Figure 1. Community-acquired pneumonia in a 21-year-old HIV-positive woman, CD4 count 684 cells/mm3 , not on highly active antiretroviral therapy. She presented with a 2-day history of cough, fever, and shortness of breath. The chest radiograph shows multifocal airspace consolidations. Gram stain showed gram-positive cocci, but cultures were negative. There was rapid response to antibiotic therapy for bacterial community-acquired pneumonia.
Figure 2. Pneumocystis carinii pneumonia (PCP) in a 31-year-old HIV-positive woman with underlying emphysema. (A) Posteroanterior chest radiograph shows a symmetric, bilateral, perihilar, and basilar distribution of ground-glass opacities and consolidation. The symmetrical distribution is typical of PCP. (B) High-resolution CT (HRCT) image at the level of the bronchus intermedius shows a relatively symmetric distribution of ground-glass opacities, with some areas of more confluent consolidation in the lower lobes. Note extensive underlying emphysema with predominantly paraseptal features.
Figure 3. Cystic pneumocystis carinii pneumonia in a 48-year-old HIV-positive man presenting with shortness of breath and cough. (A) Posteroanterior chest radiograph shows numerous cysts of varying sizes with a diffuse distribution, but relative sparing of lung bases. (B) Coronal CT reformation image shows cysts to greater detail. Also note patchy foci of consolidation in the left upper lobe.
Figure 4. Paradoxical response in a 34-year-old HIV-positive woman, CD4 cell count 59/mm3. She was receiving treatment for pulmonary tuberculosis, and her chest radiograph and spu-tum cultures had become negative. Two weeks after beginning highly active antiretroviral therapy (HAART), she developed fever to 104°F, chills, and cough. Chest radiograph shows development of mediastinal adenopathy (arrows) and diffuse nodular lung opacities. Cultures were negative, and the patient responded to discontinuation of HAART. Several months later, her chest radiograph had normalized (not shown).
Figure 5. Pulmonary histoplasmosis in a 53-year-old HIV-positive man, CD4 cell count 49 cells/mm3. He had cough and sputum production for 4 months. Chest CT showed multiple small pulmonary nodules (arrow), some of which were cavitary (arrowhead). Video-assisted thoracoscopic surgery (VATS) biopsy showed granulomatous infection, positive for Histoplasma capsulatum on culture.
Figure 6. Pulmonary parenchymal lymphoma in a 41-year-old HIV-positive man. He presented with worsening shortness of breath and dry cough. (A) Chest radiograph reveals multiple poorly defined pulmonary nodules without lymphadenopathy. (B) CT image through the lower lobes shows an air bronchogram in the largest mass (arrow). CT-guided biopsy showed malignant large cell lymphoma.
Figure 7. AIDS-related lymphoma presenting as lymphadenopathy. (A) Contrast-enhanced CT image at the level of the left and right main pulmonary arteries shows a large mass involving the anterior and middle mediastinal compartments. The mass results in obstruction of the superior vena cava and encasement of the right pulmonary artery. (B) Coronal image from a gallium scan shows intense uptake in the mediastinal mass.
Figure 8. Lung carcinoma in a 46-year-old HIV-positive man, CD4 cell count 343 cells/mm3. He had a history of cigarette smoking. The chest radiograph shows a large, well-defined mass in the right upper lobe, as well as extensive emphysematous changes. Biopsy revealed focally necrotic non-small-cell carcinoma.
Figure 9. Lymphocytic interstitial pneumonia (LIP) in a 31-year-old man, CD4 cell count 337 cells/mm3 . He presented with a 1-month history of slurred speech but no respiratory symptoms. Chest radiograph shows diffuse, fine nodular changes, best seen in the lower lobes. Surgical biopsy of the right lower lobe showed a bronchiolocentric lymphoid infiltrate accompanied by lymphocytic infiltrates in the interstitium representing a mixture of B and T cells.
Figure 10. Paraseptal emphysema and incidentally detected lung cancer in a 45-year-old HIV-positive woman with history of recurrent "spontaneous" pneumothoraces. High-resolution CT image of the lung apices reveals extensive paraseptal emphysema. Also note the small right apical lung nodule (arrow), which proved to represent lung cancer.
Figure 11. Pulmonary embolism in a 38-year-old HIV-positive man, CD4 cell count 368 cells/mm3 . He presented with signs and symptoms of deep venous thrombosis, shown by Doppler ultrasonography (not shown). Contrast-enhanced chest CT reveals a large right pulmonary artery embolus (arrow), and lung windows (not shown) showed a right lower lobe pulmonary infarct.