Acquisition of Pseudomonas cepacia at summer camps for patients with cystic fibrosis. Summer Camp Study Group

Evaluating the Feasibility of a Multiplayer Role-Playing Game as a Behavioral Health Intervention in Adolescent Patients With Chronic Physical or Mental Conditions: Protocol for a Cohort Study

BACKGROUND

Numerous studies have revealed that adolescents with chronic physical or mental conditions (CPMCs) are at an increased risk for depression and anxiety, with serious direct and indirect negative effects on treatment adherence, family functioning, and health-related quality of life. As game-based approaches are effective interventions in treating anxiety and depression, we propose to explore the use of a multiplayer role-playing game (RPG) as a potential intervention for social isolation, anxiety, and depression.

OBJECTIVE

The objectives of this study were to (1) determine the feasibility of using Masks, a multiplayer RPG, as an intervention for social isolation, anxiety, and depression in adolescents with CPMCs; (2) evaluate the viability of the research process; and (3) gauge participation in and engagement with RPG-based interventions.

METHODS

This study is a remote synchronous game-based intervention for adolescents with CPMCs aged 14-19 years. Eligible participants completed a web-based baseline survey to assess anxiety, depression, and social isolation and to identify their gaming habits. After completing the baseline survey, they participated in 5 moderated Masks game sessions. In Masks, players assume the roles of young superheroes; select their character types, superpowers; and perform actions determined by the game's rule system and dice rolls. All game sessions were played using Discord, a communication platform commonly used by gaming communities. Games were led and moderated by game masters (GMs). After each game session, participants completed surveys to assess changes in anxiety, depression, and social isolation, and their attitude toward the game and the user experience. The participants also completed an exit survey after all 5 game sessions (modified version of the Patient Health Questionnaire and the Generalized Anxiety Disorder Questionnaire, and 17 open-ended questions). The GMs rated each game session and reported on gameplay, player behavior, comfort, and engagement levels of the players.

RESULTS

As of March 2020, six participants were recruited for the pilot study to participate in moderated web-based game sessions of Masks; 3 completed all game sessions and all required assessments. Although the number of participants was too low to draw generalizable conclusions, self-reported clinical outcomes did seem to indicate a positive change in depression, anxiety, and social isolation symptoms. Qualitative analysis of postgame survey data from participants and GMs indicated high levels of engagement and enjoyment. Furthermore, the participants provided feedback about improved mood and engagement related to weekly participation in Masks. Lastly, responses to the exit survey showed interest in future RPG-related studies.

CONCLUSIONS

We established a workflow for gameplay and evaluated a research protocol for evaluating the impact of RPG participation on isolation, anxiety, and depression symptoms in adolescents with CPMCs. Preliminary data collected from the pilot study support the validity of the research protocol and the use of RPG-based interventions in larger clinical studies.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR1-10.2196/43987.

The Impact of Resistant Bacterial Pathogens including Pseudomonas aeruginosa and Burkholderia on Lung Transplant Outcomes

Pseudomonas and Burkholderia are gram-negative organisms that achieve colonization within the lungs of patients with cystic fibrosis, and are associated with accelerated pulmonary function decline. Multidrug resistance is a hallmark of these organisms, which makes eradication efforts difficult. Furthermore, the literature has outlined increased morbidity and mortality for lung transplant (LTx) recipients infected with these bacterial genera. Indeed, many treatment centers have considered Burkholderia cepacia infection an absolute contraindication to LTx. Ongoing research has delineated different species within the B. cepacia complex (BCC), with significantly varied morbidity and survival profiles. This review considers the current evidence for LTx outcomes between the different subspecies encompassed within these genera as well as prophylactic and management options. The availability of meta-genomic tools will make differentiation between species within these groups easier in the future, and will allow more evidence-based decisions to be made regarding suitability of candidates colonized with these resistant bacteria for LTx. This review suggests that based on the current evidence, not all species of BCC should be considered contraindications to LTx, going forward.

