Primary drug resistance patterns in newly diagnosed tuberculosis patients in Yazd, Southern Province of Iran

Prevalence of multidrug resistant (MDR) and extensively drug-resistant tuberculosis (XDR) has been a cause of concern for tuberculosis (TB) control in both developed and developing countries. The objective of this study was to investigate the prevalence of drug resistance patterns among newly diagnosed tuberculosis cases, in Yazd, the southern province of Iran, during 2009 to 2010. The drug susceptibility testing (DST) was performed for 31 culture-positive individuals. The strains that were identified as MDR were subjected to susceptibility testing for second line drugs. The highest rate of resistance was to ethinoamide (51.61%), followed by kanamycin (29.03%), streptomycin (25.8%), rifampine (22.58%), isoniazid (6.45%), and ethambutol (3.2%). Drug resistance to both isoniazid and rifampin was identified in 2 cases.