Multidrug resistance in tubercular mediastinal adenopathy diagnosed by endobronchial ultrasound-transbronchial needle aspiration

Abstract

Background: Drug resistance in tuberculosis (TB) is a major public health problem. It is easy to assess for drug resistance in pulmonary samples, but the resistance pattern of TB in the mediastinal nodes has not been studied. The aim of this study is to assess the incidence of multidrug resistance in tubercular mediastinal adenopathy with the help of endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration. Materials and Methods: This was a prospective study at a tertiary care teaching hospital in New Delhi where 102 patients with positive mycobacterial cultures from mediastinal lymph node aspirates taken with the help of EBUS were enrolled over 24 months and their drug sensitivity to the first-line antitubercular drugs analyzed. Results: There were 30 cases of drug resistance of 102 culture-positive cases. Of them, 8 patients had multidrug resistant TB (MDR-TB), 16 cases had only single drug resistance, and the remaining 6 cases had more than one drug resistance pattern but not MDR. In our study, the overall incidence of MDR-TB is 7.8% (8/102), although the incidence of MDR-TB in new and re-treatment cases is 2.2% (2/89) and 46.1% (6/13), respectively. Conclusion: Such a high percentage of drug-resistant patients is common in tertiary care hospitals; however, similar percentages may be found in other settings as well. Therefore, all efforts should be made to take samples for Mycobacterium tuberculosis culture from the involved nodes before commencing therapy to avoid treatment failures.

Keywords

• drug-resistant tuberculosis
• endobronchial ultrasound
• mediastinal lymphadenopthy
• tuberculosis