Environmental Microbial Contamination during Cystic Fibrosis Group-Based Psychotherapy

Living with cystic fibrosis (CF) exposes patients to the risk of developing anxiety and depression, with therapeutic compliance reduction, hospitalization increase, and quality of life and health outcomes deterioration. As pulmonary infections represent the major cause of morbidity and mortality in patients with CF, environmental contamination due to droplet dispersion and the potential transmission from environment to such patients should be prevented. Therefore, in-person contact, including group-based psychotherapy, are strongly discouraged. Nevertheless, group sharing of disease-related experiences represents a way to recover the inner resources essential for dealing with a chronic pathology. Keeping in mind the guidelines for infection control, the aim of this study is to evaluate the risk of the dissemination of microorganisms in a restricted environment where patients with CF attend group psychotherapy sessions. Five patients, selected according to their microbiological status, attended 32 group-based psychological/psychoanalytic meetings. Before each session, they were asked to observe the infection control recommendations. Microbiological environmental monitoring (MEM) has been performed to evaluate both air and surface contamination. As reported, a strict observation of standard precautions allows one to avoid environmental contamination by pathogens of the CF respiratory tract. Although infection control guidelines discourage group-based psychological/psychoanalytic interventions, our observations report the feasibility and safety of group psychotherapy when strict precautions are taken.

Epidemiology, Biology, and Impact of Clonal Pseudomonas aeruginosa Infections in Cystic Fibrosis

Chronic lower airway infection with Pseudomonas aeruginosa is a major contributor to morbidity and mortality in individuals suffering from the genetic disease cystic fibrosis (CF). Whereas it was long presumed that each patient independently acquired unique strains of P. aeruginosa present in their living environment, multiple studies have since demonstrated that shared strains of P. aeruginosa exist among individuals with CF. Many of these shared strains, often referred to as clonal or epidemic strains, can be transmitted from one CF individual to another, potentially reaching epidemic status. Numerous epidemic P. aeruginosa strains have been described from different parts of the world and are often associated with an antibiotic-resistant phenotype. Importantly, infection with these strains often portends a worse prognosis than for infection with nonclonal strains, including an increased pulmonary exacerbation rate, exaggerated lung function decline, and progression to end-stage lung disease. This review describes the global epidemiology of clonal P. aeruginosa strains in CF and summarizes the current literature regarding the underlying biology and clinical impact of globally important CF clones. Mechanisms associated with patient-to-patient transmission are discussed, and best-evidence practices to prevent infections are highlighted. Preventing new infections with epidemic P. aeruginosa strains is of paramount importance in mitigating CF disease progression.

Risk of Bacterial Transmission in Bronchiectasis Outpatient Clinics

Purpose of Review

The purpose of this review is to discuss the risk of bacterial cross-infection for bronchiectasis patients in the outpatient setting. Cross-infection has primarily been a matter of concern in cystic fibrosis (CF). There is considerable evidence of transmission of pathogens between CF patients, and this has led to guideline recommendations advocating strict segregation policies. Guidelines in bronchiectasis do not specifically address the issue of cross-infection. If cross-infection is prevalent, it may have significant implications for patients and the practical running of specialist care.

Recent Findings

Multiple UK-based studies have now published evidence of cross-infection with Pseudomonas aeruginosa within cohorts of bronchiectasis patients; however, the risk does not appear to be high. There is also evidence suggesting cross-infection from CF patients to bronchiectasis patients.

Summary

The current evidence for cross-infection in bronchiectasis is limited, but suggests a small risk with Pseudomonas aeruginosa. Longitudinal studies looking at Pseudomonas aeruginosa and other pathogens are now required.

Isolation of Infectious Cystic Fibrosis Patients: Results of a Systematic Review

Objective:

Respiratory tract infections significantly contribute to morbidity and mortality among cystic fibrosis (CF) patients. Therefore, pathogen transmission needs to be prevented. There are several guidelines for the care of CF patients, but no transparent systematic literature review has been published.

Methods:

We conducted a systematic literature review (January 1966 to September 2004) dealing with segregation of CF patients colonized withBurkholderia cepaciaspecies,Pandoraeaspecies,Pseudomonas aeruginosa, Stenotrophomonas maltophilia,orAlcaligenesspecies. Quality of studies was evaluated by taking patient population size, existence of control-patients, patient randomization, diagnostic approach, and bacteria typing methods into account.

