Patch Testing Tools of the Trade Techniques for Marking and Identifying Patch Application Sites

摘要

Epicutaneous patch testing is the diagnostic tool used to confirm the diagnosis of allergic contact dermatitis. Per standardized protocols, chemicals are applied to the skin and removed at 24-48 hours. The sites are marked at the time of removal to allow for easy identification of the sites later. Application sites are then evaluated at later time intervals (between 72 and 120 hours) for signs of inflammation (e.g., redness, induration). This article discusses the techniques for marking those patch tests to secure identification of the patch sites, Allergic contact dermatitis (ACD) is a delayed-type hypersensitivity reaction in the skin that occurs after exposure to a wide variety of chemicals. The gold standard procedure to diagnose ACD is epicutaneous patch testing. Conventionally, chemicals are applied to chambers on adhesive strips, applied to the nondermatitic skin of the patients' backs, and then removed 24-48 hours later. The patch application sites are then evaluated at later time intervals (between 72 and 120 hours) for signs of inflammation (e.g., redness, induration; Wahlberg, 2001). We herein discuss the techniques for marking patch test sites, specifically at the time of removal, while the indentations from patch placement are intact, to secure identification of the patch sites. This article is part of a collaborative series between the American Contact Dermatitis Society and the Dermatology Nurses Association that highlights different technical aspects as well as tips and tools of the trade from partnered provider-nursing teams.