Mice were treated with voriconazole at 5, 10 and 20 mg/kg once a day and 20 mg/kg twice a day or with fluconazole at 20 mg/kg once or twice a day orally. Intravaginal treatments were evaluated with voriconazole and fluconazole at 0.5, 1 and 5 mg/kg once a day. All treatment regimens were given on days 1–5 post-challenge. One day 6, the vaginas were swabbed to assess treatment effects.

Mice treated orally with voriconazole at ≥10 mg/kg and fluconazole at ≥20 mg/kg showed significantly reduced fungal counts over controls (P = 0.0002–0.007). Significant differences were found between the groups that received voriconazole at 20 mg/kg once or twice daily and those that received fluconazole at 20 mg/kg once or twice daily, orally (P = 0.010 and 0.001, respectively). Mice treated with voriconazole or fluconazole administered intravaginally at ≥0.5 mg/kg exhibited a reduced fungal burden when compared with the control group (P = 0.0002–0.007). There was no statistically significant difference in fungal burden between topical treatment with doses of 0.5, 1 and 5 mg/kg once daily of voriconazole or fluconazole. Sterilization of vaginas was not observed with voriconazole and fluconazole without taking into consideration the therapeutic modality.

Voriconazole could emerge as a new alternative for treatment of vaginal candidosis.

Nucleic acid sequences from gyrA, gyrB, parC and parE genes from all 14 Ureaplasma serovars were aligned. Full genome sequences for serovars 1, 3–7, 9 and 11–14 were available from the National Center for Biotechnology Information database and we sequenced the full topoisomerase genes from ciprofloxacin-susceptible reference strains of serovars 2, 8 and 10. Phylogenetic trees were constructed to analyse nucleotide sequence similarity. Deduced amino acid sequences were compared with all 33 previously reported fluoroquinolone-resistant strains to clarify true fluoroquinolone-resistance-associated substitutions.

Non-resistance-associated polymorphisms were identified in GyrA (39), GyrB (26), ParC (107) and ParE (34) proteins. Phylogenetic analysis demonstrated species clustering for all genes, except parE in which serovars 4, 12, 10 and 13 formed a separate cluster more similar to Ureaplasma parvum than the remaining Ureaplasma urealyticum serovars. Examination of all previously reported fluoroquinolone-resistant strains found that one-third of identified residue substitutions could be attributed to normal species polymorphism; therefore, the mechanism of resistance for these strains is still undetermined. In particular, Glu or Asp at position 112 in GyrA and Ala or Thr at 125/136 in ParC were substitutions identified when U. urealyticum strain sequences were previously aligned with the published serovar 3 genome sequence.

Combining analysis of the recently available Ureaplasma genomes with sequences from the additional serovars has enabled us to clarify which substitutions found by previous investigators could potentially be responsible for fluoroquinolone resistance.

Using an in vitro study to assess inhibition of the growth of P. aeruginosa, MIC₉₀ and MIC₅₀ values of amikacin, gentamicin, netilmicin, tobramycin and isepamicin were determined, either alone or in combination with fosfomycin, and then the fractional inhibitory concentration index was calculated. In the biofilm-infected rat model, the efficacy and effects of treatment with isepamicin and fosfomycin on infection were studied.

The combinations of amikacin and fosfomycin or isepamicin and fosfomycin showed the most significant synergistic effects against P. aeruginosa as compared with other treatments. In the biofilm-infected rat model, as a single agent, neither isepamicin nor fosfomycin reduced C-reactive protein level and numbers of white blood cells, or reduced the colony counts of the bacteria from both tissue and silica gel tubes. However, the combination of these two agents resulted in a good therapeutic effect.

Combination of aminoglycosides and fosfomycin not only showed a positive effect in vitro but also improved the therapeutic effect in a biofilm-infected rat model. This offers an effective treatment strategy against some therapy-resistant infections.

We determined the MICs of lacticin 3147 and nisin for 20 strains of methicillin-resistant Staphylococcus aureus (MRSA), 20 strains of vancomycin-resistant enterococci (VRE), 6 strains of S. aureus with intermediate resistance to vancomycin (VISA), 5 strains of heterogeneous vancomycin-intermediate S. aureus (hVISA) and 4 strains of S. aureus that are susceptible to methicillin.

Lacticin 3147 displayed potent activity against VRE with MIC values between 1.9 and 7.7 mg/L, and varying levels of activity against S. aureus strains (MRSA, 1.9–15.4 mg/L; laboratory strains, ≥15.4 mg/L; hVISA, 15.4–30.9 mg/L; VISA, ≥61.8 mg/L). Nisin was more active against the S. aureus strains in general (MRSA and laboratory strains, 0.5–4.1 mg/L; VISA and hVISA, 2 to ≥8.3 mg/L), but was less effective than lacticin 3147 against VRE (2 to ≥8.3 mg/L).

Nisin is more effective against S. aureus whereas lacticin 3147 possesses greater potency against VRE. The modifications responsible for the vancomycin-resistant phenotypes of hVISA and VISA strains also provide protection against the two lantibiotics.

Between January 2004 and May 2006, retrospective histories of hospital admissions, antimicrobial treatment and co-morbidities were collected. Faecal samples were cultured for MDR E. coli. These isolates and their ESBL genes were typed by a reference laboratory.

Of the 294 patients included in the study, faecal samples from 119 (40.5%) grew MDR E. coli. The proportion of carriers in the different homes ranged from 0% to 75%. Epidemic strain A belonging to the ST131, O25:H4 lineage with the CTX-M-15 enzyme accounted for 58 (49%) of all isolates; its proportion varied from 0% to 100% among homes. Fifty-one percent of carriers had no history of recent hospital admission and only 13.5% had a known history of ESBL E. coli colonization or infection. In a multivariate logistic regression model, days of fluoroquinolone use [odds ratio (OR) = 1.33, 95% confidence interval (CI) 1.04–1.69, P = 0.02] and a history of urinary tract infection (OR = 2.56, 95% CI 1.37–4.78, P = 0.003) were the only variables independently associated with the risk of carrying MDR E. coli.

The high level of faecal carriage of MDR E. coli in nursing home residents demonstrates their importance as a reservoir population. Public health measures to combat spread of these organisms should address the needs of this group.

