Molecular characterization and antimicrobial susceptibilities of extra-intestinal Clostridium difficile isolates

Amongst 25 extra-intestinal clinical isolates of Clostridium difficile, A(+)B(+) (72%) and A(-)B(+) (4%) toxigenic phenotypes, as well as the non-toxigenic phenotype (A(-)B(-)) (24%), were identified. The A(-)B(-) isolates did not express toxin, yet carried part of the tcdA and tcdB gene and are of a previously unreported toxinotype. Six A(+)B(+) isolates also carried binary toxin genes. Resistance to erythromycin (20%), clindamycin (48%), tetracycline (16%), moxifloxacin (16%) and imipenem (11%) occurred but with no apparent correlation to phenotype. None of the strains was resistant to vancomycin or metronidazole. Imipenem-resistance decreased by EDTA, but susceptibility to meropenem suggests the presence of an imipenem specific metalloenzyme.

United States National Hospital Survey of anaerobic culture and susceptibility methods, II

To assess the status of clinical anaerobic bacteriology in the United States, we surveyed (by means of a questionnaire) 120 hospitals selected at random with bed capacities of 200-1000, and we received responses from 78 (65%), all of which performed some degree of clinical anaerobic microbiology. Separate anaerobic blood culture bottles were used by 73 labs (94%) (median, 450 specimens/mo): 56% used Bactec 7, 27 or 37; 15% used 'BacT-Alert'; 11% used Columbia broth; 5% used thioglycolate and 'lytic'; 3% each used, Dupont Isolator, Supplemented peptone or other media. Selective media was used for primary anaerobe isolation by 89% labs which included: LKV, 76%; PEA, 53%; BBE, 31%; CNA, 28%; 'CDC', 12%. Sixty labs (78%) stored anaerobes after isolation (median 7 days), most using blood agar plates (31%), chopped meat (26%) or thioglycolate broth (27%) either for further identification (30 out of 78) or susceptibility testing (33 out of 78), if clinically indicated. Only 23% performed routine anaerobic susceptibility testing of clinical isolates. Of the 77% that do not perform susceptibility studies, 59% would not even perform them upon physician request; 30% relied on published surveys; 68% did not publish results of anaerobic susceptibility in annual summaries. When susceptibility testing was performed, the test agents selected were related to availability on a commercial system (21), NCCLS recommendation (20), hospital formulary (15) or hospital committee input (20). Nine of 78 labs (12%) had discussed stopping or decreasing the performance of both anaerobic bacteriology and susceptibility testing. Despite educational and published guidelines, clinical anaerobic bacteriology is not uniformly practiced and could be improved. In addition, an educational effort must be made in order to stress the relevance and increase performance of anaerobic bacteriology.

Identification and strain differentiation of 'Bacteroides fragilis group' species and Prevotella bivia by PCR fingerprinting

Using single consensus primers of genomic nucleotide sequences, PCR-generated fingerprints were used for identification and differentiation of the Bacteroides fragilis group (B. fragilis, B. thetaiotaomicron, B. ovatus, B. distasonis, B. vulgatus) and Prevotella bivia (B. bivius) by comparing the DNA profiles with those of reference strains from the American Type Culture Collection and German Culture Collection. When primed by a single primer phage M13 core sequence, intra-species specific differences and species-specific bands were detected. Using primers derived from the evolutionarily conserved tRNA gene sequence, species-specific patterns were produced. A computer program, GelManager, was used to analyze the profiles and generate dendrograms. The correlation coefficients determined from the DNA fingerprint profiles of the clinical isolates (using the M13 core primer) fell within a narrow range, reflecting a high level of homology within the species. Based on the dendrograms, strains of one species were clearly differentiated from strains of other species. For comparison, SDS-PAGE analysis of whole cell extracts was also performed to obtain protein band patterns of various strains. Because of the simplicity of the PCR fingerprinting method and the ease of performance of computerized evaluation of data, this technique is a useful method for both species and strain differentiation, as well as for characterization of Bacteroides species and Prevotella bivia.

Human serum activity of telithromycin, azithromycin and amoxicillin/clavulanate against common aerobic and anaerobic respiratory pathogens

Telithromycin is a new ketolide antimicrobial with a good in vitro activity against both aerobic and anaerobic respiratory pathogens. In this study, we evaluated the antibacterial activity over time of telithromycin (800mg), azithromycin (500mg), and amoxicillin/clavulanate (875/125mg) in serum following single oral doses of these agents to 10 healthy subjects. Inhibitory and bactericidal titers were determined at 2, 6, 12, and 24h after each dose and the median titer was used to determine antibacterial activity. Against two azithromycin-resistant strains of Streptococcus pneumoniae, both telithromycin (MIC=0.25 and 0.5 microg/mL) and amoxicillin/clavulanate exhibited inhibitory and cidal activity for at least 6h. All three antibiotics provided prolonged (>or=12h) inhibitory activity against strains of Hemophilus influenzae (telithromycin MIC=4.0 microg/ml). Both telithromycin and amoxicillin/clavulanate exhibited rapid and prolonged inhibitory activity (>or=12h) against each of the anaerobes studied (Finegoldia [Peptostreptococcus] magna Peptostreptococcus micros, Prevotella bivia, and Prevotella melaninogenica). Moreover, both agents provided bactericidal activity against both Prevotella species. In this ex vivo pharmacodynamic study, we found that telithromycin provided rapid and prolonged antibacterial activity in serum against macrolide-resistant strains of S. pneumoniae, beta-lactamase-positive and -negative strains of H. influenzae, and common respiratory anaerobic pathogens. These findings suggest that telithromycin could have clinical utility in the treatment of community-acquired mixed aerobic-anaerobic respiratory tract infections, including chronic sinusitis and aspiration pneumonia.

In vitro activities of daptomycin, ciprofloxacin, and other antimicrobial agents against the cells and spores of clinical isolates of Bacillus species

Daptomycin inhibited 67 of 70 clinical isolates of Bacillus species at < or =1 microg/ml and 100% of them at < or =2 microg/ml. It showed bactericidal activity similar to that of ciprofloxacin against vegetative cells but not against spores. For 2 strains, the ciprofloxacin MICs were >4 g/ml, and 10 strains were resistant to erythromycin.