Results:

One hundred ninety-nine studies were found. Evidence and quality of 102 publications were evaluated. In 99 publications, recommendations concerning segregation measures for infectious CF patients were determined including a total of 11,576 patients. No randomized, controlled trials had been conducted. Fifty of 56 authors strongly recommended isolation of CF patients infected withB. cepaciaorPandoraeaspecies. In 31 of 39 studies, interpatient spread ofPseudomonas aeruginosawas documented or had been brought to an end by isolation of patients. Only five studies had addressed S.maltophiliaorAlcaligenesspecies.

Conclusions:

Patients colonized withB. cepaciaorPandoraeaspecies are to be separated from noncolonized patients in single rooms. Patients harboring multidrug-resistantPseudomonas aeruginosa, S. maltophilia,orAlcaligenesspecies may not share a room with immunocompromised patients, in intensive care units, or with other CF patients anywhere in the hospital.

Infection Prevention and Control Guideline for Cystic Fibrosis: 2013 Update

The 2013 Infection Prevention and Control (IP&C) Guideline for Cystic Fibrosis (CF) was commissioned by the CF Foundation as an update of the 2003 Infection Control Guideline for CF. During the past decade, new knowledge and new challenges provided the following rationale to develop updated IP&C strategies for this unique population:

1.The need to integrate relevant recommendations from evidence-based guidelines published since 2003 into IP&C practices for CF. These included guidelines from the Centers for Disease Control and Prevention (CDC)/Healthcare Infection Control Practices Advisory Committee (HICPAC), the World Health Organization (WHO), and key professional societies, including the Infectious Diseases Society of America (IDSA) and the Society for Healthcare Epidemiology of America (SHEA). During the past decade, new evidence has led to a renewed emphasis on source containment of potential pathogens and the role played by the contaminated healthcare environment in the transmission of infectious agents. Furthermore, an increased understanding of the importance of the application of implementation science, monitoring adherence, and feedback principles has been shown to increase the effectiveness of IP&C guideline recommendations.

2.Experience with emerging pathogens in the non-CF population has expanded our understanding of droplet transmission of respiratory pathogens and can inform IP&C strategies for CF. These pathogens include severe acute respiratory syndrome coronavirus and the 2009 influenza A H1N1. Lessons learned about preventing transmission of methicillin-resistantStaphylococcus aureus(MRSA) and multidrug-resistant gram-negative pathogens in non-CF patient populations also can inform IP&C strategies for CF.

Improved patient safety through reduced airway infection rates in a paediatric cystic fibrosis programme after a quality improvement effort to enhance infection prevention and control measures

OBJECTIVE

To reduce the risk of pathogen transmission between patients with cystic fibrosis (CF) and decrease the rate of acquisition of new CF pathogens in our patients.

DESIGN

Using the Model for Improvement, we developed a new process for infection prevention and control in our outpatient CF clinics.

SETTING

Paediatric CF programme at Ann & Robert H. Lurie Children's Hospital of Chicago; approximately 180 paediatric patients aged birth to 21 years.

PARTICIPANTS

All paediatric patients enrolled in the Cystic Fibrosis Foundation Patient Data Registry at this institution.

INTERVENTIONS

Implemented contact precautions with all patients, regardless of respiratory tract culture results.

MEASUREMENT

Respiratory tract culture rates of specific pathogens by quarter were compared prior to and after implementation.

RESULTS

Our percentage of patients with a positive respiratory tract culture for Pseudomonas aeruginosa dropped from 30% to 21% (p<0.0001) and for methicillin-resistant Staphylococcus aureus (MRSA) dropped from 10.8% to 8.7% (p=0.008).

CONCLUSIONS

Use of contact precautions by all care providers, for all patients, regardless of respiratory tract culture results resulted in decreased P aeruginosa and MRSA infection rates.

Burkholderia cepacia complex Phage-Antibiotic Synergy (PAS): antibiotics stimulate lytic phage activity

