RESUMO
OBJECTIVE: To determine the rate and type of anti-tuberculosis drug resistance at King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia. DESIGN: Review of microbiology and infection control databases for all patients with culture-positive Mycobacterium tuberculosis between June 1981 and May 2003 at the hospital. BACTEC 460TB radiometry then MGIT 960 were used for both mycobacterial detection and antimicrobial susceptibility testing. RESULTS: A total of 764 M. tuberculosis isolates were obtained from 764 patients. Resistance to first-line agents (isoniazid, rifampicin, ethambutol and streptomycin) was noted in 65 (8.5%). Resistance to isoniazid was the highest, noted in 54 (7.1%); resistance to rifampicin, streptomycin and ethambutol was found in respectively 21 (2.7%), 29 (3.8%) and 12 (1.6%) isolates. Polyresistance was noted in eight (1%) isolates and monoresistance in 38 (5%) isolates. Multidrug-resistant M. tuberculosis was found in 19 (2.5%) isolates. There were 54 primary resistant isolates (7.6%), and 11 (22%) with acquired resistance. The median age of patients with resistant isolates was 38 years compared to 48 years for patients with sensitive isolates (P = 0.002). CONCLUSION: Resistance to first-line anti-tuberculosis agents and multidrug-resistant M. tuberculosis remain relatively low in Saudi Arabia.