Synergistes group organisms of human origin

The bacterial division Synergistes represents a poorly characterized phylotype of which only a few isolates have been cultured, primarily from natural environments. Recent detection of Synergistes-like sequence types in periodontal pockets and caries lesions of humans prompted us to search the R. M. Alden culture collection (Santa Monica, Calif.) for biochemically unidentifiable, slow-growing, obligately anaerobic gram-negative bacilli. Here we report on five clinical isolates cultured from peritoneal fluid and two isolates from soft-tissue infections that together constitute three separate evolutionary lineages within the phylogenetic radiation of the division Synergistes. One of these clusters was formed by the peritoneal isolates and had an 85% similarity to Synergistes jonesii, the first described Synergistes species, which was isolated from the rumen of a goat. The isolates from soft-tissue infections, on the other hand, formed two distinct lineages moderately related to each other with a similarity of approximately 78%. In addition, by using a newly designed 16S rRNA gene-based PCR assay with intended target specificity for Synergistes, we found that the dominant phylotype from a fecal sample was nearly identical to that of the strains obtained from peritonitis. Conversely, sequence types detected in periodontal pockets formed a separate cluster that shared a similarity of only 80% with the soft-tissue isolates. These findings suggest a high diversity of medically important Synergistes clades that apparently are unique to individual ecological niches in the human body. In conclusion, we now have available the first characterized human isolates of the division Synergistes which are colonizing, and probably infecting, several sites in the human body.

Clostridium aldenense sp. nov. and Clostridium citroniae sp. nov. isolated from human clinical infections

One hundred eight isolates were previously identified in our laboratory as Clostridium clostridioforme by colonial and cellular morphology, as well as biochemical tests. Recent studies have indicated that there are actually three different species in this C. clostridioforme group: C. hathewayi, C. bolteae, and C. clostridioforme. Our isolates were reexamined using biochemical and enzymatic tests and molecular methods. Forty-six isolates were reidentified as C. hathewayi, 34 as C. bolteae, five as C. clostridioforme, and one as C. symbiosum. Twenty-two strains were identified only to the genus level by 16S rRNA gene sequencing, and although they are microscopically and morphologically indistinguishable from the above-mentioned three species, they are phenotypically different and only 96 to 98% similar by gene sequencing. Twenty of these 22 strains were indole positive and formed two novel species. We propose Clostridium aldenense sp. nov. and Clostridium citroniae sp. nov. as names for these new species. They are differentiated from each other by results for raffinose, rhamnose, alpha-galactosidase, and beta-galactosidase: positive, negative, positive, and positive, respectively, for the former species and negative, positive, negative, and negative, respectively, for the latter species. The type strain of C. aldenense is RMA 9741 (ATCC BAA-1318; CCUG 52204), and the type strain of C. citroniae is RMA 16102 (ATCC BAA-1317; CCUG 52203).

In vitro activities of dalbavancin and 12 other agents against 329 aerobic and anaerobic gram-positive isolates recovered from diabetic foot infections

Tests of dalbavancin's in vitro activity against 209 aerobic and 120 anaerobic isolates from pretreatment diabetic foot infections showed an MIC(90) of < or =0.125 microg/ml against methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA), and 120 anaerobes (Clostridium perfringens, other clostridia, Peptoniphilus asaccharolyticus, Finegoldia magna, and Anaerococcus prevotii), compared to respective MIC(90)s for MSSA and MRSA of 0.5 and 1 microg/ml for vancomycin, 4 and 4 microg/ml for linezolid, 0.5 and 0.5 microg/ml for daptomycin, and 0.25 and >8 microg/ml for clindamycin.

In vitro activities of daptomycin, vancomycin, and penicillin against Clostridium difficile, C. perfringens, Finegoldia magna, and Propionibacterium acnes

Daptomycin has in vitro activity against gram-positive anaerobic bacteria, although limited numbers of species have been tested. We studied the in vitro activities of daptomycin, vancomycin, and penicillin against more than 100 strains each of Clostridium difficile, C. perfringens, Finegoldia magna, and Propionibacterium acnes. Daptomycin Etest MICs and results from time-kill studies were determined for selected strains. For 392 of 421 strains (93%), daptomycin was inhibitory at < or =1 microg/ml, including 15 of 16 strains of C. difficile with elevated linezolid MICs of 8 and 16 microg/ml, all 32 strains with moxifloxacin MICs of > or =4 microg/ml, and all 16 strains resistant to clindamycin. Daptomycin MICs were also < or =1 microg/ml for all 16 F. magna strains resistant to clindamycin and all 32 strains resistant to tetracycline. Only one strain, a C. perfringens strain, had a MIC of >2 microg/ml to daptomycin. Eighty-five and 92.5% of the Etest MICs were within 1 dilution of the agar dilution method for all drugs at 24 and 48 h, respectively. In time-kill studies, a C. difficile strain was inhibited by both daptomycin and vancomycin at 1, 2, 4, 8, and 24 h; colony counts were decreased by 2.3 to 2.9 log at 24 h. Vancomycin was not bactericidal for C. perfringens; however, daptomycin showed bactericidal activity as early as 1 h at four and eight times the MIC and at 2 and 4 h at two and four times the MIC.

In vitro activity of ceftobiprole against aerobic and anaerobic strains isolated from diabetic foot infections

Against 443 aerobic and anaerobic bacteria isolated from diabetic foot infections, ceftobiprole MICs (microg/ml) at which 90% of the isolates tested were inhibited were as follows: methicillin-resistant Staphylococcus aureus, 1; methicillin-susceptible S. aureus and Staphylococcus lugdunensis, 0.5; Anaerococcus prevotii, 0.125; Finegoldia magna, 0.5; Peptoniphilus asaccharolyticus, 1; Peptostreptococcus anaerobius, 4; Escherichia coli and Enterobacter species, 0.125; Klebsiella species, 2; and Pseudomonas aeruginosa, 8.

In vitro activity of azithromycin and nine comparator agents against 296 strains of oral anaerobes and 31 strains of Eikenella corrodens

At this time in the USA there are no antimicrobials with specific indications for oral infections, and many of those currently used have limited efficacy against oral anaerobic strains. We tested the activity of azithromycin against a broad range of anaerobic oral pathogens and, at pH 8, found it to be effective against 98% of strains, including all fusobacteria and beta-lactamase-producing strains of Prevotella spp. All strains of Eikenella corrodens were also susceptible to azithromycin but resistant to erythromycin, clindamycin, metronidazole and cefalexin. Other comparator agents were penicillin, amoxicillin/clavulanic acid, tetracycline, levofloxacin and ciprofloxacin. Minimum inhibitory concentrations obtained on agar adjusted to pH 8 were generally one dilution lower than those obtained on agar at pH 7.

Comparative in vitro susceptibilities of 396 unusual anaerobic strains to tigecycline and eight other antimicrobial agents

Tigecycline was tested against 396 strains of lesser-known anaerobic species encountered in human infections. It was active against all gram-positive strains and 228 of 232 gram-negative anaerobes at < or =1 microg/ml. One strain of Prevotella oralis was nonsusceptible at 8 microg/ml.

