Pharm Pract Manag Q. 1996 Jul;16(2):9-12.
Selecting antibiotics based on pharmacokinetic and pharmacodynamic principles.

Klutman NE.

School of Pharmacy, University of Kansas, Lawrence, KS 66045, USA.

Key pharmacokinetic and pharmacodynamic parameters influencing antimicrobial selection include the area under the curve (AUC) and minimum inhibitory concentration (MIC). These concepts can be integrated to describe the unique triangular relationship between the antibiotic, infecting organism, and patient. Antibiotic pharmacodynamics have been described as the ratio of AUC/MIC, maximum concentration to MIC, and time above MIC. These relationships can help define whether an antibiotic class kills by concentration-dependent or concentration-independent mechanisms. For example, aminoglycosides and fluoroquinolones have concentration-dependent killing while beta-lactams are concentration-dependent. This killing is also reflected in the post-antibiotic effect (PAE) that describes the prolonged activity even when the antibiotic levels are undetectable. These principles allow antibiotic classes to be selected and dosed via new strategies such as once daily aminoglycosides and continuous infusion beta-lactams.


Source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10161616&dopt=Abstract antibiotic, antibiotics



Scand J Infect Dis. 1975;7(4):259-64.
Evaluation of the antibiotic effect of treatment of maxillary sinusitis.

Carenfelt C, Eneroth CM, Lundberg C, Wretlind B.

As the effect of antibiotic treatment of maxillary sinusitis has been questioned, the elimination of bacteria from sinus secretions was studied during antibiotic treatment. Penicillin V, azidocillin, tetracycline or doxycycline was administered to 54 patients with maxillary sinusitis. Samples of sinus secretion were aspirated both before treatment and 2-3 days after the onset of treatment. When the antibiotic concentration was below the upper limit of MIC for sensitivity group 1, bacterial growth was present in practically all samples. When the antibiotic concentration equalled or was above this limit, there was no bacterial growth in about half of the samples. A prerequisite for antibiotic effect--elimination of bacteria--is that the antibiotic concentration is well above the MIC of the bacteria at the site of infection. The choice between bactericidal or bacteriostatic antibiotics appeared unimportant. Bacterial survival in the maxillary sinus despite a high antibiotic concentration in the sinus illustrates that MIC values determined in the laboratory do not always mirror the sensitivity of bacteria to antibiotics in vivo.


Source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1848&dopt=Abstract antibiotic, antibiotics



Pol Arch Med Wewn. 2002 Oct;108(4):965-9.
[Serological tests for detection of fungal infection connected with prolonged antibiotic treatment after valve replacement]

[Article in Polish]

Orlowska-Baranowska E, Dabkowska M, Rawczynska-Englert I.

In recent years substantial progress has been seen in the development of approaches and methods for serological diagnosis of the mycosis. The aim of our study was to assess the clinical usefulness of serological tests for fungal infection in pts who underwent prolonged antibiotic therapy after valve replacement. MATERIAL AND METHODS: The group consisted of 27 pts after valve replacement with prolonged antibiotic therapy (6-12 weeks) due to infective endocarditis (22 pts) or sternal infection (5 pts). The samples of blood were taken 10 days after antibiotics were started and next every 10 days. Serological techniques for the diagnosis of Candidiasis consisted of antibody detection to: the cell wall polysaccharide antigen (test A), cytoplasmic protein antigen (test B) and the germ tube antigens (test C). RESULTS: Patients were divided in 3 groups due to the kinetics of the antibody responses to the Candida antigen: 1. pts with normal level of antibody during antibiotic treatment--they didn't required antifungal therapy, 2. pts with increasing level of antibody needed antifungal treatment, 3. pts with increasing kinetics of antibody responses during antibiotic and antifungal treatment needed the change of antifungal therapy, 4. Control group (pts before cardiac surgery without any sign of fungal infection). Antibody to the cytoplasmic antigen was detected infrequently. The presence of antibody to the cytoplasmic antigen was correlated with the patient clinical outcome and prognosis and necessity for change of antifungal therapy. One pt died after valve replacement due to valve dysfunction because of fungal endocarditis. CONCLUSIONS: Serological tests for Candidiasis can be a useful marker of fungal infection, prognosis and treatment in pts required prolonged antibiotic therapy after valve replacement.


Source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12642941&dopt=Abstract antibiotic, antibiotics



Pharmacoepidemiol Drug Saf. 2003 Mar;12(2):113-20.
Prescriptions of systemic antibiotics for children in Germany aged between 0 and 6 years.

Schindler C, Krappweis J, Morgenstern I, Kirch W.

