Unexpected Diagnosis of Pulmonary Tuberculosis During Bronchoscopy Using Radial Probe Endobronchial Ultrasound

Background: Bronchoscopy using radial probe endobronchial ultrasound (EBUS) is performed when a peripheral lung lesion (PLL) is suspected to be malignant. However, pulmonary tuberculosis is unexpectedly diagnosed in some patients, and healthcare workers could therefore be exposed to tuberculosis if sufficient precautions are not taken. In this study, we examined the incidence of and factors associated with unexpected diagnosis of pulmonary tuberculosis during bronchoscopy using radial probe EBUS.Methods: This retrospective study included 970 patients who received bronchoscopy using radial probe EBUS between December 2015 and November 2018. Clinical, histological, radiological, and microbiological data were reviewed.Results: Pulmonary tuberculosis was unexpectedly diagnosed in 31 patients (3.2%) during bronchoscopy using radial probe EBUS. Patients with a lower age were significantly more likely to be diagnosed with tuberculosis than elderly patients (odds ratio [OR], 0.951; 95% confidence interval [CI], 0.924–0.978; P = 0.001). Among the various CT findings, a low HUs difference between pre- and post-enhanced CT (OR, 0.976; 95% CI, 0.955–0.996; P = 0.022), the presence of concentric cavitation (OR, 5.211; 95% CI, 1.447–18.759; P = 0.012), and the presence of satellite centrilobular nodules (OR, 22.925; 95% CI, 10.556–49.785; P < 0.001) were independently associated with unexpected diagnosis of tuberculosis.Conclusions: The risk of healthcare workers being exposed to Mycobacterium tuberculosis during bronchoscopy using radial probe EBUS has been underestimated. Our results suggest that healthcare workers in the bronchoscopy suite should consider high-grade respiratory protection when examining patients with risk factors for an unexpected diagnosis of pulmonary tuberculosis.