Pelvic abscess due to Ochrobactrum intermedium [corrected] in an immunocompetent host: case report and review of the literature

Ochrobactrum intermedium [corrected] infection is rare in humans and is generally associated with immunocompromised hosts with indwelling foreign bodies. We report a case of pelvic abscess with O. intermedium [corrected] after a routine appendectomy in an immunocompetent patient and review the literature on O. intermedium [corrected] infection in patients with normal immune function.

In vitro activity of 11 antibiotics against 74 anaerobes isolated from pediatric intra-abdominal infections

The in vitro activity of 11 antimicrobials was tested against 74 recent anaerobic isolates obtained from pretreatment cultures in pediatric patients with complicated intra-abdominal infections using the CLSI M11-A-6 agar dilution method. Carbapenems, beta-lactamase inhibitor combinations and metronidazole retained good activity, while all Bacteroides fragilis group species produced beta-lactamase and were penicillin resistant and 43% were either intermediately susceptible or resistant to clindamycin. Cefoxitin had moderate activity against B. fragilis but poor activity against Bacteroides thetaiotaomicron and other B. fragilis group isolates.

In vitro activity of moxifloxacin against 923 anaerobes isolated from human intra-abdominal infections

The in vitro activity of moxifloxacin against 923 recent anaerobic isolates obtained from pretreatment cultures in patients with complicated intra-abdominal infections was studied using the CLSI M11-A-6 agar dilution method. Moxifloxacin was active against 87% (96 of 110) Bacteroides fragilis strains at < or = 1 microg/ml and 87% (79 of 90) B. thetaiotaomicron strains at < or = 2 microg/ml. Species variation was seen, with B. uniformis, B. vulgatus, Clostridium clostridioforme, and C. symbiosum being least susceptible and accounting for most of the resistant isolates; excluding the aforementioned four resistant species, 86% (303 of 363) of Bacteroides species isolates and 94% (417 of 450) of all other genera and species were susceptible to < or = 2 microg/ml of moxifloxacin. Overall, moxifloxacin was active against 763 of 923 (83%) of strains at < or = 2 microg/ml, supporting its use as a monotherapy for some community-acquired intra-abdominal infections.

Comparative in vitro activities of retapamulin (SB-275833) against 141 clinical isolates of Propionibacterium spp., including 117 P. acnes isolates

Using the NCCLS agar dilution method, we studied the in vitro activity of retapamulin (SB-275833) against 141 clinical isolates of Propionibacterium species, including seven multiresistant strains, and found retapamulin to be the most active agent among those tested with MICs of < or = 1 microg/ml against all isolates.

Ertapenem versus piperacillin/tazobactam for diabetic foot infections (SIDESTEP): prospective, randomised, controlled, double-blinded, multicentre trial

BACKGROUND

Diabetic foot infections are a common and serious problem, yet few randomised trials of adequate quality have compared the efficacy of the various antibiotic regimens available for their treatment. Our aim was to assess the efficacy and safety of ertapenem versus piperacillin/tazobactam for foot infections.

METHODS

We did a randomised, double-blinded, multicentre trial in adults (n=586) with diabetes and a foot infection classified as moderate-to-severe and requiring intravenous antibiotics. We assigned patients intravenous ertapenem (1 g daily; n=295) or piperacillin/tazobactam (3.375 g every 6 h; n=291) given for a minimum of 5 days, after which oral amoxicillin/clavulanic acid (875/125 mg every 12 h) could be given for up to 23 days. Investigators retained the option to administer vancomycin to patients in either group to ensure adequate coverage for potentially antibiotic resistant Enterococcus spp and meticillin-resistant Staphylococcus aureus (MRSA). Our primary outcome was the proportion of patients with a favourable clinical response (cure or improvement) on the day that intravenous antibiotic was discontinued. Analyses were by an evaluable-patient only approach. This study is registered with , number NCT00229112.

FINDINGS

Of the 576 patients treated, 445 were available for assessment at the end of intravenous therapy. Both baseline characteristics and favourable clinical response rates were similar for the 226 who received ertapenem and the 219 who received piperacillin/tazobactam (94%vs 92%, respectively; between treatment difference 1.9%, 95% CI -2.9 to 6.9). Rates of favourable microbiological responses (eradication rates and clinical outcomes, by pathogen) and adverse events did not differ between groups.

INTERPRETATION

Clinical and microbiological outcomes for patients treated with ertapenem were equivalent to those for patients treated with piperacillin/tazobactam, suggesting that this once-daily antibiotic should be considered for parenteral therapy of diabetic foot infections, when deemed appropriate.

Biochemical differentiation and comparison of Desulfovibrio species and other phenotypically similar genera

Seventeen human clinical isolates representing four species of Desulfovibrio were characterized using 16S rRNA gene sequences and tests for catalase, indole, nitrate, bile, urease, formate-fumarate stimulation, desulfoviridin, motility, and hydrogen sulfide production, plus susceptibility to antimicrobial agents. Eighty additional strains representing 10 phenotypically similar genera (Bilophila, Selenomonas, Capnocytophaga, Campylobacter, Bacteroides, Sutterella, Anaerobiospirillum, Dialister, Veillonella, and Mobiluncus) were included for comparison. All Desulfovibrio species produced H2S and were desulfoviridin positive, and all Desulfovibrio species except D. piger were motile. The four Desulfovibrio species could be distinguished from each other using tests for catalase, indole, nitrate, urease, and growth on bile, with the following results (positive [+], negative [-], growth [G], and no growth [NG]): for D. piger, -, -, -, -, and G, respectively; for D. fairfieldensis, +, -, +, -, and G, respectively; for D. desulfuricans, -, -, +, +, and NG, respectively; and for D. vulgaris, -, +, -, -, and G, respectively. Resistance to the 10-microg colistin disk separated the Desulfovibrio species from most of the other genera, which were usually susceptible. These simple tests were useful for characterizing the Desulfovibrio species and differentiating them from other phenotypically similar genera.

