title: Impact of Xpert MTB/RIF testing on tuberculosis management and outcomes in hospitalized patients in Uganda.
abstract: BACKGROUND
  The clinical impact of Xpert MTB/RIF for tuberculosis (TB) diagnosis in high HIV-prevalence settings is unknown.
  
  
  OBJECTIVE
  To determine the diagnostic accuracy and impact of Xpert MTB/RIF among high-risk TB suspects.
  
  
  METHODS
  WE PROSPECTIVELY ENROLLED CONSECUTIVE, HOSPITALIZED, UGANDAN TB SUSPECTS IN TWO PHASES: baseline phase in which Xpert MTB/RIF results were not reported to clinicians and an implementation phase in which results were reported. We determined the diagnostic accuracy of Xpert MTB/RIF in reference to culture (solid and liquid) and compared patient outcomes by study phase.
  
  
  RESULTS
  477 patients were included (baseline phase 287, implementation phase 190). Xpert MTB/RIF had high sensitivity (187/237, 79%, 95% CI: 73-84%) and specificity (190/199, 96%, 95% CI: 92-98%) for culture-positive TB overall, but sensitivity was lower (34/81, 42%, 95% CI: 31-54%) among smear-negative TB cases. Xpert MTB/RIF reduced median days-to-TB detection for all TB cases (1 [IQR 0-26] vs. 0 [IQR 0-1], p<0.001), and for smear-negative TB (35 [IQR 22-55] vs. 22 [IQR 0-33], p=0.001). However, median days-to-TB treatment was similar for all TB cases (1 [IQR 0-5] vs. 0 [IQR 0-2], p=0.06) and for smear-negative TB (7 [IQR 3-53] vs. 6 [IQR 1-61], p=0.78). Two-month mortality was also similar between study phases among 252 TB cases (17% vs. 14%, difference +3%, 95% CI: -21% to +27%, p=0.80), and among 87 smear-negative TB cases (28% vs. 22%, difference +6%, 95% CI: -34 to +46%, p=0.77).
  
  
  CONCLUSIONS
  Xpert MTB/RIF facilitated more accurate and earlier TB diagnosis, leading to a higher proportion of TB suspects with a confirmed TB diagnosis prior to hospital discharge in a high HIV/low MDR TB prevalence setting. However, our study did not detect a decrease in two-month mortality following implementation of Xpert MTB/RIF possibly because of insufficient powering, differences in empiric TB treatment rates, and disease severity between study phases.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, San Francisco General Hospital, University of California San Francisco, San Francisco, California, USA.
authors.forename: Christina
authors.initials: C
authors.lastname: Yoon
authors.forename: Adithya
authors.initials: A
authors.lastname: Cattamanchi
authors.forename: J Lucian
authors.initials: JL
authors.lastname: Davis
authors.forename: William
authors.initials: W
authors.lastname: Worodria
authors.forename: Saskia
authors.initials: S
authors.lastname: den Boon
authors.forename: Nelson
authors.initials: N
authors.lastname: Kalema
authors.forename: Winceslaus
authors.initials: W
authors.lastname: Katagira
authors.forename: Sylvia
authors.initials: S
authors.lastname: Kaswabuli
authors.forename: Cecily
authors.initials: C
authors.lastname: Miller
authors.forename: Alfred
authors.initials: A
authors.lastname: Andama
authors.forename: Heidi
authors.initials: H
authors.lastname: Albert
authors.forename: Pamela
authors.initials: P
authors.lastname: Nabeta
authors.forename: Christen
authors.initials: C
authors.lastname: Gray
authors.forename: Irene
authors.initials: I
authors.lastname: Ayakaka
authors.forename: Laurence
authors.initials: L
authors.lastname: Huang
mesh_terms: D000328:Adult; D000995:Antitubercular Agents / Q000494:pharmacology / Q000627:therapeutic use; D003710:Demography; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D016019:Survival Analysis; D061665:Time-to-Treatment; D016896:Treatment Outcome; D014376:Tuberculosis / Q000175:diagnosis* / Q000188:drug therapy* / Q000401:mortality; D014454:Uganda / Q000453:epidemiology
chemical_list: D000995:Antitubercular Agents