title: Cost-effectiveness of the Xpert® MTB/RIF assay for tuberculosis diagnosis in Brazil.
abstract: BACKGROUND
  The Xpert® MTB/RIF assay is being implemented as a substitute for sputum smear microscopy (SSM) in many low and high tuberculosis (TB) burden countries, including Brazil, a country with low multidrug resistance and moderate human immunodeficiency virus co-infection rates.
  
  
  METHODS
  Brazilian National TB Programme (NTP).
  
  
  OBJECTIVE
  We estimated the incremental cost-effectiveness ratio (ICER) of Xpert as a substitute for two SSM tests in the diagnosis of drug-susceptible TB. The costs for confirming each additional case and for avoiding treatment due to false-positive empirical diagnoses were estimated.
  
  
  RESULTS
  The ICER was US$943 for each additional TB diagnosis and US$356 for each additional TB diagnosis with bacteriological confirmation, assuming 80% specificity of clinical diagnosis using both strategies. For every 100 000 patients with suspected TB, the NTP would spend an additional US$1.2 million per year to confirm 3344 more TB patients. The model was highly sensitive to specificity of clinical diagnosis after a negative test.
  
  
  CONCLUSIONS
  Although the NTP has no threshold for cost-effectiveness, our model can provide support for decision makers in Brazil and other countries with a low prevalence of drug resistance among TB patients. Financial benefit can potentially be expected if physicians rely more on a negative Xpert result and empirical treatment is reduced.
authors.affiliation: Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
authors.forename: M
authors.initials: M
authors.lastname: Pinto
authors.affiliation: Rio de Janeiro Federal University, Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: R E
authors.initials: RE
authors.lastname: Steffen
authors.affiliation: KNCV Tuberculosis Foundation, The Hague, The Netherlands; Department of Global Health, Academic Medical Center, and Amsterdam Institute for Global Health and Development, Amsterdam, The Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Cobelens
authors.affiliation: KNCV Tuberculosis Foundation, The Hague, The Netherlands; Department of Global Health, Academic Medical Center, and Amsterdam Institute for Global Health and Development, Amsterdam, The Netherlands.
authors.forename: S
authors.initials: S
authors.lastname: van den Hof
authors.affiliation: Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
authors.forename: A
authors.initials: A
authors.lastname: Entringer
authors.affiliation: Rio de Janeiro Federal University, Rio de Janeiro, Rio de Janeiro, Brazil, McGill University, Montréal, Quebec, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Trajman
mesh_terms: D000904:Antibiotics, Antitubercular / Q000627:therapeutic use; D057205:Automation, Laboratory; D001938:Brazil; D003198:Computer Simulation; D003362:Cost-Benefit Analysis; D004269:DNA, Bacterial / Q000235:genetics* / Q000302:isolation & purification; D003661:Decision Support Techniques; D003663:Decision Trees; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D005189:False Positive Reactions; D017048:Health Care Costs; D006801:Humans; D008168:Lung / Q000382:microbiology*; D025202:Molecular Diagnostic Techniques / Q000191:economics*; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D016133:Polymerase Chain Reaction / Q000191:economics*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012293:Rifampin / Q000627:therapeutic use; D013183:Sputum / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000188:drug therapy / Q000191:economics* / Q000382:microbiology; D019564:Unnecessary Procedures / Q000191:economics
chemical_list: D000904:Antibiotics, Antitubercular; D004269:DNA, Bacterial; D012293:Rifampin