Characterization of the Bacteroides fragilis pathogenicity island in human blood culture isolates

Bacteroides fragilis is an important anaerobic pathogen accounting for up to 10% of bacteremias in adult patients. Enterotoxin producing B. fragilis (ETBF) strains have been identified as enteric pathogens of children and adults. In order to further characterize the B. fragilis pathogenicity island (BfPAI) and using PCR assays for bft- and mpII-metalloprotease genes, we determined the frequency of B. fragilis strains with pattern I (containing the BfPAI and its flanking region), pattern II (lacking both the BfPAI and the flanking region), and pattern III (lacking the BfPAI but containing the flanking region) in 63 blood culture isolates. The results were compared to 197 B. fragilis isolates from different clinical sources. We found 19% of blood culture isolates were pattern I (ETBF), 43% were pattern II (NTBF) and 38% were pattern III (NTBF). Comparatively, B. fragilis isolates from other clinical sources were 10% pattern I, 47% pattern II and 43% pattern III. This suggests that the pathogenicity island and the flanking elements may be general virulence factors of B. fragilis.

Broth microdilution and disk diffusion tests for susceptibility testing of Pasteurella species isolated from human clinical specimens

Broth microdilution and disk diffusion susceptibility testing were performed on 73 strains of Pasteurella species isolated from human infections and on five American Type Culture Collection strains of Pasteurella species. Both methods appear reliable for testing susceptibilities of Pasteurella species.

In vitro activities of tinidazole and metronidazole against Clostridium difficile, Prevotella bivia and Bacteroides fragilis

Tinidazole, a 5-nitroimidazole similar to metronidazole, was studied against 40 Clostridium difficile, 10 Prevotella bivia and 11 Bacteroides fragilis clinical isolates. The geometric mean MICs of tinidazole and metronidazole were, respectively: C. difficile, 0.31 and 0.28 microg/mL; P. bivia, 2.33 and 1.52 microg/mL; B. fragilis, 0.5 and 0.71 microg/mL.

16S-23S rRNA gene internal transcribed spacer sequences for analysis of the phylogenetic relationships among species of the genus Porphyromonas

The 16S-23S rRNA gene internal transcribed spacer (ITS) regions of 11 reference strains of Porphyromonas species, together with Bacteroides distasonis and Tannerella forsythensis, were analysed to examine interspecies relationships. Compared with the phylogenetic tree generated using 16S rRNA gene sequences, the resolution of the ITS sequence-based tree was higher, but species positioning and clustering were similar with both approaches. The recent separation of Porphyromonas gulae and Porphyromonas gingivalis into distinct species was confirmed by the ITS data. In addition, analysis of the ITS sequences of 24 clinical isolates of Porphyromonas asaccharolytica plus the type strain ATCC 25260(T) divided the sequences into two clusters, of which one was alpha-fucosidase-positive (like the type strain) while the other was alpha-fucosidase-negative. The latter resembled the previously studied unusual extra-oral isolates of 'Porphyromonas endodontalis-like organisms' (PELOs) which could therefore be called 'Porphyromonas asaccharolytica-like organisms' (PALOs), based on the genetic identification. Moreover, the proposal of alpha-fucosidase-negative P. asaccharolytica strains as a new species should also be considered.

Pharmacokinetics and Pharmacodynamics of Linezolid in Obese Patients with Cellulitis

BACKGROUND:

Linezolid is an oxazolidinone antimicrobial with excellent oral bioavailability and tissue penetration and is active against multidrug-resistant skin/soft tissue pathogens.

OBJECTIVE:

To study the pharmacokinetics and antibacterial activity of linezolid against selective skin/soft tissue pathogens in obese patients.

METHODS:

We obtained multiple serum samples from 7 obese patients (>50% over their calculated ideal body weight) receiving oral linezolid 600 mg every 12 hours for treatment of cellulitis. Following a minimum of 3 doses, serum concentrations of linezolid were measured in each subject prior to (trough) and 1 and 6 hours after a dose. These samples were then tested against clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) (linezolid minimum inhibitory concentrations [MICs] 1.0, 2.0, 4.0 μg/mL) and one strain each of vancomycin-resistant Enterococcus faecium (VRE) (MIC 2.0 μg/mL), Bacteroides fragilis (MIC 2.0 μg/mL), and Peptostreptococcus magnus (MIC 1.0 μg/mL). Serum inhibitory titers (SITs) and bactericidal titers (SBTs) were measured at each time point, and the median activity for these 7 patients was calculated.

RESULTS:

Mean linezolid serum concentrations were 4.2, 12.3, and 7.2 μg/mL at these respective time points. Median SITs for 12 hours (100% of the dosing interval) were observed against each organism with the exception of the least susceptible strain of MRSA (MIC 4.0 μg/mL); serum inhibitory activity was observed only at the one-hour time point against this isolate. Furthermore, prolonged (⩾6 h) median SBTs were observed against one isolate of MRSA (MIC 1.0 μg/mL) as well as the strain of VRE and P. magnus.

CONCLUSIONS:

Serum concentrations of oral linezolid in this patient population were diminished compared with those of healthy volunteers, but still provided prolonged serum inhibitory activity against common pathogens associated with skin/soft tissue infections. One treatment concern would be an obese patient receiving oral linezolid who was infected with a less susceptible (MIC ⩾4.0 μg/mL) strain of S. aureus. Bactericidal activity was also observed against selective pathogens.

Comparative in vitro activities of XRP 2868, pristinamycin, quinupristin-dalfopristin, vancomycin, daptomycin, linezolid, clarithromycin, telithromycin, clindamycin, and ampicillin against anaerobic gram-positive species, actinomycetes, and lactobacilli

A comparative study of the in vitro activities of XRP 2868, a new oral streptogramin, against 266 anaerobic gram-positive clinical isolates using the agar dilution method showed that the XRP 2868 MICs for 95% (254 of 266) of isolates were < or =0.5 microg/ml. XRP 2868 MICs for only two strains, one being Clostridium clostridioforme (MIC, 16 microg/ml) and the other being Clostridium difficile (MIC, 32 microg/ml), were >2 microg/ml. Depending on its pharmacokinetics and pharmacodynamics, XRP 2868 has potential for use against infections with gram-positive anaerobes and deserves further clinical evaluation.

Genetic determinant of intrinsic quinolone resistance in Fusobacterium canifelinum

Fourteen fluoroquinolone-resistant fusobacterial strains, originating from cats or dogs, were characterized by sequencing of the 16S-23S and 16S rRNA genes and DNA-DNA hybridization and were described as a new species, Fusobacterium canifelinum. All of the strains are intrinsically resistant (MIC, >4 g/ml) to levofloxacin and other fluoroquinolones. Compared to the quinolone resistance-determining region (gyrA) of the susceptible relative F. nucleatum, we found that Ser79 was replaced with leucine and Gly83 was replaced with arginine.

