Plasmid mediated resistance in multidrug resistant bacteria isolated from children with suspected septicaemia in Zaria, Nigeria

Abstract

Septicaemia is a common cause of morbidity and mortality among children in the developing world. The knowledge of the epidemiological and antimicrobial pattern of common pathogens that cause septicaemia is useful for prompt treatment of patients. Fifty-five (55) clinical isolates from children with suspected septicaemia were used for the study. The isolates include Coagulase negative Staphylococcus, Staphylococcus aureus, Salmonella spp., Klebsiella spp., Citrobacter spp., Proteus spp and Pseudomonas spp. The antibiotic susceptibility testing of isolated bacteria associated with septicaemia in children were carried out using standard microbiological protocol. The MAR index for the test bacterial isolates was determined and the bacterial isolates that displayed multiple antibiotic resistance were investigated for the presence of resistant factor such as plasmids. The sizes of the plasmid observed in the bacterial isolates were determined using agarose gel electrophoresis. Observations made from the agarose gel electrophoresis showed that majority of the multiple antibiotic resistant isolates haboured plasmids DNA of different sizes viz: 10.00 Kb, 8.71 Kb, 7.08 Kb, 1.02 Kb, 1.00 Kb, 0. 98 Kb and 0.87 Kb. The plasmid analysis of the results obtained in this study showed that the predominant plasmid molecular size was 977bp which occurred frequently among the Citrobacter spp and Staph aureus . These findings suggest an increased resistance to the antibiotics commonly used for the treatment of septicaemia, and the observed presence of plasmids in some of the test bacteria isolated shows that they could have been acquired from multiple antibiotic resistant bacteria in the community under investigation. Key words: Children, Multiple antibiotic resistance, Plasmids, Septicaemia