Proportion of MDR-TB cases in Panama from 2002 to 2004. Country-wide M. tuberculosis clinical isolates were evaluated by the Canetti drug susceptibility test between 2002 and 2004. Thirty-seven isolates were multidrug-resistant (MDR). The bars show the percentage of MDR M. tuberculosis strains per year. The dotted line indicates the countrywide average proportion of TB cases with MDR-TB for the three-year period.