title: Increasing drug resistance of Mycobacterium tuberculosis in Sinaloa, Mexico, 1997-2005.
abstract: BACKGROUND
  In 1997 the US Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) reported high proportions of drug-resistant Mycobacterium tuberculosis in three Mexican states: Sinaloa, Baja California, and Oaxaca. In 2006, we showed that resistance to anti-tuberculosis drugs remained frequent in Sinaloa.
  
  
  OBJECTIVE
  The objectives of this study were to describe drug-resistant tuberculosis (TB) trends and to investigate the probability that patients acquire resistance to first-line anti-TB drugs on recurrence after treatment in Sinaloa.
  
  
  METHODS
  Sputum specimens were collected from patients diagnosed with TB at all the health care institutions of Sinaloa during 1997-2005. Isolates were tested for susceptibility to first-line drugs.
  
  
  RESULTS
  Among 671 isolates tested from 1997 to 2002, the overall resistance rate was 34.9% (95% confidence interval (CI) 31.2-38.4) with a 1.2% increase per year (Chi-square=4.258, p=0.03906). The prevalence of multi-drug resistance (MDR) was 17.9% (95% CI 14.9-20.7) with a 1.2% increase per year (Chi-square=8.352, p=0.00385). Of 50 patients registered twice between 1997 and 2005, 15 were fully susceptible at first registration, of whom six (40%) acquired drug resistance. Of 35 cases with any drug resistance at first registration, 21 (60%) came to acquire resistance to at least one other drug.
  
  
  CONCLUSIONS
  The proportion of drug-resistant TB increased during 1997-2005 in Sinaloa. Major efforts are needed to prevent the further rise and spread of drug-resistant and MDR TB.
authors.affiliation: Programa Regional Para el Doctorado en Biotecnología, FCQB-UAS, Culiacán, Sinaloa, Mexico.
authors.forename: Jorge
authors.initials: J
authors.lastname: Zazueta-Beltran
authors.forename: Nidia
authors.initials: N
authors.lastname: León-Sicairos
authors.forename: Secundino
authors.initials: S
authors.lastname: Muro-Amador
authors.forename: Adrian
authors.initials: A
authors.lastname: Flores-Gaxiola
authors.forename: Jorge
authors.initials: J
authors.lastname: Velazquez-Roman
authors.forename: Hector
authors.initials: H
authors.lastname: Flores-Villaseñor
authors.forename: Adrian
authors.initials: A
authors.lastname: Canizalez-Roman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000995:Antitubercular Agents / Q000494:pharmacology*; D002648:Child; D024881:Drug Resistance, Bacterial; 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; D018088:Tuberculosis, Multidrug-Resistant / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D055815:Young Adult
chemical_list: D000995:Antitubercular Agents