The Burkholderia cepacia complex (Bcc) is a group of at least 18 species of Gram-negative opportunistic pathogens that can cause chronic lung infection in cystic fibrosis (CF) patients. Bcc organisms possess high levels of innate antimicrobial resistance, and alternative therapeutic strategies are urgently needed. One proposed alternative treatment is phage therapy, the therapeutic application of bacterial viruses (or bacteriophages). Recently, some phages have been observed to form larger plaques in the presence of sublethal concentrations of certain antibiotics; this effect has been termed phage-antibiotic synergy (PAS). Those reports suggest that some antibiotics stimulate increased production of phages under certain conditions. The aim of this study is to examine PAS in phages that infect Burkholderia cenocepacia strains C6433 and K56-2. Bcc phages KS12 and KS14 were tested for PAS, using 6 antibiotics representing 4 different drug classes. Of the antibiotics tested, the most pronounced effects were observed for meropenem, ciprofloxacin, and tetracycline. When grown with subinhibitory concentrations of these three antibiotics, cells developed a chain-like arrangement, an elongated morphology, and a clustered arrangement, respectively. When treated with progressively higher antibiotic concentrations, both the sizes of plaques and phage titers increased, up to a maximum. B. cenocepacia K56-2-infected Galleria mellonella larvae treated with phage KS12 and low-dose meropenem demonstrated increased survival over controls treated with KS12 or antibiotic alone. These results suggest that antibiotics can be combined with phages to stimulate increased phage production and/or activity and thus improve the efficacy of bacterial killing.

Cystic fibrosis: myths. mistakes, and dogma

As a student I recall being told that half of what we would learn in medical school would be proven to be wrong. The challenges were to identify the incorrect half and, often more challenging, be willing to give up our entrenched ideas. Myths have been defined as traditional concepts or practice with no basis in fact. A misunderstanding is a mistaken approach or incomplete knowledge that can be resolved with better evidence, while firmly established misunderstandings can become dogma; a point of view put forth as authoritative without basis in fact. In this paper, I explore a number of myths, mistakes, and dogma related to cystic fibrosis disease and care. Many of these are myths that have long been vanquished and even forgotten, while others are controversial. In the future, many things taken as either fact or "clinical experience" today will be proven wrong. Let us examine these myths with an open mind and willingness to change our beliefs when justified.

Halting the spread of epidemic pseudomonas aeruginosa in an adult cystic fibrosis centre: a prospective cohort study

Objectives

To assess if cohort segregation policies are effective in preventing cross-infection in cystic fibrosis (CF) clinics.

Design

A prospective cohort study.

Setting

A large adult CF centre in Northwest England.

Participants

All CF patients cared for at the Liverpool adult CF centre 2003–2009.

Methods

Regular sputum sampling with genotyping of pseudomonas aeruginosa (Psa) isolates led to a policy of inpatient and outpatient segregation by microbiological group.

Main outcome measures

Prevalence and cross-infection/super-infection rates of a transmissible Psa strain, i.e. the Liverpool epidemic strain (LES) in adult CF patients at the Liverpool adult CF centre from 2003 to 2009.

Results

There was a decline in the proportion of patients with LES (71–53%) and an increase in those with unique strains (23–31%) and without Psa infection (6–17%) from 2003 to 2009. There were two cases of LES super-infection and one case of new chronic Psa infection (with a unique strain). There were no cases of transmissible strain infection in patients previously uninfected by Psa.

Conclusions

Our segregation policy has halted the spread of the commonest highly transmissible strain in the UK (LES) in our clinic, without endangering patients who were not previously infected with Psa. It confirms that if genotypic surveillance is used, it is unnecessary to segregate patients infected with unique strains from those without Psa infection.

Transmissibility and infection control implications of Burkholderia cepacia in cystic fibrosis

OBJECTIVE

To describe the microbiology and potential virulence factors of Burkholderia cepacia; to discuss the studies that have investigated its mode of transmission among cystic fibrosis patients; and to identify the major risk factors associated with acquisition of this pathogen inside and outside of the hospital environment.

DATA SOURCES

MEDLINE search of the literature published between 1986 and 1997 using the key words/subject words Pseudomonas cepacia, Burkholderia cepacia, cystic fibrosis, infection control and transmissibility, and the bibliography of selected papers.

DATA EXTRACTION

Selected studies examining epidemiology, microbiology, virulence factors and mode of transmission of B cepacia in cystic fibrosis.

DATA SYNTHESIS AND CONCLUSIONS

B cepacia is a multidrug-resistant Gram-negative bacillus that has recently been recognized as a major respiratory pathogen in patients with cystic fibrosis. Colonization by this organism can lead to rapid pulmonary deterioration and premature death. Recent studies based on genomic subtyping techniques have suggested that it can be transmitted from person to person. Close social contact and hospitalization have been identified as risk factors for cross-infection. With the implementation of strict infection control policies such as segregation according to colonization status, the rate of new colonization has substantially decreased in most cystic fibrosis treatment centres.

