Accuracy of High-Resolution Computed Tomography Chest in Diagnosing Pulmonary Tuberculosis by taking AFB culture findings as Gold Standard

Abstract

Aim: To determine the accuracy of high resolution CT Chest (HRCT) for diagnosis of pulmonary tuberculosis (PTB) by taking AFB culture findings as gold standard. Methods: This validation study was conducted in patients referred for HRCT Chest for diagnosis of pulmonary tuberculosis in OPD/ Radiology unit of CH & ICH within duration of 6 months from September-2020 to February -2021. Patients with suspicion of PTB were included. In all patients, sputum samples were obtained and the AFB test was performed for diagnosis of PTB. After that high resolution CT Chest (HRCT) was performed for diagnosis of PTB. Results: Mean age was 54.67 ± 12.36 years. Male population 54% and female was 46%. AFB culture results for pulmonary. TB was positive in 44 patients and was negative in 56 patients. HRCT findings were positive for pulmonary TB in 46 patients and were negative in 54 patients (Table 1). The sensitivity of HRCT was 81.8%, specificity of HRCT was 82.1%, PPV was 78.3% and NPV was 85.2% (Table 2). Conclusion: HRCT Chest has a sufficient accuracy for PTB diagnosis taking AFB culture results as gold standard. So HRCT Chest can be opted as imaging modality of choice in patients having mixed plain radiographs findings. This will aid in early identification and starting treatment of PTB. Keywords: Accuracy, high resolution computed tomography, pulmonary tuberculosis.