Acute coronary syndrome after wasp bite (kounis syndrome)

Abstract Kounis syndrome (KS) is defined as an acute coronary syndrome (SCA) associated with an anaphylactic reaction. A 64–year–old sports man with no previous cardiovascular disease arrived at the emergency room of our Hospital for dyspnoea and chest pain arising during physical activity e preceded by a syncopal episode. During the physical activity (cycling) the patient reported that he had felt an insect bite sensation, with no possibility of precisely identify it. Parameters an admission were: BP 85/45 mmHg, HR 70 bpm, on ECG signs of early repolarization (Fig. 1), blood tests rise in hsTNI (328 ng/L), normal D–dimer. The transthoracic echocardiogram showed no motion abnormalities. In the suspicion of KS, therapy was set up only with ASA and statin, avoiding any drug commonly used to treat allergic reactions that could have worsen the hemodynamic and vasomotor situation by further reducing the coronary perfusion. During hospitalization, in consideration of the clinical picture and cardiovascular risk factors (dyslipidemia and previous smoking), was performed coronary angiography, which showed no obstructive lesions, but during the first injection of contrast showed vasospasm of the ostium of the right coronary artery, dominant (Fig. 2 – left), resolved spontaneously (Fig. 2 – right). The post–procedural hsTNI peak (3953 ng/L) and the presence of the European paper wasp i77 antigen to the serological dosage of the allergens supported the pathophysiology of acute coronary syndrome concomitant with allergic reaction and supported the diagnostic hypothesis of KS type I (without underlying coronary artery disease). The patient was discharged with calcium channel blocker therapy, to reduce coronary vasospasm which characterizes KS, and short–term follow–up was planned with blood tests, exercise stress test and cardiological visit which were normal. KS, though rare, is a clinical entity that should not be underestimated, especially in allergic patients with evidence of SCA without coronary occlusions. The data available in the literature are scarce and it is not clear the medium and long term prognosis. It therefore seems reasonable to follow up the patients as outpatient cardiology visits especially in the first months after the event and schedule instrumental tests control.