Travelling with cystic fibrosis: recommendations for patients and care team members

There are no European Guidelines on issues specifically related to travel for people with cystic fibrosis (CF). The contributors to these recommendations included 30 members of the ECORN-CF project. The document is endorsed by the European Cystic Fibrosis Society and sponsored by the Executive Agency of Health and Consumers of the European Union and the Christiane Herzog Foundation. The main goal of this paper is to provide patient-oriented advice that complements medical aspects by offering practical suggestions for all aspects involved in planning and taking a trip. The report consists of three main sections, preparation for travel, important considerations during travel and at the destination, and issues specific to immunocompromised travellers. People with CF should be encouraged to consult with their CF centre prior to travel to another country. The CF centre can advise on the necessary preparation for travel, the need for vaccinations, essential medications that should be brought on the trip and also provide information relating to CF care in the region and plan of action in case of an emergency.

Rehabilitation Programs for Cystic Fibrosis - View from a CF Center

Background:

Rehabilitation programs are comprehensive interventions which effectively improve the health status and reduce costs in chronic respiratory illnesses. Because patients with cystic fibrosis have been discouraged to participate for concerns of microbial cross infection, the efficacy of systematic rehabilitation is unknown for this group.

Methods:

We retrospectively studied 142 cystic fibrosis patients aged 2-46 years who participated in rehabilitation programs taking place in Germany/Switzerland and in Israel, focusing on changes in lung function and weight.

Results:

During 172 stays in 97 patients in Israel and 68 stays in 45 patients rehabilitating in Germany/Switzerland, overall lung function and weight improved. Outcome did not differ between Israel and German/Swiss sites. Interestingly, lung function improved during the initial phase of the stay, whereas weight gain was sustained throughout. The study uncovered gaps in reporting sufficient individual outcome information back to the admitting centre.

Conclusions:

Rehabilitation programs specified for cystic fibrosis patients need to be assessed prospectively to optimize treatment of this life limiting condition.

Infection control in cystic fibrosis: cohorting, cross-contamination, and the respiratory therapist

Cystic fibrosis (CF) is a complex genetic disease characterized by lung infections that lead to early morbidity and death. Pathogens that commonly infect the lungs of patients with CF include Staphylococcus aureus, Haemophilus influenzae, Pseudomonas aeruginosa, and Burkholderia cepacia. Aggressively treating pulmonary infection with antibiotics has contributed to improved survival in patients with CF but has also promoted multiple-drug-resistant bacteria. Other complexities include the ability of bacteria to form biofilms, which makes them more resistant to antibiotics, and emerging pathogens in CF, of which the clinical importance is not yet clear. Increasing evidence of patient-to-patient transmission of CF pathogens led the Cystic Fibrosis Foundation to produce evidence-based infection-control recommendations, which stress 4 principles: standard precautions, transmission-based precautions, hand hygiene, and care of respiratory equipment. Respiratory therapists need to know and follow these infection-control recommendations. Cohorting patients infected with B. cepacia complex is one of several interventions successful at keeping the spread of this pathogen low, but cohorting patients who are infected/colonized with other microbes is controversial, the main argument of which is not being certain of a patient's present respiratory culture status at any given patient visit.

Patient risk of contact with respiratory pathogens from inanimate surfaces in a cystic fibrosis outpatient clinic. A prospective study over a four-year period

Acquisition of respiratory pathogens such as Pseudomonas aeruginosa (PA) is associated with increased morbidity and mortality in cystic fibrosis (CF). Research on the prevalence of these pathogens on environmental surfaces of a CF Center is scanty, and so far no study has determined what risk CF patients have of coming in contact with them during their visits to the CF Center. This study is aimed at assessing the prevalence of some respiratory pathogens in samples taken systematically during a 4-year period from inanimate surfaces and sinks in a CF Outpatient Clinic, and to estimate the risk that a non-PA colonized CF patient has of contact with PA when visiting the CF Center. Microbiological samples were taken and cultured from the inanimate surfaces and sinks of the Outpatient clinic of a CF Center once a month from 2001 to 2005. Four hundred and sixty environmental specimens were collected: 36.3% were positive for respiratory pathogens (23% of rooms' inert surfaces, 49.5% of sinks). Achromobacter xylosoxidans was found in 0.8% of surface samples. PA was isolated in 22.8% samples. The estimated risk for each non-colonized patient of coming in contact with PA on the surfaces in the Clinic at each visit was 5.4 per thousand (CI95% 0.9-30.1). Genotyping of a sample of environmental PA strains revealed a genetic relation between environmental and clinical isolates in most cases. Micro-organisms relevant for CF patients can be found on inanimate surfaces of a CF Center, although the risk for patients of coming in contact with PA during their visits to the CF center seems low.

