Virologically controlled patients treated with lopinavir/ritonavir were included in a 48 week pilot trial during which lopinavir/ritonavir dosage was reduced if lopinavir concentration was >5000 ng/mL at inclusion. Serum lipids were longitudinally assessed and proviral DNA was quantified and sequenced in patients experiencing transient viraemia.

Thirty-three virologically suppressed patients while on a lopinavir/ritonavir-containing regimen were included, of whom 28 [20 males, mean age 44.6 years (SD 10.9)] completed the 48 week follow-up as scheduled. A significant decrease in lopinavir level was noted [mean C_min, 7363 ng/mL (min, 5118; max, 12 415) at baseline versus 4319 ng/mL (min, 1427; max, 8683) at week 48, P < 0.03]. A significant decrease in triglycerides was also observed [1.73 mmol/L (SD 1.08) at baseline versus 1.34 mmol/L (SD 0.91) at week 48, P = 0.03], whereas no significant change occurred for total, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol. In the 15 patients with transient viraemia, analysis of proviral DNA for antiretroviral resistance showed that mutations had occurred when compared with baseline genotypes in three patients: I47M (n = 2) and M46I (n = 1). Selection of these mutations was not associated with virological failure as all three patients had a sustained virological response without treatment modification after a 3 year follow-up.

This pilot study evaluating the biochemical and virological impact of a reduced dosing of lopinavir/ritonavir suggests that lower exposure to lopinavir/ritonavir could be associated with a significant decrease in triglycerides during treatment, without occurrence of resistance mutations that might impact the virological response to treatment.

Antibiotic susceptibility testing with mecillinam, meropenem, amoxicillin, co-amoxiclav, cefotaxime, piperacillin/tazobactam, ciprofloxacin, nitrofurantoin, trimethoprim and gentamicin was performed using the BSAC agar dilution method against 30 international strains of E. coli with known β-lactamase presence. Antibiotic susceptibility testing with mecillinam using the same method was performed against 325 regional isolates of E. coli resistant to third-generation cephalosporins.

The susceptibility results showed that the only antibiotics to which the 30 international isolates were consistently susceptible were mecillinam (100%) and meropenem (100%), irrespective of the presence of β-lactamases. Of the local isolates, 93.5% (304/325) were susceptible to mecillinam, having MICs < 8 mg/L.

Our results show that mecillinam has excellent in vitro activity against a range of E. coli exhibiting β-lactamase activity, some with the production of multiple β-lactamases. It is time to further evaluate the clinical utility of mecillinam in the treatment of infections caused by such organisms.

A prospective study was conducted on 621 patients, aged ≥ 18 years, hospitalized in a university-affiliated hospital in France, who received an IDS consultation between December 2007 and June 2008. The main outcome was early clinical improvement, and the secondary outcomes were length of stay and in-hospital mortality.

Adherence to the IDS's recommendations was 88.2% (548/621) for antimicrobial treatment and 72.2% (317/439) for diagnostic or monitoring tests. In a multivariable analysis, independent factors of adherence to therapeutic recommendations were a community-acquired infection [adjusted odds ratio (OR), 1.8; 95% confidence interval (CI), 1.1–3.0] and discontinuation or non-use of antibiotic treatment (adjusted OR, 9.7; 95% CI, 1.2–80.3). Adherence to recommendations for antibiotic treatment was associated with a higher rate of early clinical improvement (60.7% versus 43.9%, P = 0.01), shorter median length of stay (20 days versus 23 days, P = 0.03) and comparable in-hospital mortality (7.7% versus 5.5%, P = 0.50).

Factors associated with non-adherence must be anticipated by IDSs during consultations, because non-adherence leads to worse clinical outcomes. Further studies are needed to identify the interventions that could improve physician adherence to recommendations made during solicited consultations.

To examine the possible impact of ENF-cART on the risk of BP.

