Chlorhexidine Hypersensitivity: A Case Report of Delayed Reactions Associated with Epidermal Preparations.

Chlorhexidine is a topical antiseptic that is generally well tolerated in patients, making it a common preparatory substance in various surgical settings. Sparse case reports have identified immediate hypersensitivity reactions after exposure to this substance, especially in patients with a history of atopy. The purpose of this case report is to describe 3 unique presentations of delayed hypersensitivity to epidermal chlorhexidine preparation. Patients undergoing breast surgery by a single surgeon between December 2018 and January 2019 were retrospectively reviewed for incidence of dermatologic complications. Medical and surgical history of patients as well as dermatologic hypersensitivity course were collected. Three patients presented with a delayed hypersensitivity to the epidermal chlorhexidine surgical preparation, ChloraPrep. Each patient developed an erythematous, pruritic maculopapular rash in the distribution of the chlorhexidine application. This occurred beyond the immediate postoperative period-ranging from postoperative days 5 to 35. Initial treatment included the use of 1% hydrocortisone along with a systemic antihistamine. If there was no improvement in symptoms after 3 days, we transitioned patients to 0.5% triamcinolone ointment. If there was no improvement after 5 days on triamcinolone, the patient was reexamined and systemic steroids were prescribed. In each of our cases, all skin changes had resolved within 7-10 days of initial symptoms. Our findings highlight a series of delayed adverse reactions to epidermal chlorhexidine occurring beyond the intraoperative and immediate postoperative period. This case report serves to recognize a unique presentation pattern to ensure that all patients are accurately diagnosed and promptly treated via a systematic treatment algorithm.