title: Feasibility of decentralised deployment of Xpert MTB/RIF test at lower level of health system in India.
abstract: BACKGROUND
  Xpert MTB/RIF is an automated cartridge-based nucleic acid amplification test that has demonstrated its potential to detect tuberculosis and rifampicin resistance with high accuracy. To assist scale-up decisions in India, a feasibility assessment of Xpert MTB/RIF implementation was conducted within microscopy centres of 18 RNTCP TB units.
  
  
  METHODS
  As part of programme-based demonstration of Xpert MTB/RIF implementation, we recorded and analysed association between key implementation factors and the ability of test to produce valid results. Factors contributing to test failures were analysed from GeneXpert software data which provides 'failure codes' and causes for test failures.
  
  
  RESULTS
  From March'12 to January'13, total 40,035 suspects were tested by Xpert MTB/RIF, and 39,680 (99.1%) received valid results (Cumulative: 37157 (92.8%) on first attempt, 39410 (98.4%) on second attempt, 39637 (99.0%) on third attempt and 39680 (99.1%) on more attempts). Overall initial test failure was 2,878 (7.2% (4%-17%)); of these, 2,594 (90.1%) were re-tested and produced valid results. Most frequent reason of test failure was inadequate sample processing or equipment malfunction (3.9%). Other reasons included power failure (1.1%), cartridge integrity/component failure (0.8%), device-computer communication error (0.5%), and temperature-related errors (0.08%). Significant variation was observed in failure rates both across instruments and over time; furthermore, substantial variation was observed in failure rate in two cartridges lots.
  
  
  CONCLUSIONS
  Installation required minimal infrastructure modifications and concerns about adequacy of human resources under public sector facilities and temperature extremes proved unfounded. Under routine conditions, Xpert MTB/RIF provided 99.1% valid results in TB suspects with low overall failure rates (7.2% initial failure, 0.9% final failure); devices provided valuable real-time feedback on reasons for test failure, which were used for rapid corrective action. High modular replacement (32%) and inter-lot cartridge performance variation remain sources of concern, and warrant close monitoring of failure rates as a key quality indicator.
authors.affiliation: Foundation for Innovative New Diagnostics, New Delhi, India.
authors.forename: Neeraj
authors.initials: N
authors.lastname: Raizada
authors.affiliation: Central TB Division, Government of India, New Delhi, India.
authors.forename: K S
authors.initials: KS
authors.lastname: Sachdeva
authors.affiliation: World Health Organization, India Country Office, New Delhi, India.
authors.forename: Achuthan
authors.initials: A
authors.lastname: Sreenivas
authors.affiliation: Foundation for Innovative New Diagnostics, New Delhi, India.
authors.forename: Bhavin
authors.initials: B
authors.lastname: Vadera
authors.affiliation: Central TB Division, Government of India, New Delhi, India.
authors.forename: R S
authors.initials: RS
authors.lastname: Gupta
authors.affiliation: World Health Organization, India Country Office, New Delhi, India.
authors.forename: Malik
authors.initials: M
authors.lastname: Parmar
authors.affiliation: Foundation for Innovative New Diagnostics, New Delhi, India.
authors.forename: Shubhangi
authors.initials: S
authors.lastname: Kulsange
authors.affiliation: Foundation for Innovative New Diagnostics, New Delhi, India.
authors.forename: Ameet
authors.initials: A
authors.lastname: Babre
authors.affiliation: Foundation for Innovative New Diagnostics, New Delhi, India.
authors.forename: Rahul
authors.initials: R
authors.lastname: Thakur
authors.affiliation: Foundation for Innovative New Diagnostics, Geneva, Switzerland.
authors.forename: Christen
authors.initials: C
authors.lastname: Gray
authors.affiliation: World Health Organization, India Country Office, New Delhi, India.
authors.forename: Ranjani
authors.initials: R
authors.lastname: Ramachandran
authors.affiliation: Foundation for Innovative New Diagnostics, New Delhi, India.
authors.forename: Umesh
authors.initials: U
authors.lastname: Alavadi
authors.affiliation: World Health Organization, India Country Office, New Delhi, India.
authors.forename: Mayank
authors.initials: M
authors.lastname: Ghedia
authors.affiliation: Foundation for Innovative New Diagnostics, New Delhi, India.
authors.forename: Balasangameshwara
authors.initials: B
authors.lastname: Vollepore
authors.affiliation: World Health Organization, India Country Office, New Delhi, India.
authors.forename: Puneet
authors.initials: P
authors.lastname: Dewan
authors.affiliation: Foundation for Innovative New Diagnostics, Geneva, Switzerland.
authors.forename: Catharina
authors.initials: C
authors.lastname: Boehme
authors.affiliation: Foundation for Innovative New Diagnostics, New Delhi, India.
authors.forename: C N
authors.initials: CN
authors.lastname: Paramsivan
mesh_terms: D003695:Delivery of Health Care / Q000458:organization & administration*; D005240:Feasibility Studies; D006297:Health Services Accessibility; D006801:Humans; D007194:India; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000235:genetics; D009696:Nucleic Acids / Q000235:genetics*; D012293:Rifampin / Q000494:pharmacology* / Q000627:therapeutic use; D018088:Tuberculosis, Multidrug-Resistant / Q000175:diagnosis* / Q000188:drug therapy
chemical_list: D009696:Nucleic Acids; D012293:Rifampin