title: Diagnostic dilemma: treatment outcomes of tuberculosis patients with inconsistent rifampicin susceptibility.
abstract: OBJECTIVE
  A retrospective clinical trial to evaluate treatment outcomes in adults with smear-positive tuberculosis (TB) and discordant rifampicin (RMP) resistance results.
  
  
  METHODS
  A total of 2156 smear-positive TB patients underwent both conventional and Genechip drug susceptibility testing (DST) for RMP resistance. All 49 patients with discordant results treated with either a first-line or second-line regimen were analysed.
  
  
  RESULTS
  Of 30 Type I cases (Genechip-resistant, conventional DST-susceptible) receiving the first-line regimen, 4 had a favourable outcome and 5 failed treatment. The 21 remaining Type I cases were treated with the second-line regimen, of whom 18 had a favourable outcome. Second-line regimen thus resulted in significantly more favourable outcomes than first-line treatment (P = 0.032). Among Type II cases (Genechip-susceptible, conventional DST-resistant), 13/19 received the first-line regimen, and 7 had a favourable outcome. The six Type II cases treated with the second-line regimen all had favourable outcomes.
  
  
  CONCLUSIONS
  Patients with discordant RMP DST results who receive second-line regimens may have a better clinical response than those treated with the first-line regimen. Patients infected with fluoroquinolone-resistant Mycobacterium tuberculosis strains were observed to have a significantly higher treatment failure rate.
authors.affiliation: National Center for Tuberculosis Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Pang
authors.affiliation: National Center for Tuberculosis Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: Y-Z
authors.initials: YZ
authors.lastname: Ruan
authors.affiliation: National Center for Tuberculosis Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: J
authors.initials: J
authors.lastname: Zhao
authors.affiliation: National Center for Tuberculosis Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: C
authors.initials: C
authors.lastname: Chen
authors.affiliation: National Center for Tuberculosis Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: C-H
authors.initials: CH
authors.lastname: Xu
authors.affiliation: National Center for Tuberculosis Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: W
authors.initials: W
authors.lastname: Su
authors.affiliation: Bill & Melinda Gates Foundation, China Office, Beijing, China.
authors.forename: S-T
authors.initials: ST
authors.lastname: Huan
authors.affiliation: National Center for Tuberculosis Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: R-Z
authors.initials: RZ
authors.lastname: Li
authors.affiliation: National Center for Tuberculosis Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: Y-L
authors.initials: YL
authors.lastname: Zhao
authors.affiliation: Bill & Melinda Gates Foundation, China Office, Beijing, China.
authors.forename: D P
authors.initials: DP
authors.lastname: Chin
authors.affiliation: National Center for Tuberculosis Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: L-X
authors.initials: LX
authors.lastname: Wang
mesh_terms: D000904:Antibiotics, Antitubercular / Q000009:adverse effects / Q000627:therapeutic use*; D001431:Bacteriological Techniques; D024881:Drug Resistance, Bacterial / Q000235:genetics; D057915:Drug Substitution; D006801:Humans; D008826:Microbial Sensitivity Tests; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D020411:Oligonucleotide Array Sequence Analysis; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012293:Rifampin / Q000009:adverse effects / Q000627:therapeutic use*; D012307:Risk Factors; D013183:Sputum / Q000382:microbiology; D016896:Treatment Outcome; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis / Q000188:drug therapy* / Q000382:microbiology
chemical_list: D000904:Antibiotics, Antitubercular; D012293:Rifampin