Peri-operative anaphylaxis: beyond drugs and latex.

1990s [7–9] . We and other study groups have shown that a significant proportion (5–10%) of IgE-mediated anaphylaxis occurring during general anaesthesia is triggered by chlorhexidine [8, 10, 11] . To put this into perspective, the incidence rate of peri-operative (all causes) anaphylaxis during anaesthesia has been estimated to be 1 in 10,000–20,000 in France and Australia [12, 13] . Hong et al. [14] recently reported an interesting case in International Archives of Allergy and Immunology. This concerned recurrent anaphylaxis triggered by chlorhexidine used for skin and wound cleansing in a critically ill patient with necrotising fasciitis, septic shock and acute renal impairment on a background of hypertension, type 2 diabetes mellitus and coronary artery disease. It is not clear if the patient developed anaphylaxis after the first surgery because this may have been masked by underlying sepsis and was managed with intravenous fluids and inotropic support. However, the subsequent episodes, in particular the third and fourth, when his general condition had improved significantly, manifested as acute hypotension, bronchospasm and flushing peri-operatively, which meet the World Allergy Organisation (WAO) diagnostic criteria for anaphylaxis [15] . However, anaphylaxis was not suspected until after the fourth episode, and was confirmed by a modest elevation in acute serum tryptase (16.7 μg/l). Interestingly, the patient developed Kounis syndrome, a likely consequence of coronary hypoperfusion, thus highlighting the importance of prompt recognition and treatment with adrenaline to reverse hypotension. This case can be used to illustrate some ‘clinical pearls’ for anaesthetists and allergists. First, anaphylaxis should Chlorhexidine gluconate is an antiseptic that has been used worldwide in clinical practice since 1954. It is available as a 0.5–4.0% solution and has a broad spectrum of activity against Gram-positive and Gram-negative bacteria, facultative anaerobes, yeasts and HIV [1] . It is employed to decontaminate people and medical devices. Healthcare-associated infections are the most common adverse events occurring in hospitalised patients and are reported in up to 10% of inpatients in acute-care hospitals [2] . Hand-washing with chlorhexidine is an effective means of eliminating skin flora by 86–92%, and is crucial for combatting and reducing the incidence of methicillinresistant Staphylococcus aureus (MRSA) infection [1, 3, 4] . The counter argument is that increased rates of exposure to chlorhexidine have probably contributed to greater sensitisation and the emergence of IgE-mediated anaphylaxis, which is sometimes near-fatal, particularly in the context of surgical procedures. The first case of chlorhexidine-induced allergic shock was reported in the Japanese literature by Takeda et al. [5] in 1985. A PubMed search using the key words ‘chlorhexidine’ and ‘anaphylaxis’ showed 97 hits in the period 1974–2015, with 2, 15, 37 and 43 publications in 1974–1984, 1985–1994, 1995–2005 and 2006–2015, respectively, mostly in the form of case reports or series. These publications prompted the US Food and Drug Administration (FDA) to issue an alert to the medical fraternity about the possibility of serious anaphylactic reactions to chlorhexidine-impregnated medical devices [6] . The literature on chlorhexidine allergy compares the emergence of the sensitisation and allergy to chlorhexidine to the latex allergy epidemic that was feared in the Published online: August 12, 2015