Review Question - QID 214289

A 21-year-old man presents to the emergency department for an allergic reaction. He says that he tried sushi for the first time today at a local restaurant. When he first tasted the fish he thought it had a very bitter, peppery taste. After eating it, he suddenly felt warm and flushed. He felt dizzy and developed palpitations, and his vision became blurred. He then states a rash appeared. His friend who was with him states that they had only tried tuna, mahi-mahi, herring, and mackerel. His temperature is 99.0°F (37.2°C), blood pressure is 100/61 mmHg, pulse is 117/min, respirations are 23/min, and oxygen saturation is 93% on room air. Physical exam is notable for the finding in Figure A and bilateral wheezing on pulmonary auscultation with good air movement. Which of the following is the most likely diagnosis?