Admission chest radiograph lacks sensitivity in the diagnosis of community-acquired pneumonia.
BACKGROUND
: The clinical and epidemiological significance of community-acquired pneumonia (CAP) with a chest radiograph demonstrating no parenchymal infiltrate has not been studied. We determined the percentage of patients with a clinical diagnosis of CAP who did not have radiographic opacifications and compared this group with patients with CAP and radiographic infiltrates.


METHODS
: Patients admitted with a diagnosis of CAP were identified. Clinical history, physical examination, laboratory studies, and microbiological cultures were reviewed in a random sample of 105 patients. Admission and subsequent chest radiographs were interpreted without knowledge of the clinical data.


RESULTS
: Twenty-one percent (22/105) of patients with a clinical diagnosis of CAP had negative chest radiographs at presentation. Demographic, clinical, and laboratory data were the same in both groups. Fifty-five percent of patients with initially negative chest radiographs who had follow-up studies developed an infiltrate within 48 hours.


CONCLUSIONS
: In patients admitted with a clinical diagnosis of CAP, the initial chest radiograph lacks sensitivity and may not demonstrate parenchymal opacifications in 21% of patients. Moreover, greater than half of patients admitted with a negative chest radiograph will develop radiographic infiltrates within 48 hours. Further studies are needed to develop evidence-based criteria for the diagnosis of CAP.
Departments of Internal Medicine, University of Cincinnati, Ohio, USA. hagamajt@ucmail.uc.edu
Jared T
JT
Hagaman
Gregory W
GW
Rouan
Ralph T
RT
Shipley
Ralph J
RJ
Panos
D017714:Community-Acquired Infections / Q000175:diagnosis / Q000000981:diagnostic imaging; D015897:Comorbidity; D006801:Humans; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000175:diagnosis / Q000000981:diagnostic imaging; D013902:Radiography, Thoracic / Q000592:standards*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index