This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Medicine
Features of 'Loculatedpleural effusion' on X-ray chest include all except 
Select and explain. 
A. Air bronchogram present, B. In oblique view margins are diffuse in end on, C. Not limited to one bronchopulmonary segmen t, D. Superomedial margin of loculated pleural effusion forms obtuse angle with the mediastinum
A: Air bronchogram present
Answer: A: Air bronchogram present 
Explanation: (A) Air bronchogram present # Presence of air bronchogram excludes any pleural or mediastinal pathology.> Air bronchogram is visibility of bronchi with in parenchymal lesion, so it is found in alveolar pathology as Consolidation Infarction Contusion> Loculation should be considered when a density is considered to be fluid and does not correspond to anatomical location of fissures (loculation can occur within fissures).> It is not in the gravity dependant location.> Note in the upright film on right you are able to see the diaphragm medially, indicating that the fluid is not in the dependent portion.> Empyemas loculate> Consider all loculated effusions as empyema unless proven otherwise.