Search tips
Search criteria

Results 1-22 (22)

Clipboard (0)

Select a Filter Below

more »
Year of Publication
more »
1.  What makes public health studies ethical? Dissolving the boundary between research and practice 
BMC Medical Ethics  2014;15:61.
The generation of evidence is integral to the work of public health and health service providers. Traditionally, ethics has been addressed differently in research projects, compared with other forms of evidence generation, such as quality improvement, program evaluation, and surveillance, with review of non-research activities falling outside the purview of the research ethics board. However, the boundaries between research and these other evaluative activities are not distinct. Efforts to delineate a boundary – whether on grounds of primary purpose, temporality, underlying legal authority, departure from usual practice, or direct benefits to participants – have been unsatisfactory.
Public Health Ontario has eschewed this distinction between research and other evaluative activities, choosing to adopt a common framework and process to guide ethical reflection on all public health evaluative projects throughout their lifecycle – from initial planning through to knowledge exchange.
The Public Health Ontario framework was developed by a working group of public health and ethics professionals and scholars, in consultation with individuals representing a wide range of public health roles. The first part of the framework interprets the existing Canadian research ethics policy statement (commonly known as the TCPS 2) through a public health lens. The second part consists of ten questions that guide the investigator in the application of the core ethical principles to public health initiatives.
The framework is intended for use by those designing and executing public health evaluations, as well as those charged with ethics review of projects. The goal is to move toward a culture of ethical integrity among investigators, reviewers and decision-makers, rather than mere compliance with rules. The framework is consonant with the perspective of the learning organization and is generalizable to other public health organizations, to health services organizations, and beyond.
Public Health Ontario has developed an ethics framework that is applicable to any evidence-generating activity, regardless of whether it is labelled research. While developed in a public health context, it is readily adaptable to other health services organizations and beyond.
PMCID: PMC4133954  PMID: 25104180
Ethics; Public health; Research; Quality improvement; Program evaluation
2.  Community-associated methicillin-resistant Staphylococcus aureus in northwest Ontario: A five-year report of incidence and antibiotic resistance 
The incidence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is traditionally high in remote areas of Canada with large Aboriginal populations. Northwestern Ontario is home to 28,000 First Nations people in more than 30 remote communities; rates of CA-MRSA are unknown.
To determine the CA-MRSA rates and antibiotic susceptibilities in this region.
A five-year review of laboratory and patient CA-MRSA data and antibiotic susceptibility was undertaken.
In 2012, 56% of S aureus isolates were CA-MRSA strains, an increase from 31% in 2008 (P=0.06). Reinfection rates have been increasing faster than new cases and, currrently, 25% of infections are reinfections. CA-MRSA isolates continue to be susceptible to many common antibiotics (nearly 100%), particularly trimethoprim/sulfamethoxazole, clindamycin and tetracycline. Erythromycin susceptibility stands at 58%.
Rates of CA-MRSA, as a percentage of all S aureus isolates, were higher than those reported in other primary care series. The infection rate per 100,000 is one the highest reported in Canada. Antibiotic susceptibilities were unchanged during the study period; the 99% susceptibility rate to clindamycin differs from a 2010 Vancouver (British Columbia) study that reported only a 79% susceptibility to this antibiotic.
There are very high rates of CA-MRSA infections in northwestern Ontario. Disease surveillance and ongoing attention to antibiotic resistance is important in understanding the changing profile of MRSA infections. Social determinants of health, specifically improved housing and sanitation, remain important regional issues.
PMCID: PMC3720013  PMID: 24421817
Aboriginal; Antibiotic susceptibility; CA-MRSA; Northwest Ontario
3.  Variability in research ethics review of cluster randomized trials: a scenario-based survey in three countries 
Trials  2014;15:48.
Cluster randomized trials (CRTs) present unique ethical challenges. In the absence of a uniform standard for their ethical design and conduct, problems such as variability in procedures and requirements by different research ethics committees will persist. We aimed to assess the need for ethics guidelines for CRTs among research ethics chairs internationally, investigate variability in procedures for research ethics review of CRTs within and among countries, and elicit research ethics chairs’ perspectives on specific ethical issues in CRTs, including the identification of research subjects. The proper identification of research subjects is a necessary requirement in the research ethics review process, to help ensure, on the one hand, that subjects are protected from harm and exploitation, and on the other, that reviews of CRTs are completed efficiently.
