Utility of the lateral chest radiograph in the evaluation of patients with a positive tuberculin skin test result.

Abstract

STUDY OBJECTIVES: In the United States, chest radiographs are performed on patients with positive tuberculin skin test (TST) results. It is not known whether, in addition to a single posteroanterior radiograph, a lateral chest radiograph is clinically indicated or cost-effective. We sought to determine the utility of the lateral chest radiograph in evaluating TST-positive adults. DESIGN: Cross-sectional study. SETTING: Tertiary-care hospital. PATIENTS: Adults with positive TST results. MEASUREMENTS: Findings on posteroanterior radiographs alone were compared to posteroanterior and lateral chest radiographs. RESULTS: In 2 of 535 cases (0.4%), lateral chest radiographs revealed a calcified granuloma not visible on posteroanterior radiographs. This finding did not alter patient management. In all other cases, lateral radiographs only confirmed findings seen on posteroanterior chest radiographs. CONCLUSION: Treatment altering findings were always visible on posteroanterior radiographs alone. These results suggest that lateral chest radiographs are not useful in evaluating adults with positive TST results.