A 25-year-old man is brought to the emergency department due to high-grade fever, chills, myalgias, and skin rash, which started on the day of admission. He also had nausea and 3 episodes of profuse watery diarrhea and is now feeling lightheaded. Two days ago, he underwent corrective surgery for a deviated nasal septum but otherwise has no other past medical history. The patient has not traveled recently and has not been around sick contacts. He does not use illicit drugs. His temperature is 39.4 C (103 F), blood pressure is 85/50 mm Hg, and pulse is 116/min. Oxygen saturation is 98% on room air. He is lethargic but has no focal weakness or nuchal rigidity. Examination shows clear lung fields and tachycardia with normal first and second heart sounds. The abdomen is soft and nontender. There is nasal packing in both nostrils. Skin examination shows a diffuse, red, macular rash that also involves the palms and soles. Blood cultures are sent. Item 1 of 2 Which of the following is the most likely cause of this patient's symptoms?

Question

Quizplus · Accepted Answer

Explanation: The patient's clinical scenario and history of nasal packing are suggestive of toxic shock syndrome (TSS). Most patients with TSS have a prodrome of fever, chills, and myalgias that evolves into a multisystemic syndrome (eg, hypotension and shock with dermatologic, gastrointestinal, muscular, renal, and/or neurologic findings); some patients can become abruptly ill within hours. Almost all menstrual and most non-menstrual cases of TSS are due to Staphylococcus aureus and are usually associated with a staphylococcal exotoxin called TSS toxin-1. The pathophysiology involves widespread activation of T cells by exotoxins acting as superantigens (ie, can activate T cells directly without needing to be processed by antigen recognition cells). Massive cytokine production and release occur, leading to the observed clinical manifestations. (Choice B) Bacterial overgrowth and dissemination are characteristic of bacterial endocarditis. (Choices C and D) TSS is not considered an allergic or hypersensitivity reaction. (Choice E) TSS is primarily due to exotoxin effects (although contributions from endotoxins are also possible), not massive bacterial lysis and circulating endotoxin (which would be the main mechanism of septic shock). Educational objective: The pathophysiology of toxic shock syndrome involves widespread activation of T cells by exotoxins acting as superantigens, leading to the massive release of cytokines.

A 25-Year-Old Man Is Brought to the Emergency Department Due