The National Antimicrobial Resistance Surveillance Thailand (NARST) has been initiated since
1998 to strengthen the surveillance program for antimicrobial-resistant pathogens as well as to standardize
the laboratory practices in Thailand. This collaborative network was funded by the World Health Organization,
and involved 33 hospitals throughout Thailand at the first phase. Nevertheless, no prior effort has been made
to share the antimicrobial resistance data in the national level. In this overview, the authors provide an
update on the status of antimicrobial resistance from 2000 to 2005 among important Gram-negative pathogens
as well as the implication of these findings. The most striking finding appears to be the emergence of
pandrug-resistant (PDR) Acinetobacter baumannii. Carbapenem-resistant A. baumannii has been dramatically
increasing from 2.1% in 2000 to 46.7% in 2005. There is a trend towards the increasing incidence rates of
ESBL-producing Escherichia coli from 2000 to 2005, but the incidence rates of ESBL-producing Klebseilla
pneumoniae remain constant during the same period. The susceptibility of Burkholderia pseudomallei to
various antibiotics, particularly ceftazidime and carbapenems, approached 100%.

In conclusions, to help strengthen the future surveillance system, NARST needs to develop the
data collection tools that include some important patient characteristics and the information that can help
distinguish colonizations and infections as well as community-acquired infections and hospital-acquired
infections. In addition, an appropriate test for antimicrobial susceptibility including the minimal inhibitory
concentration determination should be implemented and carried out for all important pathogens. The NARST
data emphasized a need to strengthen the antimicrobial stewardship as well as the infection control measures
at the hospital level to help reduce the transmission of antimicrobial-resistant Gram-negative bacteria in
Thailand.

Keywords: Anti-infective agents, Drug resistance, Bacterial, Gram-negative bacteria, Microbial sensitivity
tests, Population surveillance, Thailand