Biomaterial Database

Susceptibility of multidrug-resistant strains of Mycobacterium tuberculosis to amoxycillin in combination with clavulanic acid and ethambutol. 1998

G Abate, and H Miörner

Department of Mycobacteriology, Statens Serum Institut, Copenhagen, Denmark. hmi@ssi.dk

Thirty clinical isolates of Mycobacterium tuberculosis, 20 of which were multidrug-resistant (MDR), were tested for susceptibility to different combinations of amoxycillin, clavulanic acid and subinhibitory concentrations of ethambutol. beta-Lactamase production was assessed semiquantitatively with the nitrocefin method and susceptibility testing was performed with the BACTEC method. All isolates were beta-lactamase positive and were resistant to 16 mg/L amoxycillin. The MIC of amoxycillin in combination with clavulanic acid was > or =2 mg/L for 27/30 (90%) isolates. Addition of subinhibitory concentrations of ethambutol significantly reduced the MIC of amoxycillin for all tested isolates. Twenty-nine (97%) isolates had an MIC of amoxycillin of < or =0.5 mg/L when subinhibitory concentrations of ethambutol were added; this is well below the concentrations achievable in serum and tissue.

UI	MeSH Term	Description	Entries
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
D009169	Mycobacterium tuberculosis	A species of gram-positive, aerobic bacteria that produces TUBERCULOSIS in humans, other primates, CATTLE; DOGS; and some other animals which have contact with humans. Growth tends to be in serpentine, cordlike masses in which the bacilli show a parallel orientation.	Mycobacterium tuberculosis H37Rv
D004357	Drug Synergism	The action of a drug in promoting or enhancing the effectiveness of another drug.	Drug Potentiation,Drug Augmentation,Augmentation, Drug,Augmentations, Drug,Drug Augmentations,Drug Potentiations,Drug Synergisms,Potentiation, Drug,Potentiations, Drug,Synergism, Drug,Synergisms, Drug
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
D004977	Ethambutol	An antitubercular agent that inhibits the transfer of mycolic acids into the cell wall of the tubercle bacillus. It may also inhibit the synthesis of spermidine in mycobacteria. The action is usually bactericidal, and the drug can penetrate human cell membranes to exert its lethal effect. (From Smith and Reynard, Textbook of Pharmacology, 1992, p863)	Dexambutol,EMB-Fatol,EMB-Hefa,Etambutol Llorente,Ethambutol Hydrochloride,Etibi,Miambutol,Myambutol,EMB Fatol,EMB Hefa,Hydrochloride, Ethambutol,Llorente, Etambutol
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000658	Amoxicillin	A broad-spectrum semisynthetic antibiotic similar to AMPICILLIN except that its resistance to gastric acid permits higher serum levels with oral administration.	Hydroxyampicillin,Actimoxi,Amoxicillin Anhydrous,Amoxicillin Monopotassium Salt,Amoxicillin Monosodium Salt,Amoxicillin Sodium,Amoxicillin Trihydrate,Amoxicillin, (R*)-Isomer,Amoxicilline,Amoxil,Amoxycillin,BRL-2333,Clamoxyl,Clamoxyl G.A.,Clamoxyl Parenteral,Penamox,Polymox,Trimox,Wymox,BRL 2333,BRL2333
D000995	Antitubercular Agents	Drugs used in the treatment of tuberculosis. They are divided into two main classes: "first-line" agents, those with the greatest efficacy and acceptable degrees of toxicity used successfully in the great majority of cases; and "second-line" drugs used in drug-resistant cases or those in which some other patient-related condition has compromised the effectiveness of primary therapy.	Anti-Tuberculosis Agent,Anti-Tuberculosis Agents,Anti-Tuberculosis Drug,Anti-Tuberculosis Drugs,Antitubercular Agent,Antitubercular Drug,Tuberculostatic Agent,Tuberculostatic Agents,Antitubercular Drugs,Agent, Anti-Tuberculosis,Agent, Antitubercular,Agent, Tuberculostatic,Anti Tuberculosis Agent,Anti Tuberculosis Agents,Anti Tuberculosis Drug,Anti Tuberculosis Drugs,Drug, Anti-Tuberculosis,Drug, Antitubercular
D001618	beta-Lactamases	Enzymes found in many bacteria which catalyze the hydrolysis of the amide bond in the beta-lactam ring. Well known antibiotics destroyed by these enzymes are penicillins and cephalosporins.	beta-Lactamase,beta Lactamase,beta Lactamases
D018088	Tuberculosis, Multidrug-Resistant	Tuberculosis resistant to chemotherapy with two or more ANTITUBERCULAR AGENTS, including at least ISONIAZID and RIFAMPICIN. The problem of resistance is particularly troublesome in tuberculous OPPORTUNISTIC INFECTIONS associated with HIV INFECTIONS. It requires the use of second line drugs which are more toxic than the first line regimens. TB with isolates that have developed further resistance to at least three of the six classes of second line drugs is defined as EXTENSIVELY DRUG-RESISTANT TUBERCULOSIS.	Tuberculosis, Drug-Resistant,Tuberculosis, MDR,Tuberculosis, Multi-Drug Resistant,Drug-Resistant Tuberculosis,MDR Tuberculosis,Multi-Drug Resistant Tuberculosis,Multidrug-Resistant Tuberculosis,Tuberculosis, Drug Resistant,Tuberculosis, Multi Drug Resistant,Tuberculosis, Multidrug Resistant