Activities of aztreonam and new cephalosporins against infrequently isolated gram-negative bacilli

Two veterinary pathogens, BordeteUa bronchiseptica and Bordetella avium, were tested for their antimicrobial susceptibilities. Of the 20 antimicrobial agents tested, both species were consistently resistant to penicillin and cefuroxime but susceptible to mezlocillin, piperacillin, gentamicin, amikacin, and cefoperazone.Bordetella bronchiseptica and Bordetella avium are important respiratory pathogens of swine and poultry, respectively. B. bronchiseptica is associated with atrophic rhinitis, a slow erosion of nasal turbinates in the snout. In a 1984 U.S. survey, 69% of midwestern hogs had some degree of atrophic rhinitis (11). B. bronchiseptica has also been isolated from rodents, felines, canines, and humans (2,3,6,7,9).B. avium (formerly Alcaligenes faecalis) is the causative agent of turkey coryza. Infected young turkeys experience oculonasal discharge, tracheal collapse, and decreased weight gains; but mortality is usually low (10). No comprehensive epidemiological studies on the incidence of B. avium infection are available.To date, in vitro antimicrobial susceptibility studies with these two organisms have been conducted with either small numbers of isolates (4) or against panels with limited numbers of antimicrobial agents (1,12 tested against all study isolates at the indicated ranges of concentrations: penicillin, 0.015 to 2.0 ,ug/ml; ampicillin, 0.25 to 16 ,ug/ml; ampicillin-sulbactam, 0.03/0.015 to 16/8 ,ug/ml; ticarcillin, 4 to 64 ,ug/ml; mezlocillin, 2 to 4 ,ug/ml; piperacillin, 1 to 64 ,ug/ml; gentamicin, 1 to 8 ,ug/ml; tobramycin, 1 to 8 ,uglml; amikacin, 2 to 32 ,ug/ml; cephalothin, 1 to 16 ,ug/ml; cefuroxime, 0.5 to 32 ,ug/ml; cefoperazone, 2 to 32 ,ug/ml; ceftazidime, 0.5 to 32 ,ug/ml; cefotaxime, 0.5 to 32 ,ug/ml; ceftriaxone, 0.5 to 32 pug/ml; chloramphenicol, 0.25 to 16 ,ug/ml; erythromycin, 0.12 to 8 ,uglml; rifampin, 0.015 to 4 ,ug/ml; trimethoprim-sulfamethoxazole, 0.5/9.5 to 32/608 ,ug/ mnl; and tetracycline, 0.25 to 16 ,ug/ml.The inoculum was a suspension of the organism in

supporting

confidence: 80%

mentioning

confidence: 99%

Antimicrobial susceptibility of Bordetella avium and Bordetella bronchiseptica isolates

Mortensen

Brumbach

Shryock

1989

“…Von Gravenitz (14) reviewed the clinical significance of flavobacteria. Strains of Flavobacterium odoratum isolated from clinical specimens have been shown to be resistant to penicillins, cephalosporins, imipenem, and aztreonam (12).…”

mentioning

confidence: 99%

Biochemical properties of beta-lactamase produced by Flavobacterium odoratum

Sato¹,

Fujii²,

Okamoto³

et al. 1985

A constitutively produced beta-lactamase was purified from Flavobacterium odoratum GN14053. The purified enzyme gave a single protein band on polyacrylamide gel electrophoresis. The isoelectric point was 5.8, and the molecular weight was estimated to be about 26,000. The enzyme activity was inhibited by EDTA, iodine, p-chloromercuribenzoate, HgCl2, and CuSO4 but not by clavulanic acid, sulbactam, imipenem, and cephamycin derivatives. The enzyme showed a broad substrate profile, hydrolyzing oxyiminocephalosporins, cephamycins, imipenem, and some penicillins.

“…Likewise, carumonam had very limited activity against a much larger spectrum of nonfermenters than suggested by earlier publications (3,4,11,13). Provided that sequential clinical isolates emanating from routine diagnostic testing in a hospital are as resistant to carumonam (MIC5.)…”

mentioning

confidence: 92%

In vitro activity of carumonam (Ro 17-2301; AMA-1080) versus enteropathogenic and nonfermentative gram-negative rods and Legionella pneumophila

Hohl

Graevenitz

Zollinger-Iten

1988

The in vitro activity of carumonam (Ro 17-2301; AMA-1080) was tested against 355 single-patient isolates, by and large enteropathogenic or nonfermentative rods. The new monobactam was inhibitory and bactericidal against the majority of diarrhea-causing members of the family Enterobacteriaceae at concentrations of less than and equal to 8 ,ug/ml. Although known to be active against Pseudomonas aeruginosa, it generally did not exhibit clinically useful activity against other nonfermenters or against Legionella pneumophila, thus confirming its narrow spectrum of activity.Carumonam (Ro 17-2301; AMA-1080) is a parenterally administered monocyclic beta-lactam (monobactam) currently under clinical development. This new agent has been shown to be active in vitro against many, predominantly gram-negative, aerobic rods, primarily members of the families Enterobacteriaceae and Neisseriaceae, Haemophilus spp., and Pseudomonas aeruginosa (1, 5, 7). Because the activity of carumonam has not been unequivocally defined with regard to its use for enteric and for nosocomial infections, the purpose of the present study was to determine its in vitro activity against the most ubiquitous causative agents of acute bacterial diarrhea, against the main nonfermentative gram-negative rods (except P. aeruginosa), and against Legionella pneumophila.A total of 355 clinical isolates from the culture collection of the Department of Medical Microbiology at the University of Zurich were selected for the study. The MIC of carumonam was determined by the microbroth dilution technique following widely accepted recommendations (8) in wells with 0.1-ml final volume by using cation-unsupplemented Mueller-Hinton broth (Difco Laboratories). The MIC was read with the unaided eye and taken as the lowest concentration of antibacterial agent that suppressed visible bacterial growth. Faintly turbid wells were disregarded. Halophilic Vibrio spp. were tested in Mueller-Hinton broth supplemented with 6.5% NaCl. Susceptibility testing of Campylobacter jejuni was carried out by agar dilution under microaerophilic conditions by using Mueller-Hinton agar (final amount, 2.5% agar) enriched with 7% horse blood incubated in an anaerobic jar without catalyst at 35°C for 48 h (12).Determination of Legionella pneumophila susceptibility (MIC only) was carried out on enriched charcoal-yeast extract agar in room air with added 10% CO2 (2) and 0.5 (1) jig/ml. Data for other organisms were as follows: Yersinia spp., 1 (8) ,ug/ml; Vibrio spp., 16 (16) jig/ml; and Salmonella spp., 1 (>128) j±g/ml. For Campylobacterjejuni, which was still more resistant to the compound, the M'C50 (MIC90) was 8 (128) jig/ml.Results with 191 nonfermentative rods (27 species) are not tabulated, since these bacteria were quite resistatit to caru-