Drug resistance in Mycobacterium tuberculosis strains isolated from re-treatment cases of pulmonary tuberculosis in Ethiopia: susceptibility to first-line and alternative drugs.
METHODS
Addis Ababa Tuberculosis Demonstration and Training Center, Ethiopia.


OBJECTIVE
To determine the pattern of drug resistance among re-treatment cases of pulmonary tuberculosis (TB), to determine the risk factors associated with multi-drug resistant (MDR) TB, and to propose re-treatment regimens based on the patterns of susceptibility to first-line and alternative drugs.


METHODS
One hundred and seven Mycobacterium tuberculosis strains isolated from an equal number of re-treatment cases of pulmonary TB were included in the study. Drug susceptibility was determined by the Bactec method.


RESULTS
About 50% of the strains were resistant to one or more of the first-line drugs and 12% of the strains were multi-drug resistant, i.e., resistant to both isoniazid and rifampicin. Previous treatment with rifampicin was the most important predictor of MDR-TB. All MDR strains were susceptible to amikacin, ciprofloxacin, ethambutol, ethionamide and clofazimine.


CONCLUSIONS
The WHO re-treatment regimen would theoretically be effective for the treatment of all non-MDR-TB patients in this study. A proposed 12-month re-treatment regimen for MDR-TB patients would include a fluoroquinolone in combination with streptomycin, pyrazinamide, isoniazid, ethambutol and clofazimine. There is an urgent need for more research to define safe and inexpensive treatment regimens for MDR-TB patients in low-income countries.
Abate
G
G
Department of Microbiology and Parasitology, Addis Ababa University, Ethiopia.
Miörner
H
H
Ahmed
O
O
Hoffner
S E
SE
D000293:Adolescent; D000328:Adult; D000995:Antitubercular Agents / Q000494:pharmacology*; D005002:Ethiopia / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000187:drug effects*; D012307:Risk Factors; D018088:Tuberculosis, Multidrug-Resistant / Q000188:drug therapy / Q000453:epidemiology*
D000995:Antitubercular Agents