaben 3% pet., buthylparaben 3% pet., dyes or pine oil (2) are the allergens most frequently involved hydroxyethylcellulosa 50% alc. and aq.Ω in contact hypersensitivity to ECG gels or pastes. Allergy to Patch tests were all negative except for PPD, which showed a strong various types of topically applied alcohols, such as isopropylpositive reaction (+ at 48 h/+++ at 72 h). alcohol and ethylalcohol, has also been described (3). Inspection of the electrodes revealed that the part which had come Dermatitis may be due also to nickel-plated ECG electrodes into contact with the skin was made of black rubber (Fig. 2). or to rubber straps, which are sometimes used to fasten the ECG electrodes. DISCUSSION Our patient showed a unique sensitization to PPD, a component of black rubber. To our knowledge, allergy to The allergic reactions that appear after ECG monitoring PPD, after ECG monitoring, has never been reported in the may be caused by ECG gels or pastes, alcohols found on literature. This unusual contact dermatitis, apparently not connected with ECG devices, occurred due to the particular composition of the electrodes made of rubber.