We conducted a nationwide cohort study of all Danish singleton children born between 1995 and 2003 (n = 611 410) with individual-level information on antibiotic prescriptions, intussusception and potential confounding variables. Using Poisson regression, we estimated rate ratios of intussusception according to antibiotic use, including estimating increases in rate ratios per dose of antibiotics and rate ratios for time periods following antibiotic use.

Intussusception was diagnosed in 434 children during 1 180 749 person-years of follow-up. The intussusception rate ratio was 1.51 [95% confidence interval (CI), 1.19–1.91] comparing antibiotic users with non-users. In the first week following use of extended-spectrum penicillins the rate ratio was 4.68 (95% CI, 2.93–7.47). In the first week following use of macrolides the rate ratio was 3.82 (95% CI, 1.22–11.90). The proportion of all cases attributable to extended-spectrum penicillins and macrolides was 4%.

This is the first prospective study to show an association between antibiotics and intussusception. The association was strong, temporal and biologically plausible. The magnitude of the observed effect and a number of sensitivity analyses favour a causal relationship. However, the potential for confounding-by-indication cannot be completely discounted and controlled studies of the observed association will be necessary for more definite confirmation.

Storage life and time dependency, susceptibilities of opportunistic bacterial and fungal pathogens, and synergistic and adverse effects of combinations with other anti-Acanthamoeba substances were determined. Moreover, an organotypic skin equivalent was adapted for investigating the penetration of acanthamoebae into the epidermis and the human tissue tolerability of miltefosine.

It was shown that miltefosine can be stored as a 2 mM stock solution and also as a 50 µM dilution over a period of 12 months at 4°C without any loss of activity. Efficacies against staphylococci and Candida albicans were established. Acanthamoebae were able to penetrate the skin equivalent within 24 h. This penetration was prevented by treatment with miltefosine, while miltefosine treatment was well tolerated by the skin equivalent.

Miltefosine has been approved for oral and topical treatment of leishmaniasis and may also be a promising candidate for the topical treatment of Acanthamoeba infections.

All inpatients were eligible for OHPAT, provided that they had a serious infection requiring parenteral therapy, were well enough to leave hospital and fulfilled other criteria. We initially used an outpatient clinic model, but as the service developed, treatment was often delivered in patients' homes, with the OHPAT team providing training and assessment of primary care staff.

Four hundred and sixty-seven patients were referred to the service between September 2004 and April 2008. Of these, 273 received 303 courses of OHPAT, 48 were discharged on oral therapy and 3 patients declined outpatient therapy; the remaining 143 patients were deemed unsuitable for inclusion, most commonly because the patient was too unwell for discharge (28.7%) or their social situation was inappropriate (14.7%). Causative organisms were identified in two-thirds of cases, with methicillin-resistant Staphylococcus aureus implicated in one-third of these. Mean treatment length was 24 days (range 1–165 days), with 7394 inpatient bed-days saved. Less than 5% of patients were readmitted within 28 days with infection- or drug-related problems. There were no cases of Clostridium difficile-associated diarrhoea during or after outpatient treatment, despite extensive use of cephalosporins and other broad-spectrum agents. Patients found the service highly satisfactory and felt that it had improved their quality of life during the treatment period.

The introduction of the OHPAT service at St Mary's Hospital has proved to be of benefit to patients and hospital efficiency alike.

Antibiotic susceptibility was studied by microdilution. All penicillin-resistant pneumococci were typed by PFGE and selected strains were studied by multilocus sequence typing (MLST). The presence of genes related to the Tn916 family of transposons was investigated by PCR.

From a total of 1197 invasive pneumococcal isolates of serotype 19A received at the Spanish Reference Laboratory between 1997 and 2007, 51 (4.3%) strains showed high-level resistance to penicillin (MICs of 2–4 mg/L). These 51 isolates belonged to three multiresistant clones related to sequence type (ST)81 (n = 21), ST320 (n = 19) and ST276 (n = 11). All 51 serotype 19A pneumococci were tetracycline-resistant and had the tet(M) gene, and 41 strains were macrolide-resistant, harbouring the erm(B) gene. The presence of int and xis genes was detected in all strains associated with other genes of the Tn916 family.

The rise in penicillin-resistant serotype 19A invasive pneumococci in Spain was associated with the emergence and clonal spread of two worldwide-disseminated multiresistant clones (ST276 and ST320). The Spain^23F-1-19A (ST81) clone remained stable throughout the study period. Multidrug resistance was associated with transposons of the Tn916 family.

In total, 205 tetracycline-resistant isolates were screened for tet(M) by PCR. tet(M) genes were sequenced and compared with tet(M) deposited in GenBank. Based on phylogenetic analysis isolates were screened for Tn916- and Tn5801-like xis/int genes, and transposons were confirmed by linking PCR. spa typing was performed and selected isolates were used as donors in a filter mating experiment.

Forty-one isolates (21.3%, 60.7%, 2.6% and 4.4% of the human, pig, poultry and cattle isolates, respectively) were tet(M) positive. tet(M) was located on Tn5801-like and Tn916-like transposons in humans and on a specific Tn916-like element in animals. Human isolates were of different spa types (t034, t008, t037, t051, t065, t078, t318 and t964) corresponding to different clonal complexes (CC398, CC8, CC25 and CC30). Animal isolates were of spa type t034, t011 or t0571 corresponding to CC398. tet(M) sequence types correlated with CC types. Tn916-like and Tn5801-like (Tn6014) transposons were able to transfer to S. aureus recipients.

S. aureus of human origin contained diverse tet(M) located on Tn916- and Tn5801-like (Tn6014) transposons, and S. aureus of animal origin contained Tn916-like tet(M) genes. This suggests that conjugative transposition plays an important role in the evolution and horizontal spread of tet(M) in S. aureus. This is the first study showing horizontal transfer of Tn5801 (Tn6014).

A total of 162 K. pneumoniae isolates from five hospitals located in three geographical areas of Spain were characterized. The number of isolates from each hospital ranged from 3 to 82. The genetic relationship between isolates was established by PFGE and multilocus sequence typing (MLST). bla_ESBL types and other antibiotic resistance genes were analysed by PCR and sequencing. Plasmids were classified according to their incompatibility group by a PCR-based replicon-typing scheme.

