Accurate measurement of serum concentrations of antimicrobial agents is important when the margin between therapeutic and toxic levels is narrow. Finally because various body tissues bind antimicrobial agents with different capacities 39 and tissue fluidantibiotic concentration is a combination of bound and unbound drug 40 it is necessary to know the protein binding of an antibiotic to both the tissue or body fluid and plasma or serum in order to interpret correctly the significance of the tissue concentration. Measurement of bactericidal activity in body fluids as a clinical research procedure. Antimicrobial levels and renal function for most antimicrobial agents renal excretion is the major pathway for elimination from the. Pharmatokinetic properties of antimicrobial drugs determine the dosage the dosing frequency and. Concentration of antibacterial agents in interstitial tissue fluid.
With the availability of rapid accurate assays the measurement of antibiotic material in serum and other body fluids is feasible desirable and widely practiced for these purposes. A simple micro agar diffusion method for the determination of antibiotic concentrations in blood and other body fluids. Indian journal of medical. Correlation of in vitro resistance ofn. The values given for serum and urine were obtained from normal adults in controlled phar macologic studies table 1. In contrast dilution methods allow determination of the minimal inhibitory concentration of an agent which can be correlated with blood urine and other body fluid levels of the antimicrobial agent.
Antimicrobial agents and chemotherapy. Gonorrheae strains with clinical response to penicillin and its blood levels. Pmc free article georgopoulos a. Pharmacokinetic studies of antimicrobial therapy relate the administration of the drug to the concentration time profile within body fluids and include its absorption distribution metabolism and excretion properties. In human subjects concentrations of drug in body fluids have been reported 4 7 9 11 12. Drutz from the division of infectious diseases department of medicine university of texas health science center san antonio texas interpretation of in vitro susceptibility data for antifungal drugs is hindered by the ab.
For the other body fluids listed the subjects were generally hospitalized patients table 2. Chisholm gd waterworth pm calnan js garrod lp. In vitro antifungal susceptibility testing and measurement of levels of antifungal agents in body fluids david j. Laboratory tests used to guide antimicrobial therapy. However detailed studies of concentrations in tissue and pharmacokinetics are lacking. The fact that the native structure of fluconazole contains two fluorine atoms makes it an ideal candidate for radiolabeling with 18f.
Laboratory tests that can be helpful in guiding antimicrobial therapy include antimicrobial susceptibility testing determination of bacterial beta lactamase production assay of serum inhibitory and bactericidal activity and assay of specific antibiotic levels in serum. The measurement of antibiotic concentrations in various fluids has been a prominent aspect of the evaluation of new antibiotics and the quality control of their manufacture.