title: Antibiotic resistance mechanisms in Salmonella species causing bacteraemia in Malawi and Kenya.
abstract: In two studies on the causative agents of bacteraemia in Malawi and Kenya, 33 Salmonella strains were isolated. Fourteen strains of Salmonella typhimurium and Salmonella enteritidis were found to exhibit resistance to amoxicillin, amoxicillin/clavulanic acid and cotrimoxazole as well as decreased susceptibility to a range of aminoglycosides. The resistant strains were studied to establish their resistance mechanisms. Beta-lactamase co-focusing with TEM-1 was present in 12 strains. In two strains, both S. typhimurium from Kenya, an OXA-1 beta-lactamase was detected. The aminoglycoside-modifying enzyme ANT(2") was found in 10 strains. The presence of the encoding genes was confirmed by PCR. For comparison, susceptibility records of 73 Salmonella strains isolated during the past 14 years in our hospital were studied retrospectively. Only one of these strains was resistant to amoxicillin. This resistance was acquired during therapy.
authors.affiliation: Department of Medical Microbiology, Leiden University Hospital, The Netherlands.
authors.forename: T M
authors.initials: TM
authors.lastname: Leegaard
authors.forename: M H
authors.initials: MH
authors.lastname: van Gestel
authors.forename: P L
authors.initials: PL
authors.lastname: Petit
authors.forename: J A
authors.initials: JA
authors.lastname: van de Klundert
mesh_terms: D000668:Ampicillin Resistance; D016470:Bacteremia / Q000453:epidemiology* / Q000382:microbiology*; D001483:Base Sequence; D004352:Drug Resistance, Microbial; D007630:Kenya / Q000453:epidemiology; D008295:Malawi / Q000453:epidemiology; D016106:Methicillin Resistance; D008969:Molecular Sequence Data; D012477:Salmonella enteritidis / Q000187:drug effects*; D012486:Salmonella typhimurium / Q000187:drug effects*; D014296:Trimethoprim Resistance; D018440:beta-Lactam Resistance