Institute of Clinical Pharmacology, Medical Faculty, Technical University, Fiedlerstrasse 27, D-01307 Dresden, Germany. christoph.schindleailbox.tu-dresden.de

Limited information is available about systemic antibiotic use among children in Germany. We therefore assessed prescription patterns by office-based physicians to analyse antibiotic consumption in early childhood. A total of 331 children < 6 years were eligible for inclusion. The number of antibiotic prescriptions, consumed daily doses, number of treatment courses, types of antibiotics and diagnoses for prescribing were determined. The prevalence of systemic antibiotic treatment was 42.9%. Antibiotic consumption was highest between 2 and 3 years of age (55.8%). The percentage of children receiving one, two or three courses of antibiotic treatment was 49.3, 28.2 and 16.2%, respectively. Acute otitis media (32.2%), upper respiratory tract infections (18.9%), tonsillitis (15.9%) and acute bronchitis (15.4%) were principal indications for treatment. Macrolides were most frequently prescribed (48.1%), followed by penicillin V (21.3%), broad-spectrum penicillins (14.3%), sulfonamides (10.5%) and cephalosporins (5.8%). Antibiotics not recommended for particular indication were selected in 5-43% of cases. The considerable prescription of systemic antibiotics to children in many European countries is also the case in Germany. A noteworthy trend emerged for suboptimal prescribing with second-line antibiotics. As such treatment may be associated with the development of bacterial resistance, improved guidelines for antibiotic treatment should be drawn up and enforced.


Source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12642974&dopt=Abstract antibiotic, antibiotics



Pharmazie. 1976;31(2):105-9.
The in vitro adsorption of some antibiotics on antacids.

Khalil SA, Daabis NA, Naggar VF, Motawi MM.

The adsorption of oxytetracycline hydrochloride, tetracycline hydrochloride, doxycycline hyclate, triacetyloleandomycin, chloramphenicol, ampicillin, and cloxacillin sodium was studied on various antacids namely, magnesium trisilicate, magnesium oxide, calcium carbonate, bismuth oxycarbonate, aluminium hydroxide, and kaolin. The adsorption of the various antibiotics by milk was also tested as milk is frequently used as an antacid. Charcoal was included in the present study as a model adsorbent having a large hydrophobic surface. The adsorption of the various antibiotics on the different antacids and other adsorbents in most cases obeyed the Freundlich adsorption isotherm. Magnesium trisilicate and magnesium oxide showed the highest adsorptive capacity, relative to other antacids used, for most antibiotics. Calcium carbonate and aluminium hydroxide and intermediate power while kaolin and bismuth oxycarbonate had the least adsorptive power. Charcoal exhibited a marked adsorption for all antibiotics tested. Tetracyclines were found to be more highly adsorbed than other antibiotics studied. Triacetyloleandomycin and chloramphenicol had intermediate values. Ampicillin was only adsorbed to a slight extent while cloxacillin was not adsorbed on the antacids used. The extent of adsorption was correlated to the structure of both the adsorbent and adsorbate, the pH of the adsorbent suspension, and to the polarity of the antibiotic in such pH. The reversibility of the adsorption process was studied in different media and at pH values similar to those of the gastrointestinal tract. The extent of elution was found to be inversely proportional to the adsorptive capacity of the different adsorbents. In general, 0.0143 n NaHCO3 solution was found to possess higher eluting properties than 0.01 n HCl. An exception to this pattern was observed with tetracyclines adsorbed on aluminium hydroxide where the elution with acid resulted in a higher degree of desorption. Careful in vitro and in vivo testing of drug availability is advisable prior to the concomitant administration of antibiotics with antacids or other adsorbents.


Source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8784&dopt=Abstract antibiotic, antibiotics



Int J Antimicrob Agents. 2000 Nov;16(3):211-7.
Natural antibiotic susceptibility of Salmonella enterica strains.

Stock I, Wiedemann B.

Institut fur Medizinische Mikrobiologie und Immunologie, Pharmazeutische Mikrobiologie, Meckenheimer Allee 168, D-53115, Bonn, Germany. ingostocotmail.com

