title: Survey of drug resistance of Mycobacterium tuberculosis in 3 Mexican states, 1997.
abstract: BACKGROUND
  Drug resistance threatens global tuberculosis (TB) control efforts. Population-based estimates of drug resistance are needed to develop strategies for controlling drug-resistant TB in Mexico.
  
  
  OBJECTIVE
  To obtain population-based data on Mycobacterium tuberculosis drug resistance in Mexico.
  
  
  METHODS
  To obtain drug resistance data, we conducted a population-based study of TB cases in the states of Baja California, Sinaloa, and Oaxaca, Mexico. We performed cultures and drug susceptibility testing on M tuberculosis isolates from patients with newly diagnosed, smear-positive TB from April 1 to October 31, 1997.
  
  
  RESULTS
  Mycobacterium tuberculosis was isolated from 460 (75%) of the 614 patients. Levels of resistance in new and retreatment TB cases to 1 or more of the 3 current first-line drugs used in Mexico (isoniazid, rifampin, and pyrazinamide) were 12.9% and 50.5%, respectively; the corresponding levels of multi-drug-resistant TB were 2.4% and 22.4%. Retreatment cases were significantly more likely than new cases to have isolates resistant to 1 or more of the 3 first-line drugs (relative risk [RR], 3.9; 95% confidence interval [CI], 2.8-5.5), to have isoniazid resistance (RR, 3.6; 95% CI, 2.5-5.2), and to have multi-drug-resistant TB (RR, 9.4; 95% CI, 4.3-20.2).
  
  
  CONCLUSIONS
  This population-based study of M tuberculosis demonstrates moderately high levels of drug resistance. Important issues to consider in the national strategy to prevent M tuberculosis resistance in Mexico include consideration of the most appropriate initial therapy in patients with TB, the treatment of patients with multiple drug resistance, and surveillance or periodic surveys of resistance among new TB patients to monitor drug resistance trends.
authors.affiliation: Division of Tuberculosis Elimination, National Center for HIV, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
authors.forename: R M
authors.initials: RM
authors.lastname: Granich
authors.forename: S
authors.initials: S
authors.lastname: Balandrano
authors.forename: A J
authors.initials: AJ
authors.lastname: Santaella
authors.forename: N J
authors.initials: NJ
authors.lastname: Binkin
authors.forename: K G
authors.initials: KG
authors.lastname: Castro
authors.forename: A
authors.initials: A
authors.lastname: Marquez-Fiol
authors.forename: G
authors.initials: G
authors.lastname: Anzaldo
authors.forename: M
authors.initials: M
authors.lastname: Zarate
authors.forename: M L
authors.initials: ML
authors.lastname: Jaimes
authors.forename: O
authors.initials: O
authors.lastname: Velazquez-Monroy
authors.forename: L
authors.initials: L
authors.lastname: Salazar
authors.forename: C
authors.initials: C
authors.lastname: Alvarez-Lucas
authors.forename: P
authors.initials: P
authors.lastname: Kuri
authors.forename: A
authors.initials: A
authors.lastname: Flisser
authors.forename: J
authors.initials: J
authors.lastname: Santos-Preciado
authors.forename: C
authors.initials: C
authors.lastname: Ruiz-Matus
authors.forename: R
authors.initials: R
authors.lastname: Tapia-Conyer
authors.forename: J W
authors.initials: JW
authors.lastname: Tappero
mesh_terms: D000328:Adult; D000995:Antitubercular Agents / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D005260:Female; D006801:Humans; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000302:isolation & purification; D013183:Sputum / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000188:drug therapy*
chemical_list: D000995:Antitubercular Agents