title: The additional role of Xpert MTB/RIF in the diagnosis of intrathoracic tuberculous lymphadenitis.
abstract: BACKGROUND
  Diagnosis of intrathoracic tuberculosis (TB) lymphadenitis remains a challenge because of difficulties in obtaining adequate tissue and the lack of a sensitive test. Recently, Xpert MTB/RIF assay is being used for rapid diagnosis of pulmonary TB, but it has not yet been widely validated in intrathoracic TB lymphadenitis. The aim of this study was to assess the additional role of Xpert MTB/RIF in diagnosing intrathoracic TB lymphadenitis using endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) specimen.
  
  
  METHODS
  Consecutive patients who underwent Xpert MTB/RIF assay using EBUS-TBNA specimen from January 2012 and November 2013 at a tertiary referral hospital were recruited. Among them, the cases with malignant lymph nodes were excluded.
  
  
  RESULTS
  Among 73 patients, 13 (17.8%) cases were diagnosed with intrathoracic TB lymphadenitis. In detail, 10 patients were diagnosed using conventional methods only (histology or AFB culture) and 3 patients were additionally diagnosed when adding Xpert MTB/RIF assay. The median time to diagnosis using Xpert MTB/RIF (1 day) was shorter than conventional methods (3 days for histology, 14 days for AFB culture). Rifampin resistance was not detected in any patients.
  
  
  CONCLUSIONS
  In patients with enlarged intrathoracic lymph nodes and low suspicion of malignancy, combination of conventional diagnostic methods with Xpert MTB/RIF could lead to additional and rapid diagnosis of intrathoracic TB lymphadenitis.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jinwoo
authors.initials: J
authors.lastname: Lee
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sun Mi
authors.initials: SM
authors.lastname: Choi
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Chang-Hoon
authors.initials: CH
authors.lastname: Lee
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sang-Min
authors.initials: SM
authors.lastname: Lee
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jae-Joon
authors.initials: JJ
authors.lastname: Yim
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Chul-Gyu
authors.initials: CG
authors.lastname: Yoo
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Young Whan
authors.initials: YW
authors.lastname: Kim
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sung Koo
authors.initials: SK
authors.lastname: Han
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea. Electronic address: mdyspark@gmail.com.
authors.forename: Young Sik
authors.initials: YS
authors.lastname: Park
mesh_terms: D000368:Aged; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D016133:Polymerase Chain Reaction; D012189:Retrospective Studies; D014388:Tuberculosis, Lymph Node / Q000175:diagnosis*
chemical_list: D004269:DNA, Bacterial
keywords: Diagnosis; Lymphadenitis; Tuberculosis