However, there is some literature that evaluates the effectiveness of US for differentiating between lung abscess and empyema, which is the main imaging mimic. This imaging differentiation is important because treatment for these conditions is often different, with abscess often treated with antibiotics and empyema often requiring drainage and antibiotics. In a reported series of 50 and 64 patients with lung abscesses, US was 94% to 96% sensitive and 96% to 100% specific for differentiating between lung abscess and empyema [49-51]. MRI Chest There is limited evidence that MRI has similar sensitivity for abscess compared with CT [40-42]. There are some practical considerations for MRI as an initial imaging modality because clinically unstable patients can be difficult to manage in the MRI environment. If MRI is performed, IV contrast is recommended for the evaluation of lung Pneumonia in the Immunocompetent Child abscess [41]. Additionally, certain pediatric-aged patients typically require sedation, and sedation can result in atelectasis, which can make pleural effusion characterization more challenging. Variant 7: Child. 3 months of age and older. Immunocompetent. Recurrent nonlocalized pneumonia by chest radiograph. Next imaging study. CT Chest A noncontrast chest CT can be used to evaluate for an underlying pulmonary disease, such as postinfectious bronchiectasis, bronchopulmonary dysplasia, and findings such as bullae or bronchiectasis that may indicate a mucociliary deficiency [52]. There is no relevant literature regarding the use of contrast-enhanced CT in this clinical scenario. US Chest There is no relevant literature regarding the use of US as the initial imaging study in this clinical scenario. MRI Chest There is little evidence for MRI as a screening modality for causes of recurrent localized pneumonia, but it can be used to grade known or suspected disease.
Pneumonia in the Immunocompetent Child. However, there is some literature that evaluates the effectiveness of US for differentiating between lung abscess and empyema, which is the main imaging mimic. This imaging differentiation is important because treatment for these conditions is often different, with abscess often treated with antibiotics and empyema often requiring drainage and antibiotics. In a reported series of 50 and 64 patients with lung abscesses, US was 94% to 96% sensitive and 96% to 100% specific for differentiating between lung abscess and empyema [49-51]. MRI Chest There is limited evidence that MRI has similar sensitivity for abscess compared with CT [40-42]. There are some practical considerations for MRI as an initial imaging modality because clinically unstable patients can be difficult to manage in the MRI environment. If MRI is performed, IV contrast is recommended for the evaluation of lung Pneumonia in the Immunocompetent Child abscess [41]. Additionally, certain pediatric-aged patients typically require sedation, and sedation can result in atelectasis, which can make pleural effusion characterization more challenging. Variant 7: Child. 3 months of age and older. Immunocompetent. Recurrent nonlocalized pneumonia by chest radiograph. Next imaging study. CT Chest A noncontrast chest CT can be used to evaluate for an underlying pulmonary disease, such as postinfectious bronchiectasis, bronchopulmonary dysplasia, and findings such as bullae or bronchiectasis that may indicate a mucociliary deficiency [52]. There is no relevant literature regarding the use of contrast-enhanced CT in this clinical scenario. US Chest There is no relevant literature regarding the use of US as the initial imaging study in this clinical scenario. MRI Chest There is little evidence for MRI as a screening modality for causes of recurrent localized pneumonia, but it can be used to grade known or suspected disease.