Trend of anti-tuberculosis drug resistance in Korea, 1994-2004.

SETTING

The 245 health centres through which the National Tuberculosis Programme (NTP) is implemented in Korea and the TB Laboratory Network of the Korean National Tuberculosis Association.

OBJECTIVE

To observe the trend of anti-tuberculosis drug resistance in Korea from 1994 to 2004 and possible related factors.

DESIGN

All tuberculosis (TB) patients registered for treatment at the health centres for a given period were assessed.

RESULTS

Of 2636 new smear-positive patients from the 2004 survey, 338 cases (12.8%, 95% confidence interval [CI] 11.5-14.1) showed resistance to any of the first-line drugs: 261 with isoniazid (INH) resistance (9.9%, 95%CI 8.8-11.0) and 71 with multidrug resistance (MDR) (2.7%, 95%CI 2.1-3.3). Compared with previous surveys, a statistically significant increase in MDR (P=0.00675), any drug resistance (P=0.03779), any INH resistance (P=0.00313) and any rifampicin resistance (P = 0.00176) has been observed among new cases since 1994. Any resistance to second-line drugs ranged from 0.1% (capreomycin) to 1.1% (para-aminosalicylic acid) among new cases and from 1.1% to 3.6% among retreatment cases. Resistance to kanamycin and ofloxacin was found in 1.4% and 2.6%, respectively, of new and previously treated MDR-TB cases.

CONCLUSION

A statistically significant increase in drug resistance was noticed among new cases.