American Board of Internal Medicine (ABIM) Certification Practice Exam

What is the gold standard diagnostic test for bronchiectasis?

1. Chest X-ray

2. Magnetic Resonance Imaging

3. High-resolution CT

4. Ultrasound of the Chest

The correct answer is: High-resolution CT

High-resolution CT (HRCT) of the chest is considered the gold standard diagnostic test for bronchiectasis due to its ability to provide detailed images of the airways and surrounding lung tissues. This imaging modality allows for the visualization of bronchial dilation, an essential feature in the diagnosis of bronchiectasis. HRCT is particularly adept at detecting subtle bronchial wall changes and the presence of mucus in the airways, which are critical in establishing the diagnosis and understanding the extent of the disease. Unlike chest X-rays, which might show indirect signs of bronchiectasis but lack the specificity or sensitivity needed for a definitive diagnosis, HRCT can clearly delineate the structural abnormalities associated with the condition. While magnetic resonance imaging (MRI) can also be used in certain scenarios, it is less commonly employed in the evaluation of bronchiectasis compared to HRCT, which has become the preferred tool because of its rapid acquisition time and superior ability to highlight lung parenchyma changes. Ultrasound of the chest is not typically used for the diagnosis of bronchiectasis as it may not provide adequate visualization of the airways and is more commonly reserved for assessing pleural diseases or guiding procedures. Thus, the use of high-resolution CT is firmly established in clinical