Perioperative anaphylaxis - Don't forget the masked culprit

PERIOPERATIVE ANAPHYLAXIS: DON’T FORGET THE MASKED CULPRIT A. JACQUERIE MD ; F. PIRSON, MDᵇ Chest Unit, Cliniques Universitaires Saint-Luc 1200 Bruxelles ᵇ Chest Unit, Centre de l’allergie Saint Luc Cliniques Universitaires Saint-Luc 1200 Bruxelles. Abstract Chlorhexidine is an effective antiseptic agent, widely used in surgical, clinical and paramedical practice. It is a potentially allergenic substance, which can be associated with severe allergic reaction, especially in perioperative context [1]. Although rare, the prevalence of these hypersentivity reactions remains unknown. We report a case of grade 3 anaphylaxis, caused by the exposure to chlorhexidine during a cardiothoracic surgery, in a 69-year-old man with no history of allergy. At the induction of anesthesia, the patient presented urticaria, rash and severe hypotension. A treatment by intravenous adrenaline and fluid resuscitation has allowed a clinical improvement and the procedure was able to continue. We performed an allergological investigation after 6 weeks. After examination of the anesthetic chart, we tested the different agents administered, and chlorhexidine systematically, with skin prick test, intradermal tests and serum-specific IgE assays (ImmunoCAP, Thermo Scientific). The skin tests [2] and the spIgE were positive for chlorhexidine, and negative for the other substances. In this case, the sources of exposure to chlorhexidine are the gel which was used during the urinary catheterization procedure and skin disinfection for the insertion of central venous catheter. Despite multiple publications on anaphylactic reactions during procedures under general anaesthesia, the role of chlorhexidine is often minimized and underdiagnosed with a risk of re-exposure. It should be recommended that all patients with perioperative allergic reactions will be tested with chlorhexidine due to widespread and often hidden exposure. In the current recommendations, the diagnosis of allergy requires 2 positive diagnostic tests [2]. 246 Words The authors declare that there are no conflicts of interest regarding the publication of this paper. References: 1 Egner W, Helbert M, Sargur R et al. Chlorhexidine allergy in four specialist allergy centres in the United Kingdom, 2009-13 : clinical features and diagnostic tests. Clinical and Experimental Immunology 2017; 188: 380-386 2 Opstrup MS, Malling HJ, Kroigaard M et al. Standardized testing with chlorhexidine in perioperative allergy – a large single-centre evaluation. Allergy 2014; 69:1390-