DRUG-RESISTANCE AMONG MYCOBACTERIUM-TUBERCULOSIS ISOLATES IN LEBANON

OBJECTIVE: To determine the prevalence and patterns of drug resistance among Mycobacterium tuberculosis isolates recovered from tuberculosis (TB) cases in Lebanon. DESIGN: A total of 96 isolates were collected from the same number of TB cases between October 1994 and December 199 5. These isolates were obtained from cases with newly diagnosed (81.3% ) and previously treated (18.7%) cases of TB, and tested against isoni azid (INH), rifampicin (RIF), streptomycin (STM) and ethambutol (ETH), using the BACTEC-TB susceptibility procedure and system. RESULTS: The male to female ratio was 2:1 and the mean ages of males and females w ere almost similar, 34.1 and 32.7 years, respectively. Resistance to o ne or more drugs was found in 25 of 96 (26%) isolates. The overall per centages of single drug resistance against INH, RIF, STM and ETH were 23.9%, 12.5%, 7.3% and 3.1%, respectively. These percentages were high er, for all drugs, in isolates recovered from previously treated compa red to new cases of TB: INH (50% vs 17.9%), RIF (33.3% vs 7.7%), STM ( 22.2% vs 3.8%) and ETH (11.1% vs 1.3%). Of the 25 resistant isolates, 11 were resistant to one drug only (10 to INH and 1 to STM), 10 were r esistant to two drugs (7 to INH and RIF, 2 to INH and STM, 1 to STM an d RIF), 2 were resistant to three drugs (1 to INH, RIF and ETH, 1 to I NH, RIF and STM) and 2 were resistant to the four tested drugs. CONCLU SION: These data show that M. tuberculosis isolates in Lebanon have hi gh rates of single and multidrug resistance, and speaks for the need t o establish surveillance and monitoring programs in this country as pa rt of the global effort to control TB.