title: Primary drug resistance to anti-tuberculous drugs in Karachi.
abstract: OBJECTIVE
  To assess the frequency of primary drug resistance among newly diagnosed tuberculosis cases in Karachi.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Multicentric study involving various TB clinics and treatment centres of Karachi between April to December 2005.
  
  
  METHODS
  The frequency of drug resistance among new TB patients was evaluated using a non-probability convenient sampling methodology. Sputum sample was obtained from 140 newly diagnosed sputum smear-positive patients of pulmonary tuberculosis from various centres of Karachi. Sensitivities were performed by proportion method.
  
  
  RESULTS
  Fifteen (11.5%) samples in 130 eligible patients showed primary resistance to one or more drugs. Ten (7.6%) of the isolates tested were resistant to a single drug, none were resistant to 2 drugs, 4 (3.0%) to 3 drugs and 1 (0.76%) to 4 drugs while 1 (0.76%) to all 5 first line agents. Resistance to streptomycin (10 microg/ml) was seen in 8 (6.1%), isoniazid (1microg/ml) in 12 (9.2%), Rifampicin (5 microg/ml) in 4 (3.0%), ethambutol (10 microg/ml) in 1 (0.76%) and pyrazinamide in 6 (4.6%) samples. Primary Multi-Drug Resistance (PMDR) was found in 2 (1.5%) patients. (Isoniazid 1 microg/ml, rifampicin 5 microg/ml with or without other drugs).
  
  
  CONCLUSIONS
  In the studied patients, primary drug resistance to at least one anti-tuberculosis drug was 11.5%. It requires an efficiently working anti-tuberculosis programme to prevent escalation including resistance.
authors.affiliation: Department of Pulmonology, Postgraduate Medical Institute, Peshawar. arshadj343@hotmail.com
authors.forename: Arshad
authors.initials: A
authors.lastname: Javaid
authors.forename: Nadim
authors.initials: N
authors.lastname: Rizvi
authors.forename: Mosavir
authors.initials: M
authors.lastname: Ansari
authors.forename: Ashraf
authors.initials: A
authors.lastname: Sadiq
authors.forename: Iqbal Sher
authors.initials: IS
authors.lastname: Burki
authors.forename: Nadeem Ur
authors.initials: NU
authors.lastname: Rehman
authors.forename: Rumina
authors.initials: R
authors.lastname: Hasan
authors.forename: Afia
authors.initials: A
authors.lastname: Zafar
mesh_terms: D000995:Antitubercular Agents / Q000627:therapeutic use*; D003430:Cross-Sectional Studies; D004198:Disease Susceptibility; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects*; D006801:Humans; D009169:Mycobacterium tuberculosis / Q000187:drug effects*; D010154:Pakistan; D018088:Tuberculosis, Multidrug-Resistant / Q000188:drug therapy*; D014397:Tuberculosis, Pulmonary / Q000188:drug therapy*
chemical_list: D000995:Antitubercular Agents