Susceptibility pattern and epidemiology of Mycobacterium tuberculosis in a Saudi Arabian hospital: a 15-year study from 1989 to 2003.

OBJECTIVES The objective of this study was to examine the prevalence and trends of drug resistance of Mycobacterium tuberculosis at the Saudi Aramco Medical Services Organization. METHODS We retrospectively identified M tuberculosis isolates from January 1989 to December 2003. Antimicrobial susceptibility and clinical data were collected and analyzed. RESULTS From 1989 to 2003, 276 nonrepetitive culture-positive cases were identified. There were 236 Saudis (84.6%), and the remainder were non-Saudis (15.4%). M tuberculosis isolates were obtained from pulmonary specimens (49%) and extrapulmonary sites (51%). The resistance rates of M tuberculosis to tested first-line agents were as follows: isoniazid, 12.5%; ethambutol, 7.5%; streptomycin; 6.9%; and rifampin, 1.1%. The resistance rate to isoniazid and streptomycin was 1.8%, the rate to isoniazid and rifampin was 0.7%, and the rate to isoniazid and ethambutol was 2.5%. The resistance rate to isoniazid, ethambutol, and streptomycin was 0.7% CONCLUSION M tuberculosis resistance to isoniazid showed a decreased rate over the study period from 20 to 5.7%. The rate of multidrug-resistant M tuberculosis remained low.