A web-based survey with closed- and open-ended questions was administered to research ethics chairs in Canada, the United States, and the United Kingdom. The survey presented three scenarios of CRTs involving cluster-level, professional-level, and individual-level interventions. For each scenario, a series of questions was posed with respect to the type of review required (full, expedited, or no review) and the identification of research subjects at cluster and individual levels.
A total of 189 (35%) of 542 chairs responded. Overall, 144 (84%, 95% CI 79 to 90%) agreed or strongly agreed that there is a need for ethics guidelines for CRTs and 158 (92%, 95% CI 88 to 96%) agreed or strongly agreed that research ethics committees could be better informed about distinct ethical issues surrounding CRTs. There was considerable variability among research ethics chairs with respect to the type of review required, as well as the identification of research subjects. The cluster-cluster and professional-cluster scenarios produced the most disagreement.
Research ethics committees identified a clear need for ethics guidelines for CRTs and education about distinct ethical issues in CRTs. There is disagreement among committees, even within the same countries, with respect to key questions in the ethics review of CRTs. This disagreement reflects variability of opinion and practices pointing toward possible gaps in knowledge, and supports the need for explicit guidelines for the ethical conduct and review of CRTs.
PMCID: PMC3925119  PMID: 24495542
Cluster randomized trials; Informed consent; Research ethics guidelines; Research ethics review; Web-based survey
4.  What is the role and authority of gatekeepers in cluster randomized trials in health research? 
Trials  2012;13:116.
This article is part of a series of papers examining ethical issues in cluster randomized trials (CRTs) in health research. In the introductory paper in this series, we set out six areas of inquiry that must be addressed if the CRT is to be set on a firm ethical foundation. This paper addresses the sixth of the questions posed, namely, what is the role and authority of gatekeepers in CRTs in health research? ‘Gatekeepers’ are individuals or bodies that represent the interests of cluster members, clusters, or organizations. The need for gatekeepers arose in response to the difficulties in obtaining informed consent because of cluster randomization, cluster-level interventions, and cluster size. In this paper, we call for a more restrictive understanding of the role and authority of gatekeepers.
Previous papers in this series have provided solutions to the challenges posed by informed consent in CRTs without the need to invoke gatekeepers. We considered that consent to randomization is not required when cluster members are approached for consent at the earliest opportunity and before any study interventions or data-collection procedures have started. Further, when cluster-level interventions or cluster size means that obtaining informed consent is not possible, a waiver of consent may be appropriate. In this paper, we suggest that the role of gatekeepers in protecting individual interests in CRTs should be limited. Generally, gatekeepers do not have the authority to provide proxy consent for cluster members. When a municipality or other community has a legitimate political authority that is empowered to make such decisions, cluster permission may be appropriate; however, gatekeepers may usefully protect cluster interests in other ways. Cluster consultation may ensure that the CRT addresses local health needs, and is conducted in accord with local values and customs. Gatekeepers may also play an important role in protecting the interests of organizations, such as hospitals, nursing homes, general practices, and schools. In these settings, permission to access the organization relies on resource implications and adherence to institutional policies.
PMCID: PMC3443001  PMID: 22834691
5.  When is informed consent required in cluster randomized trials in health research? 
Trials  2011;12:202.
This article is part of a series of papers examining ethical issues in cluster randomized trials (CRTs) in health research. In the introductory paper in this series, we set out six areas of inquiry that must be addressed if the cluster trial is to be set on a firm ethical foundation. This paper addresses the second of the questions posed, namely, from whom, when, and how must informed consent be obtained in CRTs in health research? The ethical principle of respect for persons implies that researchers are generally obligated to obtain the informed consent of research subjects. Aspects of CRT design, including cluster randomization, cluster level interventions, and cluster size, present challenges to obtaining informed consent. Here we address five questions related to consent and CRTs: How can a study proceed if informed consent is not possible? Is consent to randomization always required? What information must be disclosed to potential subjects if their cluster has already been randomized? Is passive consent a valid substitute for informed consent? Do health professionals have a moral obligation to participate as subjects in CRTs designed to improve professional practice?
