I M Gould

University of Aberdeen, Aberdeen, Scotland, United Kingdom

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Publications (176)799.51 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Meticillin-resistant Staphylococcus aureus (MRSA) infection continues to be a substantial global problem with significant associated morbidity and mortality. This review summarises the discussions that took place at the 4th MRSA Consensus Conference in relation to the current treatment options for serious MRSA infections and how to optimise whichever therapy is embarked upon. It highlights the many challenges faced by both the laboratory and clinicians in the diagnosis and treatment of MRSA infections.
    Journal of Global Antimicrobial Resistance. 09/2014;
  • Deirdre J O'Brien, Ian M Gould
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    ABSTRACT: Despite concerns regarding efficacy and tolerability, vancomycin continues to be the standard treatment for skin and soft tissue infections (SSTIs) when β-lactam antimicrobials cannot be used. This review sought to establish the role of both old and new alternatives to vancomycin. Methods for achieving optimization of vancomycin therapy are also explored. Several meta-analyses have demonstrated poorer clinical outcomes when the vancomycin minimum inhibitory concentration approaches the breakpoint of 2 μg/ml. Higher doses should be utilized to optimize pharmacokinetics and pharmacodynamics when higher volumes of distribution occur (e.g. sepsis).Newer agents with established noninferiority to vancomycin include the oxazolidinones linezolid and tedizolid, the lipopeptide daptomycin, the anti-meticillin-resistant Staphylococcus aureus cephalosporin ceftaroline and the glycylcycline tigecycline. Linezolid is thus far the only agent that has been shown to be associated with better clinical and microbiological cure rates. Ceftaroline and tigecycline are broad-spectrum agents best reserved for polymicrobial infections (e.g. diabetic foot infections). When vancomycin is used for the treatment of SSTIs, maximizing the dose should be performed to improve efficacy. Cost is often the main limiting factor with regard to the newer agents, but their suitability for outpatient antimicrobial therapy may counteract this.
    Current Opinion in Infectious Diseases 02/2014; · 5.03 Impact Factor
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    ABSTRACT: The causes of antibiotic resistance are complex and include human behaviour at many levels of society; the consequences affect everybody in the world. Similarities with climate change are evident. Many efforts have been made to describe the many different facets of antibiotic resistance and the interventions needed to meet the challenge. However, coordinated action is largely absent, especially at the political level, both nationally and internationally. Antibiotics paved the way for unprecedented medical and societal developments, and are today indispensible in all health systems. Achievements in modern medicine, such as major surgery, organ transplantation, treatment of preterm babies, and cancer chemotherapy, which we today take for granted, would not be possible without access to effective treatment for bacterial infections. Within just a few years, we might be faced with dire setbacks, medically, socially, and economically, unless real and unprecedented global coordinated actions are immediately taken. Here, we describe the global situation of antibiotic resistance, its major causes and consequences, and identify key areas in which action is urgently needed.
    The Lancet Infectious Diseases 11/2013; · 19.97 Impact Factor
  • Deirdre J O'Brien, Ian M Gould
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    ABSTRACT: The decline in the development and approval of new antimicrobial agents, especially those with activity against multidrug-resistant Gram-negative bacteria, has arisen as one of the major public health threats of the 21st century. Antimicrobial stewardship has emerged as a key available means to attenuate this threat. Because of the immediacy of the crisis imposed by the dearth of new antimicrobial agents, this review aims to seek out innovative mechanisms that could complement existing programmes to maximize their effectiveness. Provision of expedited microbiological identification and susceptibility profiles utilizing molecular diagnostic techniques are means that are showing promise in complementing existing stewardship interventions. Biomarkers such as procalcitonin that facilitate clinical decision-making processes in discriminating between noninfectious causes masquerading as sepsis can assist in withholding or earlier discontinuation of antimicrobial agents. Seasonal influenza and polyvalent pneumococcal vaccine have a role to play by preventing secondary bacterial infections. Electronic learning tools are a means of disseminating information rapidly and universally. Coordinated national and international stewardship efforts play an essential role in promotion, engaging the public, and ensuring provision of sufficient resources. The safeguarding of antimicrobial agents for future generations is necessary, if we as a public do not wish to face a world without antibiotics. All potentially available resources must be recruited to order to protect antimicrobials. Robust methods of evaluating each of these interventions needs to be included from inception to evaluate which strategies are the most effective.
