Diagnostic Value of Chest Radiographs in Bedridden Patients Suspected of Having Pneumonia

doi:10.1016/j.amjmed.2009.09.012

The American Journal of Medicine

Volume 123, Issue 1, January 2010, Pages 88.e1-88.e5

https://doi.org/10.1016/j.amjmed.2009.09.012 Get rights and content

Abstract

Objectives

To assess the diagnostic value of the chest radiograph for the diagnosis of pneumonia in bedridden patients, using non-contrast-enhanced high-resolution chest computed tomography (CT) as the gold standard.

Methods

We prospectively evaluated bedridden patients hospitalized with moderate to high clinical probability of pneumonia. Chest radiographs were interpreted in a blinded fashion by 3 observers and classified as definite, normal, or uncertain for pneumonia. Chest CT was obtained within 12 hours of chest radiograph. We applied Bayesian analysis to assess the accuracy of chest radiograph in the diagnosis of pneumonia.

Results

In a 5-month period, 58 patients were evaluated, 31 (53%) were female. Their chest radiographs were interpreted as negative, uncertain, or positive for pneumonia in 31 (53%), 15 (26%), and 12 (21%) patients, respectively, while CT confirmed pneumonia in 11 (35%), 10 (67%), and in 10 (83%). The sensitivity of the chest radiograph to diagnose pneumonia was 65%, the specificity was 93%, the positive and negative predictive values were, respectively, 83% and 65%, while the overall accuracy was 69% (95% confidence interval, 50%-79%).

Conclusions

In bedridden patients with suspected pneumonia, a normal chest radiograph does not rule out the diagnosis, hence, a chest CT scan might provide valuable diagnostic information.

Section snippets

Methods

This study was conducted in a 550-bed university-affiliated hospital and approved by its Internal Review Board. We prospectively evaluated bedridden patients from the Emergency Department and 3 medical departments between January 1 and May 31, 2008, for whom an anteroposterior chest radiograph was ordered to diagnose or exclude pneumonia. An internist (YE), blinded to the patients' chest radiographs, assessed the clinical likelihood of pneumonia by the following criteria, First, vital signs and

Results

After screening 99 patients (Figure), 58 patients were included; 27 (47%) were male (mean age 83.6 years; range 18-97 years). Table 1, Table 2 summarize the clinical and radiological findings. Clinical features and leukocyte counts were not different between the groups. Difficult-to-interpret chest radiographs were common in the uncertain group (47%, P <.001). The proportion of opacities, air bronchogram, and silhouette sign was different between the groups. The proportion of pleural effusions

Discussion

The value of the chest radiograph has not been assessed in bedridden patients. Our results suggest that clinical criteria are insufficient to diagnose pneumonia in bedridden patients, and even after chest radiograph, considerable uncertainty remains (32%-47%). A hands-up maneuver optimized the radiological diagnosis of pneumonia in elderly patients by 30% and boosted interobserver reliability from 0.36 to 0.84 with only 7% suboptimal films.⁷ Our rate of suboptimal radiographs was 16%; chest CT

Acknowledgments

We thank Dr. Daniel Berlowitz and Dr. Shimon Goldberg for critically reviewing the manuscript.

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: Funding: Funded by the Research Fund of Shaare Zedek Medical Center, Jerusalem, Israel.

: Conflict of Interest: No conflict of interest was relevant to the conduct of this study.

: Authorship: All authors meet criteria for authorship and have seen and approved the article.

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AJM onlineBrief observationDiagnostic Value of Chest Radiographs in Bedridden Patients Suspected of Having Pneumonia

Abstract

Objectives

Methods

Results

Conclusions

Section snippets

Methods

Results

Discussion

Acknowledgments

J Emerg Med

Am J Med

J Am Med Dir Assoc

Pneumonia

Clinical prediction rule for pulmonary infiltrates

Ann Intern Med

AJM online
Brief observation
Diagnostic Value of Chest Radiographs in Bedridden Patients Suspected of Having Pneumonia