From the French Hospital Database on HIV, we selected two groups of patients among cART-treated patients who were prescribed a new cART regimen during the period 2001–2006, when their CD4 counts were <350 cells/mm³. The ENF-cART and cART groups consisted of 1220 and 9374 patients, respectively. Poisson regression models were used to quantify the relationship between ENF-cART therapy and the risk of BP.

At baseline the median CD4 counts were 100 and 211 cells/mm³ and the median plasma viral load (pVL) values were 60 276 and 2702 copies/mL in the ENF-cART and cART groups, respectively. The respective BP IRs were 0.65 [95% confidence interval (CI) 0.25–1.06] and 0.31 (95% CI 0.25–0.38) cases per 100 person-years. After adjustment for age, the HIV transmission group, the time period, co-trimoxazole prophylaxis, and stratified CD4 cell counts and pVL values, we found that the BP risk ratio was not increased by enfuvirtide treatment (relative rate 1.39; 95% CI 0.46–4.13). In contrast, lower CD4 cell counts and higher pVL values were significantly associated with a higher risk of BP.

ENF-cART is not associated with a significantly higher risk of BP than other cART regimens, although the value of the adjusted risk and the upper limit of the CI do not allow us to exclude a small increased risk.

A neutralization test was applied as a screening assay and a plaque reduction assay was used for confirmation. Expression plasmids for viral ribonucleoproteins (RNPs) and a plasmid that allowed expression of a pseudoviral reporter RNA were transfected into cells to investigate the effects of a novel antiviral compound on viral RNA synthesis.

BPR2-D2 was identified as a novel inhibitor against influenza virus from a hit obtained from high throughput screening of 20 000 or more compounds. BPR2-D2 exhibited an excellent antiviral efficacy for the oseltamivir-resistant virus (EC₅₀ ranging from 0.021 to 0.040 µM). No resistant virus was produced throughout 20 passages in the presence of BPR2-D2, whereas oseltamivir-resistant virus was generated at passage 8 using the same experimental system. A molecular target other than neuraminidase (NA) was found because BPR2-D2 inhibited the synthesis of viral RNA that was driven by influenza viral RNP in a transfection assay. BPR2-D2 also exhibited a broad antiviral spectrum against various strains of influenza A and influenza B viruses.

BPR2-D2 was identified as a novel inhibitor of influenza virus. It may target viral RNPs that are responsible for viral RNA synthesis. Targeting different molecules compared with NA allows BPR2-D2 to inhibit oseltamivir-resistant viruses.

Trained pharmacy assistants registered the sale of fluoroquinolones during February and March 2009 to outpatients in Moshi in all 14 pharmacies that are authorized to sell antibacterials for systemic use. The sale of all antibacterials of the Anatomical Therapeutic Chemical (ATC) J01 class was expressed in defined daily doses (DDDs) per 1000 inhabitants per day (DID). The availability of fluoroquinolones in drug outlets that are not authorized to sell antibacterials for systemic use was assessed in 15 randomly selected outlets in Moshi.

The sale of antibacterials to outpatients in Moshi by authorized pharmacies was 4.99 DID. The sale of fluoroquinolones was 0.62 DID (12% of total antibacterial sales). Ciprofloxacin was available in all 15 unauthorized drug outlets.

The substantial sales of fluoroquinolones by authorized pharmacies and the wide availability of fluoroquinolones in unauthorized drug outlets in Moshi constitute a challenge to the use of fluoroquinolones in TB treatment in Tanzania. Control of antibacterial use in Tanzania requires the implementation of surveillance systems for antibacterial use and resistance, and adequate restriction of antibacterial sales to authorized pharmacies only.

The intervention was performed on a 14 year baseline of monthly data on trimethoprim resistance and consumption. A three-parameter mathematical model was used to analyse the intervention effect. The prerequisites for reversion of resistance (i.e. fitness cost, associated resistance and clonal composition) were studied on subsets of consecutively collected Escherichia coli from urinary tract infections.