The susceptibility of 100 Salmonella enterica strains belonging to S. enterica subsp. enterica (n=90) and S. enterica subsp. arizonae (n=10) was examined to 71 antibiotics. Within S. enterica subsp. enterica, strains of different serovars (typhimurium (n=17), enteritidis (n=17), dublin (n=10), typhi (n=16), paratyphi A (n=6), others (n=24)) were studied. MICs were determined using a microdilution procedure and apart from fosfomycin there were no significant differences in susceptibility between the subspecies and serovars of S. enterica. All salmonellae were sensitive or intermediately resistant to tetracyclines, aminoglycosides, most beta-lactam antibiotics, quinolones, co-trimoxazole group antibiotics, chloramphenicol, nitrofurantoin and azithromycin. S. enterica strains were intrinsically resistant to benzylpenicillin, oxacillin, most macrolides, rifampicin, lincosamides, streptogramins, glycopeptides and fusidic acid. Apart from some slight differences in antibiotic susceptibility between strains of S. enterica subsp. enterica and S. enterica subsp. arizonae, only the susceptibility to fosfomycin varied among the taxa studied. Whereas 'enteric' salmonellae including S. enterica subsp. arizonae were sensitive to fosfomycin, 'typhoid' salmonellae were intrinsically resistant. A database of the antibiotic susceptibility of S. enterica was set up. It may be of use to validate antibiotic susceptibility test results of these bacteria.


Source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11091038&dopt=Abstract antibiotic, antibiotics



Bioorg Med Chem. 2000 Nov;8(11):2609-16.
Binding of vancomycin group antibiotics to D-alanine and D-lactate presenting self-assembled monolayers.

Cooper MA, Fiorini MT, Abell C, Williams DH.

Department of Chemistry, University Chemical Laboratory, Cambridge, UK.

Peptides terminating in -Lys-D-Ala-D-Ala, -Lys-D-Ala-L-Ala and -Lys-D-Ala-D-Lactate were covalently coupled via an N-terminal aminohexanoic acid linker to a self-assembled monolayer of HS(CH2)15CO2H on a thin gold film. Binding of the glycopeptide antibiotics vancomycin and chloroeremomycin to these surfaces was then measured using a surface plasmon resonance biosensor. Both antibiotics bound with micromolar affinity to the D-Ala-terminating surface and with millimolar affinity to the D-Lactate-terminating surface. Increasing density of these covalently attached peptides on the surface had no effect on the resultant affinities of either antibiotic for the surface. In contrast, when the lipid-anchored peptide N-alpha-docosanoyl-epsilon-acetyl-Lys-D-Ala-D-Ala was inserted into a supported lipid monolayer, the affinity of the strongly dimerizing antibiotic chloroeremomycin for the surface showed a dependence on ligand density. This was not the case with the weakly dimerizing antibiotic vancomycin. The lipid monolayer surface, which is a more realistic model of the surface of a bacterium, was thus better suited for the study of the cooperative binding interactions that occur between dimeric glycopeptide antibiotics and surface-bound ligands.


Source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11092546&dopt=Abstract antibiotic, antibiotics



Ann Clin Microbiol Antimicrob. 2003 Feb 27;2(1):3.
Central venous catheter related infections: Risk factors and the effect of glycopeptide antibiotics.

Oncu S, Ozsut H, Yildirim A, Ay P, Cakar N, Eraksoy H, Calangu S.

Department of Infectious Diseases and Clinical Microbiology, Adnan Menderes University Faculty of Medicine, Aydin, Turkey. serkanoncotmail.com

BACKROUND: We undertook a prospective study of all new central venous catheters inserted into patients in the intensive care units, in order to identify the risk factors and to determine the effect of glycopeptide antibiotics on catheter - related infections. METHODS: During the study period 300 patients with central venous catheters were prospectively studied. The catheters used were nontunneled, noncuffed, triple lumen and made of polyurethane material. Catheters were cultured by semiquantitative method and blood cultures done when indicated. Data were obtained on patient age, gender, unit, primary diagnosis on admission, catheter insertion site, duration of catheterization, whether it was the first or a subsequent catheter and glycopeptide antibiotic usage. RESULTS: Ninety-one (30.3%) of the catheters were colonized and infection was found with 50 (16.7%) catheters. Infection was diagnosed with higher rate in catheters inserted via jugular vein in comparison with subclavian vein (95% CI: 1.32-4.81, p = 0.005). The incidence of infection was higher in catheters which were kept in place for more than seven days (95% CI 1.05-3.87, p = 0.03). The incidence of infection was lower in patients who were using glycopeptide antibiotic during catheterization (95% CI: 1.49-5.51, p = 0.005). The rate of infection with Gram positive cocci was significantly lower in glycopeptide antibiotic using patients (p = 0.01). The most commonly isolated organism was Staphylococcus aureus (n = 52, 37.1%). CONCLUSION: Duration of catheterization and catheter insertion site were independent risk factors for catheter related infection. Use of glycopeptide antibiotic during catheterization seems to have protective effect against catheter related infection.


Source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12643811&dopt=Abstract antibiotic, antibiotics [PubMed - as supplied by publisher]