We set out a framework based on the moral foundations of informed consent and international regulatory provisions to address each of these questions. First, when informed consent is not possible, a study may proceed if a research ethics committee is satisfied that conditions for a waiver of consent are satisfied. Second, informed consent to randomization may not be required if it is not possible to approach subjects at the time of randomization. Third, when potential subjects are approached after cluster randomization, they must be provided with a detailed description of the interventions in the trial arm to which their cluster has been randomized; detailed information on interventions in other trial arms need not be provided. Fourth, while passive consent may serve a variety of practical ends, it is not a substitute for valid informed consent. Fifth, while health professionals may have a moral obligation to participate as subjects in research, this does not diminish the necessity of informed consent to study participation.
PMCID: PMC3184061  PMID: 21906277
6.  Who is the research subject in cluster randomized trials in health research? 
Trials  2011;12:183.
This article is part of a series of papers examining ethical issues in cluster randomized trials (CRTs) in health research. In the introductory paper in this series, we set out six areas of inquiry that must be addressed if the CRT is to be set on a firm ethical foundation. This paper addresses the first of the questions posed, namely, who is the research subject in a CRT in health research? The identification of human research subjects is logically prior to the application of protections as set out in research ethics and regulation. Aspects of CRT design, including the fact that in a single study the units of randomization, experimentation, and observation may differ, complicate the identification of human research subjects. But the proper identification of human research subjects is important if they are to be protected from harm and exploitation, and if research ethics committees are to review CRTs efficiently.
We examine the research ethics literature and international regulations to identify the core features of human research subjects, and then unify these features under a single, comprehensive definition of human research subject. We define a human research subject as any person whose interests may be compromised as a result of interventions in a research study. Individuals are only human research subjects in CRTs if: (1) they are directly intervened upon by investigators; (2) they interact with investigators; (3) they are deliberately intervened upon via a manipulation of their environment that may compromise their interests; or (4) their identifiable private information is used to generate data. Individuals who are indirectly affected by CRT study interventions, including patients of healthcare providers participating in knowledge translation CRTs, are not human research subjects unless at least one of these conditions is met.
PMCID: PMC3162904  PMID: 21791064
7.  Inadequate reporting of research ethics review and informed consent in cluster randomised trials: review of random sample of published trials 
Objectives To investigate the extent to which authors of cluster randomised trials adhered to two basic requirements of the World Medical Association’s Declaration of Helsinki and the International Committee of Medical Journal Editors’ uniform requirements for manuscripts (namely, reporting of research ethics review and informed consent), to determine whether the adequacy of reporting has improved over time, and to identify characteristics of cluster randomised trials associated with reporting of ethics practices.
Design Review of a random sample of published cluster randomised trials from an electronic search in Medline.
Setting Cluster randomised trials in health research published in English language journals from 2000 to 2008.
Study sample 300 cluster randomised trials published in 150 journals.
Results 77 (26%, 95% confidence interval 21% to 31%) trials failed to report ethics review. The proportion reporting ethics review increased significantly over time (P<0.001). Trials with data collection interventions at the individual level were more likely to report ethics review than were trials that used routine data sources only (79% (n=151) v 55% (23); P=0.008). Trials that accounted for clustering in the design and analysis were more likely to report ethics review. The median impact factor of the journal of publication was higher for trials that reported ethics review (3.4 v 2.3; P<0.001). 93 (31%, 26% to 36%) trials failed to report consent. Reporting of consent increased significantly over time (P<0.001). Trials with interventions targeting participants at the individual level were more likely to report consent than were trials with interventions targeting the cluster level (87% (90) v 48% (41); P<0.001). Trials with data collection interventions at the individual level were more likely to report consent than were those that used routine data sources only (78% (146) v 29% (11); P<0.001).
Conclusions Reporting of research ethics protections in cluster randomised trials is inadequate. In addition to research ethics approval, authors should report whether informed consent was sought, from whom consent was sought, and what consent was for.
PMCID: PMC3092521  PMID: 21562003
8.  Does clinical equipoise apply to cluster randomized trials in health research? 
Trials  2011;12:118.
