Abstract
In this study the drug resistance pattern of 3559 Mycobacterium tuberculosis strains isolated in Austria between 1995 and 98 was evaluated. Of these strains, 165 (4.6%) were resistant to one or more drugs, 113 (3.2%) to one of the tested drugs and 53 (1.5%) to two or more drugs. Monodrug resistance was observed most often to isoniazid (56 strains), followed by streptomycin (44 strains). Resistance to rifampicin or ethambutol alone was rarely seen (12 strains and 1 strain, respectively). Of the 53 strains resistant to 2 or more drugs, 25 were resistant to isoniazid and streptomycin, while 17 were multidrug resistant. Molecular typing revealed a large diversity among the multidrug-resistant strains.