A total of 259 clinical isolates of nonrepetitive non-typhi
salmonellae (NTS) were examined for
antibiotic resistance patterns and plasmid content. The antibiotics used
were
amoxicillin-clavulanic acid (AMC), ampicillin (AM), aztreonam
(ATM), carbenicillin (CB), cefixime
(CFM), cefotaxime (CTX), cefoxitin (FOX), ceftazidime (CAZ), ceftriaxone
(CRO),
chloramphenicol (C), ciprofloxacin (CIP), gentamicin (GM), imipenem (IPM),
ofloxacin (OFX),
tetracycline (TE), trimethoprim-sulfomethoxazole (SXT). Multi-drug resistant
(MDR) strains
comprised 19·3% of the total isolates (50/259) and almost all
were
S. typhimurium (49/50).
Fifteen different patterns of resistance was observed, AM/CB/C/AMC/TE
and
AM/CB/C/AMC/SXT/GM/CTX/CRO/CAZ/CFM/ATM
being the most frequent patterns.
Twenty-eight out of 50 multiresistant isolates were found to contain at
least one plasmid (mean
five) and the size of the plasmids ranged between 1·7 and 158 kb.
Plasmid profiles of
multi-resistant NTS strains were heterogenous as 21 different
profiles were detected in a total of 28
plasmid-bearing isolates. No direct correlation was established between
antibiotic resistance
patterns and plasmid profiles.