The use of trimethoprim-containing drugs decreased by 85% during the intervention. A marginal but statistically significant effect on the increase in trimethoprim resistance was registered. There was no change in the clonal composition of E. coli and there was no measurable fitness cost associated with trimethoprim resistance in clinical isolates. The frequency of associated antibiotic resistances in trimethoprim-resistant isolates was high.

A lack of detectable fitness cost of trimethoprim resistance in vitro together with a strong co-selection of other antibiotics could explain the rather disappointing effect of the intervention. The result emphasizes the low possibility of reverting antibiotic resistance once established and the urgent need for the development of new antibacterial agents.

Data from the Liverpool TDM (therapeutic drug monitoring) Registry were linked with the UK Collaborative HIV Cohort (CHIC) study. For each patient, the first measurement of lopinavir (twice daily) or atazanavir [once daily, ritonavir boosted (/r) or unboosted] plasma concentration was included. Linear regression was used to evaluate the association of dose, gender, age, weight, ethnicity and concomitant antiretroviral drugs or rifabutin with log-transformed drug concentration, adjusted for time since last intake.

Data from 439 patients on lopinavir (69% 400 mg/r, 31% 533 mg/r; 3% concomitant rifabutin) and 313 on atazanavir (60% 300 mg/r, 32% 400 mg/r, 8% 400 mg) were included. Multivariable models revealed the following predictors for lopinavir concentration: weight (11% decrease per additional 10 kg; P = 0.001); dose (25% increase for 533 mg/r; P = 0.024); and rifabutin (116% increase; P < 0.001). For atazanavir the predictors were dose (compared with 300 mg/r: 40% increase for 400 mg/r, 67% decrease for 400 mg; overall P < 0.001) and efavirenz (32% decrease; P = 0.016) but not tenofovir (P = 0.54).

This analysis confirms that efavirenz decreases atazanavir concentrations, and there was a negative association of weight and lopinavir concentrations. The strong impact of rifabutin on lopinavir concentration should be studied further.

The C. albicans CAI-4 strain carrying transcriptional fusions of the TRR1p, YHB1p and GRE2p genes to the Renilla reniformis luciferase LUC gene was pre-treated with subinhibitory concentrations of fluconazole and incubated with oxidants (diamide and hydrogen peroxide) or with the myelomonocytic cell line HL-60.

Fluconazole induced oxidative and nitrosative stress in a time- and dose-dependent manner as determined using oxidative- and nitrosative-specific gene reporters. At subinhibitory concentrations, fluconazole was able to induce protection in vitro to subsequent challenges with oxidants in both liquid and solid media, and also induced partial protection against the oxidative-mediated killing mechanisms of the myelocytic HL-60 cells.

Subinhibitory concentrations of fluconazole protect against oxidants and killing mediated by phagocytes.

The killing kinetics of XF-70, XF-73 and various comparator agents against exponential phase cultures of S. aureus SH1000 were compared with effects on cells held at 4°C, non-growing cultures expressing the stringent response induced by mupirocin and bacteria in the stationary phase. Biofilms of S. aureus SH1000 were generated with the Calgary device to examine the activities of XF-70 and XF-73 under a further system exhibiting diminished bacterial growth.

Cold culture, stringent response and stationary phase cultures remained susceptible to XF-70 and XF-73, which caused ≥5 log reductions in viability over 2 h. During this period the most active comparator agents (chlorhexidine and cetyltrimethylammonium bromide) only promoted a 3 log drop in viability. XF-70 and XF-73 were also highly active against biofilms, with both agents exhibiting low biofilm MICs (1 mg/L) and minimum biofilm eradication concentrations (2 mg/L).

XF-70 and XF-73 remained highly active against various forms of slow-growing or non-dividing S. aureus. The results support the hypothesis that membrane-active agents may be particularly effective in eradicating slow- or non-growing bacteria and suggest that XF-70 and XF-73 could be utilized to treat staphylococcal infections where the organisms are only dividing slowly, such as biofilm-associated infections of prosthetic devices.

