American Board of Internal Medicine (ABIM) Certification Practice Exam

How is nonresponsive pneumonia defined?

1. Lack of significant improvement in 48 hours

2. Lack of significant clinical response within 72 hours of therapy

3. Persistence of fever after 24 hours

4. Occurrence of new symptoms within a week

The correct answer is: Lack of significant clinical response within 72 hours of therapy

Nonresponsive pneumonia is defined by the lack of significant clinical response within 72 hours of therapy. This timeframe is critical because it provides a clear window to assess the effectiveness of the treatment being administered. In most cases, effective antibiotic therapy should lead to observable improvement in symptoms such as reduced fever, improved respiratory function, and overall patient wellbeing within this period. When a patient does not show significant clinical improvement within 72 hours, it raises concerns about several factors. It might suggest that the initial diagnosis was incorrect, the causative organism is resistant to the chosen antibiotic, or there are complications such as abscess formation or empyema that are not responding to standard treatment. Identifying nonresponsive pneumonia is crucial to prompt further evaluation and adjustment of the treatment strategy. The other definitions do not accurately capture the standard criteria for nonresponsiveness. A lack of significant improvement in 48 hours may seem reasonable, but it does not align with the established 72-hour benchmark. Similarly, the persistence of fever after 24 hours does not encompass the broader clinical picture necessary for assessing pneumonia treatment response. Lastly, the occurrence of new symptoms within a week is more indicative of disease progression rather than a direct measure of treatment response timing.