This article is part of a series of papers examining ethical issues in cluster randomized trials (CRTs) in health research. In the introductory paper in this series, Weijer and colleagues set out six areas of inquiry that must be addressed if the cluster trial is to be set on a firm ethical foundation. This paper addresses the third of the questions posed, namely, does clinical equipoise apply to CRTs in health research? The ethical principle of beneficence is the moral obligation not to harm needlessly and, when possible, to promote the welfare of research subjects. Two related ethical problems have been discussed in the CRT literature. First, are control groups that receive only usual care unduly disadvantaged? Second, when accumulating data suggests the superiority of one intervention in a trial, is there an ethical obligation to act?
In individually randomized trials involving patients, similar questions are addressed by the concept of clinical equipoise, that is, the ethical requirement that, at the start of a trial, there be a state of honest, professional disagreement in the community of expert practitioners as to the preferred treatment. Since CRTs may not involve physician-researchers and patient-subjects, the applicability of clinical equipoise to CRTs is uncertain. Here we argue that clinical equipoise may be usefully grounded in a trust relationship between the state and research subjects, and, as a result, clinical equipoise is applicable to CRTs. Clinical equipoise is used to argue that control groups receiving only usual care are not disadvantaged so long as the evidence supporting the experimental and control interventions is such that experts would disagree as to which is preferred. Further, while data accumulating during the course of a CRT may favor one intervention over another, clinical equipoise supports continuing the trial until the results are likely to be broadly convincing, often coinciding with the planned completion of the trial. Finally, clinical equipoise provides research ethics committees with formal and procedural guidelines that form an important part of the assessment of the benefits and harms of CRTs in health research.
PMCID: PMC3113987  PMID: 21569349
9.  Ethical issues posed by cluster randomized trials in health research 
Trials  2011;12:100.
The cluster randomized trial (CRT) is used increasingly in knowledge translation research, quality improvement research, community based intervention studies, public health research, and research in developing countries. However, cluster trials raise difficult ethical issues that challenge researchers, research ethics committees, regulators, and sponsors as they seek to fulfill responsibly their respective roles. Our project will provide a systematic analysis of the ethics of cluster trials. Here we have outlined a series of six areas of inquiry that must be addressed if the cluster trial is to be set on a firm ethical foundation:
1. Who is a research subject?
2. From whom, how, and when must informed consent be obtained?
3. Does clinical equipoise apply to CRTs?
4. How do we determine if the benefits outweigh the risks of CRTs?
5. How ought vulnerable groups be protected in CRTs?
6. Who are gatekeepers and what are their responsibilities?
Subsequent papers in this series will address each of these areas, clarifying the ethical issues at stake and, where possible, arguing for a preferred solution. Our hope is that these papers will serve as the basis for the creation of international ethical guidelines for the design and conduct of cluster randomized trials.
PMCID: PMC3107798  PMID: 21507237
10.  Whipple’s disease with constrictive pericarditis: A rare disease with a rare presentation 
Whipple’s disease is a multisystem disease that can affect the heart with predominantly endocardial and pericardial involvement and, less often, myocardial inflammation. Previously diagnosed at autopsy, cardiac involvement in Whipple’s disease is being recognized clinically more often. A 58-year-old man with Whipple’s-related constrictive pericarditis, arthralgias and lymphadenopathy is described. He underwent antibiotic treatment and pericardiectomy with improvement in his clinical state.
PMCID: PMC2691706  PMID: 19279994
Constrictive pericarditis; Jejunal biopsy; Lymphadenopathy; Pericardiectomy; Whipple’s disease
11.  Ethical and policy issues in cluster randomized trials: rationale and design of a mixed methods research study 
Trials  2009;10:61.
Cluster randomized trials are an increasingly important methodological tool in health research. In cluster randomized trials, intact social units or groups of individuals, such as medical practices, schools, or entire communities – rather than individual themselves – are randomly allocated to intervention or control conditions, while outcomes are then observed on individual cluster members. The substantial methodological differences between cluster randomized trials and conventional randomized trials pose serious challenges to the current conceptual framework for research ethics. The ethical implications of randomizing groups rather than individuals are not addressed in current research ethics guidelines, nor have they even been thoroughly explored. The main objectives of this research are to: (1) identify ethical issues arising in cluster trials and learn how they are currently being addressed; (2) understand how ethics reviews of cluster trials are carried out in different countries (Canada, the USA and the UK); (3) elicit the views and experiences of trial participants and cluster representatives; (4) develop well-grounded guidelines for the ethical conduct and review of cluster trials by conducting an extensive ethical analysis and organizing a consensus process; (5) disseminate the guidelines to researchers, research ethics boards (REBs), journal editors, and research funders.
