The diagnostic accuracy of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in mediastinal tuberculous lymphadenitis

Turkish Journal of Medical Sciences Turk J Med Sci (2017) 47: 1874-1879 © TÜBİTAK doi:10.3906/sag-1606-110 http://journals.tubitak.gov.tr/medical/ Research Article The diagnostic accuracy of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in mediastinal tuberculous lymphadenitis 1 2, 1 3 4 1 Onur Fevzi ERER , Serhat EROL *, Ceyda ANAR , Can BİÇMEN , Zekiye AYDOĞDU , Serir AKTOĞU Department of Chest Diseases, Dr. Suat Seren Chest Diseases and Thoracic Surgery Teaching and Research Hospital, İzmir, Turkey 2 Department of Pulmonary Diseases, School of Medicine, Ankara University, Ankara, Turkey 3 Department of Microbiology, Dr. Suat Seren Chest Diseases and Thoracic Surgery Teaching and Research Hospital, İzmir, Turkey 4 Department of Pathology, Dr. Suat Seren Chest Diseases and Thoracic Surgery Teaching and Research Hospital, İzmir, Turkey 1 Received: 22.06.2016 Accepted/Published Online: 03.10.2017 Final Version: 19.12.2017 Background/aim: Mediastinal lymph nodes are the second most commonly affected lymph nodes in tuberculous lymphadenitis. It is often difficult to diagnose tuberculosis in patients with lymphadenopathy without parenchymal lesions. The aim of this study was to describe the diagnostic utility of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in patients with isolated mediastinal tuberculous lymphadenitis (MTLA). Materials and methods: This study included 527 patients who had undergone EBUS-TBNA between December 2012 and December 2014. Patients with the final diagnosis of MTLA were evaluated. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of EBUS-TBNA were calculated. Results: The prevalence of MTLA in all patients who had undergone EBUS-TBNA for mediastinal lymphadenopathy of unknown etiology was 5.2% (28/527). EBUS-TBNA was diagnostic in 21/28 (75%) patients, and the remaining 7 patients required additional procedures for confirmation of diagnosis. Sensitivity, specificity, PPV, NPV, and accuracy of combined cytopathological and microbiological examinations of EBUS-TBNA in the diagnosis of MTLA were 87.5%, 98.5%, 91.4%, 98%, and 94.4%, respectively. There were no major complications. Conclusion: EBUS-TBNA is a safe and effective procedure for the diagnosis of MTLA. When microbiological and cytopathological examinations of samples are combined, EBUS-TBNA demonstrates good diagnostic accuracy and NPV for the diagnosis of MTLA. Key words: Lymphadenitis, tuberculosis, mediastinal diseases, endobronchial ultrasound 1. Introduction Tuberculous lymphadenitis is the most common form of extrapulmonary tuberculosis (EPT) (1). The most commonly affected lymph nodes (LNs) are the cervical, followed by mediastinal, supraclavicular, and inguinal LNs (2). In the International Standards for Tuberculosis Care it is recommended that microbiological confirmation must be made, and diagnostic materials should be obtained for microbiological and histopathological evaluation for diagnosis of EPT (3). While it is relatively easy to obtain lymph node aspiration or excisional biopsy materials from the peripheral lymph nodes, like the cervical lymph node, obtaining material for mediastinal tuberculous lymphadenitis (MTLA) is difficult (4,5). Diagnosis maybe difficult in the absence of accompanying parenchymal involvement; the vast majority of such cases have negative * Correspondence: 1874 sputum smears and cultures. Radiological findings of an adenopathy do not confirm the diagnosis. Moreover, fungal infections or malignancy can also produce similar radiological abnormalities. Mediastinoscopy has been successfully used for MTLA diagnosis for many years (6). However, compared to mediastinoscopy, endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is minimally invasive, with lower morbidity and mortality rates, and can be performed as an outpatient procedure and under conscious sedation. Therefore, EBUS-TBNA has become the first-line procedure for evaluation of mediastinal LNs (7). In this study, we aimed to describe the diagnostic utility of EBUS-TBNA in patients with isolated intrathoracic lymphadenopathy due to tuberculosis. ERER et al. / Turk J Med Sci 2. Materials and methods 2.1. Study design and case selection We retrospectively evaluated our database for patients who underwent EBUS between December 2012 and December 2014. Over the study period, a total of 527 patients underwent EBUS-TBNA for the staging and diagnosis of primary lung cancer, extrapulmonary malignancy, MTLA, sarcoidosis, and a variety of clinical indications. Only patients with a final diagnosis of MTLA were included in the study. 2.2. The EBUS-TBNA procedure All EBUS-TBNA procedures were performed by the same bronchoscopist. The EBUS-TBNA procedure was performed by an EBUS-guided TBNA bronchoscope (7.5 MHz, BF-UC160F; Olympus, Tokyo, Japan) under conscious sedation with intravenous midazolam. An examination of all mediastinal and hilar lymph node stations accessible by EBUS was performed prior to the TBNA procedure. Each target nodal station was punctured at least three times, and one or more tissue core specimens were obtained with a dedicated 22-gauge needle (NA201SX-4022; Olympus). The aspirate was then blown onto a glass slide by pushing air using a 20-mL syringe. All patients provided informed consent before the endoscopic procedure. The study was approved by the institutional ethics committee. 2.3. Cytopathological examination Some amount of aspirate was smeared onto glass slides, air-dried, fixed immediately with 95% alcohol, and stained with hematoxylin and eosin (H&E). The rest of the aspirate was placed into a mixture of formalin and alcohol in order to obtain a cell block for histological examination. A cell block was obtained for all patients. Rapid on-site cytological examination was not available. 2.4. Mycobacterial cultivation, identification, and molecular detection Fine-needle aspiration biopsy specimens were suspended in 1 mL of Middlebrook 7H9 medium and vortexed. Mycobacterial cultivation was performed by the MGIT 960 system (BD Biosciences, Sparks, MD, USA) according to the recommendations of the manufacturer, as described elsewhere (8), and in Lowenstein–Jensen slants (Salubris AS, İstanbul, Turkey). An acid-fast smear preparation by fluorochrome and/or Kinyoun staining was also applied to each processed specimen. Differentiation of M. tuberculosis and nontuberculous mycobacteria was performed by conventional methods (9). Mycobacterial cultures were obtained in all patients. Nucleic acid amplification tests (NAATs) were used as the method of detecting the presence of M. tuberculosis complex DNA directly from clinical specimens during the study period. The test was the BD ProbeTec ET Mycobacterium tuberculosis Complex (DTB) (BD Biosciences) and it was performed and evaluated according to the recommendations of the manufa (...truncated)