This study investigated the clinical value of chest radiographs during the 4-week period after diagnosis of severe community acquired pneumonia (CAP) in immune competent hospitalised patients. The time to resolution of pulmonary infiltrates and other radiographic abnormalities caused by infection was compared with resolution of clinical parameters, and factors associated with delayed resolution were identified.

Two hundred and eighty-eight hospitalised patients were followed up between July 2000 and June 2003. Severe pneumonia was defined as a pneumonia severity index score of >90 or according to the American Thoracic Society definition. Patients were treated according to the Dutch guidelines for CAP management. The time for clearance of chest radiographic abnormalities was estimated from chest radiographs taken at 0, 7 and 28 days. Clearance of chest radiographic abnormalities lagged considerably behind clinical improvement at all the assessment time intervals. Raised C-reactive protein levels >200 mg/dl, multilobar infiltrates, dullness on percussion, raised urea levels and Streptomycin pneumoniae infection on admission were independent factors associated with delayed radiographic resolution. Age and co-morbidities did not influence the rate of radiographic clearance.

This study was based on secondary data from a prospective randomised trial on the cost-effectiveness of an early switch from parenteral to oral treatment for severe CAP, which may not be the standard clinical practice in many settings. However, it addressed a pertinent question and might influence the way physicians manage CAP.

Burns AHW, Oosterheert JJ, Prokop M, et al. Patterns of resolution of chest radiograph abnormalities in adults hospitalized with severe community-acquired pneumonia. Clin Infect Dis 2007;45:983–91.