We will use a mixed-methods (qualitative and quantitative) approach incorporating both empirical and conceptual work. Empirical work will include a systematic review of a random sample of published trials, a survey and in-depth interviews with trialists, a survey of REBs, and in-depth interviews and focus group discussions with trial participants and gatekeepers. The empirical work will inform the concurrent ethical analysis which will lead to a guidance document laying out principles, policy options, and rationale for proposed guidelines. An Expert Panel of researchers, ethicists, health lawyers, consumer advocates, REB members, and representatives from low-middle income countries will be appointed. A consensus conference will be convened and draft guidelines will be generated by the Panel; an e-consultation phase will then be launched to invite comments from the broader community of researchers, policy-makers, and the public before a final set of guidelines is generated by the Panel and widely disseminated by the research team.
PMCID: PMC2725043  PMID: 19638233
12.  Research ethics review: Do it once and do it well 
PMCID: PMC2653580  PMID: 19289798
14.  Can patient decision aids help people make good decisions about participating in clinical trials? A study protocol 
Evidence shows that the standard process for obtaining informed consent in clinical trials can be inadequate, with study participants frequently not understanding even basic information fundamental to giving informed consent. Patient decision aids are effective decision support tools originally designed to help patients make difficult treatment or screening decisions. We propose that incorporating decision aids into the informed consent process will improve the extent to which participants make decisions that are informed and consistent with their preferences. A mixed methods study will test this proposal.
Phase one of this project will involve assessment of a stratified random sample of 50 consent documents from recently completed investigator-initiated clinical trials, according to existing standards for supporting good decision making. Phase two will involve interviews of a purposive sample of 50 trial participants (10 participants from each of five different clinical areas) about their experience of the informed consent process, and how it could be improved. In phase three, we will convert consent forms for two completed clinical trials into decision aids and pilot test these new tools using a user-centered design approach, an iterative development process commonly employed in computer usability literature. In phase four, we will conduct a pilot observational study comparing the new tools to standard consent forms, with potential recruits to two hypothetical clinical trials. Outcomes will include knowledge of key aspects of the decision, knowledge of the probabilities of different outcomes, decisional conflict, the hypothetical participation decision, and qualitative impressions of the experience.
This work will provide initial evidence about whether a patient decision aid can improve the informed consent process. The larger goal of this work is to examine whether study recruitment can be improved from (barely) informed consent based on disclosure-oriented documents, towards a process of high-quality participant decision-making.
PMCID: PMC2517068  PMID: 18651981
15.  Home-based intermediate care program vs hospitalization 
Canadian Family Physician  2008;54(1):66-73.
To explore whether a home-based intermediate care program in a large Canadian city lowers the cost of care and to look at whether such home-based programs could be a solution to the increasing demands on Canadian hospitals.
Single-arm study with historical controls.
Department of Family Medicine at the Ottawa Hospital (Civic campus) in Ontario.
Patients requiring hospitalization for acute care. Participants were matched with historical controls based on case-mix, most responsible diagnosis, and level of complexity.
Placement in the home-based intermediate care program. Daily home visits from the nurse practitioner and 24-hour access to care by telephone.
Multivariate regression models were used to estimate the effect of the program on 5 outcomes: length of stay in hospital, cost of care substituted for hospitalization (Canadian dollars), readmission for a related diagnosis, readmission for any diagnosis, and costs incurred by community home-care services for patients following discharge from hospital.
The outcomes of 43 hospital admissions were matched with those of 363 controls. Patients enrolled in the program stayed longer in hospital (coefficient 3.3 days, P < .001), used more community care services following discharge (coefficient $729, P = .007), and were more likely to be readmitted to hospital within 3 months of discharge (coefficient 17%, P = .012) than patients treated in hospital. Total substituted costs of home-based care were not significantly different from the costs of hospitalization (coefficient -$501, P = .11).
While estimated cost savings were not statistically significant, the limitations of our study suggest that we underestimated these savings. In particular, the economic inefficiencies of a small immature program and the inability to control for certain factors when selecting historical controls affected our results. Further research is needed to determine the economic effect of mature home-based programs.