One thousand four hundred and forty M. catarrhalis isolates originating from seven world regions were investigated. The isolates were recovered from 411 children <5 years of age and 1029 adults >20 years of age. PCR-restriction fragment length polymorphism (RFLP) was performed to determine bro prevalence and to distinguish between bro types. MIC values of 12 different antibiotics were determined using the CLSI (formerly NCCLS) broth microdilution method.

Of the 1440 isolates, 1313 (91%) possessed the bro-1 gene and 64 (4%) possessed the bro-2 gene. Additionally, the prevalence of bro positivity between the child and adult age groups was significantly different (P < 0.0001), though bro-1 and bro-2 prevalences within age groups were not significantly different. Consistently higher β-lactam MICs were observed for M. catarrhalis isolates originating in the Far East. Significant correlations in MICs were observed for several antibiotic combinations, including all five β-lactams with each other, and among the two quinolones.

The worldwide prevalence of bro gene carriage in clinical isolates of M. catarrhalis is now approaching 95%, with children significantly more likely to harbour bro-positive isolates than adults. Further, statistically significant differences in the distribution of β-lactam MICs were observed between different world regions, particularly with respect to the Far East.

Laboratory-derived S. aureus strains were generated under selection using a variety of cell-wall-active antibiotics. Complete sequences of 27 genes, including 17 two-component histidine kinase sensors, were then compared with those of their susceptible parent strain. Further genetic analysis was performed on 125 clinical S. aureus isolates and 42 geographically diverse isolates of vancomycin-intermediate S. aureus (VISA).

Selective pressure using imipenem resulted in single point mutations leading to amino acid substitutions in two genes: vraS, encoding a two-component histidine kinase sensor; and SA1702 (also called yvqF, located immediately upstream of vraS), encoding a conserved hypothetical protein. The accumulation of the mutation in two distinct proteins—MsrR, a peptide methionine sulphoxide reductase regulator, and TcaA, a teicoplanin-resistance-associated protein—correlated with further increases in the glycopeptide MIC. The prevalence of YvqF/VraSR mutants among 125 clinical isolates along with the corresponding teicoplanin MICs was as follows: 0% (0/39), ≤1 mg/L; 48.6% (17/35), 2 mg/L; 72.7% (24/33), 4 mg/L; 93.8% (15/16), 8 mg/L; and 100% (2/2), 16 mg/L. Genetic analysis of 42 VISA isolates also identified the predominant amino acid substitutions in YvqF/VraS: 9 isolates (21.4%) revealed mutations in YvqF, followed by 7 isolates with mutations in VraS (16.7%).

Our findings provide novel insights into the high prevalence and genetic diversity of YvqF/VraSR mutants among clinical S. aureus isolates with reduced susceptibility to teicoplanin.

In an earlier randomized, double blind study of liposomal amphotericin as initial therapy for invasive filamentous fungal infection (IFFI), a 3 mg/kg/day dose had a favourable overall response rate of 50% and 12 week survival rate of 72%. No improved outcome was seen with 10 mg/kg/day for the first 14 days. The study population was further analysed for the effect of prior azole exposure on treatment responses to liposomal amphotericin B. The protocol allowed prior treatment with azoles for prophylaxis or empirical therapy, and for up to 4 days for the confirmed IFFI before starting liposomal amphotericin B. Outcomes were compared for subsets of patients based on receipt of any azole and receipt of voriconazole during the 30 day screening period prior to study treatment.

Of 201 patients with data review board-confirmed IFFI, 116 (57.7%) received prior azoles and 36 (17.9%) received prior voriconazole. Favourable responses were achieved in 57 (49.1%) patients with prior azole exposure, in 39 (45.9%) without prior azole and in 13 (36.1%) with prior voriconazole. Numbers of patients alive at 12 weeks were 74 (63.8%) with any prior azole, 56 (65.9%) without prior azole and 26 (72.2%) after prior voriconazole. No differences were statistically significant.

Prior treatment with any azole or specifically with voriconazole did not seem to impact on overall response or survival in patients treated with liposomal amphotericin B for confirmed IFFI.