In vitro activity of oritavancin (LY333328), vancomycin, clindamycin, and metronidazole against Clostridium perfringens, Propionibacterium acnes, and anaerobic Gram-positive cocci

Using an agar dilution method, we determined the in vitro activity of oritavancin, vancomycin, clindamycin and metronidazole against 114 unique clinical isolates of Gram-positive anaerobes. MIC(90)s (microg/mL) for oritavancin were as follows: Clostridium perfringens 1.0, Propionibacterium acnes 0.25, Peptostreptococcus anaerobius 0.25, Peptoniphilus asaccharolyticus 0.5, Finegoldia magna 0.25, Micromonas. micros 0.25, and Anaerococcus prevotii 0.25. On a weight basis, oritavancin is slightly more active than vancomycin against the strains tested. The oritavancin MICs are comparable to those previously reported against staphylococci and enterococci. Oritavancin shows excellent potential for treatment of infections containing Gram-positive anaerobes such as these.

Fusobacterium canifelinum sp. nov., from the oral cavity of cats and dogs

Fourteen strains of Gram-negative, anaerobic, fluoroquinolone-resistant, non-sporulating rods were isolated from various infections in cats and dogs, as well as from wounds in humans after cat- or dog-bites. These strains were characterized by sequencing of the 16S-23S rDNA internal transcribed spacer (ITS) regions, 16S rDNA, DNA-DNA hybridization, phylogenetic analysis, and phenotypic tests. The results indicate that the novel strains belong to a distinct species, closely related to Fusobacterium nucleatum. The species Fusobacterium canifelinum sp. nov. is proposed, with strain ATCC BAA 689T as the type strain.

In vitro activities of iodonium salts against oral and dental anaerobes

The comparative in vitro activities of 11 iodonium salt compounds, 0.12% chlorhexidine, and four antimicrobial agents against 322 anaerobic and fastidious potential dental and periodontal bacterial pathogens were studied. Iodonium salts 3, 4, 5, 9, and 10 had in vitro activities comparable to that of chlorhexidine against most isolates. These compounds may be suitable for incorporation into an oral mouthwash.

Bacteriology of a bear bite wound to a human: case report

Human contact with bears has become more frequent, as has the resultant bear maulings and bite injuries. We report the bacteriology of a patient bitten by a grizzly bear (Ursus arctos) from the Rocky Mountains foothills area east of Banff National Park, Alberta, Canada. The patient received field care, including metronidazole and cefazolin. Subsequent deep-wound cultures grew Serratia fonticola, Serratia marcescens, Aeromonas hydrophila, Bacillus cereus, and Enterococcus durans but no anaerobes.

Evaluation of the Velogene genomic assay for detection of vanA and vanB genes in vancomycin-resistant Enterococcus species

The Velogene (VEL) genomic assay is a qualitative DNA probe for vanA and vanB in enterococci. 150 clinical isolates were tested with the VEL assay and characterized by pigment production, catalase levels, motility, growth in 6 micro g of vancomycin/ml, vancomycin and teicoplanin susceptibility, API 20S assay, and genotyping by multiplex PCR. The VEL assay identified all enterococcal strains with vanA and vanB genes.

In vitro activities of the new semisynthetic glycopeptide telavancin (TD-6424), vancomycin, daptomycin, linezolid, and four comparator agents against anaerobic gram-positive species and Corynebacterium spp

Telavancin is a new semisynthetic glycopeptide anti-infective with multiple mechanisms of action, including inhibition of bacterial membrane phospholipid synthesis and inhibition of bacterial cell wall synthesis. We determined the in vitro activities of telavancin, vancomycin, daptomycin, linezolid, quinupristin-dalfopristin, imipenem, piperacillin-tazobactam, and ampicillin against 268 clinical isolates of anaerobic gram-positive organisms and 31 Corynebacterium strains using agar dilution methods according to National Committee for Clinical Laboratory Standards procedures. Plates with daptomycin were supplemented with Ca(2+) to 50 mg/liter. The MICs at which 90% of isolates tested were inhibited (MIC(90)s) for telavancin and vancomycin were as follows: Actinomyces spp. (n = 45), 0.25 and 1 microg/ml, respectively; Clostridium difficile (n = 14), 0.25 and 1 microg/ml, respectively; Clostridium ramosum (n = 16), 1 and 4 microg/ml, respectively; Clostridium innocuum (n = 15), 4 and 16 microg/ml, respectively; Clostridium clostridioforme (n = 15), 8 and 1 microg/ml, respectively; Eubacterium group (n = 33), 0.25 and 2 microg/ml, respectively; Lactobacillus spp. (n = 26), 0.5 and 4 microg/ml, respectively; Propionibacterium spp. (n = 34), 0.125 and 0.5 microg/ml, respectively; Peptostreptococcus spp. (n = 52), 0.125 and 0.5 microg/ml, respectively; and Corynebacterium spp. (n = 31), 0.03 and 0.5 microg/ml, respectively. The activity of TD-6424 was similar to that of quinupristin-dalfopristin for most strains except C. clostridioforme and Lactobacillus casei, where quinupristin-dalfopristin was three- to fivefold more active. Daptomycin had decreased activity (MIC > 4 microg/ml) against 14 strains of Actinomyces spp. and all C. ramosum, Eubacterium lentum, and Lactobacillus plantarum strains. Linezolid showed decreased activity (MIC > 4 microg/ml) against C. ramosum, two strains of C. difficile, and 15 strains of Lactobacillus spp. Imipenem and piperacillin-tazobactam were active against >98% of strains. The MICs of ampicillin for eight Clostridium spp. and three strains of L. casei were >1 microg/ml. The MIC(90) of TD-6424 for all strains tested was Collapse

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MESH Headings

• Adult
• Aminoglycosides/pharmacology
• Anti-Bacterial Agents/pharmacology
• Bacteria, Aerobic/drug effects
• Bacteria, Anaerobic/drug effects
• Corynebacterium/drug effects
• Gram-Positive Bacteria/drug effects
• Gram-Positive Bacterial Infections/microbiology
• Humans
• Lipoglycopeptides
• Microbial Sensitivity Tests

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Clostridium innocuum bacteremia secondary to infected hematoma with gas formation in a kidney transplant recipient

Clostridium innocuum is a relatively antimicrobial resistant, frequently misidentified anaerobe that has only rarely been associated with bacteremia. A 38-year-old female with chronic hepatitis C underwent a second kidney transplant operation. Two weeks after surgery a computed tomography scan of the abdomen showed a heterogeneous hematoma with pockets of gas adjacent to the allograft, which extended into the pelvis and left abdominal wall, associated with low-grade fever. An anaerobic blood culture grew a Clostridium initially identified as C. subterminale and later re-identified as C. innocuum. At abdominal exploration liquefied blood was evacuated, and the patient completed a course of antibiotics and recovered. C. innocuum should be considered as a cause of gas-producing anaerobic infection in transplant patients. Because C. innocuum is frequently misidentified by the use of commercial anaerobic identification kits, its true incidence in serious infections is likely underestimated.

