Role of endoscopic ultrasound guided fine needle aspiration/biopsy in the evaluation of intra-abdominal lymphadenopathy due to tuberculosis

BACKGROUND: Intra-abdominal lymphadenopathy due to tuberculosis (TB) poses a diagnostic challenge due to difficulty in tissue acquisition. Although endoscopic ultrasound guided fine needle aspiration/biopsy (EUS-FNA/B) has shown promise in the evaluation of mediastinal lymph nodes, its role in the evaluation of intra-abdominal lymphadenopathy is not clear. AIM: To assess the role of EUS-FNA/B in the evaluation of intra-abdominal lymphadenopathy due to TB. METHODS: This was a retrospective study where patients with intra-abdominal lymphadenopathy who underwent evaluation with EUS-FNA/B were included. TB was diagnosed if the patient had any one of the following: (1) Positive acid fast bacilli (AFB) stain/TB GeneXpert/TB-polymerase chain reaction/AFB culture of tissue sample; and (2) Positive Mantoux test and response to anti-tubercular therapy. EUS-FNA reports, clinical reports and imaging characteristics of patients were recorded for a detailed analysis of patients with TB. RESULTS: A total of 149 patients underwent an EUS-FNA/B from lymph nodes (mean age 51 ± 17 years, M:F = 1.2). Benign inflammatory reactive changes were seen in 45 patients (30.2%), while 54 patients (36.2%) showed granulomatous inflammation with/without caseation. Among these, 51 patients (94.4%) were confirmed to have TB as per pre-defined criteria. Patients with TB were more likely to have hypoechoic and matted nodes [40 patients (67.7%)]. EUS-FNA/B was found to have a sensitivity and specificity of 86% and 93% respectively, with a diagnostic accuracy of 88% in the evaluation of intra-abdominal lymphadenopathy due to TB. CONCLUSION: EUS-FNA/B has a high diagnostic yield with a good sensitivity and specificity in the evaluation of intra-abdominal lymphadenopathy due to TB. However, the validity of these findings in populations with low prevalence of TB needs further evaluation.