Transmission of Tuberculosis from Patients with Typical Versus Atypical Chest Radiographs: Implications for Automated Systems

• Author / Creator

  Lau, Angela S

• Automated detection of “typical” pulmonary tuberculosis (PTB) on chest radiograph (CXR) is warranted if it can be shown that patients with “typical” (vs “atypical”) CXRs are responsible for most public health consequences.

  Patient demographics and mycobacteriology of all adults (age >14 years) diagnosed with smear-positive PTB in Alberta between January 1, 2006 to December 31, 2008 was abstracted. Pre-treatment CXRs were scored by 3 independent readers as “typical” (having an upper lung zone infiltrate, with or without cavitation, but no discernable adenopathy) or “atypical”.

  A total of 97 smear-positive PTB cases were identified, of whom 69 (71.1 %) had a “typical” CXR. Patients with ‘typical’ CXRs had larger bacillary burdens and more metabolically active bacteria (larger semi-quantitative smears; shorter times-to-culture-positivity) than patients with “atypical” CXRs. Significantly, they are responsible for 78% of TST conversion and 95% of secondary cases.

  PTB patients with “typical” CXRs are responsible for most public health consequences. Accordingly, the development of an automated TB detection system is warranted.

• Subjects / Keywords

  • Tuberculosis Transmission
  • Chest radiographs
  • Tuberculosis
  • Computer aided detection systems

• Graduation date

  Fall 2015

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R34M91G5T

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.