Surveillance of Mycobacterium tuberculosis susceptibility to second-line drugs in Hong Kong, 1995-2002, after the implementation of DOTS-plus

Int J Tuberc Lung Dis. 2004 Jun;8(6):760-6.

Abstract

Objective: To determine the trend in changes in susceptibility of Mycobacterium tuberculosis strains, including to second-line drugs, from patients with a history of previous anti-tuberculosis (TB) treatment in a 'DOTS-Plus' programme.

Methods: A retrospective survey of centralised M. tuberculosis laboratory records of all culture-positive cases over an 8-year period. The drug susceptibility of the isolates was determined using the absolute concentration method. Isolates obtained from patients with a history of previous treatment were further analysed for trends of changes in susceptibility to first- and second-line drugs.

Results: Of 1921 patients with a previous history of treatment and positive cultures, 1425 (74.2%) had isolates susceptible to all four first-line drugs, while 176 (9.2%) were multidrug-resistant (MDR-TB). For the MDR-TB group, 101 (57.4%) isolates were sensitive to all second-line drugs, while 30 (17.0%) were resistant to three or more second-line drugs.

Conclusion: In a DOTS-Plus programme environment where there is strict control on use of second-line drugs, the prevalence of MDR-TB is low amongst retreatment cases and the prudent use of second-line drugs in a population with well functioning DOTS-Plus programme does not generate super-resistant strains. In circumstances where most retreatment strains are still susceptible and good laboratory support for detection of MDR cases is available, retreatment using first-line drugs is feasible.

MeSH terms

  • Amikacin / administration & dosage*
  • Amikacin / pharmacology
  • Amikacin / therapeutic use
  • Anti-Bacterial Agents / administration & dosage*
  • Anti-Bacterial Agents / pharmacology
  • Anti-Bacterial Agents / therapeutic use
  • Antitubercular Agents / administration & dosage*
  • Antitubercular Agents / pharmacology
  • Antitubercular Agents / therapeutic use
  • Communicable Disease Control / methods
  • Cycloserine / administration & dosage*
  • Cycloserine / pharmacology
  • Cycloserine / therapeutic use
  • Directly Observed Therapy
  • Drug Combinations
  • Ethionamide / administration & dosage*
  • Ethionamide / pharmacology
  • Ethionamide / therapeutic use
  • Hong Kong / epidemiology
  • Humans
  • Microbial Sensitivity Tests
  • Mycobacterium tuberculosis / drug effects*
  • Mycobacterium tuberculosis / isolation & purification
  • Ofloxacin / administration & dosage*
  • Ofloxacin / pharmacology
  • Ofloxacin / therapeutic use
  • Population Surveillance
  • Program Evaluation
  • Recurrence
  • Tuberculosis, Multidrug-Resistant / drug therapy*
  • Tuberculosis, Multidrug-Resistant / epidemiology
  • Tuberculosis, Pulmonary / drug therapy*
  • Tuberculosis, Pulmonary / pathology

Substances

  • Anti-Bacterial Agents
  • Antitubercular Agents
  • Drug Combinations
  • Amikacin
  • Cycloserine
  • Ofloxacin
  • Ethionamide