PVL-MRSA from community-based and hospitalized patients located across England were identified by PCR. Isolates were characterized via MIC determinations, toxin gene profiling, PFGE, SCCmec, spa and agr typing. Multilocus sequence typing (MLST) was performed on selected isolates. Patient demographic and available disease data were retained for analysis.

Seventy-six PVL-MRSA isolates resistant to three further classes of antibiotic were identified between 2005 and 2008 from centres in each of the Health Protection Agency's geographic regions in England. Patient demographics were typical for PVL-MRSA, and some travel associations were identified along with clonal spread. One instance of familial transmission in the community was detected. PVL-MRSA belonging to MLST clonal complex (CC) 1 (sequence type 772) were consistently highly resistant; multiply antibiotic-resistant representatives of CCs 5, 8, 22, 59 and 80 were also identified. Ciprofloxacin resistance was common amongst the study isolates (51 of 76 isolates).

Genetically diverse multiply antibiotic-resistant PVL-MRSA were identified, and included representatives of a recently emerged multiresistant clone (dubbed the Bengal Bay clone). Risk factors and disease presentations were typical for PVL-MRSA infections. This work highlights the diminishing utility of ciprofloxacin susceptibility for putative identification of PVL-MRSA.

Electronically prescribed doses of systemic antibacterials administered in this trust during 2008 were analysed in order to generate 10 indices of antimicrobial use for each of 14 departments. These indices were five measurements of consumption (DDDs, agent days, courses, antibiotic days and treatment periods) each denominated by two measurements of activity [bed days and finished consultant episodes (FCEs)].

The 10 indices cluster into four groups within which they correlate well but between which correlation is poor. These four groups comprise a volume-related measurement of consumption (DDDs, agent days, antibiotic days) and an exposure-related measurement of consumption (courses, treatment periods), each denominated by either bed occupancy (bed days) or patient throughput (FCEs).

Indices within these four groups seem to provide different and complementary information. Restricting measurement of antimicrobial use to a single metric such as DDDs per 1000 bed days may be insufficient. It is not known which (if any) of these indices are the best predictors of antimicrobial-related risks such as resistance pressure or Clostridium difficile infection.

PMOs with identical 11-base sequence (AcpP) targeted to acpP (an essential gene) of Escherichia coli were synthesized with various numbers of either piperazine (Pip) or N-(6-guanidinohexanoyl)piperazine (Gux) coupled to the phosphorodiamidate linker. Peptide–PMO conjugates were made using the membrane-penetrating peptide (RXR)₄XB (X is 6-aminohexanoic acid; B is β-alanine).

MICs (µM/mg/L) were measured using E. coli: 3 + Pip–AcpP, 160/653; 6 + Pip–AcpP, 160/673; 2 + Gux–AcpP, 20/88; 5 + Gux–AcpP, 10/49; 8 + Gux–AcpP, 10/56; 3 + Pip–AcpP–(RXR)₄XB, 0.3/2; and 5 + Gux–AcpP–(RXR)₄XB, 0.6/4. In cell-free protein synthesis reactions, all PMOs inhibited gene expression approximately the same. These results suggested that Pip–PMOs inefficiently penetrated the outer membrane. Indeed, the MICs of 3 + Pip–AcpP and 6 + Pip–AcpP were reduced to 0.6 and 2.5 µM (1.2 and 10.5 mg/L), respectively, using as indicator a strain with a ‘leaky’ outer membrane. In vivo, mice were infected intraperitoneally with E. coli. Intraperitoneal treatment with 50 mg/kg 3 + Pip– AcpP, 15 mg/kg 5 + Gux–AcpP or 0.5 mg/kg 3 + Pip–AcpP–(RXR)₄XB, or subcutaneous treatment with 15 mg/kg 5 + Gux–AcpP or (RXR)₄XB–AcpP reduced bacteria in blood and increased survival.

