title: Distinct groups and antimicrobial resistance of clinical Stenotrophomonas maltophilia complex isolates from Korea.
abstract: One hundred and twenty-one isolates of Stenotrophomonas maltophilia complex were collected from seven Korean hospitals. Species and groups were identified using partial gyrB gene sequences and antimicrobial susceptibility testing was performed using a broth microdilution method. Based on partial gyrB gene sequences, 118 isolates were identified as belonging to S. maltophilia complex, including S. maltophilia, S. pavanii, Pseudomonas beteli, P. geniculata and P. hibisciola. The S. maltophilia isolates were further divided into three groups, I to III. S. maltophilia groups II and III were clustered into clade A with S. pavanii and P. beteli; S. maltophilia group I was clustered into clade B with P. geniculata and P. hibisciola. For all S. maltophilia complex isolates, the resistance rate to trimethoprim/sulfamethoxazole (TMP/SMX) was very high (30.5%). Antimicrobial resistance rates varied among species or groups of S. maltophilia complex. Isolates of clade A showed significantly lower antimicrobial resistance rates than those of clade B; while 25% of clade A isolates were multidrug resistant, 46% of clade B isolates were multidrug resistant (P=0.001). The finding of high antimicrobial resistance rates, particularly to TMP/SMX, among S. maltophilia complex isolates from Korea, and the existence of distinct groups among the isolates, with differences in antimicrobial resistance rates, suggests consideration of alternative agents to TMP/SMX to treat S. maltophilia infections and indicates the importance of accurate identification for appropriate selection of treatment options.
authors: Division of Infectious Diseases, Department of Medicine, Dankook University, Cheonan, Korea.
authors: Ji-Young
authors: JY
authors: Rhee
authors: Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon, Korea.
authors: Ji Young
authors: JY
authors: Choi
authors: Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon, Korea.
authors: Myung-Jin
authors: MJ
authors: Choi
authors: Asia Pacific Foundation for Infectious Diseases (APFID), Seoul, Korea.|Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors: Jae-Hoon
authors: JH
authors: Song
authors: Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors: Kyong Ran
authors: KR
authors: Peck
authors: Asia Pacific Foundation for Infectious Diseases (APFID), Seoul, Korea.|Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon, Korea.
authors: Kwan Soo
authors: KS
authors: Ko
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D027081:DNA Gyrase / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D024881:Drug Resistance, Bacterial; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology* / Q000382:microbiology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D010802:Phylogeny; D056910:Republic of Korea / Q000453:epidemiology; D020615:Stenotrophomonas maltophilia / Q000145:classification* / Q000187:drug effects*
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D027081:DNA Gyrase