title: Microbiologically Confirmed Tuberculosis: Factors Associated with Pre-Treatment Loss to Follow-Up, and Time to Treatment Initiation.
abstract: BACKGROUND
  The impact of new diagnostics on pre-treatment loss to follow up (Pre-treatment LTFU) has not been widely investigated. The reported rate of pre-treatment LTFU is however lower in studies where Xpert MTB/Rif (Xpert) has been used onsite as opposed to centrally. The use of the Xpert at point of care (POC) could have a role in reducing the pre-treatment LTFU rate among TB patients. We aimed to determine the pre-treatment LTFU rate and the time to treatment initiation as well as to describe associated factors in patients diagnosed with TB using POC Xpert or smear microscopy.
  
  
  METHODS
  Xpert machines were installed at 7 primary healthcare facilities in inner-city Johannesburg. POC Xpert TB testing was the primary diagnostic method for all patients although there were some patients who were tested using only laboratory-based smear microscopy (during power outages or machine operator off-sick). Data on patients' demographics, TB diagnostic test (Xpert or smear microscopy), test result, and time to treatment initiation were collected. Associations and predictors of pre-treatment LTFU and time to treatment initiation were explored.
  
  
  RESULTS
  A total of 1981 people with presumptive TB were tested (1743 using Xpert and 238 using smear). A bacteriological diagnosis of TB was made in 271 patients (90% Xpert; 10% smear). The median time to treatment initiation in the smear group was 9 days (IQR: 4-20) while those tested using Xpert had a median time of 0 days (IQR: 0-0). Pre-treatment LTFU was 22.5% with no difference between diagnostic groups (p = 0.8).
  
  
  CONCLUSIONS
  The Pre-treatment LTFU rate of 22.5% found in this study is much higher than the 5% target of the South African National TB Control Program. POC Xpert resulted in a significantly greater proportion of bacteriologically proven TB patients being started on treatment within 30 days of presentation. No risk factors associated with pre-treatment LTFU were identified.
authors.affiliation: Wits Reproductive Health and HIV Institute, Johannesburg, South Africa.|Department of Clinical Medicine, University of Witwatersrand, Johannesburg, South Africa.
authors.forename: Judith
authors.initials: J
authors.lastname: Mwansa-Kambafwile
authors.affiliation: Wits Reproductive Health and HIV Institute, Johannesburg, South Africa.
authors.forename: Boitumelo
authors.initials: B
authors.lastname: Maitshotlo
authors.affiliation: Wits Reproductive Health and HIV Institute, Johannesburg, South Africa.|Department of Clinical Medicine, University of Witwatersrand, Johannesburg, South Africa.
authors.forename: Andrew
authors.initials: A
authors.lastname: Black
mesh_terms: D000328:Adult; D060085:Coinfection; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D009169:Mycobacterium tuberculosis; D019095:Point-of-Care Systems; D061665:Time-to-Treatment; D014376:Tuberculosis / Q000175:diagnosis* / Q000382:microbiology* / Q000628:therapy