Cationic PMOs inhibited bacterial growth in vitro and in vivo, and Gux–PMOs were more effective than Pip–PMOs. However, neither was as effective as the equivalent PMO–peptide conjugates. Subcutaneous treatment showed that 5 + Gux–AcpP or (RXR)₄XB–AcpP entered the circulatory system, reduced infection and increased survival.

Multivariable models were developed to describe macrolide defined daily doses per capita.

Use was highest during October to March for all macrolides. Investigated yearly and provincial patterns differed considerably among the macrolide agents. Associations with socioeconomic variables were similar between clarithromycin and erythromycin, while azithromycin consumption showed some differences in its association with these variables. Consistently, the rate of influenza was significantly associated with increased macrolide use. The influenza rate interacted with socioeconomic variables in some models; as the influenza rate increased, the greatest increase in demand for macrolides occurred in populations with high percentages of low-income individuals, high unemployment levels and low percentages of individuals with bachelor's degrees.

The impact of associations among macrolide consumption, influenza and socioeconomic factors may reflect inappropriate use of these agents to treat viral infections and/or prescribing for secondary infections, and knowledge of the virus versus bacteria problem and accessibility of healthcare. Further research surrounding differences in access to antimicrobial prescriptions and treatment options between advantaged and disadvantaged populations is suggested to further understand the dynamics of antimicrobial use in Canada.

Sixty-two B. melitensis strains, isolated from humans—most experiencing their first brucellosis episode—over an 11 year period in Spain, were genotyped by multiple locus variable analysis (MLVA-16) for future studies. In the present work, molecular screening was undertaken to detect the presence of rpoB and gyrA/gyrB/parC/parE mutations (previously described in in vitro Brucella spp. mutants) related to resistance to rifampicin and fluoroquinolones, respectively.

Sixty-two MLVA-16 genotypes were identified among the B. melitensis population, with genetic similarity values ranging from 32% to 94%. rpoB mutations related to rifampicin resistance (positions 154, 526, 536, 539, 541, 574) were not detected. Neither were changes in GyrA described in in vitro mutants (67, 71, 87, 91 and an insertion at 340) detected in these strains. All showed identical GyrA, GyrB, ParC and ParE sequences with respect to B. melitensis 16M, except for one strain (ciprofloxacin and moxifloxacin MICs 0.25–0.50 mg/L) that harboured the Val264Ala replacement outside the GyrA quinolone resistance-determining region (QRDR); no differences were seen, however, in the NorMI/II efflux pump genes.

The absence of rpoB mutations clearly related to rifampicin resistance in clinical B. melitensis strains reinforces the first-choice status of this antibiotic in the treatment of first brucellosis episodes, and demonstrates the usefulness of molecular screening for resistant genotypes. The absence of topoisomerase II–IV mutations, however, cannot rule out fluoroquinolone resistance due to the interplay of different mechanisms.

Three hundred and fifteen isolates of Pseudomonas aeruginosa were submitted for testing. MICs of 14 antimicrobials were determined using the Etest and the results categorized using CLSI guidelines. Usually, six antimicrobial pairs were tested in combination also using the Etest. The results were assessed using the fractional inhibitory concentration index (FICI) and also by a novel parameter, the SBPI.

Some 4173 MICs and 1663 combination pairs were performed. The most active individual antimicrobials were colistin, tobramycin and amikacin, with 84%, 69% and 32% of isolates susceptible, respectively. Twenty-eight of 44 antimicrobial combinations were tested >10 times. Of the combinations, 3.6% were synergistic (FICI ≤ 0.5) and 0.1% were antagonistic (FICI > 4.0). Amikacin + ceftazidime (17%), ciprofloxacin + ceftazidime (12.9%) and ciprofloxacin + piperacillin/tazobactam (12%) were the most synergistic combinations. By median SBPI, the most effective combinations in vitro were colistin + ticarcillin/clavulanate, colistin + piperacillin/tazobactam and colistin + meropenem.

The Etest is a useful tool for determining MICs and testing antimicrobial combinations. The SBPI is more discriminatory than the FICI, allowing easy ranking of the combinations, and is likely to have clinical relevance.