All 162 isolates carried the bla_CTX-15 gene. Fifty-eight isolates (35.8%) caused clinical infections and 104 (64.2%) were colonizers. Sixty-nine (42.6%) isolates were collected from newborns and 93 (57.4%) from adults. Using PGFE, the 162 isolates were grouped into seven clusters that were further identified as members of the MLST types 1, 11, 14, 17, 20, 35 and 36. Two hospitals each had two different clones and the remaining three hospitals had a single CTX-M-15-producing K. pneumoniae clone. All clones carried different antibiotic resistance genes, including bla_OXA-1, aac(3)-IIa, aac(6')-Ib-cr, qnrS1 and qnrB. In four of the seven (57.1%) clones the bla_CTX-M-15 gene was transferred by conjugation; in all cases plasmids of the incompatibility group IncF were identified by PCR.

This study shows that multiresistant K. pneumoniae producing CTX-M-15 of MLST types 1, 11, 14, 17, 20, 35 and 36 are spreading as pathogens and colonizers among newborns and adult patients in Spain.

During a 12 month period (October 2007–September 2008), 47 patients in Hippokration University Hospital yielded K. pneumoniae isolates that exhibited reduced susceptibility to carbapenems and were phenotypically positive for carbapenemase production but negative for metallo-β-lactamase (MBL) production. Single patient isolates were tested by Vitek 2, Etest, agar dilution MICs, phenotypic assays and PFGE. Carbapenemase and other β-lactamase genes were identified by PCR and sequencing. Patient records were retrospectively reviewed to access co-morbidities, antibiotic exposure prior to infection and outcome.

The 47 K. pneumoniae isolates exhibited various susceptibilities to imipenem and meropenem; all were non-susceptible to ertapenem and several other antibiotics but most were susceptible to gentamicin, colistin and tigecycline. PFGE classified the isolates into two clonal types, with the predominant type, which was closely related to that of hyperepidemic strains from the USA and Israel, comprising three subtypes. All isolates carried the bla_KPC-2 gene; 45 also carried bla_SHV-12 and 29 bla_TEM-1. Patients were hospitalized in nine different units. The median length of hospital stay prior to KPC isolation was 21 days; 38 patients (80.9%) had evidence of clinical infection due to a KPC producer and 16 (34%) had bacteraemia. The crude mortality rate was 27.7%. A β-lactam/β-lactamase inhibitor combination was the most frequently administered antimicrobial prior to KPC isolation (20 patients; 42.5%), whereas only nine patients (19.1%) had prior carbapenem use.

This study presents for the first time a wide intrahospital spread of KPC-producing K. pneumoniae clones in a European hospital. The KPC producers were rapidly disseminated in several units, indicating the difficulty in restraining such multidrug-resistant clones when they have been established in a hospital environment.

The genes affected by the transposon insertion were identified by plasmid rescue and sequencing. Expression levels of the relevant genes were determined by semi-quantitative RNA hybridization and catabolic activity by lactate dehydrogenase/pyruvate oxidoreductase assays.

A metronidazole-resistant mutant was isolated and the transposon insertion site was identified in an intergenic region between the rhaO and rhaR genes of the gene cluster involved in the uptake and catabolism of rhamnose. Metronidazole resistance was observed during growth in defined medium containing either rhamnose or glucose. The metronidazole-resistant mutant showed improved growth in the presence of rhamnose as compared with the wild-type parent. There was increased transcription of all genes of the rhamnose gene cluster in the presence of rhamnose and glucose, likely due to the transposon providing an additional promoter for the rhaR gene, encoding the positive transcriptional regulator of the rhamnose operon. The B. thetaiotaomicron metronidazole resistance phenotype was recreated by overexpressing the rhaR gene in the B. thetaiotaomicron wild-type parent. Both the metronidazole-resistant transposon mutant and RhaR overexpression strains displayed a phenotype of higher lactate dehydrogenase and lower pyruvate oxidoreductase activity in comparison with the parent strain during growth in rhamnose.

These data indicate that overexpression of the rhaR gene generates metronidazole resistance in B. thetaiotaomicron

The GFP gene was integrated downstream of the 18S ribosomal promoter region of Leishmania donovani. After initial selection, GFP-expressing parasites—both sodium stibogluconate (SAG)-susceptible (2001) and -resistant (2039) isolates—were grown without adding G418. The infectivity of these transfectants to macrophages (J774.1) as well as to hamsters was checked. The ex vivo screening assay was standardized using standard antileishmanial drugs.

A constitutive and enhanced expression of GFP in promastigote and amastigote stages was achieved for ~12 months without any need for drug pressure. These transfectants were highly infective to macrophage cell lines as well as to hamsters, as observed by fluorescence microscopy and flow cytometry (FACS). GFP-tagged promastigotes as well as intracellular amastigotes were found to be highly susceptible to miltefosine, amphotericin B and pentamidine, in a concentration-dependent manner. SAG was inactive against the GFP-promastigotes, as well as SAG-resistant intracellular amastigotes, correlating well with earlier reports.

The GFP-transfectants were found to be suitable for FACS-based ex vivo screening assays. They were also infective to hamsters up to day 60 post-infection.

Laboratory data on pneumococcal isolates collected from Chang Gung Memorial Hospital during 2000–07 were analysed using the original and modified penicillin CLSI breakpoints.

A total of 3729 non-duplicate isolates were identifed, including 43 (1.2%) meningeal isolates showing high rates of penicillin (79.1%) and ceftriaxone (34.9%) resistance. For non-meningeal isolates, penicillin non-susceptibility was reduced significantly from 75.1% (72.4% in 2000–03 increasing to 77.4% in 2004–07) to 16% (28.6% in 2000 decreasing to 2.4% in 2007) if the modified breakpoints were applied. However, isolates for which penicillin MICs were 1–2 mg/L increased significantly from 34.2% in 2000 to 59.8% in 2007. Ceftriaxone non-susceptibility also increased significantly from 2.8% before 2005 to 18.4% thereafter. A quarter (25.7%) of the pneumococcal isolates were recovered from patients <10 years old. Higher resistance to penicillin (89.8% versus 70.4%; or 19.1% versus 13.2% by the modified breakpoints) or ceftriaxone (11.1% versus 5.8%) was found among these isolates, compared with those from older patients.

With the implementation of the new breakpoints, clinicians may continue to use penicillin for the treatment of non-meningeal pneumococcal infections in preference to other drug classes. However, as isolates with borderline penicillin MICs are increasing, continued surveillance of pneumococcal susceptibility to penicillin will be needed.

A collection of 126 rifampicin-resistant Mycobacterium tuberculosis and Mycobacterium africanum isolates and 18 rifampicin-susceptible isolates from different countries were analysed using the two hybridization assays.

