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Community-Acquired Pneumonia — ABIM Board MCQ

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HardInfectious DiseasesCommunity-Acquired PneumoniaABIM Board

A 68-year-old has fever, productive cough, hypoxemia and a new lobar infiltrate. Serum procalcitonin is 0.08 ng/mL. Influenza and SARS-CoV-2 testing are negative. What should be done about antibacterial treatment?

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Correct answer: B — Start empiric systemic antibiotics based on clinical pneumonia

The best answer is “Start empiric systemic antibiotics based on clinical pneumonia”. Clinical and radiographic community-acquired pneumonia should receive prompt empiric antibacterial therapy regardless of a low initial procalcitonin. The biomarker has insufficient sensitivity to exclude bacterial infection at presentation. Serial measurements may later support stewardship in selected settings, but they do not justify delaying initial treatment; inhaled antibiotics or glucocorticoids alone do not cover the likely pathogens.

Reference: 2019 ATS/IDSA Community-acquired Pneumonia Guideline: https://www.idsociety.org/practice-guideline/community-acquired-pneumonia-cap-in-adults