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Pneumonia: Difference between revisions
→Imaging of pneumonia
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There are rapid antigen tests of urine for detection of S. pneumoniae and legionella, which can be used for more complicated cases. This is usually not necessary in a typical case of CAP. Atypical bacteria can’t be cultured but the specific pathogen can be determined by serology or PCR. | There are rapid antigen tests of urine for detection of S. pneumoniae and legionella, which can be used for more complicated cases. This is usually not necessary in a typical case of CAP. Atypical bacteria can’t be cultured but the specific pathogen can be determined by serology or PCR. | ||
=== Imaging | === Imaging === | ||
The gold standard for diagnosis is the presence of a new opacity on [[chest x-ray]] in the setting of typical clinical features. The opacity is caused by the consolidation of the tissue, caused by presence of exudate in the alveoli. Chest x-ray is negative in the first 24 – 48 hours. The sensitivity of chest x-ray for pneumonia is low, and so a negative x-ray does not rule it out, especially in the early phases.The chest x-ray findings usually persist for weeks even after symptoms have cleared, so they’re usually not used for follow-up for pneumonia. CT may also visualise pneumonia but is unnecessary for uncomplicated cases. | The gold standard for diagnosis is the presence of a new opacity on [[chest x-ray]] in the setting of typical clinical features. The opacity is caused by the consolidation of the tissue, caused by presence of exudate in the alveoli. Chest x-ray is negative in the first 24 – 48 hours. The sensitivity of chest x-ray for pneumonia is low, and so a negative x-ray does not rule it out, especially in the early phases.The chest x-ray findings usually persist for weeks even after symptoms have cleared, so they’re usually not used for follow-up for pneumonia. CT may also visualise pneumonia but is unnecessary for uncomplicated cases. | ||