Clinical Presentation and Bacteriologic Analysis of Infected Human Bites in Patients Presenting to Emergency Departments

Previous studies of infected human bites have been limited by small numbers of patients and suboptimal microbiologic methodology. We conducted a multicenter prospective study of 50 patients with infected human bites. Seventy percent of the patients and assailants were young adult men. Fifty-six percent of injuries were clenched-fist injuries and 44% were occlusional bites. Most injuries were to the hands. Fifty-four percent of patients were hospitalized. The median number of isolates per wound culture was 4 (3 aerobes and 1 anaerobe); aerobes and anaerobes were isolated from 54% of wounds, aerobes alone were isolated from 44%, and anaerobes alone were isolated from 2%. Isolates included Streptococcus anginosus (52%), Staphylococcus aureus (30%), Eikenella corrodens (30%), Fusobacterium nucleatum (32%), and Prevotella melaninogenica (22%). Candida species were found in 8%. Fusobacterium, Peptostreptococcus, and Candida species were isolated more frequently from occlusional bites than from clenched-fist injuries. Many strains of Prevotella and S. aureus were beta-lactamase producers. Amoxicillin-clavulanic acid and moxifloxacin demonstrated excellent in vitro activity against common isolates.

In vitro activities of ABT-492, a new fluoroquinolone, against 155 aerobic and 171 anaerobic pathogens isolated from antral sinus puncture specimens from patients with sinusitis

ABT-492 exhibited excellent in vitro activities against all 326 aerobic and anaerobic antral puncture sinus isolates tested with MICs (in micrograms per milliliter) at which 90% of the isolates tested were inhibited as follows: Haemophilus influenzae, 0.001; Moraxella catarrhalis, 0.008; and Streptococcus pneumoniae, 0.015. It was four- to sixfold more active than other fluoroquinolones, including against levofloxacin-resistant strains of S. pneumoniae, methicillin-resistant Staphylococcus aureus, and Prevotella species.

In vitro activities of ramoplanin, teicoplanin, vancomycin, linezolid, bacitracin, and four other antimicrobials against intestinal anaerobic bacteria

By using an agar dilution method, the in vitro activities of ramoplanin, teicoplanin, vancomycin, linezolid, and five other agents were determined against 300 gram-positive and 54 gram-negative strains of intestinal anaerobes. Ramoplanin was active at <or=2 microg/ml against 287 of 300 (95.7%) gram-positive organisms, including 18 strains of Clostridium difficile for which MICs of ramoplanin were 0.25 to 0.5 microg/ml; for 3 of these, linezolid MICs were 8 to 16 micro g/ml. Nineteen Clostridium innocuum strains for which the vancomycin MIC at which 90% of strains were inhibited was 16 microg/ml were susceptible to ramoplanin at 0.06 to 0.25 microg/ml and to teicoplanin at 0.125 to 1.0 microg/ml. All strains of Eubacterium, Actinomyces, Propionibacterium, and Peptostreptococcus spp. were inhibited by <or=0.25 microg of ramoplanin per ml and <or=1 microg of vancomycin per ml. Ramoplanin was also active at <or=4 microg/ml against 15 of 22 of the Prevotella and Porphyromonas strains tested, but ramoplanin MICs for all 31 strains of the Bacteroides fragilis group, the Fusobacterium mortiferum-Fusobacterium varium group, and Veillonella spp. were >or=256 microg/ml. Ramoplanin displays excellent activity against C. difficile and other gram-positive enteric anaerobes, including vancomycin-resistant strains; however, it has poor activity against most gram-negative anaerobes and thus potentially has a lesser effect on the ecological balance of normal fecal flora.

Desulfovibrio desulfuricans bacteremia and review of human Desulfovibrio infections

One case of primary Desulfovibrio desulfuricans bacteremia in an immunocompetent man is presented, and 15 other reported cases are reviewed. While most isolates have not been identified to the species level, Desulfovibrio fairfieldensis and D. desulfuricans have been associated with incidents of bacteremia and D. vulgaris has been associated with intra-abdominal infections. In vitro studies suggest that empirical therapy with either imipenem or metronidazole should be considered.

In vitro activities of telithromycin and 10 oral agents against aerobic and anaerobic pathogens isolated from antral puncture specimens from patients with sinusitis

A study of the comparative in vitro activity of telithromycin, a new ketolide, against 155 aerobic and 171 anaerobic antral sinus puncture isolates showed it to be active against a broad range of sinus pathogens. All pneumococci, including erythromycin-resistant strains, were susceptible to telithromycin at < or = 0.5 microg/ml; all Haemophilus influenzae and Eikenella corrodens strains were inhibited by < or = 4 microg of telithromycin/ml; all Moraxella spp. and beta-lactamase-producing Prevotella species strains were inhibited by < or = 0.25 and 0.5 microg of telithromycin/ml, respectively. Among all anaerobes tested, 94% (160 of 171 strains) were susceptible to < or = 4 microg of telithromycin/ml; however, 8 of 17 (47%) Fusobacterium strains, 2 Veillonella strains, and 1 Peptostreptococcus micros strain required > 4 microg of telithromycin/ml for inhibition. Telithromycin may offer a therapeutic alternative for sinus infections, including those due to erythromycin-resistant pneumococci.

In vitro activities of dalbavancin and nine comparator agents against anaerobic gram-positive species and corynebacteria

Dalbavancin is a novel semisynthetic glycopeptide with enhanced activity against gram-positive species. Its comparative in vitro activities and those of nine comparator agents, including daptomycin, vancomycin, linezolid, and quinupristin-dalfopristin, against 290 recent gram-positive clinical isolates strains, as determined by the NCCLS agar dilution method, were studied. The MICs of dalbavancin at which 90% of various isolates tested were inhibited were as follows: Actinomyces spp., 0.5 microg/ml; Clostridium clostridioforme, 8 microg/ml; C. difficile, 0.25 microg/ml; C. innocuum, 0.25 microg/ml; C. perfringens, 0.125 microg/ml; C. ramosum, 1 microg/ml; Eubacterium spp., 1 microg/ml; Lactobacillus spp., >32 microg/ml, Propionibacterium spp., 0.5 microg/ml; and Peptostreptococcus spp., 0.25 microg/ml. Dalbavancin was 1 to 3 dilutions more active than vancomycin against most strains. Dalbavancin exhibited excellent activity against gram-positive strains tested and warrants clinical evaluation.

