The diagnostic efficacy of bronchoscopy guided by hand-drawn mapping in the diagnosis of initial treatment for sputum-smear negative peripheral pulmonary tuberculosis

Background: This study aims to evaluate the clinical value and safety of hand–drawn mapping for bronchoscopic navigation combined with radial probe endobronchial ultrasound (RP–EBUS) in the diagnosis of primary peripheral sputum smear–negative pulmonary tuberculosis (SNPTB). Methods: Patients suspected of having peripheral–type primary SNPTB, who were admitted to Southeast University Zhongda Hospital from 2021 to 2024, were retrospectively analyzed. Patients were divided into two groups. The sensitivity, specificity, diagnostic accuracy rate, and area under the receiver–operating characteristic (ROC) curve were evaluated with different diagnostic methods. Results: A total of 212 patients were enrolled, including 149 in the SNPTB group and 63 in the non–SNPTB group. The success rate of ultrasound bronchoscopy exploration is 90.6 %. The sensitivity, specificity, diagnostic accuracy, and AUC value of bronchoscopy guided by hand-drawn mapping were 92.6 %, 95.2 %, 93.4 %, and 0.939, respectively, which were superior to those of T-SPOT detection (P < 0.05). Among the various sampling methods, EBUS–guided bronchoalveolar lavage fluid metagenomic next–generation sequencing (EBUS–BALF mNGS) demonstrated the highest sensitivity (86.6 %), positive predictive value (89.6 %), and AUC (0.917). Conclusions: For peripheral SNPTB, the combination of hand–drawn navigation and RP–EBUS is both safe and effective. EBUS–BALF mNGS demonstrated the highest diagnostic efficiency. When radial ultrasound detects hypoechoic areas of the lesion, it is recommended to perform BALF mNGS. Conversely, in solid lesions, the negative rate of BALF mNGS is relatively high, and combining mNGS with biopsy is recommended to further improve diagnostic efficiency.