PMCID: PMC2293319  PMID: 18208958
16.  Patient, informal caregiver and care provider acceptance of a hospital in the home program in Ontario, Canada 
Hospital in the home programs have been implemented in several countries and have been shown to be safe substitutions (alternatives) to in-patient hospitalization. These programs may offer a solution to the increasing demands made on tertiary care facilities and to surge capacity. We investigated the acceptance of this type of care provision with nurse practitioners as the designated principal home care providers in a family medicine program in a large Canadian urban setting.
Patients requiring hospitalization to the family medicine service ward, for any diagnosis, who met selection criteria, were invited to enter the hospital in the home program as an alternative to admission. Participants in the hospital in the home program, their caregivers, and the physicians responsible for their care were surveyed about their perceptions of the program. Nurse practitioners, who provided care, were surveyed and interviewed.
Ten percent (104) of admissions to the ward were screened, and 37 patients participated in 44 home hospital admissions. Twenty nine patient, 17 caregiver and 38 provider surveys were completed. Most patients (88%–100%) and caregivers (92%–100%) reported high satisfaction levels with various aspects of health service delivery. However, a significant proportion in both groups stated that they would select to be treated in-hospital should the need arise again. This was usually due to fears about the safety of the program. Physicians (98%–100%) and nurse practitioners also rated the program highly. The program had virtually no negative impact on the physician workload. However nurse practitioners felt that the program did not utilize their full expertise.
Provision of hospital level care in the home is well received by patients, their caregivers and health care providers. As a new program, investment in patient education about program safety may be necessary to ensure its long term success. A small proportion of hospital admissions were screened for this program. Appropriate dissemination of program information to family physicians should help buy-in and participation. Nurse practitioners' skills may not be optimally utilized in this setting.
PMCID: PMC2020484  PMID: 17705866
17.  Promoting best practices for control of respiratory infections 
Canadian Family Physician  2006;52(9):1110.
To determine the effectiveness of a short-term intervention to promote best practices for control of respiratory infections in primary care physicians’ offices.
Before-after observational study.
Family physicians’ offices in Ottawa, Ont.
General practitioners and office staff.
Four infection-control practices (use of masks, alcohol-based hand gel, and signs, and asking patients to sit at least 1 m apart in the waiting room) were observed, and 2 reported infection-control practices (disinfecting surfaces and use of hand-gel dispensers in examining rooms) were audited before the intervention and 6 weeks after the intervention.
Percentage of patients asked to use masks and alcohol-based hand gel, number of relevant signs, and percentage of patients asked to sit at least 1 m away from other patients. Percentage of surfaces disinfected and percentage of physicians using hand-gel dispensers in examining rooms.
Of 242 practices invited, 53 agreed to participate (22% response rate), and within those practices, 143/151 (95%) physicians participated. Signs regarding respiratory infection control measures increased from 15.4% to 81.1% following the intervention (P < .001). At least 1 patient with cough and fever was given a mask in 17% of practices before the intervention; during the observation period after the intervention, at least 1 patient was given a mask in 66.7% of practices (P < .001). Patients were instructed to use alcohol-based hand gel in 24.5% of practices before the intervention and in 79.2% of practices after it (P < .001). Instruction to sit at least 1 m from others in the waiting area was given in 39.6% of practices before the intervention and in 52.8% of practices following the intervention (P < .001). Before the intervention, the percentage of practices using all 4 audited primary prevention measures was 3.8%; after the intervention, 52.8% of practices were using them (P < .001), demonstrating a 49% increase in adoption of best practices.
A multifaceted intervention by public health nurses successfully promoted best practices for control of respiratory infections in primary care offices. Collaboration between public health services and primary care can promote best practices and warrants further study and development in areas of common interest.