Bactericidal activities of methoxyfluoroquinolones gatifloxacin and moxifloxacin against aerobic and anaerobic respiratory pathogens in serum

Gatifloxacin (Bristol-Myers Squibb) and moxifloxacin (Bayer) are new methoxyfluoroquinolones with broad-spectrum activity against aerobic and anaerobic pathogens of the respiratory tract. In this investigation, we analyzed the bactericidal activity in serum over time of these antimicrobials against three aerobic (Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus) and four anaerobic (Peptostreptococcus micros, Peptostreptococcus magnus, Fusobacterium nucleatum, and Prevotella melaninogenica) bacteria associated with respiratory tract infections. Serum samples were obtained from 11 healthy male subjects following a single 400-mg oral dose of gatifloxacin and moxifloxacin. These samples were collected prior to and at 2, 6, 12, and 24 h after the dose of each drug. Gatifloxacin exhibited bactericidal activity for a median of 12 h against Streptococcus pneumoniae (MIC = 0.5 micro g/ml), Peptostreptococcus micros (MIC = 0.25 micro g/ml), and F. nucleatum (MIC = 0.5 micro g/ml) and 24 h against H. influenzae (MIC = 0.03 micro g/ml), Staphylococcus aureus (MIC = 0.125 micro g/ml), Peptostreptococcus magnus (MIC = 0.125 micro g/ml), and Prevotella melaninogenica (MIC = 0.5 micro g/ml). Moxifloxacin exhibited bactericidal activity for a median of 24 h against Streptococcus pneumoniae (MIC = 0.125 micro g/ml), H. influenzae (MIC = 0.015 micro g/ml), Staphylococcus aureus (MIC = 0.06 micro g/ml), F. nucleatum (MIC = 0.5 micro g/ml), Prevotella melaninogenica (MIC =0.5 micro g/ml), Peptostreptococcus magnus (MIC = 0.125 micro g/ml), and Peptostreptococcus micros (MIC = 0.25 micro g/ml). The results from this pharmacodynamic study suggest that these fluoroquinolones would have prolonged killing activity against these organisms in vivo and may have clinical utility in the treatment of mixed aerobic-anaerobic respiratory tract infections.

In vitro activities of daptomycin, vancomycin, quinupristin- dalfopristin, linezolid, and five other antimicrobials against 307 gram-positive anaerobic and 31 Corynebacterium clinical isolates

The activities of daptomycin, a cyclic lipopeptide, and eight other agents were determined against 338 strains of gram-positive anaerobic bacteria and corynebacteria by the NCCLS reference agar dilution method with supplemented brucella agar for the anaerobes and Mueller-Hinton agar for the corynebacteria. The daptomycin MICs determined on Ca(2+)-supplemented (50 mg/liter) brucella agar plates were one- to fourfold lower than those determined in unsupplemented media. Daptomycin was highly active (MICs, <or=2 microg/ml) against many strains including 36 of 37 peptostreptococci, 37 of 48 isolates of the Eubacterium group, and all strains of Propionibacterium spp., Clostridium perfringens, Clostridium difficile, and other Clostridium spp. It was fourfold or greater more active than vancomycin against Clostridium innocuum and 16 of 34 strains of vancomycin-resistant lactobacilli. Three strains of C. difficile for which quinupristin-dalfopristin and linezolid MICs were >8 microg/ml were inhibited by <1 microg of daptomycin per ml. Daptomycin MICs were >or=4 microg/ml for most strains of Clostridium clostridioforme, Clostridium paraputrificum, Clostridium tertium, and Clostridium ramosum; the isolates were generally more resistant to other antimicrobials. Daptomycin was two- to fourfold less active against Actinomyces spp. than vancomycin, quinupristin-dalfopristin, or linezolid. Twenty-nine of 31 strains of Corynebacterium spp., including Corynebacterium jeikeium, Corynebacterium amycolatum, and Corynebacterium pseudodiphtheriticum, were inhibited by <or=0.25 microg of daptomycin per ml. For two strains of "Corynebacterium aquaticum," 8 microg of daptomycin per ml was required for inhibition. Daptomycin demonstrated very good activities against a broad range of gram-positive organisms including vancomycin-resistant C. innocuum and lactobacillus strains and quinupristin-dalfopristin- and linezolid-resistant C. difficile strains.

In vitro activities of Garenoxacin (BMS 284756) against 108 clinical isolates of Gardnerella vaginalis

Garenoxacin (BMS 284756) was active against 105 of 108 (97%) recent clinical Gardnerella vaginalis isolates at < or =2 micro g/ml by using the reference agar dilution method for anaerobes. Twenty-eight percent of isolates (31 of 108) were resistant to metronidazole, and 44% were resistant to doxycycline. All were susceptible to clindamycin and ampicillin-sulbactam.

Comparative in vitro activities of ertapenem against bacterial pathogens from patients with acute pelvic infection

This study compared the in vitro activities of ertapenem, ceftriaxone, co-amoxiclav, ciprofloxacin and piperacillin-tazobactam against 314 aerobic bacteria and of ertapenem, piperacillin-tazobactam, cefoxitin, ceftriaxone, chloramphenicol, ticarcillin-clavulanate, ampicillin-sulbactam, clindamycin and metronidazole against 500 anaerobic bacteria from 212 patients with acute pelvic infection. Antimicrobial susceptibilities were determined by broth microdilution (aerobes) or agar dilution (anaerobes), following NCCLS guidelines. The most common isolates were Enterobacteriaceae and Peptostreptococcus spp. Ertapenem was the most active drug tested against Enterobacteriaceae (100% susceptible) and anaerobes (99.8% susceptible); the least active agents were co-amoxiclav (79% of Enterobacteriaceae susceptible) and ceftriaxone (85.9% of anaerobes susceptible). All agents tested had excellent activity against beta-haemolytic streptococci and methicillin-susceptible Staphylococcus aureus.

Sequence conservation and distribution of the fusobacterial immunosuppressive protein gene, fipA

Fusobacterium nucleatum is a gram-negative anaerobe involved in various diseases, including periodontitis. Recently, other investigators isolated the F. nucleatum FDC 364 fusobacterial immunosuppressive protein (FIP). One subunit, FipA, impairs T-cell activation in vitro and shows homology with beta-ketothiolases. However, its distribution and variability among fusobacteria was not reported. Cloned fipA gene sequences from F. nucleatum ssp. polymorphum (ATCC 10953) and F. nucleatum ssp. nucleatum (ATCC 23726) shared 89 and 92% identity, respectively, with FDC 364 fipA, and 90 and 94% identity, respectively, with the FDC 364 FipA predicted amino acid sequence. Southern blot analyses of chromosomal DNA from fusobacterial strains, including F. nucleatum and other Fusobacterium species, were performed using partial fipA sequences as probes. The results indicate that fipA is highly conserved among the F. nucleatum strains examined and that fipA homologues are widely distributed among fusobacteria. A clear relationship between immune suppression, metabolism and the FipA protein remains to be determined.