For 60 strains the hot-spot region of the rpoB gene was sequenced, confirming the results of the hybridization assays and allowing the identification of new mutations. In total, 17 mutations involving 10 codons were observed, two of which are newly described (D516Y and E562G/P564L). Mutations L533P, H526L, D516Y and L511P and the double mutation E562G/P564L conferred a low level of resistance.

The assays INNO-LiPA Rif.TB and MTBDRplus identified rpoB mutations in 98.4% of cases. MTBDRplus provided additional information due to the overlapping hybridization probes and in addition allowed the investigation of katG mutations for isoniazid resistance.

A total of 751 tuberculosis isolates were tested for drug resistance using phenotypic antimicrobial susceptibility testing methods. Isolates were then characterized using molecular methods. Following DNA extraction, PCR amplification and sequence analysis were performed on the rifampicin resistance region of rpoB, as well as the region surrounding katG315 and the inhA promoter region associated with isoniazid resistance.

Eighteen different mutation types were found in the rpoB region of rifampicin-resistant isolates. Isolates with mutations at residues rpoB531 (64.1%), rpoB526 (15.2%) and rpoB516 (8.7%) were the most common. In addition, an insertion was found at residue 514. Three phenotypically rifampicin-resistant isolates (3.3%) were genotypically wild-type. In isoniazid-resistant strains, mutations were found most commonly at katG315 (45.4%) as well as at the inhA promoter region (28.6%). Thirty-nine isolates (25.3%) were phenotypically isoniazid-resistant but genotypically wild-type. The katG315 mutation was statistically associated with multidrug-resistant isolates.

This study expands the knowledge of mutations that potentially contribute to drug resistance in tuberculosis and lays the foundation for developing molecular-based tests to determine drug resistance in clinical tuberculosis isolates.

Adult patients with prior failure to two or more PI-based regimens and on a failing PI regimen were randomized to STD-FPV/RTV (n = 24), HD-FPV/RTV (n = 25) or FPV/LPV/RTV (n = 25). The primary aim was to test week 24 superiority of HD-FPV/RTV and FPV/LPV/RTV over STD-FPV/RTV as measured by plasma HIV-1 RNA average area under the curve minus baseline (AAUCMB).

There was no difference in the week 24 AAUCMB between the regimens. The proportion of patients with <50 copies/mL of plasma HIV RNA was 21%, 24% and 20%, respectively, by time to loss of virological response (TLOVR) analysis. High baseline drug resistance provided some explanation for the low efficacy. A lower baseline background drug resistance and higher fosamprenavir genotypic inhibitory quotient led to better antiviral responses. The plasma amprenavir trough concentartion (C) was 49% higher in the HD-FPV/RTV arm than in the STD-FPV/RTV arm and similar in the FPV/LPV/RTV and STD-FPV/RTV arms. The plasma lopinavir C was similar to historical data with standard LPV/RTV 400 mg/100 mg twice daily. All regimens were relatively well tolerated, although diarrhoea was more frequent in the HD-FPV/RTV and FPV/LPV/RTV arms, and hypertriglyceridaemia and increased total cholesterol were more common in the FPV/LPV/RTV arm.

While the strategies of higher dose FPV/RTV and dual FPV/LPV/RTV were relevant at the time of study initiation, new therapies for antiretroviral-experienced patients make such strategies of limited interest. In addition, this study failed to demonstrate antiviral superiority of the HD-FPV/RTV or FPV/LPV/RTV regimen over the STD-FPV/RTV twice-daily regimen in highly treatment-experienced patients.

RT nucleotide sequences of 1893 HIV-1 isolates from 1680 persons with different treatment histories (including naive and treated patients) were analysed. ² contingency tests were performed to detect mutations within positions 1–333 of HIV-1 RT, associated with therapy failure, and correlated mutations were identified using statistical methods.

Thymidine analogue resistance mutations were strongly associated with therapy failure to all nucleoside analogue combinations analysed. Previously identified accessory mutations at positions 35, 39, 43, 90, 98, 101, 122, 178, 196, 203, 208, 221, 223 and 228 were associated with therapy failure with at least one of the drug combinations studied. Interestingly, several mutations affecting RT thumb subdomain polymorphisms were strongly associated (P < 10^–3) with therapy failure to abacavir/stavudine, stavudine/didanosine and abacavir/stavudine/didanosine. Mutations A272P, K277R and V293I were more prevalent in patients failing treatment with abacavir/stavudine than in naive individuals, while mutation frequencies of T286A, V292I and to a lesser extent E291D and E297K decreased in the treated population. These effects were also detected for A272P, T286A and V292I, when analysing didanosine/stavudine therapy failure, although statistical significance was higher for T286A.

RT thumb subdomain polymorphisms are strongly associated with therapy failure to nucleoside analogues. Based on their structural location, we suggest a role for those residues in controlling the balance between RNase H degradation and nucleotide excision during DNA polymerization.

Albendazole–PEG 6000 (1:1, 1:5 and 1:9 ratios) solid dispersions were prepared by the solvent evaporation method. The morphology of the particles was evaluated by scanning electron microsocopy (SEM), and in vitro dissolution assays were also carried out. Mice were infected with T. canis and then treated orally with albendazole–PEG 6000 systems or albendazole suspended in water. The anthelmintic effect was examined at 28 days post-infection (p.i.). The number of larvae recovered from mice treated with albendazole alone and those treated with albendazole–PEG 6000 were compared with the numbers from the placebo group.

Dissolution of albendazole from solid dispersions was markedly enhanced by increasing the polymer concentration. At a 1:9 drug:polymer ratio, >90% of the albendazole was dissolved in 10 min. SEM showed microparticles to be of small spherical shape compared with the pure components. In vivo evaluation of larva migration showed that both albendazole–PEG 6000 solutions exhibited a greater anthelmintic effect in the brain (0 larvae/mouse). In addition it was also found that liver and lung showed a significant decrease in the number of larvae. Evaluation of vehicle toxicity (PEG 6000 in water) showed a mice survival rate of 100% at the assayed concentrations.

These data suggest that albendazole–PEG 6000 solid dispersions markedly increased the effectiveness of albendazole against the migratory activity of larvae. Particularly, these polymeric solutions were able to totally prevent migration of larvae to the mouse brain.

