Kounis Syndrome, an Unrecognized Presentation of Perioperative Anaphylaxis in a Transplant Candidate.

A 52-year-old male presented for kidney transplantation with pretransplant echocardiography showing normal left ventricular chamber size and systolic function. After the induction of general anesthesia, a latex urinary catheter was placed. Within 12 min, the patient presented with diaphoresis, diarrhea, mean arterial pressure of 30–40 mmHg, and electrocardiogram (ECG) ST-elevations. Echocardiography showed global akinesis with diminished biventricular contractility and dilated four chambers. He had no response to IV phenylephrine and vasopressin boluses. Presumed an ST-elevation myocardial infarction occurred as the mean arterial pressure further dropped to 20 mmHg, the decision to use the extracorporeal membrane oxygenation (ECMO) machine before proceeding to percutaneous coronary intervention (PCI) was made. Epinephrine (20 mcg) was given in an attempt to avoid complete cardiopulmonary collapse. Echocardiography then showed a return of function in the right ventricle and inferior wall, while the septum and the anterior wall continued to be hypokinetic. This prompted the start of the epinephrine infusion (0.1 mcg/kg/min). The mean arterial pressure improved to mid-60s mmHg, ECG ST-elevation resolved, and echocardiography showed global improvement in contractility. Now suspecting Kounis syndrome, the transplant surgery, ECMO placement, and PCI procedure were canceled. Acute serum tryptase (serum tryptase sample taken within 2 hours after onset of anaphylaxis) and serial serum troponin levels were obtained.