Inflammation and Immune Pathology USMLE Step 1 Practice Question
A 52-year-old woman with severe rheumatoid arthritis started on infliximab two months ago presents with productive cough, fever (38.9°C), and weight loss. Vital signs show HR 102/min, BP 118/76 mmHg, RR 20/min, SpO2 98% on room air. Chest X-ray reveals apical cavitary lesions. Tuberculin skin test is positive; sputum acid-fast bacilli smear is pending. She denies night sweats. Which mechanism best explains how this biologic therapy predisposed her to this infection?
Answer choices
- ANeutralization of interferon alpha suppresses antiviral defense
- BNeutralization of IL 4 blocks class switching to IgE
- CNeutralization of IL 10 enhances macrophage activation
- DNeutralization of IL 5 impairs eosinophil activation
- ENeutralization of TNF alpha disrupts maintenance of granulomasCorrect answer
- FNeutralization of IL 2 prevents T cell proliferation and differentiation
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