We examined the effect of extended-spectrum β-lactamases (ESBLs) and AmpC β-lactamases on the activity of razupenem, using the CLSI agar dilution method to measure MICs for mutants, transconjugants and isolates with and without these enzymes.

ESBLs had no effect on the activity of razupenem against Escherichia coli and Klebsiella spp., and only a small effect when coupled with outer membrane impermeability. Inducible or, more especially, derepressed AmpC enzymes gave some protection, with most AmpC-derepressed Enterobacter and Citrobacter spp. requiring MICs of ~8 mg/L. This relative resistance was further increased when porins were lost, restricting drug uptake. Metallo- and class A-carbapenemases conferred resistance, with MICs ≥16 mg/L.

Razupenem has good activity against ESBL producers, but is affected by AmpC enzymes, especially when derepressed and coupled with outer membrane impermeability; its activity is also compromised by carbapenemases.

Enzymatic activity of purified recombinant KPC-2 was measured with nitrocefin as reporter substrate and inhibition by NXL104 was measured by determination of IC₅₀ values. Antimicrobial susceptibility testing of various β-lactams combined with a fixed concentration of NXL104 at 4 mg/L against strains producing KPC enzymes was performed by the broth microdilution method.

NXL104 was a potent inhibitor of KPC-2 with an IC₅₀ of 38 nM. NXL104 restored the antimicrobial activity of ceftazidime, ceftriaxone, imipenem and piperacillin against Enterobacteriaceae strains producing KPC-2 or KPC-3. MIC values of ceftazidime against KPC producers were reduced by up to 1000-fold by combination with NXL104.

NXL104 inhibitory activity is unique in terms of spectrum, encompassing class A extended-spectrum β-lactamases, class C enzymes and class A carbapenemases. Given the limited therapeutic options available for infections caused by multiresistant Enterobacteriaceae isolates, NXL104 β-lactamase inhibitor is a promising agent to be used in combination with a β-lactam to protect its antibacterial activity.

The study included 84 children and adolescents (median age: 11 years) who received 141 consecutive courses of LAMB for prophylaxis (32), empirical therapy (83), possible (19) or probable/proven (7) invasive infections. LAMB was administered until intolerance or maximum efficacy at dosages individually determined by the responsible physician.

Fifty-nine courses were post-HSCT (42%, 49 allogeneic), and 92 courses were started during granulocytopenia (65%). The median duration of LAMB therapy was 13 days (range 1–79), and the median maximum dosage was 2.8 mg/kg (range 0.93–5.10). Mild-to-moderate adverse events were noted during 109 courses (77%; hepatic, 58.8%; electrolyte wasting, 52.5%; renal, 31.9%; infusion-related reactions, 8.5%); adverse events necessitating discontinuation of LAMB occurred in 6 courses (4.3%; renal, 3; anaphylaxis, 2; hepatic, 1). While median hepatic transaminase, alkaline phosphatase and blood urea nitrogen values were slightly (P < 0.01) higher at end of treatment (EOT), bilirubin and creatinine values were not different from baseline. Complete or partial responses were observed in 16/19 and 2/7 courses for possible and probable/proven invasive infections. Thirty-two of 33 courses of prophylaxis and 74 of 83 courses of empirical therapy were completed with success. Overall survival was 90.8% at 3 months post-EOT.

LAMB had acceptable safety and tolerance and was useful in prevention and treatment in unselected, mostly granulocytopenic paediatric patients undergoing treatment for cancer or HSCT.

We searched the PubMed, Cochrane library and EMBASE electronic databases up to December 2008. We included all published randomized controlled trials assessing HAART for treatment-naive adult HIV-infected individuals, with 48 weeks' follow-up. The quality of AE reporting was extracted according to CONSORT guidelines. We pooled the relative risks for AEs and compared results by sponsorship and different reporting methods.

Forty-nine trials, including 19 882 patients, published between 2000 and 2008, met the inclusion criteria. Only one of the trials reported on AE collection methods. Twenty-six trials reported only AEs attributed to drugs, 17 of which did not refer to the attribution methods. AE reporting was nearly always selective and selection criteria were highly variable, based on severity grading or occurrence threshold. Presentation of AEs above an occurrence threshold was more common in studies sponsored by industry (30/31) than in studies sponsored by non-profit organizations (3/18). Moreover, we showed that differences in the methods of reporting AEs may affect the results reported for AEs. No significant improvement in AE reporting was seen over this period.

We found substantial variability in AE reporting. Variability was influenced by sponsor identity and affected outcomes. These facts obstruct our ability to choose HAART based on currently published data.

Randomized clinical trial focusing on patient-reported information regarding their compliance and adverse events.

Of the randomized patients, 99% reported information regarding their compliance and adverse events. A 100% tablet intake was reported by 90% of the clarithromycin group and by 93.7% of the placebo group. Of the clarithromycin patients, 39.5% reported at least one non-serious adverse event versus 25.1% of the placebo patients (P < 0.001). Gastrointestinal adverse reactions were reported 950 times by 697 patients (32.3%) in the clarithromycin group and 485 times by 390 patients (17.9%) in the placebo group (P < 0.001). No significant differences were seen in other non-serious or serious adverse events during the first month after inclusion. Short-term non-serious adverse events did not explain the previously reported long-term significantly increased mortality associated with clarithromycin.

Gastrointestinal adverse reactions are common during clarithromycin administration, but at least half are also seen with a placebo.

We reviewed 99 patients with PHI who were managed with SEA using an ALCS from February 2002 to October 2005. A standard (4–6 week) antibiotic treatment course was administered in the first 46 patients and a short-term (1 week) therapy was adopted in the subsequent 53 patients.

Eight patients (four in each group) had persistent infection following the first attempt of surgery and antibiotic treatment; in three of them the infection was cured by additional debridement prior to re-implantation. Forty-two (91%) patients in the long-term group and 47 (89%) patients in the short-term group were free of infection (P = 0.67) at an average follow-up of 43 months (range, 24–60 months). Five (11%) patients developed complications related to prolonged antibiotic therapy. The short-term treatment resulted in a shorter hospital stay (18 versus 43 days, P < 0.001) and a lower direct medical cost (US$13 732 versus US$21 756, P < 0.001).

Short-term antibiotic therapy was not associated with a higher rate of treatment failure. Given the higher costs and incidence of complications, protracted courses of antibiotic administration may not necessarily be routine practice in patients with PHI undergoing SEA, provided that an ALCS is used.

