Inflammation and Immune Pathology USMLE Step 1 Practice Question
A 51-year-old man presents with acute bacterial pneumonia, fever (39.2°C), tachycardia (102 bpm), tachypnea (24/min), and hypoxia (SpO2 88% on room air). Chest X-ray shows consolidation in the right lower lobe. Laboratory studies reveal elevated WBC (16,500/μL) with left shift and normal complement levels. He has intense neutrophilic infiltration in alveolar spaces on biopsy. Which arachidonic acid metabolite is most responsible for attracting neutrophils into the infected tissue?
Answer choices
- ANitric oxide
- BEndothelin
- CLeukotriene B4Correct answer
- DThromboxane A2
- EProstacyclin
- FLeukotriene C4
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