ALL ROADS “LEAD” TO ANAPHYLAXIS: HYPERSENSITIVITY TO ELECTROCARDIOGRAM LEADS

Abstract

Introduction There are multiple case reports of electrocardiogram (ECG) leads causing contact dermatitis, but not anaphylaxis. We present a patient with history of contact dermatitis to ECG leads who had anaphylaxis after inadvertent ingestion of ECG lead conductive gel. Case Description A 47-year-old male with history of coronary artery disease was admitted for chest pain. After ECG was performed, he developed localized pruritic erythematous lesions coinciding with previously placed ECG leads. He had similar reactions to various ECG leads identified as contact dermatitis. He had no changes to medications or foods. The next day, the patient re-attached a displaced ECG lead, touching the conductive gel. He then placed a straw into glass of water and drank through the straw. He developed immediate tongue and facial swelling, acute respiratory distress, and was subsequently intubated for airway protection. He received treatment for anaphylaxis with epinephrine, solumedrol, diphenhydramine, and famotidine and was extubated after 2 days. Discussion Anaphylaxis is an IgE-mediated type 1 hypersensitivity reaction, while contact dermatitis is a T-cell-mediated type 4 hypersensitivity reaction. Though uncommon, documented cases of contact dermatitis related to ECG leads exist, typically caused by polyacrylates, such as propylene glycol, found in the conductive gel. There are no published reports of anaphylaxis to ECG lead materials. Here, ingestion of proposed antigen, the conductive gel, led to a severe type 1 hypersensitivity reaction. This case mimics reactions observed with latex gloves. Natural latex can cause allergic IgE-mediated type 1 reaction, while other chemicals in latex gloves, like accelerators, can cause type 4 reactions.