    Current Opinion in Infectious Diseases 08/2013; 26(4):352-358. · 5.03 Impact Factor
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    ABSTRACT: Daptomycin, a cyclic lipopeptide with rapid bactericidal activity, is approved at doses of 4mg/kg and 6mg/kg for the treatment of its respective indications [i.e. complicated skin and soft-tissue infections (cSSTIs) caused by Gram-positive bacteria; and Staphylococcus aureus bacteraemia associated with right-sided infective endocarditis (RIE) or cSSTIs, or RIE due to S. aureus]. Higher doses and combination therapy strategies have been investigated in some difficult-to-treat infections in order to: enhance clinical success rates; treat pathogens that may be non-susceptible to standard doses; and minimise the risk of resistance development in patients, particularly those who may need an extended treatment duration, who may have had suboptimal surgical management and/or who may have not responded to prior antibiotic therapy. Although clinical trial data of daptomycin doses >6mg/kg and of daptomycin in combination with other antibiotics are limited, clinical experience reported to date suggests that daptomycin is effective and well tolerated at higher doses and in combination. In this review, the rationale both for high-dose and combination therapy strategies with daptomycin is explored and the available evidence is presented by indication and evaluated from a clinical perspective. Safety and efficacy are discussed from prospective and retrospective clinical studies, together with case reports for a variety of infections, including bacteraemia, endocarditis, cSSTIs and osteomyelitis, and expert recommendations are provided in summary of the evidence. The use of high-dose daptomycin, alone or in combination, may be useful for difficult-to-treat Gram-positive infections and further evaluation of these strategies is warranted.
    International journal of antimicrobial agents 07/2013; · 3.03 Impact Factor
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    I.M. Gould
    International Journal of Antimicrobial Agents 06/2013; 41:S6. · 4.42 Impact Factor
  • I M Gould
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    ABSTRACT: Around the world, Staphylococcus aureus remains a dominant cause of bacteraemia. Whilst meticillin resistance remains the major phenotype of concern, various levels of reduced glycopeptide susceptibility are emerging with increasing frequency. The most common MRSA phenotypes now have raised vancomycin MICs within the susceptible range (MICs of 1-2mg/L). This phenomenon, known as MIC creep, is hotly contested and often denied. Key to detecting MIC creep may be to examine isolates fresh, as freezing can allow reversion to wild-type MIC, presumably by loss of mutations. Treatment failure is common with vancomycin and it is uncertain whether higher doses are beneficial. At the other extreme, when enough mutations have accumulated, full VISA status is achieved, although this can also be unstable on storage. Heteroresistant and VISA strains can be considered the inevitable end result of continued MIC creep and are even more likely to fail glycopeptide treatment. Currently full vancomycin resistance is uncommon, with only approximately 20 strains described and confirmed worldwide. Empirical treatment for patients with undefined Gram-positive sepsis can undoubtedly be improved by knowledge of MRSA status, so this is a potential advantage of hospital admission screening. If a patient is risk-assessed or screen-positive for MRSA, and infection is not serious, then vancomycin or teicoplanin is appropriate empirical therapy, providing loading doses are given to achieve therapeutic concentrations immediately (trough 15mg/L). For life-threatening infections, the glycopeptides are inadequate unless the isolate is likely to be fully susceptible (Etest<1.5mg/L). If not, daptomycin (8-10mg/L) can be used as monotherapy but the MIC should be measured as soon as possible.
    International journal of antimicrobial agents 05/2013; · 3.03 Impact Factor
  • Journal of Antimicrobial Chemotherapy 03/2013; · 5.34 Impact Factor
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    ABSTRACT: Infection with meticillin-resistant Staphylococcus aureus (MRSA) continues to have significant morbidity and mortality. Vancomycin, which has been the mainstay of treatment of invasive MRSA infections, has several drawbacks related to its pharmacological properties as well as varying degrees of emerging resistance. These resistant subpopulations are difficult to detect, making therapy with vancomycin less reliable. The newer agents such as linezolid, daptomycin, ceftaroline, and the newer glycopeptides telavancin and oritavancin are useful alternatives that could potentially replace vancomycin in the treatment of certain conditions. By summarising the discussions that took place at the III MRSA Consensus Conference in relation to the current place of vancomycin in therapy and the potential of the newer agents to replace vancomycin, this review focuses on the challenges faced by the laboratory and by clinicians in the diagnosis and treatment of MRSA infections.
    Journal of Global Antimicrobial Resistance. 03/2013; 1(1):23–30.
  • I.M. Gould
    Journal of Global Antimicrobial Resistance. 03/2013; 1(1):3.
  • Ian M. Gould
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    ABSTRACT: Recent evidence from publications describing the success of interventions to control hospital meticillin-resistant Staphylococcus aureus (MRSA), often in the endemic setting, is reviewed. Overall, there is cautious ground for optimism that MRSA can be controlled in a cost-effective manner by employing a bundle approach, the mainstay of which is widespread admission screening to inform patient-specific control measures.