Non-duplicate German isolates from the National Salmonella Reference Laboratory Collection (2003–07) with ceftiofur MICs of ≥4 mg/L were tested for β-lactam/β-lactamase inhibitor susceptibility, presence of ESBLs or AmpC-encoding genes, class 1 and 2 integrons, other resistance genes, and IS26 and ISEcp1 sequences by PCR/sequencing. The isoelectric point of the β-lactamase was determined. Strains were analysed by PFGE and plasmid profiling. The bla genes were mapped by Southern-blot hybridization. Plasmids were characterized by rep-PCR typing.

Sixteen isolates (10 Salmonella Typhimurium, 2 Salmonella Anatum, 2 Salmonella Paratyphi B dT + , 1 Salmonella Infantis and 1 Salmonella London) carried bla_CTX-M (15 bla_CTX-M-1 and one bla_CTX-M-15) genes located on self-transferable IncB/O, IncI1 and/or IncN plasmids. Seven of the Salmonella Typhimurium isolates carried the SGI1-M variant. Six isolates (five Salmonella Agona and one Salmonella Kentucky) carried the bla_CMY-2 gene on IncI1 conjugative plasmids. bla_TEM-20 genes were detected in two Salmonella Paratyphi B dT+ isolates, and bla_TEM-52 in one Salmonella Paratyphi B dT+ and one Salmonella Virchow, located on IncI1 plasmids. All Salmonella Paratyphi isolates harboured a 2300 bp/dfrA1-sat2-aadA1 class 2 integron.

Among the 22 679 German Salmonella isolates investigated, the ESBL and AmpC β-lactamase prevalence was still low; however, it is slowly increasing. Various β-lactamase genes are linked to a variety of genetic elements capable of horizontal DNA transfer. Consequently, their dissemination is likely and demands adequate risk management strategies.

A total of 627 E. coli isolates of which 373 produced an ESBL, collected across four continents, were screened using a O25b-ST131 clone allele-specific PCR for the pabB gene.

One hundred and forty-three ESBL isolates were found positive with the assay. These isolates were all of O25b type and, when studied by multilocus sequence typing (25 cases), were all of ST131. The O25b-ST131 clone was found to produce ESBLs other than CTX-M-15, specifically CTX-M-2, -3, -14, -27, -32 and -61 as well as TEM-24. This clone represents 3% of non-ESBL B2 isolates originating from urinary tract infections in Paris.

We have developed a PCR-based assay that easily identifies a clone with high likelihood of producing ESBLs, including CTX-M-15.

P. aeruginosa strains PA30 and PA431 were isolated from the sputa of cystic fibrosis patients and susceptibilities were determined by agar dilution. Isolates were genetically unrelated by PFGE analysis. Expression of efflux pumps, porins, a chromosomal cephalosporinase and a gene, glmS, previously implicated in hypersusceptibility were evaluated by real-time RT-PCR, outer membrane protein analysis and β-lactamase hydrolysis assays.

PA30 was hypersusceptible to β-lactams, fluoroquinolones and antimetabolites, with MICs at least 4-fold lower than those for the prototype strain PAO1, while PA431 was hypersusceptible to β-lactams and antimetabolites. Both isolates overproduced the porin OprF but showed down-regulation in the production of the carbapenem channel OprD despite carbapenem hypersusceptibility. PA30 had decreased expression of the mexAB–oprM pump involved with intrinsic antibiotic resistance but overexpressed the mexCD–oprJ and mexEF–oprN efflux systems normally associated with acquired resistance. PA431 showed down-regulation of oprM, the last gene in the mexAB–oprM operon, but overexpressed the mexXY pump. The ampC β-lactamase was weakly inducible in strain PA30, corresponding to cefoxitin hypersusceptibility.

The changes in expression of several intrinsic mechanisms in the hypersusceptible strains did not correlate with the observed phenotype. These data highlight the complex interactions of resistance mechanisms in P. aeruginosa and their roles in drug susceptibility.

Overall, 134 EAEC and 190 ETEC clinical isolates were studied. The MICs of ampicillin, chloramphenicol, nalidixic acid, tetracycline, trimethoprim/sulfamethoxazole, ciprofloxacin and amoxicillin/clavulanic acid were determined by the Etest method. Detection of mutations in the quinolone-resistance determining region of the gyrA and parC genes was performed by PCR and DNA sequencing.

When antimicrobial resistance in EAEC and ETEC isolates was compared between the two periods of time, a statistically significant increase in resistance (P < 0.01) was observed in EAEC for chloramphenicol and amoxicillin/clavulanic acid, whereas in ETEC it was for trimethoprim/sulfamethoxazole, nalidixic acid, ciprofloxacin and amoxicillin/clavulanic acid. Mutations in the gyrA gene were found in all nalidixic acid-resistant isolates, whereas mutation(s) in both gyrA and parC genes were found in the ciprofloxacin-resistant isolates.

The high percentage of resistance to quinolones in ETEC and EAEC isolated from travellers to North Africa and India is a matter for concern. These agents should therefore be used with caution in patients with traveller's diarrhoea returning from these geographical areas.

Eight independent lineages were founded from a common fluoroquinolone-susceptible L. pneumophila ancestor and propagated by serial passages in moxifloxacin-containing culture medium. We identified the substituted mutations that affected the DNA topoisomerase II-encoding genes, determined the order of substitution of the mutations leading to the stepwise MIC increases of moxifloxacin over evolutionary time and demonstrated their direct involvement in the resistance process.

Adaptation occurred through parallel stepwise increases in the moxifloxacin MICs up to 512-fold the MIC for the parental strain. Mutations affected the topoisomerase II-encoding genes gyrA, parC and gyrB, reflecting a high degree of genetic parallelism across the independent lineages. During evolution, the T83I change in GyrA occurred first, followed by G78D or S80R in ParC and D87N in GyrA, or S464Y or D426N in GyrB. By constructing isogenic strains, we showed that the progressive increase in resistance was linked to a precise order of mutation substitution, but also to the co-existence of several subpopulations of bacteria bearing different mutations.

Specific mutational trajectories were identified, strongly suggesting that intermolecular epistatic interactions between DNA topoisomerases underlie the mechanism of fluoroquinolone resistance in L. pneumophila. Our results suggest that L. pneumophila has strong potential to become resistant to fluoroquinolone compounds and warrant further investigation of resistance in clinical and environmental strains of this pathogen.

The Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP) data from 2001–07 were examined for emerging trends in azithromycin susceptibility. Further to the identification of six high-level azithromycin-resistant isolates in GRASP 2007, an additional 102 isolates were selected on the basis of azithromycin susceptibility and geographic origin from the GRASP 2006 and 2007 collections. Susceptibility testing by Etest and disc diffusion was performed on all 108 isolates and 75 of these were typed by N. gonorrhoeae multiantigen sequence typing.

A slight drift towards higher MICs of azithromycin was observed in the gonococcal population since 2001. Of greater concern was the first example of a shift to high-level resistance observed in six isolates in 2007. All six isolates were sequence type 649, which was not observed in any of the lower-level azithromycin-resistant isolates from 2007 or in any isolates tested from the same geographical locations. Contact tracing data for one patient suggested a link with Scotland. Disc diffusion testing of all 108 isolates showed that azithromycin, but not erythromycin, discs can differentiate between low-level and high-level resistance.

High-level azithromycin resistance has emerged in England and Wales. Contact tracing and typing data suggest this may have originated from Scotland. Surveillance of azithromycin resistance will be key in controlling its further dissemination.

We conducted a retrospective study of all non-pregnant adult patients with Listeria monocytogenes infection detected in sterile body fluids between 1983 and 2006. Early mortality was defined as death occurring between days 3 and 14 after admission, and late mortality as in-hospital death after 14 days.

Of 118 episodes, 16 were excluded because patients died in the first 48 h. Among the 102 patients analysed, 33 (32%) had received combined β-lactam and aminoglycoside therapy and 69 (68%) β-lactam monotherapy. Both groups had similar demographic and clinical features, and rate of appropriate initial therapy. Overall mortality was 21/102 (20.6%). Early overall mortality was 11.8%: 27.3% (9/33) in the combined group and 4.3% (3/69) in the monotherapy group (P = 0.003). Late mortality was 8.8%. In the multivariate analysis, the factors predicting early mortality were renal failure, previous corticosteroid therapy and age >65 years, whereas neoplastic disease and coma were associated with late mortality. Gentamicin administration did not decrease early mortality, but seemed to increase it. In the late mortality analysis, gentamicin use had no impact. In an analysis with the propensity score method for the use of aminoglycosides, combined therapy with this antibiotic was associated with an increasing trend for early mortality (OR 3.40, 95% CI 0.82–14.07).

The addition of aminoglycosides to treatment for listeriosis did not improve the patients' outcome.

Twenty-four patients with intractable MDR/XDR-TB were treated with a daily 300 mg dose of linezolid as part of their anti-TB drug regimen.

The patients were treated with linezolid for a median duration of 359 days [interquartile range (IQR) 268–443 days]. Seventeen (71%) patients received 300 mg of linezolid once daily from the beginning of treatment for a median duration of 289 days (IQR 233–405 days). Of these patients, four developed peripheral neuropathy, one of whom discontinued linezolid. In seven (29%) patients, 600 mg/day linezolid was administered initially for a median duration of 104 days (IQR 26–145 days) followed by 300 mg/day linezolid for a median duration of 348 days (IQR 298–427 days). In five of these seven patients, the reason for changing from 600 to 300 mg/day was due to side effects of 600 mg/day linezolid (peripheral neuropathy in four patients and leucopenia in one patient). After reducing the dose to 300 mg/day, linezolid could be continued in six of the seven patients. Negative sputum conversion was achieved in 22 (92%) patients after a median of 89 days from the start of linezolid treatment (IQR 48–160 days).

A daily 300 mg dose of linezolid may be useful for increasing the chances of culture conversion in the treatment of patients with intractable MDR/XDR-TB and might have fewer side effects, especially neurotoxicity, compared with a daily 600 mg dose of linezolid therapy. The present results encourage further research into the use of a 300 mg dose of linezolid for MDR/XDR-TB patients.

Female ICR mice were used in all experiments. An immunosuppressive state was induced in mice by an intraperitoneal injection of cyclophosphamide. Mice were intratracheally inoculated with Aspergillus fumigatus conidia, treated with micafungin, amphotericin B or both for 7 days, and were tested for their survival 20 days after the Aspergillus inoculation. Fungal burden in lungs, serum galactomannan index (GMI) and histopathology of lungs, spleen and kidneys were also evaluated.

Combination therapy with micafungin and amphotericin B gave excellent survival of infected mice compared with monotherapy with micafungin or amphotericin B alone. Combined therapy reduced the fungal burden in the lungs and the serum GM levels compared with monotherapy or untreated controls, resulting in a significant histological improvement with disappearance of fungi in the lungs.

These findings suggest that combination therapy with micafungin and amphotericin B is more effective compared with monotherapy with either of them alone for IPA treatment.

The MICs and biofilm eradication for two clinical isolates of Pseudomonas aeruginosa (a mucoid strain and a non-mucoid strain) were determined in the presence and absence of AlgL. The co-activity of aminoglycosides with DNase and/or AlgL against endogenous P. aeruginosa in cystic fibrosis (CF) sputum was also measured. The inhibitory effects of mucin in the presence and absence of the mucolytic agent NAC on aminoglycosidic activity were also examined.

The MIC values of the liposomal aminoglycosides were similar to or lower than those of free aminoglycosides. Biofilm formation increased the bactericidal concentrations of these drugs by 8- to 256-fold and treatment with AlgL improved killing of the mucoid strain. The activity of some aminoglycosides against the sputum was increased by the addition of DNase or AlgL (P < 0.05), and was increasingly evident with concurrent DNase and AlgL administration. Addition of mucin inhibited liposomal aminoglycosidic activity (up to 32-fold) evidently more than the free aminoglycosides (up to 8-fold). The addition of NAC did not improve activity significantly (P > 0.05). Tobramycin was the most effective aminoglycoside to reduce biofilms and sputum.

Liposomal aminoglycosides do not fare better than conventional forms. The co-administration of DNase and AlgL is essential for enhanced activity in reducing biofilm growth and sputum bacterial counts. While mucin retards bactericidal activity, NAC does not improve aminoglycosidic activity.

The expression of genes encoding the efflux pump AcrAB and the global regulators MarA, SoxS and RamA were examined and correlated with antimicrobial resistance.

