7432-s and Gram-Positive-Bacterial-Infections

Topics: Administration, Oral; Adult; Ceftibuten; Cephalosporins; Child, Preschool; Enterobacteriaceae Infections; Gram-Positive Bacterial Infections; Humans; Infant; Microbial Sensitivity Tests; Respiratory Tract Infections; Urinary Tract Infections

Clinical and bacteriological efficacies of some antibacterial agents were estimated with their differential use in the management of various groups of patients with community-acquired pneumonia. Group 1 included young and middle-aged patients with mild pneumonia. Group 2 included young and middle-aged patients with moderate pneumonia. Group 3 included elderly patients with pneumonia and/or patients with concomitant diseases or certain factors complicating the main process. The patients of group 1 were treated with roxithromycin and spiramycin and showed a rapid clinical effect in 100 and 86 per cent of the cases and a rapid bacteriological effect in 84 and 75 per cent of the cases respectively. The patients of group 2 were treated with parenteral cefuroxime with positive clinical and bacteriological effects in 68 and 78 per cent of the cases respectively. The patients of group 3 were treated with ceftibuten and pefloxacin which provided a clinical effect in 91 and 70 per cent of the cases and a bacteriological effect in 72 and 100 per cent of the cases respectively. The results of the treatment with an account of the differences in the pathogen spectra made it possible to recommend as the 1st order agents for the empirical therapy of community-acquired pneumonia (1) macrolide antibiotics for young and middle-aged patients with mild pneumonia without concomitant diseases, (2) 2nd generation cephalosporins for patients with moderate pneumonia without severe concomitant diseases and (3) 3rd generation cephalosporins or fluoroquinolones for elderly patients with pneumonia and the patients with complicating factors.

Topics: Administration, Oral; Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Anti-Infective Agents; Ceftibuten; Cefuroxime; Cephalosporins; Community-Acquired Infections; Female; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Gram-Positive Bacterial Infections; Gram-Positive Cocci; Humans; Male; Middle Aged; Pefloxacin; Pneumonia, Bacterial; Roxithromycin; Spiramycin

In this investigation, the urine samples obtained in a single oral-dose pharmacokinetic study were examined for their bactericidal activity against a range of relevant urinary tract pathogens.. Six healthy volunteers received a single oral dose of ten oral antibiotics available in Croatia. Urine samples were taken every 2 h during the whole dosing interval of the particular antibiotic. The urinary bactericidal activity was tested by determination of urinary bactericidal titers.. All antibiotics showed a significant urinary bactericidal activity against non-extended spectrum beta-lactamase Escherichia coli and Proteus mirabilis. Fluoroquinolones displayed high and persisting levels of urinary bactericidal activity against all gram-negative bacteria and Staphylococcus saprophyticus.. Average urinary bactericidal activity can be predicted from in vitro susceptibility testing, but we expect that there will be patients with a low level of urinary bactericidal activity.

Topics: Acetamides; Administration, Oral; Adult; Amoxicillin; Amoxicillin-Potassium Clavulanate Combination; Anti-Bacterial Agents; Anti-Infective Agents, Urinary; beta-Lactamases; Biomarkers; Cefadroxil; Ceftibuten; Cefuroxime; Cephalexin; Cephalosporins; Ciprofloxacin; Disk Diffusion Antimicrobial Tests; Female; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Gram-Positive Bacteria; Gram-Positive Bacterial Infections; Humans; Linezolid; Middle Aged; Norfloxacin; Oxazolidinones; Time Factors; Trimethoprim, Sulfamethoxazole Drug Combination; Urinary Tract Infections

The duration of time that serum drug levels remain above the MIC (time above the MIC) for the pathogen has been shown to be the most significant parameter determining the efficacies of beta-lactam antibiotics. In the described study, we investigated the optimal time above the MIC of ceftibuten and cefaclor using a nonneutropenic mouse model of intra-abdominal infections caused by Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Streptococcus pneumoniae. The abilities of the drugs to protect mice against the organisms were determined in mouse protection tests, and the doses were fractionated to produce various dosing regimens with different times above the MIC. All drug-organism combinations showed a significant correlation (r > 0.9) between drug efficacy and the time above the MIC. Also, with ceftibuten treatment, the different dosing regimens that produced equal times above the MIC resulted in the same efficacy, whereas with cefaclor, an apparent dose-dependent effect was observed. These results showed that for a 100% recovery from K. pneumoniae and E. coli infections, the optimal times above the MIC with ceftibuten treatment were 2.2 and 1.6 h, respectively. Relatively high doses of both antibiotics were required to ensure recovery from S. pneumoniae infections. In vitro time-kill studies demonstrated that cefaclor exhibits a marked inoculum effect against the pathogens, and there was a concentration-dependent killing at a large inoculum size. On the other hand, ceftibuten showed no inoculum effect. It is suggested that optimization of both dose and time above the MIC appears to be necessary for the treatment of S. aureus infections with cefaclor, and this may apply to other beta-lactams tht exhibit marked inoculum effects.

Topics: Abdomen; Animals; Bacterial Infections; Cefaclor; Ceftibuten; Cephalosporins; Female; Gram-Negative Bacterial Infections; Gram-Positive Bacterial Infections; Half-Life; Mice; Time Factors