title: Performance Comparison of Three Rapid Tests for the Diagnosis of Drug-Resistant Tuberculosis.
abstract: BACKGROUND
  The aim of this study was to compare the performance of several recently developed assays for the detection of multi- and extensively drug-resistant tuberculosis (M/XDR-TB) in a large, multinational field trial.
  
  
  METHODS
  Samples from 1,128 M/XDR-TB suspects were examined by Line Probe Assay (LPA), Pyrosequencing (PSQ), and Microscopic Observation of Drug Susceptibility (MODS) and compared to the BACTEC MGIT960 reference standard to detect M/XDR-TB directly from patient sputum samples collected at TB clinics in India, Moldova, and South Africa.
  
  
  RESULTS
  Specificity for all three assays was excellent: 97-100% for isoniazid (INH), rifampin (RIF), moxifloxacin (MOX) and ofloxacin (OFX) and 99-100% for amikacin (AMK), capreomycin (CAP) and kanamycin (KAN) resistance. Sensitivities were lower, but still very good: 94-100% for INH, RIF, MOX and OFX, and 84-90% for AMK and CAP, but only 48-62% for KAN. In terms of agreement, statistically significant differences were only found for detection of RIF (MODS outperformed PSQ) and KAN (MODS outperformed LPA and PSQ) resistance. Mean time-to-result was 1.1 days for LPA and PSQ, 14.3 days for MODS, and 24.7 days for MGIT.
  
  
  CONCLUSIONS
  All three rapid assays evaluated provide clinicians with timely detection of resistance to the drugs tested; with molecular results available one day following laboratory receipt of samples. In particular, the very high specificity seen for detection of drug resistance means that clinicians can use the results of these rapid tests to avoid the use of toxic drugs to which the infecting organism is resistant and develop treatment regiments that have a higher likelihood of yielding a successful outcome.
authors: University of California San Diego, La Jolla, California, United States of America.
authors: Antonino
authors: A
authors: Catanzaro
authors: University of California San Diego, La Jolla, California, United States of America.
authors: Timothy C
authors: TC
authors: Rodwell
authors: University of Arkansas, Fayetteville, Arkansas, United States of America.
authors: Donald G
authors: DG
authors: Catanzaro
authors: University of California San Diego, La Jolla, California, United States of America.
authors: Richard S
authors: RS
authors: Garfein
authors: University of California San Diego, La Jolla, California, United States of America.
authors: Roberta L
authors: RL
authors: Jackson
authors: University of California San Diego, La Jolla, California, United States of America.
authors: Marva
authors: M
authors: Seifert
authors: University of California San Diego, La Jolla, California, United States of America.
authors: Sophia B
authors: SB
authors: Georghiou
authors: Stellenbosch University, Stellenbosch, South Africa.
authors: Andre
authors: A
authors: Trollip
authors: University of California San Diego, La Jolla, California, United States of America.
authors: Erik
authors: E
authors: Groessl
authors: University of California San Diego, La Jolla, California, United States of America.
authors: Naomi
authors: N
authors: Hillery
authors: Institute of Phthisiopneumology, Chisinau, Moldova.
authors: Valeriu
authors: V
authors: Crudu
authors: Stellenbosch University, Stellenbosch, South Africa.
authors: Thomas C
authors: TC
authors: Victor
authors: PD Hinduja Hospital and Medical Research Centre, Mumbai, India.
authors: Camilla
authors: C
authors: Rodrigues
authors: Microbial Diseases Laboratory, California Department of Public Health, Richmond, California, United States of America.
authors: Grace Shou-Yean
authors: GS
authors: Lin
authors: San Diego State University, San Diego, California, United States of America.
authors: Faramarz
authors: F
authors: Valafar
authors: Microbial Diseases Laboratory, California Department of Public Health, Richmond, California, United States of America.
authors: Edward
authors: E
authors: Desmond
authors: University of Arkansas, Little Rock, Arkansas, United States of America.
authors: Kathleen
authors: K
authors: Eisenach
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000995:Antitubercular Agents / Q000627:therapeutic use; D002648:Child; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects; D054908:Extensively Drug-Resistant Tuberculosis / Q000175:diagnosis* / Q000188:drug therapy; D005260:Female; D006801:Humans; D007194:India; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D008966:Moldova; D009169:Mycobacterium tuberculosis / Q000187:drug effects; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013019:South Africa; D018088:Tuberculosis, Multidrug-Resistant / Q000175:diagnosis* / Q000188:drug therapy; D055815:Young Adult
chemical_list: D000995:Antitubercular Agents