Transmission of Tuberculosis from Patients with Typical Versus Atypical Chest Radiographs: Implications for Automated Systems
Date
Author
Institution
Degree Level
Degree
Department
Supervisor / Co-Supervisor and Their Department(s)
Examining Committee Member(s) and Their Department(s)
Citation for Previous Publication
Link to Related Item
Abstract
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.