Biomaterial Database

The treatment of irradiated mice with polymicrobial infection caused by Bacteroides fragilis and Escherichia coli. 1994

I Brook, and G D Ledney

Experimental Hematology Department, Armed Forces Radiobiology Research Institute, Bethesda, MD 20814-5145.

The effects on the faecal flora and the efficacies of various antibiotic regimens administered as treatment for a mixed infection caused by Bacteroides fragilis and Escherichia coli in the irradiated host were investigated in a subcutaneous abscess model with C3H/HeN mice which had been exposed to 60Co. The regimens used included imipenem, ofloxacin, metronidazole and the combination of ofloxacin and metronidazole. The incidence of mortality associated with each regimen was as follows: 2 of 20 (10%) mice treated with ofloxacin; 16 of 20 (80%) given metronidazole (P < 0.05 compared with ofloxacin); 8 of 20 (40%) given imipenem (P < 0.05 compared with ofloxacin); 5 of 20 (25%) given the combination of ofloxacin and metronidazole (P = NS compared with ofloxacin); and 15 of 20 (75%) controls given a placebo (P < 0.05 compared with ofloxacin). Compared with the control group, the mean number of lactose-fermenting facultative anaerobes in the faeces of irradiated mice decreased significantly during treatment with either ofloxacin or ofloxacin combined with metronidazole; rose significantly from day 6 during treatment with metronidazole and was similar during treatment with imipenem. The numbers of strict anaerobes fell with all regimens (including the placebo) but, compared with the control group, were significantly higher in the ofloxacin and imipenem groups and significantly lower in the groups which received metronidazole (with or without ofloxacin). Imipenem and the combination of ofloxacin and metronidazole led to significant reductions in the numbers of cfu of both E. coli and B. fragilis in the abscesses compared with the placebo; ofloxacin alone caused a reduction in the number of cfu of E. coli only and metronidazole alone caused a reduction in the number of cfu of B. fragilis only. While the administration of metronidazole had a favourable effect on the B. fragilis component of the localized infection, there was a higher incidence of mortality with this agent, probably because it led to an increase in the number of Enterobacteriaceae in the faeces at the expense of a reduction in the number of strict anaerobes. Antimicrobial agents such as imipenem or the combination of a quinolone, such as ofloxacin, and metronidazole may be used successfully to treat localized infections in the irradiated host while avoiding potentially deleterious increases in the number of facultative anaerobes in the bowel.

UI	MeSH Term	Description	Entries
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D008795	Metronidazole	A nitroimidazole used to treat AMEBIASIS; VAGINITIS; TRICHOMONAS INFECTIONS; GIARDIASIS; ANAEROBIC BACTERIA; and TREPONEMAL INFECTIONS.	2-Methyl-5-nitroimidazole-1-ethanol,Bayer 5360,Clont,Danizol,Flagyl,Gineflavir,Metric,MetroGel,Metrodzhil,Metrogyl,Metronidazole Hydrochloride,Metronidazole Monohydrochloride,Metronidazole Phosphate,Metronidazole Phosphoester,Satric,Trichazol,Trichopol,Trivazol,Vagilen,2 Methyl 5 nitroimidazole 1 ethanol
D008826	Microbial Sensitivity Tests	Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).	Bacterial Sensitivity Tests,Drug Sensitivity Assay, Microbial,Minimum Inhibitory Concentration,Antibacterial Susceptibility Breakpoint Determination,Antibiogram,Antimicrobial Susceptibility Breakpoint Determination,Bacterial Sensitivity Test,Breakpoint Determination, Antibacterial Susceptibility,Breakpoint Determination, Antimicrobial Susceptibility,Fungal Drug Sensitivity Tests,Fungus Drug Sensitivity Tests,Sensitivity Test, Bacterial,Sensitivity Tests, Bacterial,Test, Bacterial Sensitivity,Tests, Bacterial Sensitivity,Viral Drug Sensitivity Tests,Virus Drug Sensitivity Tests,Antibiograms,Concentration, Minimum Inhibitory,Concentrations, Minimum Inhibitory,Inhibitory Concentration, Minimum,Inhibitory Concentrations, Minimum,Microbial Sensitivity Test,Minimum Inhibitory Concentrations,Sensitivity Test, Microbial,Sensitivity Tests, Microbial,Test, Microbial Sensitivity,Tests, Microbial Sensitivity
D004352	Drug Resistance, Microbial	The ability of microorganisms, especially bacteria, to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).	Antibiotic Resistance,Antibiotic Resistance, Microbial,Antimicrobial Resistance, Drug,Antimicrobial Drug Resistance,Antimicrobial Drug Resistances,Antimicrobial Resistances, Drug,Drug Antimicrobial Resistance,Drug Antimicrobial Resistances,Drug Resistances, Microbial,Resistance, Antibiotic,Resistance, Drug Antimicrobial,Resistances, Drug Antimicrobial
D004359	Drug Therapy, Combination	Therapy with two or more separate preparations given for a combined effect.	Combination Chemotherapy,Polychemotherapy,Chemotherapy, Combination,Combination Drug Therapy,Drug Polytherapy,Therapy, Combination Drug,Chemotherapies, Combination,Combination Chemotherapies,Combination Drug Therapies,Drug Polytherapies,Drug Therapies, Combination,Polychemotherapies,Polytherapies, Drug,Polytherapy, Drug,Therapies, Combination Drug
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D004927	Escherichia coli Infections	Infections with bacteria of the species ESCHERICHIA COLI.	E coli Infections,E. coli Infection,Infections, E coli,Infections, Escherichia coli,E coli Infection,E. coli Infections,Escherichia coli Infection,Infection, E coli,Infection, E. coli,Infection, Escherichia coli
D005243	Feces	Excrement from the INTESTINES, containing unabsorbed solids, waste products, secretions, and BACTERIA of the DIGESTIVE SYSTEM.
D005260	Female		Females
D000038	Abscess	Accumulation of purulent material in tissues, organs, or circumscribed spaces, usually associated with signs of infection.	Abscesses