Comparative in vitro activity of faropenem and 11 other antimicrobial agents against 405 aerobic and anaerobic pathogens isolated from skin and soft tissue infections from animal and human bites

Faropenem, a new oral beta-lactam agent with a penem structure, was very active against 405 aerobic and anaerobic bite isolates. It inhibited 232 of 236 (98%) aerobic isolates, including all Pasteurella spp. and Eikenella corrodens at < or = 0.25 mg/L, and 164/169 (97%) anaerobic isolates, at < or = 1 mg/L. The 10 isolates that required > or = 2 mg/L for inhibition were one strain each of Acinetobacter lwoffi, Corynebacterium minutissimum, Bacteroides ovatus, Lactobacillus delbrueckii and Peptostreptococcus tetradius, plus Corynebacterium 'aquaticum' (two strains) and Veillonella sp. (three strains).

Multilaboratory comparison of anaerobe susceptibility results using 3 different agar media

A 5-laboratory study was performed that used the National Committee for Clinical Laboratory Standards (NCCLS) reference agar dilution method with 3 media formulations to determine whether the use of different media would affect minimum inhibitory concentration (MIC) results. Wilkins-Chalgren, Brucella-based blood agar (BRU), and Wilkins-Chalgren agar plus blood (WCB) and 6 antibiotics (clindamycin, cefoxitin, ceftizoxime, piperacillin, metronidazole, and trovafloxacin) were evaluated with 58 isolates. The MIC values were compared, and a significant correlation of >0.80 was demonstrated for all media and each antibiotic/organism group. The cumulative rate of errors for all antibiotics was 0.1%. These data indicate that a change in the NCCLS reference medium for testing of anaerobic bacteria susceptibility to either BRU or WCB will not affect the MIC results for the antibiotics and organisms evaluated.

Multilaboratory comparison of growth characteristics for anaerobes, using 5 different agar media

A multilaboratory study compared the growth of 30 fastidious anaerobes, using 5 different agar media: Wilkins-Chalgren (WC), WC with either whole or laked sheep blood, and Brucella supplemented with vitamin K(1) and hemin and either laked or whole sheep blood. The media were compared for quality and quantity of growth. Experiments were conducted either entirely in an anaerobic chamber or inoculated in ambient air with anaerobic incubation. The results showed that (1) any medium plus whole or laked blood was better than unsupplemented WC, (2) whole blood and laked blood additives gave similar results, (3) supplemented Brucella with whole or laked blood was superior to WC and WC with whole or laked blood, and (4) anaerobic and aerobic inoculation with anaerobic incubation gave similar results. Brucella agar supplemented with whole or laked blood supports the growth of fastidious anaerobic species better than the WC agars do.

Update on the taxonomy and clinical aspects of the genus fusobacterium

The genus Fusobacterium currently includes 13 species. Fusobacterium nucleatum, the most frequently encountered species in humans, is heterogeneous and currently includes 5 subspecies. A potentially new subspecies of F. nucleatum that is intrinsically quinolone-resistant and phylogenetically separate from the other 5 subspecies has been identified from dog and cat oral flora. Two subspecies have been described for Fusobacterium necrophorum, and a new species, Fusobacterium equinum, which is related to F. necrophorum, has been described from horse oral flora. Additional molecular studies have characterized Fusobacterium ulcerans as separate from the phenotypically similar Fusobacterium mortiferum and Fusobacterium varium. Fusobacterium sulci and Fusobacterium alocis have been reclassified as Eubacterium sulci and Filifactor alocis, respectively. Fusobacterium prausnitzii is phylogenetically related to the Eubacterium-like organisms and will likely be reclassified in the future. The status of the remaining species is unchanged.

General microbiology and in vitro susceptibility of anaerobes isolated from complicated skin and skin-structure infections in patients enrolled in a comparative trial of ertapenem versus piperacillin-tazobactam

In a recently completed study of once-a-day ertapenem versus piperacillin-tazobactam every 6 h in the treatment of complicated skin and skin-structure infections, 540 patients were randomized in a 1rcolon;1 ratio and assigned to 1 of 2 strata: those with a complicating underlying disease or all others. The most common infections in the study were deep soft-tissue abscess (18.9%), followed by diabetic lower extremity infection (18.1%); 7.0% of these were perineal cellulitis/abscess. With the exception of methicillin-resistant Staphylococcus aureus, almost all of the predominant aerobic pathogens were susceptible to both study drugs. Eighty-seven patients (16%) had >/=1 anaerobe identified in their baseline wound cultures, with a total of 232 anaerobic isolates. Of the 141 anaerobes tested for susceptibility, 97.2% were susceptible to ertapenem and 97.9% to piperacillin-tazobactam. Ertapenem had excellent in vitro activity against the most common aerobic pathogens and almost all anaerobes recovered from patients with infections of the skin and skin structures.

In vitro activities of garenoxacin (BMS-284756) against 170 clinical isolates of nine Pasteurella species

The in vitro susceptibilities of 170 clinical isolates plus 12 American Type Culture Collection strains of Pasteurella species comprising nine species and three Pasteurella multocida subspecies were studied by an agar dilution method. Garenoxacin (BMS-284756), a new des-fluoro(6) quinolone, was active at 90% of the strains susceptible to Collapse

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MESH Headings

• Anti-Infective Agents/pharmacology
• Bites and Stings/microbiology
• Culture Media
• Drug Resistance, Bacterial
• Fluoroquinolones
• Humans
• Indoles
• Microbial Sensitivity Tests
• Pasteurella/drug effects
• Pasteurella Infections/microbiology
• Quinolones
• United States

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Two novel vaginal microbicides (polystyrene sulfonate and cellulose sulfate) inhibit Gardnerella vaginalis and anaerobes commonly associated with bacterial vaginosis

This is the first report demonstrating the in vitro inhibitory activity of two novel microbicides (cellulose sulfate and polystyrene sulfonate) against bacterial vaginosis (BV)-associated bacteria. Vaginal application of these microbicides not only may reduce the risk of acquisition of human immunodeficiency virus and other sexually transmitted infection-causing organisms but may also decrease the incidence of BV.