Findley and Sahn [37] recommended chest radiographs only when PNA or pneumothorax is suspected. White et al [39] found significant chest radiograph abnormalities in 34% of adults whose asthma exacerbation warranted hospital admission. CT Chest Although our literature search failed to identify any data that suggest that CT serves any significant role in the initial imaging of patients with a high pretest probability of PNA presenting with an acute asthma exacerbation, patients who cannot reliably follow-up or for whom any delay in diagnosis of PNA could be life-threatening may warrant a CT if the chest radiograph is negative or equivocal. Chest radiographs are usually sufficient to diagnose pneumothorax. CT should be reserved for patients who require additional evaluation of their pneumothorax to look for an underlying cause. US Chest US may be a reasonable alternative to chest radiographs to identify PNA [8-12] and pneumothorax [13]. MRI Chest Our literature search failed to identify any data that suggest that MRI serves any significant role in the initial imaging of immunocompetent patients with a high pretest probability of PNA presenting with an acute asthma exacerbation. Acute Respiratory Illness in Immunocompetent Patients Variant 7: Acute COPD exacerbation in immunocompetent patients, uncomplicated (no chest pain, fever, or leukocytosis, no history of coronary artery disease, or heart failure). Initial imaging. Radiography Chest The ATS defines a chronic obstructive pulmonary disease (COPD) flare as an acute worsening of COPD symptoms. Sherman et al [40] studied the usefulness of chest radiographs in 242 patients with acute exacerbations of COPD. Of this group, 135 patients (56%) had asthma, and 107 (44%) had emphysema and chronic bronchitis. Chest radiographs were abnormal in 14% but resulted in significant change in management in only 4.5%.
Acute Respiratory Illness in Immunocompetent Patients. Findley and Sahn [37] recommended chest radiographs only when PNA or pneumothorax is suspected. White et al [39] found significant chest radiograph abnormalities in 34% of adults whose asthma exacerbation warranted hospital admission. CT Chest Although our literature search failed to identify any data that suggest that CT serves any significant role in the initial imaging of patients with a high pretest probability of PNA presenting with an acute asthma exacerbation, patients who cannot reliably follow-up or for whom any delay in diagnosis of PNA could be life-threatening may warrant a CT if the chest radiograph is negative or equivocal. Chest radiographs are usually sufficient to diagnose pneumothorax. CT should be reserved for patients who require additional evaluation of their pneumothorax to look for an underlying cause. US Chest US may be a reasonable alternative to chest radiographs to identify PNA [8-12] and pneumothorax [13]. MRI Chest Our literature search failed to identify any data that suggest that MRI serves any significant role in the initial imaging of immunocompetent patients with a high pretest probability of PNA presenting with an acute asthma exacerbation. Acute Respiratory Illness in Immunocompetent Patients Variant 7: Acute COPD exacerbation in immunocompetent patients, uncomplicated (no chest pain, fever, or leukocytosis, no history of coronary artery disease, or heart failure). Initial imaging. Radiography Chest The ATS defines a chronic obstructive pulmonary disease (COPD) flare as an acute worsening of COPD symptoms. Sherman et al [40] studied the usefulness of chest radiographs in 242 patients with acute exacerbations of COPD. Of this group, 135 patients (56%) had asthma, and 107 (44%) had emphysema and chronic bronchitis. Chest radiographs were abnormal in 14% but resulted in significant change in management in only 4.5%.