PMCID: PMC1783740  PMID: 17279223
18.  Multiple Combination Bactericidal Testing of Staphylococcal Biofilms from Implant-Associated Infections 
Standardized susceptibility testing fails to predict in vivo resistance of device-related infections to antimicrobials. We assessed agents and combinations of antimicrobials against clinical isolates of Staphylococcus epidermidis and S. aureus (methicillin-resistant S. aureus and methicillin-sensitive S. aureus) retrieved from device-associated infections. Isolates were grown planktonically and as biofilms. Biofilm cultures of the organisms were found to be much more resistant to inhibitory and bactericidal effects of single and combination antibiotics than planktonic cultures (P < 0.001). Rifampin was the most common constituent of antibiotic combinations active against staphylococcal biofilms. Other frequently effective antimicrobials were vancomycin and fusidic acid. Susceptibility testing involving biofilm-associated bacteria suggests new options for combination antibiotic therapy.
PMCID: PMC1346774  PMID: 16377667
19.  Single and Combination Antibiotic Susceptibilities of Planktonic, Adherent, and Biofilm-Grown Pseudomonas aeruginosa Isolates Cultured from Sputa of Adults with Cystic Fibrosis 
Journal of Clinical Microbiology  2002;40(11):4172-4179.
Evidence suggests that Pseudomonas aeruginosa bacteria form biofilms within the airways of adults with cystic fibrosis (CF). The objective of this study was to determine whether clinical isolates of P. aeruginosa recovered from adults with CF have similar susceptibilities to individual antibiotics and to antibiotic combinations when grown as adherent monolayers or as biofilms compared to when they are grown using planktonic methods. Twelve multiresistant P. aeruginosa isolates, one mucoid and one nonmucoid from each of six CF patients, were grown conventionally under planktonic conditions, as adherent bacterial monolayers, and as biofilms. Each bacterial isolate remained genotypically identical despite being cultured under planktonic, adherent, or biofilm growth conditions. Isolates grown as adherent monolayers and as biofilms were less susceptible to bactericidal killing by individual antibiotics compared to those grown planktonically. More importantly, biofilm-grown bacteria, but not adherent monolayer-grown bacteria, were significantly less susceptible to two- and three-drug combinations of antibiotics than were planktonically grown bacteria (P = 0.005). We conclude that biofilm-grown bacteria derived from patients with CF show decreased susceptibility to the bactericidal effects of antibiotic combinations than do adherent and planktonically grown bacteria.
PMCID: PMC139693  PMID: 12409393
21.  Prospective, randomized comparison of intravenous and oral ciprofloxacin with intravenous ceftazidime in the treatment of nosocomial pneumonia 
To compare the efficacy of intravenous and oral ciprofloxacin and intravenous ceftazidime in the treatment of nosocomial pneumonia.
Randomized, nonblinded, multicentre comparative trial.
Seven Canadian university hospitals.
Adult patients with moderate to severe pneumonia developing 72 h or longer after hospitalization.
After informed consent was obtained, patients were randomized to receive intravenous ciprofloxacin 300 mg every 12 h or ceftazidime 2 g every 8 h. After three days, patients in the ciprofloxacin arm could be switched to oral ciprofloxacin, 750 mg every 12 h. Concomitant clindamycin was allowed for three days in patients with syndromes consistent with Gram-positive or anaerobic infection. Erythromycin could be used if cultures revealed no pathogen.
A total of 149 patients were enrolled, of whom 124 were eligible for efficacy analysis. Of 119 pathogens identified in 87 patients, 84 were Gram-negative, and 35 Gram-positive. The mean duration of ciprofloxacin therapy was 12.1 days, of which 9.2 days were given intravenously. Ceftazidime was given for a mean of 9.8 days. There was eradication or reduction of pathogens in 75.7% of ciprofloxacin patients and 70.6% of the ceftazidime group. Clinical resolution or improvement occurred in 87.1% of ciprofloxacin recipients and 87.3% of the ceftazidime group. Eight ciprofloxacin and six ceftazidime patients died. Overall outcomes were considered to be successful in 85.2% of ciprofloxacin patients and 87.1% of ceftazidime recipients. Adverse events were mild.
There were similar efficacy and safety of intravenous and oral ciprofloxacin and intravenous ceftazidime in the treatment of patients with hospital-acquired pneumonia. Physicians were reluctant to use oral therapy in patients.
PMCID: PMC3327348  PMID: 22514482
Cephalosporins; Fluoroquinolones; Nosocomial infection; Pneumonia
22.  Q-fever endocarditis 
Canadian Medical Association Journal  1985;133(12):1228-1230.
PMCID: PMC1346577  PMID: 4063935

Results 1-22 (22)