Emergency and Toxicologycommon
A 34-year-old man in suburban Sydney felt a sharp pinprick on the back of his hand while moving pot plants stacked against the house. Over the next two hours he develops severe pain in the hand spreading up the forearm to the axilla, with nausea and headache. On examination there is a small erythematous mark on the hand with beads of sweat on the surrounding skin, tender axillary lymph nodes, blood pressure 152/94 mmHg and heart rate 96/min. There is no muscle fasciculation, excessive salivation or tingling around the mouth. Which one of the following is the most likely diagnosis?