Evaluation of Ultrasound-guided Fine-needle Aspiration in the Diagnosis of Tuberculous Lymphadenitis

Background: Tuberculous lymphadenitis (TBLN) is the most common extrapulmonary form of tuberculosis, primarily affecting cervical lymph nodes. Accurate diagnosis is crucial for timely treatment, yet challenges persist due to overlapping clinical features with other pathologies. This study evaluates the diagnostic utility of ultrasound (USG) and USG-guided fine-needle aspiration (FNA) compared to cytology, cartridge-based nucleic acid amplification test (CBNAAT), and culture. Methods: A cross-sectional study was conducted on 100 patients with suspected TBLN over 12 months at a tertiary care center. USG features, including hypoechoic nodes, nodal matting, perinodal abscesses, and displaced vascularity, were assessed. FNA samples underwent cytological, CBNAAT, and culture analysis. A composite reference standard integrating clinic-sonographic response to antituberculous therapy (ATT) was used for final diagnosis. Results: Among 100 cases, 74 were confirmed as TBLN. FNA cytology (FNAC) had 88.89% sensitivity and 64.29% specificity, while CBNAAT showed 63.89% sensitivity and 92.86% specificity. USG with ≥2 suggestive features had 64.86% sensitivity and 61.53% specificity. Combining FNAC, CBNAAT, and culture improved diagnostic accuracy (area under the curve: 0.896). Conclusion: USG-guided FNA significantly enhances the diagnostic yield in TBLN. While USG alone has limited specificity, integrating FNAC and CBNAAT improves accuracy. This study supports a multimodal approach for prompt diagnosis and treatment, reducing morbidity in high-burden settings.