A 27-year old man had a rhinoplasty. A nasal tampon was placed to control the bleeding. Approximately 4 hours ago he developed headache, muscle...

A 27-year old man had a rhinoplasty. A nasal tampon was placed to control the bleeding. Approximately 4 hours ago he developed headache, muscle aches, and abdominal cramps with diarrhea. He then developed a erythematous 9 rash (resembling sunburn) over much of his body, including his palms and soles. His blood pressure is 80/50 mm Hg. The nasal tampon remains in place. His liver enzyme tests are elevated and there is evidence of moderate renal failure. This patient's illness is likely to be caused by which of the following?