["In vitro" activity of ten antimicrobial agents against anaerobic bacteria. A collaborative study, 1999-2002].
The antimicrobial activity of ampicillin, ampicillin-sulbactam, cefoxitin, ceftriaxone, imipenem, piperacillin, piperacillin-tazobactam, clindamycin, metronidazole, and azitromycin was assesed against 166 strains of anaerobic bacteria recovered from eight hospitals in Buenos Aires. The strains studied were Bacteroides fragilis group (65), Fusobacterium spp. (26), Prevotella spp. (21), Porphyromonas spp. (10), Clostridium difficile (10), other clostridia (12), and gram-positive cocci (22). The MICs were determined by the agar dilution method according to NCCLS document M11-A5. Metronidazole and piperacillin-tazobactam were the most active antimicrobial agents tested and exhibited MIC90 values of < or = 2 microg/ml and < or = 4 microg/ml against gram-negative organisms, and < or = 2 microg/ml, and < or = 8 microg/ml against gram-positive organisms, respectively. Among beta-lactams the activity against gram-negative rods was in the following order: imipenem > piperacillin > cefoxitin > ceftriaxone > ampicillin. Among the gram-positive bacteria the decreased activity was: piperacillin > imipenem > cefoxitin > ceftriaxone > ampicillin. The majority of the species studied showed different degrees of resistance to clindamycin and azitromycin. Nevertheless, 90% of Fusobacterium nucleatum and Porphyromonas spp. isolates were inhibited by 0.125 mg/ml of clindamycin and azitromycin, respectively.
Litterio
M
M
Hospital Nacional de Pediatría Juan P. Garrahan, Argentina mlitteri@garrahan.gov.ar
Bianchini
H
H
Carloni
G
G
Di Martino
A
A
Fernández Canigia
L
L
Greco
G
G
Legaria
C
C
Rollet
R
R
Rossetti
A
A
Predari
S C
SC
Castello
L
L
D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000145:classification / Q000494:pharmacology*; D001118:Argentina; D001421:Bacteria, Anaerobic / Q000187:drug effects* / Q000302:isolation & purification; D001424:Bacterial Infections / Q000382:microbiology; D003428:Cross Infection / Q000382:microbiology; D004305:Dose-Response Relationship, Drug; D024881:Drug Resistance, Bacterial; D024901:Drug Resistance, Multiple, Bacterial; D006089:Gram-Negative Anaerobic Bacteria / Q000187:drug effects / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000302:isolation & purification; D006801:Humans; D066298:In Vitro Techniques; D008826:Microbial Sensitivity Tests; D013045:Species Specificity
D000900:Anti-Bacterial Agents