Treatment outcomes and long-term survival in patients with extensively drug-resistant tuberculosis.
BACKGROUND
The increasing worldwide incidence of extensively drug-resistant tuberculosis (XDR-TB) has emerged as a threat to public health and tuberculosis (TB) control. Treatment outcomes have varied among studies, and data on long-term survival are still scarce.


OBJECTIVE
To retrospectively assess the burden, clinical characteristics, treatment outcomes, and long-term survival rate of patients with XDR-TB in a cohort of patients with HIV-negative multidrug-resistant tuberculosis (MDR-TB) in South Korea.


METHODS
Medical records were reviewed of patients newly diagnosed with or retreated for MDR-TB from 2000 to 2002. The cohort was monitored for 3 to 7 years after the initiation of treatment. Initial treatment outcomes and cumulative survival rates were analyzed, and predictors of treatment success and survival were defined.


RESULTS
Of 1,407 patients with MDR-TB 75 (5.3%) had XDR-TB at treatment initiation. The default rate was high (453/1,407; 32%), and patients with XDR-TB had lower treatment success (29.3 vs. 46.2%; P = 0.004) and higher all-cause (49.3 vs. 19.4%; P < 0.001) and TB-related disease mortality (41.3 vs. 11.8%; P < 0.001) than other patients with MDR-TB. The presence of XDR-TB significantly affected treatment success (odds ratio, 0.23; 95% confidence interval [CI], 0.08-0.64; P = 0.005), all-cause mortality (hazards ratio, 3.25; 95% CI, 1.91-5.53; P < 0.001), and TB-related mortality (hazards ratio, 4.45; 95% CI, 2.48-8.00; P < 0.001) on multivariate analyses.


CONCLUSIONS
XDR-TB occurred in a substantial proportion of patients with MDR-TB in South Korea, and was the strongest predictor of treatment outcomes and long-term survival in patients with MDR-TB. Adequate TB control policies should be implemented to prevent the further development and spread of drug resistance.
Kim
Doh Hyung
DH
Department of Internal Medicine, Dankook University College of Medicine, Dankook University Hospital, Cheonan, South Korea.
Kim
Hee Jin
HJ
Park
Seung-Kyu
SK
Kong
Suck-Jun
SJ
Kim
Young Sam
YS
Kim
Tae-Hyung
TH
Kim
Eun Kyung
EK
Lee
Ki Man
KM
Lee
Sung Soon
SS
Park
Jae Seuk
JS
Koh
Won-Jung
WJ
Lee
Chang-Hoon
CH
Kim
Ji Yeon
JY
Shim
Tae Sun
TS
D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D015331:Cohort Studies; D004359:Drug Therapy, Combination; D054908:Extensively Drug-Resistant Tuberculosis / Q000188:drug therapy* / Q000601:surgery; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D007723:Korea; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D012189:Retrospective Studies; D055502:Secondary Prevention
D000900:Anti-Bacterial Agents