title: CTX-M-producing Salmonella spp. in Hong Kong: an emerging problem.
abstract: Two Salmonella enterica serovar Typhimurium isolates and one S. enterica serovar Enteritidis isolate that were resistant to 4 microg cefotaxime ml-1 and produced CTX-M-type extended-spectrum beta-lactamases (ESBLs) were characterized from patients in Hong Kong during 2003-2004. The S. Typhimurium strain isolated in 2003 produced a CTX-M-9 ESBL and harboured a blaCTX-M-9 gene that was associated with a class I integron-containing gene cassette and orf513 similar to those of In60. The second S. Typhimurium strain and the S. Enteritidis strain, both isolated in 2004, produced CTX-M-14; the former also produced TEM-1. The blaCTX-M-14 gene in these two isolates was associated with the insertion sequence ISEcp1. The CTX-M genes were present on a transferable plasmid of 62, 70 or 92 kb. PFGE of XbaI-restricted total DNA from the two S. Typhimurium isolates indicated that they were not clonally related. These three isolates were also resistant to one of the other non-beta-lactam antimicrobial agents tested. This is the first report of a CTX-M-9 ESBL in Salmonella in Hong Kong and the presence of blaCTX-M-9 and blaCTX-M-14 in S. Typhimurium.
authors.affiliation: Department of Microbiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China.
authors.forename: Yujuan
authors.initials: Y
authors.lastname: Jin
authors.affiliation: Department of Microbiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China.
authors.forename: J M
authors.initials: JM
authors.lastname: Ling
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015373:Bacterial Typing Techniques; D002439:Cefotaxime / Q000494:pharmacology; D002675:Child, Preschool; D016172:DNA Fingerprinting; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000235:genetics; D015252:Deoxyribonucleases, Type II Site-Specific / Q000378:metabolism; D016521:Electrophoresis, Gel, Pulsed-Field; D029968:Escherichia coli Proteins / Q000096:biosynthesis* / Q000235:genetics; D005798:Genes, Bacterial; D006723:Hong Kong; D006801:Humans; D032023:Integrons / Q000235:genetics; D016366:Open Reading Frames; D010957:Plasmids / Q000235:genetics; D012480:Salmonella Infections / Q000382:microbiology*; D012477:Salmonella enteritidis / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D012486:Salmonella typhimurium / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; C025580:endodeoxyribonuclease XBAI; D015252:Deoxyribonucleases, Type II Site-Specific; C412613:CTX-M-9 protein, E coli; C456080:beta-lactamase CTX-M-14; D001618:beta-Lactamases; C034413:beta-lactamase TEM-1; D002439:Cefotaxime