Survival patterns of some common pathogens in human plasma following exposure to a sub-inhibitory concentration of ceftriaxone sodium

Abstract

The survival of Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa in human plasma was investigated following their exposure to a sub-inhibitory concentration of ceftriaxone sodium. The aim was to determine the possible effect of human immune agents present in the plasma on microorganisms that may have been previously exposed to sub-inhibitory concentrations of antibiotics. Microbial survival was assessed by viable cell counts conducted at hourly intervals over a period of 5 hours. Subsequently, surviving organisms were used to determine the minimal inhibitory concentration of the antibiotics. The results showed that the rate of replication of P. aeruginosa in plasma was significantly reduced after exposure to a subinhibitory concentration of ceftriaxone sodium. On the contrary, there was an increase in the minimum inhibitory concentration of the antibiotic after K. pneumoniae or E. coli were exposed to the sub-inhibitory antibiotic concentration. This implies that, while some organisms were weakened by sub-lethal doses of ceftriaxone sodium to the extent of susceptibility to human immune agents, others gained resistance to both the antibiotic and the immune system.

Effect of Sub-Inhibitory Concentrations of Flucloxacillin or Clindamycin and Plasma on Staphylococcus aureus Clinical Isolate

“…[6,7]Plasma cellsare not only capable of secreting high specialized antibodies, but assist in the transportation of certain agents, such as leukocytes, macrophages, drugs and alcohol, which make it an important inhibitory environment for invading pathogens. [9] Previous studies by Okoreet al [9] indicates that a patient's immune system may become very weak and not able to get rid of invading pathogens and in such circumstances, medication maybe required to fight the infection.It is common knowledge that a lot of people of developing countries especially in the third world countries practise self-medication while a lot more would not take their medication correctly. [9]This practice exposes the invading organisms to sub-inhibitory doses of the drugs.Sub inhibitory concentrations, is known to stimulate mutation and, consequently, bacterial adaptation to different stresses, including antibiotic pressure.…”

“…[10] and has become a course for concern worldwide. [9,11,12] The inappropriate use of antibiotics for different human activities and the uncontrolled abuse of these compounds for therapeutic purposes has had a major impact, leading to the selection and spread of resistant. [10,13]Thisphenomenonhas resulted in the selection of pre-existing resistant variants that ultimately become fixed in our communities.…”