Twenty isolates belonged to the two important clones representing KPC-possessing strains endemic to our region. Virtually all of these isolates had negligible or absent expression of the genes, and resistance to fluoroquinolones and aminoglycosides could be explained by alternative mechanisms. All of these isolates were susceptible to tigecycline. A group of 14 heterogeneous isolates was also examined. There was a correlation between expression of marA with expression of soxS. Only expression of soxS was significantly correlated with expression of acrB. With a background substitution in GyrA, increased expression of acrB and marA appeared to contribute to fluoroquinolone resistance in some isolates. A correlation was noted between expression of soxS and ramA (but not marA and acrB) and tigecycline MICs. Following in vitro exposure to tigecycline, resistance occurred in association with a marked increase in marA and acrB expression in isolates lacking expression of soxS and ramA.

While laboratory-derived tigecycline resistance was associated with increased acrB expression, the variation in tigecycline MICs in clinical isolates was associated only with selected regulator genes. It appears that other mechanisms beyond activation of the acrAB system mediate tigecycline resistance.

Case–comparison study of patients with ciprofloxacin-resistant and ciprofloxacin-susceptible Campylobacter infection conducted in Wales during 2003 and 2004.

Foreign travel was the major risk factor for ciprofloxacin-resistant infection [adjusted odds ratio (adjOR) 24.0, 95% confidence interval (95% CI) 12.6–45.9]. Among travellers, case patients were five times more likely to drink still bottled water (adjOR 4.7, 95% CI 1.0–21.7), whilst among non-travellers, case patients were three times more likely to drink sparkling bottled water (adjOR 3.3, 95% CI 1.5–7.4). There was no increased risk associated with eating poultry or prior quinolone use.

Foreign travel remains the most important risk factor for ciprofloxacin-resistant Campylobacter infection. The possible association of both domestic- and travel-related ciprofloxacin-resistant Campylobacter infection with bottled water needs to be further explored.

We used mutant prevention concentration (MPC) testing to define the risk of fluoroquinolone resistance induction in N. gonorrhoeae by ciprofloxacin, levofloxacin and moxifloxacin in a wild-type isolate (ATCC 49226) and its corresponding gyrA mutant (m-49226).

MIC/MPC values (mg/L) of ciprofloxacin, levofloxacin and moxifloxacin for ATCC 49226 were 0.0078/0.03125, 0.0078/0.125 and 0.0156/0.0625, respectively. The MIC of all fluoroquinolones for m-49226 was 0.125 mg/L; MPCs of ciprofloxacin, levofloxacin and moxifloxacin for this isolate were 4, 0.5 and 0.25 mg/L, respectively. Concentrations of all agents are predicted to exceed the MPC for ATCC 49226 for the entire dosage interval, while concentrations of moxifloxacin alone will exceed the MPC for m-49226. The hierarchy of tested agents with respect to %T_MSW [percentage of the dosage interval that concentrations fall within the mutant selection window (MSW)] for m-49226 was ciprofloxacin > levofloxacin > moxifloxacin. Multiple-dose fluoroquinolone regimens are predicted to achieve superior pharmacodynamics in comparison with single-dose regimens for m-49226, with increased AUC/MPC values and a reduced %T_MSW.

Evaluation of the use of moxifloxacin against N. gonorrhoeae is warranted, as is use of multiple-dose fluoroquinolone regimens.

MICs of 11 drugs for 10 MAP strains were determined using the MGIT system, the BACTEC^TM460TB system (BACTEC) and conventional agar dilution methods.

MICs determined by MGIT methods showed 80%–100% agreement (±1 log₂ dilution) with those determined by the BACTEC and agar dilution methods for ciprofloxacin, levofloxacin, azithromycin and clofazimine. The MGIT and BACTEC methods showed 70%, 80% and 90% agreement (±1 log₂ dilution) for MICs of ethambutol, rifabutin and rifampicin; agreement for all drugs increased to 100% at 2 log₂ dilution differences. For clarithromycin, the MGIT method had greater agreement with the agar dilution method (70% at the same dilution) than the BACTEC method (60% at ±1 log₂ dilution); agreement increased to 100% at ±2 log₂ dilutions in both cases. The MGIT and agar dilution methods agreed 60% and 100% for amikacin MICs at ±1 log₂ dilution and ±2 log₂ dilutions, respectively. By all methods MICs were higher than achievable serum concentrations for isoniazid and dapsone. There was 100% agreement between all three methods for azithromycin, clarithromycin and ciprofloxacin, and 80% agreement for rifampicin using published MIC thresholds available for M. avium complex strains.

This study shows that the MGIT system can be used for rapid and reliable drug susceptibility testing of MAP.

Two methicillin-susceptible S. aureus (MSSA), two community-associated (CA)-MRSA, one healthcare-associated (HA)-MRSA, three VISA and two VRSA were studied. The pharmacodynamic model was inoculated with a concentration of 1 x 10⁶ cfu/mL and ceftobiprole dosed every 8 h (at 0, 8 and 16 h) to simulate the fC_max and t_1/2 obtained after 500 mg intravenous (iv) every 8 h dosing (fC_max, 30 mg/L; t_1/2, 3.5 h). Vancomycin was dosed every 12 h (at 0 and 12 h) to simulate fC_max and t_1/2 obtained after 1 g iv every 12 h dosing (fC_max, 20 mg/L; t_1/2, 8 h). Samples were collected over 24 h to assess viable growth.

Ceftobiprole T > MIC of ≥100% (ceftobiprole MICs, ≤2 mg/L) was bactericidal (≥3 log₁₀ killing) against MSSA, CA-MRSA, HA-MRSA, VISA and VRSA at 16 and 24 h. Vancomycin fAUC₂₄/MIC of 340 (vancomycin MIC, 1 mg/L for MSSA and MRSA) resulted in a 1.8–2.6 log₁₀ reduction in colony count at 24 h. Vancomycin fAUC₂₄/MIC of 85–170 (vancomycin MIC, 2–4 mg/L for VISA) resulted in a 0.4–0.7 log₁₀ reduction at 24 h. Vancomycin fAUC₂₄/MIC of 5.3 (vancomycin MIC, 64 mg/L for VRSA) resulted in a limited effect.

Ceftobiprole T > MIC of ≥100% (ceftobiprole MICs, ≤2 mg/L) was bactericidal (≥3 log₁₀ killing) against MSSA, CA-MRSA, HA-MRSA, VISA and VRSA at 16 and 24 h. Vancomycin was bacteriostatic against MSSA, MRSA and VISA, while demonstrating no activity against VRSA.