Infection Control Practice in Cystic Fibrosis Centers

In this article, the authors outline some of the major historical events that signaled the need to better understand mechanisms of infection in cystic fibrosis (CF). The authors discuss general principles of infection control, focusing on issues of particular importance to patients who have CF. The authors also describe the major pathogens associated with the CF airway, provide a review of findings from inpatient and outpatient studies of infection control, and provide an outline of future directions for investigation.

Multidrug-resistant organisms in cystic fibrosis: management and infection-control issues

Chronic infection and inflammation are the hallmarks of cystic fibrosis lung disease. As cystic fibrosis patients are living longer owing to more intense treatment, multidrug-resistant organisms are being isolated increasingly from patients' respiratory tracts. While the adverse effects of Pseudomonas aeruginosa and Burkholderia cepacia complex are well described, less is known about the clinical significance of other emerging multidrug-resistant organisms, such as methicillin-resistant Staphylococcus aureus and Stenotrophomonas maltophilia. Owing to multiple mechanisms of antimicrobial resistance, these organisms are difficult to treat and often require combination antibiotic therapy. Until more is known about their pathogenicity and effect on clinical outcomes, physicians should be aware of the potential transmissibility of these organisms and implement adequate infection control strategies.

Mucoviscidose : le kinésithérapeute face au risque infectieux

INTRODUCTION

Respiratory infections play a deleterious role in the progression of patients suffering from cystic fibrosis. Cross infections and epidemics have been documented in these patients, justifying a rigorous prevention regime.

BACKGROUND

This prevention regime concerns all health workers and rests on various recommendations. Segregation of patients and hand hygiene are important factors. Respiratory equipment and, more specifically, nebulisers represent a potential source of bacterial contamination requiring special attention. In the same perspective the risks related to the health care environment, particularly the lung function laboratory, should not be ignored. The modalities of prevention sometimes have a significant psychological impact that may often be reduced by careful explanation.

CONCLUSIONS

In view of the time spent in contact with these patients the physiotherapists are naturally involved in this prevention regime which is an integral part of their treatment.

Isolation measures for prevention of infection with respiratory pathogens in cystic fibrosis: a systematic review

Respiratory infections are the most important cause of morbidity and mortality in patients with cystic fibrosis (CF). These infections are typically caused by a limited number of respiratory pathogens, particularly Burkholderia cepacia complex (BCC) and Pseudomonas aeruginosa (PA). Since the 1980s, several outbreaks of unique strains of PA and BCC among CF patients attending the same CF care centres have been described, leading to a sharp decline in the patients' health. One of the measures adopted in CF centres to interrupt ongoing outbreaks is the separation of patients with a respiratory tract culture that is positive for PA or BCC from patients who are not infected. This type of measure has been implemented routinely in many CF centres to prevent cross-transmission of PA and BCC. The aim of this review was to determine what evidence is available to support the efficacy of isolation (or segregation) practices in preventing, delaying or reducing the risk for CF patients of acquiring PA and BCC. A systematic review of scientific literature from 1980 to 31 December 2004 was performed. Existing guidelines regarding infection control in CF were also analysed. In total, 398 relevant papers were retrieved. Only 10 well-designed studies were found that evaluated the efficacy of isolation practices in preventing the transmission of respiratory pathogens in CF care centres (one prospective controlled study, one retrospective cohort study, five 'before-after' studies and three cross-sectional studies. No systematic reviews or randomized controlled trials exist on this subject. In the absence of studies with an experimental, controlled design, the efficacy of isolation practices in preventing the transmission of respiratory pathogens in CF remains unproven. However, notwithstanding the considerable limits represented by the study designs, which were mainly retrospective, the observational studies reviewed seem to support the implementation of isolation (or segregation) measures to reduce the risk of transmission of BCC and PA in CF patients.

