title: Causes and predictive factors associated with "diagnosis changed" outcomes in patients notified as tuberculosis cases in a private tertiary hospital.
abstract: BACKGROUND
  The aim of our study was to evaluate the "diagnosis changed" rate in patients notified as tuberculosis (TB) on the Korean TB surveillance system (KTBS).
  
  
  METHODS
  A total of 1,273 patients notified as TB cases on the KTBS in one private tertiary hospital in 2011 were enrolled in the present study. Patients were classified into three groups: "diagnosis maintained", "diagnosis changed" (initially notified as TB, but ultimately diagnosed as non-TB), and "administrative error" (notified as TB due to administrative errors).
  
  
  RESULTS
  Excluding 17 patients in the "administrative error" group, the "diagnosis maintained" and "diagnosis changed" groups included 1,097 (87.3%) and 159 patients (12.7%), respectively. Common causes of "diagnosis changed" were nontuberculous mycobacterial (NTM) disease (51.7%, 61/118), and pneumonia (17.8%) in cases notified as pulmonary TB, and meningitis (19.5%, 8/41) and Crohn's disease (12.2%) in cases notified as extrapulmonary TB. Being older than 35 years of age (odds ratio [OR], 2.18) and a positive acid-fast bacilli stain (OR, 1.58) were positive predictors and a TB-related radiological finding (OR, 0.42) was a negative predictor for a "diagnosis changed" result via multivariate logistic regression analysis in pulmonary TB cases.
  
  
  CONCLUSIONS
  Because of a high "diagnosis changed" rate in TB notifications to the KTBS, the TB incidence rate measured by the KTBS may be overestimated. Considering the worldwide trend toward increased NTM disease, the "diagnosis changed" rate may increase over time. Thus, when reporting the annual TB notification rate in Korea, the exclusion of "diagnosis changed" cases is desirable.
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Byung Ju
authors.initials: BJ
authors.lastname: Kang
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Kyung-Wook
authors.initials: KW
authors.lastname: Jo
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Tai Sun
authors.initials: TS
authors.lastname: Park
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Jung-Wan
authors.initials: JW
authors.lastname: Yoo
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Sei Won
authors.initials: SW
authors.lastname: Lee
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Chang-Min
authors.initials: CM
authors.lastname: Choi
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Yeon-Mok
authors.initials: YM
authors.lastname: Oh
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Sang-Do
authors.initials: SD
authors.lastname: Lee
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Woo Sung
authors.initials: WS
authors.lastname: Kim
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Dong Soon
authors.initials: DS
authors.lastname: Kim
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Tae Sun
authors.initials: TS
authors.lastname: Shim
keywords: Diagnostic Errors; Incidence; Nontuberculous Mycobacteria; Tuberculosis