Sequential multiple drug hypersensitivity and adequate perioperative disinfection, a case report

A male patient consulted the allergy department for presumed anaphylactic shock. The reaction had occurred 30 minutes after induction of general anaesthesia for laparoscopic exploration of a sub-occlusive colonic mass and the operation was consequently halted. The patient had previously undergone multiple surgeries involving general anaesthesia without complications and had a history of delayed hypersensitivity to povidone-iodine, which had prompted the use of chlorhexidine during previous operations and the one in question here. Serum tryptase levels indicated a transient increase after the incident (139.0 mu g/L at 2 h and 5.5 mu g/L 24 h after the event). Specific IgE (ImmunoCAP, Phadia) for chlorhexidine was elevated (c8 = 32.70 kUa/L) and a skin prick-test for chlorhexidine (0.2%) was positive. Other potential causes were ruled out. Next, epicutaneous tests demonstrated delayed hypersensitivity to povidone-iodine and benzalkonium chloride but not to benzyl alcohol, the latter two of which are often present in mixtures of antiseptic agents and thus require a differential diagnosis. Sodium hypochlorite and alcohol (70%) along with benzyl alcohol and hexamidine were proposed as alternatives. Subsequent use of sodium hypochlorite for skin antisepsis led to no complications. However, further anaphylactic shock occurred 30 minutes after insertion of a central venous catheter pre-soaked with chlorhexidine. In conclusion, we report on a patient presenting sequential multiple drug allergies to antiseptics, including potentially hidden agents that complicate perioperative antisepsis. The allergy workup identified chlorhexidine as the causative agent of the anaphylactic shock and assisted in the selection of effective alternatives. (C) 2020 Elsevier Masson SAS. All rights reserved.