Impact ofBurkholderia dolosaon Lung Function and Survival in Cystic Fibrosis

RATIONALE

Chronic infection with Burkholderia cepacia complex bacteria in cystic fibrosis is associated with accelerated decline in pulmonary function and increased mortality. Clinical implications of the recently characterized genomovar VI, B. dolosa, are unknown.

OBJECTIVES

Characterization of impact of B. dolosa on pulmonary function and mortality in cystic fibrosis.

METHODS

We compared patients chronically infected with B. dolosa (n = 31) with unmatched patients with B. multivorans (n = 24) and with age- and sex-matched control subjects without Burkholderia species (n = 58). We analyzed rates of pulmonary function decline (% predicted FEV(1)) using a random effects model assuming segmented linear trends. All available FEV(1) measurements from 5 yr (median, 4.8) before until 2.5 yr (median, 1.5) after the first positive culture for Burkholderia (reference date) were analyzed. Survival was compared using the Kaplan-Meier method and proportional hazards model.

MEASUREMENTS AND MAIN RESULTS

Baseline FEV(1) and rate of decline were similar in the cohorts. Decline in FEV(1) after the reference date accelerated in patients with B. dolosa (-2.3 percentage points/yr pre vs. -7.1 post, p = 0.002), but was unchanged in the B. multivorans and control patients (-2.3 vs. -0.8 post, p = 0.38, and -2.1 pre vs. -0.5 post, p = 0.20, respectively). The probability of dying within 18 mo of the reference date was 13, 7, and 3% for B. dolosa, B. multivorans, and control patients, respectively (B. dolosa vs. control hazard ratio, 10.8; 95% confidence interval, 1.3-92.8; p = 0.03).

CONCLUSIONS

B. dolosa chronic infection in cystic fibrosis is associated with accelerated loss of lung function and decreased survival.

Transmission of Burkholderia cepacia complex: evidence for new epidemic clones infecting cystic fibrosis patients in Italy

To analyze national prevalence, genomovar distribution, and epidemiology of the Burkholderia cepacia complex in Italy, 225 putative B. cepacia complex isolates were obtained from 225 cystic fibrosis (CF) patients attending 18 CF centers. The genomovar status of these isolates was determined by a polyphasic approach, which included whole-cell protein electrophoresis and recA restriction fragment length polymorphism (RFLP) analysis. Two approaches were used to genotype B. cepacia complex isolates: BOX-PCR fingerprinting and pulsed-field gel electrophoresis (PFGE) of genomic macrorestriction fragments. A total of 208 (92%) of 225 isolates belonged to the B. cepacia complex, with Burkholderia cenocepacia as the most prevalent species (61.1%). Clones delineated by PFGE were predominantly linked to a single center; in contrast, BOX-PCR clones were composed of isolates collected either from the same center or from different CF centers and comprised multiple PFGE clusters. Three BOX-PCR clones appeared of special interest. One clone was composed of 17 B. cenocepacia isolates belonging to recA RFLP type H. These isolates were collected from six centers and represented three PFGE clusters. The presence of insertion sequence IS 1363 in all isolates and the comparison with PHDC reference isolates identified this clone as PHDC, an epidemic clone prominent in North American CF patients. The second clone included 22 isolates from eight centers and belonged to recA RFLP type AT. The genomovar status of strains with the latter RFLP type is not known. Most of these isolates belonged to four different PFGE clusters. Finally, a third clone comprised nine B. pyrrocinia isolates belonging to recA RFLP type Se 13. They represented three PFGE clusters and were collected in three CF centers.

