Kounis syndrome: an underestimated emergency.

Summary: Background. Kounis syndrome (KS) is defined as a rare cause of an acute coronary syndrome associated with systemic allergic reactions. To establish the prevalence of KS among the patients with diagnosis of anaphylaxis, we described clinical features, cardiological and allergological outcomes of patients evaluated in our allergy outpatient clinic. Methods. A retrospective study was carried out in the Allergy Unit of Novara hospital, from January 2008 to March 2020. Skin tests and in vitro tests were performed with suspected etiological agents. Results. We found 9 adults with KS (2%) out of 444 subjects who had experienced anaphylactic reactions (4/9 to Hymenoptera stings, 5/9 to drugs). Conclusions. The present study highlights the importance of suspicion of KS that appears not so uncommon in patients with anaphylaxis. KS seems to be a rare disease because unrecognized in diagnosis of anaphylaxis.