    Journal of Global Antimicrobial Resistance. 03/2013; 1(1):43–45.
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    Ian M Gould, Abhijit M Bal
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    ABSTRACT: Bacterial resistance is a growing threat and yet few new antibiotics active against multi-resistant bacteria are being explored. A combination of falling profits, regulatory mechanisms and irrational and injudicious use of antibiotics has led to an alarming situation where some infections have no cure. In this article, we summarize the new developments that have been suggested to incentivize the pharmaceutical industries toward the field of infections. We also briefly mention the new compounds on the horizon and some newly approved compounds that might help us tide over this crisis.
    Virulence 01/2013; 4(2). · 2.79 Impact Factor
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    ABSTRACT: The widespread use of antibiotics in association with high-density clinical care has driven the emergence of drug-resistant bacteria that are adapted to thrive in hospitalised patients. Of particular concern are globally disseminated methicillin-resistant Staphylococcus aureus (MRSA) clones that cause outbreaks and epidemics associated with healthcare. The most rapidly spreading and tenacious healthcare-associated clone in Europe currently is EMRSA-15, a lineage that was first detected in the UK in the early 1990s and subsequently spread throughout Europe and beyond. To understand the genetic events that have accompanied the emergence of the EMRSA-15 pandemic, we obtained genome sequences for 193 isolates that were chosen for their geographical and temporal diversity, and belong to the same multilocus sequence type as EMRSA-15. Using phylogenomic methods, we were able to show that the current pandemic population of EMRSA-15 descends from a healthcare-associated MRSA epidemic that spread through England in the 1980s, which had itself previously emerged from a primarily community-associated methicillin-sensitive population. The emergence of fluoroquinolone resistance in this EMRSA-15 sub-clone in the English Midlands during the mid-1980s appears to have played a key role in triggering pandemic spread, and occurred shortly after the first clinical trials of this drug. Genome-based coalescence analysis estimated that the population of this sub-clone over the last twenty years has grown four times faster than its progenitor. Using comparative genomic analysis we were able to identify the molecular genetic basis of 99.8% of the antimicrobial resistance phenotypes of the isolates, highlighting the potential of pathogen genome sequencing as a diagnostic tool. We document the genetic changes associated with adaptation to the hospital environment and with increasing drug resistance over time, and how MRSA evolution likely has been influenced by country-specific drug use regimens.
    Genome Research 01/2013; · 14.40 Impact Factor
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    ABSTRACT: The International Society of Chemotherapy's Working Groups on Antibiotic Resistance and Antibiotic Stewardship convened a half-day workshop on the burden of multidrug-resistant organisms in the Asia-Pacific. This short review is a summary of their discussion and conclusions.
    Journal of Global Antimicrobial Resistance. 01/2013;
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    ABSTRACT: The prevalence of carbapenemase-producing Enterobacteriaceae (CPE) has increased during the past 10 years. Its detection is frequently difficult, because they do not always show a minimum inhibitory concentration (MIC) value for carbapenems in the resistance range. Both broth microdilution and agar dilution methods are more sensitive than disk diffusion method, Etest and automated systems. Studies on antimicrobial treatment are based on a limited number of patients; therefore, the optimal treatment is not well established. Combination therapy with two active drugs appears to be more effective than monotherapy. Combination of a carbapenem with another active agent - preferentially an aminoglycoside or colistin - could lower mortality provided that the MIC is ≤4 mg/l and probably ≤8 mg/l, and is administered in a higher-dose/prolonged-infusion regimen. An aggressive infection control and prevention strategy is recommended, including reinforcement of hand hygiene, using contact precautions and early detection of CPE through use of targeted surveillance.
    Journal of chemotherapy (Florence, Italy) 01/2013; 25(3):129-40. · 0.83 Impact Factor
  • David W Noble, Ian M Gould
    The Lancet Infectious Diseases 08/2012; 12(10):741-2. · 19.97 Impact Factor
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    ABSTRACT: Evidence is accumulating that active surveillance, when combined with appropriate infection control, is a successful measure for controlling hospital-acquired meticillin-resistant Staphylococcus aureus (MRSA). In this study, the impacts of a long-term control strategy of this type, including the use of chlorhexidine baths, on the clinical and molecular epidemiology of MRSA in the Intensive Care Unit of Aberdeen Royal Infirmary were investigated. Characterisation of 85 sequential index MRSA isolates was performed using phenotypic methods (biotyping), antibiotic susceptibility testing and three genotypic methods (pulsed-field gel electrophoresis, spa typing and multilocus sequence typing) over a 4-year period. There was no evidence of loss in effectiveness of the control strategy over the study period. Compliance with screening remained high (>85%) throughout and there was no significant increase in the prevalence of MRSA detected in surveillance (P=0.43 for trend) or clinical cultures (P=0.79). There were no significant trends in rates of other index surveillance organisms (P>0.5). Results of the three typing methods were in general agreement with three prevalent MRSA clones [clonal complex 22 (CC22), CC30 and CC45]. CC22 emerged as the dominant clonal complex alongside a significant decline in CC30 (P=0.002). CC45 was significantly more likely to be positive in glycopeptide resistance screens (P<0.001). There was no increase in antibiotic or chlorhexidine resistance. Long-term chlorhexidine bathing was not associated with any detectable loss of efficacy or increase in resistance in MRSA or with any increase in infection with other organisms. Changing clonal epidemiology occurred with no overall change in the prevalence of MRSA.
