by Santiago Martínez-Jiménez, MD and Sherief Garrana, MD
Coronal HRCT of a patient with acute infectious bronchiolitis secondary to respiratory syncytial virus (RSV) shows diffuse bilateral tree-in-bud nodules and upper lobe ground-glass opacities. RSV is a common cause of infectious bronchiolitis and has been linked to asthma in children.
Coronal HRCT of a 52-year-old woman with rhinovirus pneumonia shows multifocal ground-glass opacities bilaterally. Rhinoviruses are the predominant cause of the common cold but occasionally cause viral pneumonia.
Axial NECT of a 75-year-old man with herpes simplex virus pneumonia shows multifocal ground-glass opacities and consolidations. Herpes pneumonia is rare but may occur in the setting of burns, transplantation, pregnancy, malignancy, and human immunodeficiency virus infection.
Axial CECT of a 71-year-old woman with human metapneumovirus pneumonia shows bilateral consolidations and a small right pleural effusion. Human metapneumovirus is a common cause of viral pneumonia.
Axial HRCT of a bone marrow transplant recipient who developed parainfluenza virus 3 pneumonia shows scattered bilateral ground-glass opacities . Influenza, respiratory syncytial virus, rhinovirus, and parainfluenza virus are the most common pathogens in this patient population.
Axial NECT of a patient with cytomegalovirus pneumonia and a history of bilateral lung transplantation shows a left upper lobe nodule with surrounding ground-glass opacity , the so-called CT halo sign, which often correlates with perilesional hemorrhage.
Axial NECT of a hematopoietic stem cell transplant recipient with cytomegalovirus infection shows multiple random lung nodules measuring < 10 mm, with surrounding ground-glass opacity . These findings are highly suggestive of a viral infection.
Axial CECT of a 28-year-old man with fever and a skin rash due to varicella-zoster virus infection shows profuse, miliary, 1- to 2-mm nodules scattered throughout the lung.
Axial NECT of a patient with hantavirus pulmonary syndrome shows diffuse symmetric ground-glass opacities with superimposed linear and reticular opacities exhibiting the crazy-paving pattern and small bilateral pleural effusions. The findings were related to diffuse alveolar damage. (Courtesy A.S. Sousa, MD.)
Axial CECT of a 34-year-old woman with influenza A pneumonia shows scattered bilateral peripheral ground-glass opacities and consolidations. The appearance is reminiscent of that of organizing pneumonia, which is often present in severe cases of viral pneumonia.
PA chest radiograph of a 68-year-old man with Middle East respiratory syndrome-Coronavirus (MERS-CoV) shows bilateral asymmetric patchy consolidations most pronounced in the right upper lobe.
Axial CECT of the same patient shows extensive right upper lobe ground-glass opacities with associated reticulation (crazy-paving pattern) and lobular consolidations This infection was initially reported in and near the Arabian Peninsula, but a large outbreak happened in Korea in 2015 associated with a traveler returning from the Arabian Peninsula.
Axial NECT minIP reformation of a patient with H1N1 virus infection shows ground-glass opacity with peripheral consolidation exhibiting the reversed halo sign consistent with organizing pneumonia, a pattern associated with H1N1 infection.
Coronal CECT of a patient with H1N1 pulmonary infection shows patchy areas of ground-glass opacity, bronchial wall thickening, and tree-in-bud opacities .
Axial CECT of a 51-year-old man who presented with dyspnea and fever shows multifocal lobular consolidations and tree-in-bud opacities without pleural effusion. Similar opacities were present in the right lung (not shown). The patient was diagnosed with parainfluenza virus pulmonary infection.
