National antimicrobial resistance surveillance among clinical isolates of Streptococcus pneumoniae in Thailand.

As part of the continuing national antimicrobial surveillance, the national antimicrobial resistance surveillance thailand (NARST), data of all clinical isolates of Streptococcus pneumoniae were collected from 28 hospitals in Thailand from 2000 to 2005. Epidemiological and microbiological data were obtained and analyzed using the WHONET software program. Among all isolates tested for antimicrobial susceptibility, the rates of penicillin resistance were constantly high, ranging from 42.4% in 2000 to 47.7% in 2005. The third-generation cephalosporin resistance rate, determined by Epsilon test (E-test) in 10% to 15% of all isolates each year, ranged from 2.1% to 8.4%. The rates of erythromycin resistance ranged from 24.2% to 30.3%. Surprisingly, one isolate in 2005 was resistant to levofloxacin. The rates of multi-drug resistance ranged from 14.8% to 34.3%. In conclusion; the present (NARST) study documents remarkable increase of penicillin, erythromycin, and multi-drug resistance rates in Thailand, especially among isolates from the North, the Center, the East, and Bangkok; from university hospitals; from young children; and from non-sterile specimens.