Figure 3. Chest radiograph showing early, subtle Pneumocystis pneumonia–associated abnormalities in both lower lungs of a patient newly diagnosed with AIDS; this diagnosis was unsuspected in the patient, a 63-year-old married man. Magnified images on right show normal lung (top image) and infiltrates adjacent to and behind the heart and overlain by rib (bottom image). Similar differences between the upper and lower lobes are seen in the radiograph on the left. Image used with permission of David Denning (©2016, all rights reserved).