Objectives: To provide a summary of useful up-to-date knowledge regarding experimental and clinical bacteriology, pharmacokinetics and pharmacodynamics in order to optimise efficacy of antibiotic treatment of hospital patients with serious bacterial infections.
Data sources: Record of references from national and international journals in Medline.
Study selection: Extraction of the most relevant theoretical and practical data from studies published over the last 5 years.
Data synthesis: Changes in resistance to antibiotics, as well as the limited number of new antibacterial drugs available and the cost of therapeutic failure all militate in favour of a more elaborate approach to therapeutic strategies involving antibiotics, particularly regarding hospitalised patients. The efficacy of antibiotic therapy can be optimised through the utilization of bacteriological, pharmacokinetic and pharmacodynamic data, thereby increasing the likelihood of a successful outcome. While the antibiogram constitutes the fundamental analytical tool for evaluating the activity of antibiotics, the minimum inhibitory concentration (MIC) is of value in selecting appropriate drugs and dosages, particularly for bacterial strains having lower susceptibility. Screening for genes of resistance to antibiotics provides more accurate analysis of bacterial resistance. In recent years, the efficacy of antibiotics has been improved through the use of a number of pharmacodynamic parameters: inhibitory quotient (IQ), area under the serum concentration-time curve to MIC ratio (AUC/MIC) and the time the serum concentration is greater than the MIC (T > MIC). In standard practice, data readily available to the clinician comprise the MIC and serum antibiotic concentrations. There is some discussion concerning optimisation of antibiotic efficacy through the use of these parameters.
Conclusion: Close collaboration between clinicians and microbiologists results in improved quality of antibiotic therapy and better management of antibiotics.