Background:

According to the guidelines from the American Thoracic Society, posteroanterior and if possible lateral chest radiographs should be obtained if pneumonia is suspected in adults, The chest radiograph continues to be the initial imaging tool to assess the lung parenchyma because its yield in relation to cost radiation dose, availability, and ease of performance is unmatched by other modalities. In immunocompromised patients with suspected pneumonia, CT has been shown to improve pretest probability when forming a differential diagnosis and strengthen clinical decision making, However, there is a paucity of literature regarding the utility of chest CT in immunocompetent patients with chest radiographic findings of pneumonia.

Methods:

We identified 536 patients from our admissions who underwent chest CT between January 2005 and January 2007. Reports of CXR within 24 hours before CT were reviewed to identify patients with findings of pneumonia. The following were the exclusion criteria: recommendation of CT on CXR report and immunocompromised status on chart review. Thirty‐seven patients met the inclusion criteria — 12 women and 25 men, whose mean age was 56 years Age‐ and sex‐matched controls from the floor admissions with CXR findings of pneumonia who did not undergo CT were identified. Charts were reviewed for clinical presentation, management, and follow‐up. Groups were compared using Fisher exact and paired Student t tests.

Results:

The patients were sicker than the controls with more signs and symptoms including auscultation abnormalities, 95% (35 of 37) versus 51% (19 of 37); abnormal sputum, 41% (15 of 37) versus 9% (3 of 37); hypoxemia, 57% (21 of 37) versus 2% (1 of 37); weight loss, 11% (4 of 37) versus 2% (1 of 37); and night sweats, 22% (8 of 37) versus 2% (1 of 37; P < 0.05 each), Clinical management was more extensive for patients than for controls: antibiotics initiated, 100% (37 of 37) versus 47% (18 of 37; P > 0.096); antibiotics changed, 8% (3 of 37) versus 0% (P > 0.089); procedures performed, 14% (5 of 37) versus 6% (2 of 37), P > 0.067; and mean length of stay was 6 5 days versus < 1 (P < 0.05). Eleven percent of the patients (4 of 37) had alternative/additional diagnosis based on CT: lung cancer (2 cases); and TB, lung nodule, and parapneumonic pleuraI effusion (1 each).

Conclusions:

Chest CT was often useful in guiding therapy or providing an alternative diagnosis; however, radiation exposure, length of stay, over‐reading of CT of the chest, making patients undergo more invasive procedures, and more risks have to be kept in mind.

Author Disclosure:

M. Chadi Alraies, none; A. Hamid Alraiyes, none; K. Al‐Okla, none; M. Baibars, none.