Antibiogram of Salmonella isolates from clinical specimens in Umuahia, Abia State, Nigeria

A study was carried out to determine the antibiogram of Salmonella isolates from clinical specimens in Umuahia, Abia state.  One hundred and thirty clinical specimens of blood and stool were asceptically collected, cultured, characterized and identified using standard microbiological methods. Molecular characterization using I6S rRNA was done to identify and characterize Salmonella isolate. Kirby–Bauer disc diffusion method using the protocol of the clinical and laboratory standard institute was carried out to determine the susceptibility profile of the isolates to ten different antimicrobials. Isolates that were resistant to at least three or four antibiotics were further subjected to plasmid profiling and curing of the resistant Salmonella isolate. Plasmid curing with sodium dodecyl sulphate (SDS), post-curing susceptibility testing was performed using agarose gel electrophoresis. Eighty-five isolates of Salmonella were recovered from two different clinical sources. Susceptibility profile of the uncured isolates to ten different antimicrobials revealed that the highest resistance percentage was against Ampicillin (73%), Vancomycin (66%), Nitrofurantoin (61%), Levofloxacin (54%), Gentamicin (51%), with moderate resistance to Ciprofloxacin (49%), Imipenem (41%) and lowest resistance rate to Ceftazidime (33%), Ofloxacin (34%) and Cefuroxime (39%). Then after plamid curing of the Salmonella isolates, the highest resistance percentage was against Ampicillin (72%), Vancomycin (62%), Nitrofurantoin (59%), Levofloxacin (51%), Gentamicin (51%), with moderate resistance to Ciprofloxacin (42%), Imipenem (41%) and lowest resistance rate to Ceftazidime (32%), Ofloxacin (32%), and Cefuroxime (38%). After plasmid curing, no significant difference (p>0.05) in the level of resistance was observed. The findings demonstrate widespread multidrug resistance of Salmonella in clinical samples. This definitely will create public health challenges and requires the need to innovate better antimicrobial treatment in our clinical and health settings.