    International journal of antimicrobial agents 08/2012; 40(4):323-31. · 3.03 Impact Factor
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    ABSTRACT: To determine the proportion of methicillin-resistant Staphylococcus aureus (MRSA) detections identified by nasal swabbing using agar culture in comparison with multiple body site testing using agar and nutrient broth culture. Cross-sectional study. Adult patients admitted to 36 general specialty wards of 2 large hospitals in Scotland. Patients were screened for MRSA via multiple body site swabs (nasal, throat, axillary, perineal, and wound/invasive device sites) cultured individually on chromogenic agar and pooled in nutrient broth. Combined results from all sites and cultures provided a gold-standard estimate of true MRSA prevalence. This study found that nasal screening performed better than throat, axillary, or perineal screening but at best identified only 66% of true MRSA carriers against the gold standard at an overall prevalence of 2.9%. Axillary screening performed least well. Combining nasal and perineal swabs gave the best 2-site combination (82%). When combined with realistic screening compliance rates of 80%-90%, nasal swabbing alone probably detects just over half of true colonization in practice. Swabbing of clinically relevant sites (wounds, indwelling devices, etc) is important for a small but high-prevalence group. Nasal swabbing is the standard method in many locations for MRSA screening. Its diagnostic efficiency in practice appears to be limited, however, and the resource implications of multiple body site screening have to be balanced against a potential clinical benefit whose magnitude and nature remains unclear.
    Infection Control and Hospital Epidemiology 08/2012; 33(8):803-8. · 4.02 Impact Factor
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    ABSTRACT: By repeating Etests on 36 blood isolates of MRSA over 9 months we explored the effects of isolate storage on vancomycin and daptomycin MIC. We identified overall declines in vancomycin and daptomycin MIC taken from the same isolates at 3 monthly intervals (P <0.001). Declines ≥ 1 doubling dilution were observed in 75% and 67% of isolates for vancomycin and daptomycin MIC respectively. Effects of storage should be considered in evidence around MIC 'creep'.
    Journal of clinical microbiology 08/2012; 50(10):3383-7. · 4.16 Impact Factor
  • Ian M Gould
    International journal of antimicrobial agents 07/2012; 40(3):193-5. · 3.03 Impact Factor

Publication Stats

2k Citations
799.51 Total Impact Points

Institutions

  • 1991–2013
    • University of Aberdeen
      • • Health Services Research Unit
      • • Aberdeen Royal Infirmary
      Aberdeen, Scotland, United Kingdom
  • 2012
    • University of Strathclyde
      • Strathclyde Institute of Pharmacy and Biomedical Sciences
      Glasgow, SCT, United Kingdom
  • 2011
    • NHS Ayrshire and Arran
      Ayr, Scotland, United Kingdom
    • National Health Service
      • Department of Medical Microbiology
      Radditch, England, United Kingdom
  • 2009–2011
    • East Coast Community Healthcare CIC
      Beccles, England, United Kingdom
  • 2010
    • University Hospital Crosshouse
      Cill Mheàrnag, Scotland, United Kingdom
  • 2007
    • Institut de Recherche en Cancerologie de Montpellier
      Montpelhièr, Languedoc-Roussillon, France
  • 2006
    • The Bracton Centre, Oxleas NHS Trust
      Дартфорде, England, United Kingdom
    • Université Libre de Bruxelles
      • School of Public Health (ESP)
      Brussels, BRU, Belgium
  • 2004
    • Statens Serum Institut
      København, Capital Region, Denmark
  • 2000–2001
    • University of Trnava
      • Department of Public Health
      Nagyszombat, Trnavský, Slovakia
  • 1984–1997
    • The University of Edinburgh
      • Medical Genetics Unit
      Edinburgh, Scotland, United Kingdom
  • 1989–1995
    • Aberdeen City Council
      Aberdeen, Scotland, United Kingdom
  • 1994
    • The Robert Gordon University
      Aberdeen, Scotland, United Kingdom