Urinary bactericidal activity of oral antibiotics against common urinary tract pathogens in an ex vivo model.
BACKGROUND
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.


METHODS
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.


RESULTS
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.


CONCLUSIONS
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.
Bedenic
Branka
B
Department of Microbiology, Medical School, University of Zagreb, Zagreb, Croatia. branka.bedenic@zg.htnet.hr
Topic
Marijana
M
Budimir
Ana
A
Bubonja
Marina
M
D000081:Acetamides / Q000008:administration & dosage; D000284:Administration, Oral; D000328:Adult; D000658:Amoxicillin / Q000008:administration & dosage; D019980:Amoxicillin-Potassium Clavulanate Combination / Q000008:administration & dosage; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D000892:Anti-Infective Agents, Urinary / Q000008:administration & dosage*; D015415:Biomarkers / Q000652:urine; D002434:Cefadroxil / Q000008:administration & dosage; D000077722:Ceftibuten; D002444:Cefuroxime / Q000008:administration & dosage; D002506:Cephalexin / Q000008:administration & dosage; D002511:Cephalosporins / Q000008:administration & dosage; D002939:Ciprofloxacin / Q000008:administration & dosage; D052978:Disk Diffusion Antimicrobial Tests; D005260:Female; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D016905:Gram-Negative Bacterial Infections / Q000188:drug therapy / Q000382:microbiology; D006094:Gram-Positive Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy / Q000382:microbiology; D006801:Humans; D000069349:Linezolid; D008875:Middle Aged; D009643:Norfloxacin / Q000008:administration & dosage; D023303:Oxazolidinones / Q000008:administration & dosage; D013997:Time Factors; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000008:administration & dosage; D014552:Urinary Tract Infections / Q000188:drug therapy* / Q000382:microbiology* / Q000652:urine; D001618:beta-Lactamases / Q000187:drug effects / Q000652:urine
D000081:Acetamides; D000900:Anti-Bacterial Agents; D000892:Anti-Infective Agents, Urinary; D015415:Biomarkers; D002511:Cephalosporins; D023303:Oxazolidinones; D002434:Cefadroxil; D002939:Ciprofloxacin; D019980:Amoxicillin-Potassium Clavulanate Combination; D000658:Amoxicillin; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D001618:beta-Lactamases; D000069349:Linezolid; D000077722:Ceftibuten; D009643:Norfloxacin; D002444:Cefuroxime; D002506:Cephalexin