LIFE THREATENING ANAPHYLACTIC SHOCK DUE T O SKIN APPLICATION OF CHLORHEXIDINE

Since the introduction of chlorhexidine in the 50's, many authors have observed various hypersensitivity reactions to this agent, including contact dermatitis, photosensitive dermatitis, fixed drug eruption, co ntact urticaria, occupational asthma and other immediate hypersensitiv ity reactions, including severe anaphylactic shock. A 20 year-old-male in good general health and with no history of atopy or allergy to dru gs desinfected a 2 x 2 cm wound with a solution containing chlorhexidi ne 0,05%. Within 2 minutes a generalized urticaria developed, followed by loss of consciousness. The emergency doctor found him in shock wit h no detectable blood pressure, tachycardia, diarrhoea and urine incon tinence. After resuscitation he made a good recovery. One week later h e applied a cream containing chlorhexidine 0,5% and again he developed a generalized urticaria almost immediately. He was referred to our al lergy unit for further investigations. Skin prick tests with chlorhexi dine and a lymphocyte stimulation test (detecting sensitized lymphocyt es in vitro) with a stimulation index of 4,9 were positive. No reactio ns to the other components of the solution and the cream were observed . Healthy volunteers failed to react with chlorhexidine. We diagnosed a type I allergy to chlorhexidine. To our knowledge this is the first reported case, in which a life threatening anaphylactic shock occured after an application of chlorhexidine to a very little skin surface. M any authors reported life threatening reactions only when chlorhexidin e was applied to mucous membranes, while allergic reactions were repor ted rarely and only when chlorhexidine was used on the skin in concent rations higher then 0,05%. In 1984 the Japanese Ministery of Wellfare recommended that the use of this substance on mucous membranes be proh ibited. Our case shows again that chlorhexidine may have a very strong sensitization potential and that life threatening anaphylactic shock can occour even if the product is applied to little wound skin surface s in the recommended concentration of 0,05%. In view of the worldwide and enormous use of chlorhexidine, we should like to call attention ag ain to the risk of this antiseptic causing anaphylactic reactions.