Serum, bactericidal activity

Vogt. K., Rauhut, A.. Trautmann, M., and Hahn, H., Comparison of fosfomycin and teicoplanin in serum bactericidal activity against Staphylococci, Arzneim. Forsch., 45, 894, 1995. 

F2. Fierer, J., and Finley, F., Deficient serum bactericidal activity against Escherichia coli in patients with cir osis of the liver. J, Clin. Invest. 63, 912-921 (1979). 

Deeter, R.G. Weinstein, M.P. Swanson, K.A. Gross, J.S. Bailey, L.C. Crossover assessment of serum bactericidal activity and pharmacokinetics of five broad-spectrum cephalosporins in the elderly. An-timicrob.Agents Chemothen, 1990, 34, 1007—1013... 

Paradis, D. Vall4e, F. Allard, S. Bisson, C. Daviau, N. Drapeau, C. Auger, F. LeBel, M. Comparative study of pharmacokinetics and serum bactericidal activities of cefpirome, ceftazidime, ceftriaxone, imipenem, and ciprofloxacin. Aretimicro6.Agerafs Chemother., 1992, 36, 2085-2092... 

One study found that the pharmacokinetics of intravenous ciprofloxacin 200 mg were not affected by intravenous clindamycin 600 mg and there is evidence that combined use may possibly enhance the antibacterial activity, particularly against S. aureus and S. pneumoniae. However, another study found that the serum bactericidal activity of ciprofloxacin against S. aureus was completely antagonised by clindamycin, if the strains were susceptible to the latter. ... 

Weinstein MP, Deeter RG, Swanson Gross JS. Crossover assessment of serum bactericidal activity and pharmacokinetics of ciprofloxacin alone and in combination in healthy elderly volunteers. Antinacrob Agents Chemo r (1991) 35,2352—8. 

Boeckh M, Grineisen S, Shokry F, Koej P, Brnier K, Krasemann C, Lode H Pharmacokinetics and serum bactericidal activity (SBA) of ciprofloxacin (CEP) and ofloxacin (OFL) alone and in combination with metronidazole (METRO) or chnd ycin (CLINDA). Intersci C( tfAnturncrob Agents Chem( ter( 9 28,246. 

Lamp KC, Rybak MJ, Bailey EM, Kaatt GW. In vitro pharmacodynamic effects of conccn-tration, pH, and growth phase on serum bactericidal activities of daptomycin and vancomycin. Antimicrob Agent Chemother 1992 36 2709-2714. 

In vivo studies showed that in vitro proliferation of lymphocytes isolated from marijuana smokers is suppressed, especially with heavy marijuana smoking, and that the relative proportion of lymphocyte subpopulations was also altered. Concentrations of serum IgG are decreased and IgE concentrations are increased in marijuana smokers. Furthermore, phagocytic and bactericidal activity of alveolar macrophages from heavy marijuana smokers are decreased. These effects translate into reduced host resistance following administration of cannabinoids, including THC, in both humans and animals (Table 30.2). Increased susceptibility has been demonstrated to opportunistic microbes including HIV, Herpes simplex virus, Friend leukemia virus Listeria, Treponema pallidum, and Legionella. 

For drugs whose killing action is time-dependent, bactericidal activity continues as long as serum concentrations are greater than the MBC. Drug concentrations of time-dependent killing agents that lack a postantibiotic effect should be maintained above the MIC for the entire interval between doses. 

Cell wall agents, such as glycopeptides, have concentration-independent bactericidal activity, and the time over which the antibiotic serum concentration persists over the minimal inhibitory concentration of the pathogen is a main pharmacodynamic determination of the outcome. In a two-way, randomized, open, two-period, crossover study in 10 healthy adults, teicoplanin given in two 200 mg doses intramuscularly produced steady-state trough concentrations even higher than those after once-daily intravenous administration of 400 mg (3). Conversion from intravenous to intramuscular administration may therefore allow better compliance with preserved efficacy. Intramuscular teicoplanin was well tolerated. Adverse effects reported were mild local pain for 2-3 hours, headache, and backache. 

Hcpatocytes produce an array of acute phase praieins liable 7-4) that are released into the serum during inflammation or infection. These proteins do not act directly on baclc-ri.t. but they augment the bactericidal activity of other antimicrobial factors. 

Nifurprazine has a bactericidal action against micro-organisms in the logarithmic growth phase as well as in the stationary phase > . A 50 per cent content of human serum in the culture medium does not interfere with the bactericidal activity of the compound. Further clinical investigations showed that the compound is very effective against wound infections and a preparation for topical application was marketed in 1966. 

Dabemat, H., Delmas, C., Seguy, M., Fourtillan, J. B., Girault, J., and Lareng, M. B. (1991). The activity of clarithromycin and its 14-hydroxy metabolite against Haemophilus influenzae, determined by in vitro and serum bactericidal tests. J. Antimicrob. Chemother. 27, 19-30. 

Wolska, K., Bukowski, K., Anusz, Z., and Jakubczak, A. (1999). Bactericidal activity of human, swine and cattle serum against Pseudomonas aeruginosa strains. Med. Dosw. Mikrobiol. 51, 339-345. 

Kalman, D. Barriere, S.L. Johnson, B.L., Jr. Pharmacokinetic disposition and bactericidal activities of cefepime, ceftazidime, and cefoperazone in serum and blister fluid. Antimicrob.Agents Chemother., 1992, 36, 453-457... 

MECHANISM OF ACTION The aminoglycoside antibiotics are rapidly bactericidal. Bacterial killing is concentration-dependent, but residual bactericidal activity persists even after the serum concentration has fallen below the minimum inhibitory concentration. These properties account for the efficacy of once-daily dosing regimens. 

Vancomycin exhibits non-concentration-dependent bactericidal activity therefore, percent time > MIC or AUCiMIC should correlate with outcomes. As a result, investigators have attempted to optimize therapy by dosing vancomycin to maintain serum concentrations above the MIC of specific pathogens. As a means to optimize exposure, some chnicians continue to moiutor trough concentrations and attempt to maintain this concentration greater than the MIC of the pathogen. 

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