Cystic fibrosis since 1938

Cystic fibrosis (CF) was distinguished from celiac disease in 1938. Then, it was a pathologic diagnosis, life expectancy was approximately 6 months, and the autosomal recessive disease was believed to arise from abnormal mucus plugging exocrine ducts. Death often occurred from lung infection. Discovery of the sweat electrolyte defect in 1953 and standardization of the sweat test in 1959 allowed identification of milder cases, and CF was no longer considered only a disorder of mucus. In 1955, establishment of centers with programs of aggressive, comprehensive care initiated striking improvement in longevity. The pillars of care established then (attention to nutrition, airway clearance, treatment of lung infection) remain today. In 1983, chloride transport was identified as the basic physiologic CF defect, accompanied by increased sodium reabsorption. In 1980, we learned that inflammation contributes independently to lung disease and constitutes an independent therapeutic target. In 1989, the discovery of the CF gene demonstrated the basic defect to be in a cAMP-regulated chloride channel. This afforded new diagnostic tests, opportunities for research, and prospects for using the gene as therapy. Since then, substantial advances in basic and clinical research catalyzed therapeutic improvements: median survival age now exceeds 30 years. The Cystic Fibrosis Foundation center network provides not only opportunity to conduct clinical trials but also means to disseminate new therapies. In the future, treatments directed at the basic defect can be expected, with concomitant improvements in morbidity and mortality.

[Epidemiology of nosocomial infections due to Pseudomonas aeruginosa, Burkholderia cepacia and Stenotrophomonas maltophilia]

Non-fermentative Gram negative rods are opportunistic pathogens responsible for nosocomial infections. Using phenotypic markers (serotypes for Pseudomonas aeruginosa and antibiotic susceptibility) allows a preliminary screening of epidemiologically-related strains. However, genotypic markers are necessary to better characterize nosocomial strains for the investigation of outbreaks or cross-transmissions in the hospital setting. Infections due to P. aeruginosa, Burkholderia. cepacia or Stenotrophomonas. maltophilia are usually hospital-acquired and responsible for a high mortality rate as illustrated by the lethality of nosocomial pneumonia due to P. aeruginosa. The severity of these infections is due to the virulence factors of the bacteria and to their occurrence in debilitated patients in whom invasives devices are used. The hospital environment can act as a reservoir with a rate of exogeneous transmission of these bacteria as high as 50% in some studies. To better prevent nosocomial infections related to Gram negative non fermentative rods, the control of the aqueous hospital environment, the strict application of hand disinfection and the investigation of potential cross-transmission in the hospital setting are needed.

Widespread clone of Burkholderia cenocepacia in cystic fibrosis patients in the Czech Republic

The morbidity and mortality rates in patients with cystic fibrosis (CF) are significantly affected by infections with Burkholderia cepacia complex. In a Czech CF Centre, the prevalence of the infection reached up to 30 %, with the majority of patients found to be infected with Burkholderia cenocepacia (formerly genomovar III of the Burkholderia cepacia complex). Since B. cenocepacia is associated with patient-to-patient transmission and epidemic outbreaks among CF patients, this study sought to examine the epidemiological relatedness between the Czech isolates belonging to the genomovar-homogeneous group. Eighty-three clinical isolates recovered from 67 CF patients were analysed using a random amplified polymorphic DNA (RAPD) assay and macrorestriction typing (SpeI and XbaI) followed by PFGE. A single predominant banding pattern shared by multiple isolates was detected, although SpeI-generated PFGE results yielded a higher rate of inter-pattern variability in comparison to the more uniform RAPD and XbaI-generated PFGE results for this clone. Both typing systems also showed that only three out of 67 patients harboured strains distinct from the major strain type. The dominant clone was characterized by PCR positivity for the B. cepacia epidemic strain marker, PCR negativity for the cable pilin subunit gene and close genetic relatedness to the epidemic strain of RAPD 01 type previously identified in Canada.

Identification of Burkholderia cenocepacia genes required for bacterial survival in vivo

Burkholderia cenocepacia (formerly Burkholderia cepacia complex genomovar III) causes chronic lung infections in patients with cystic fibrosis. In this work, we used a modified signature-tagged mutagenesis (STM) strategy for the isolation of B. cenocepacia mutants that cannot survive in vivo. Thirty-seven specialized plasposons, each carrying a unique oligonucleotide tag signature, were constructed and used to examine the survival of 2,627 B. cenocepacia transposon mutants, arranged in pools of 37 unique mutants, after a 10-day lung infection in rats by using the agar bead model. The recovered mutants were screened by real-time PCR, resulting in the identification of 260 mutants which presumably did not survive within the lungs. These mutants were repooled into smaller pools, and the infections were repeated. After a second screen, we isolated 102 mutants unable to survive in the rat model. The location of the transposon in each of these mutants was mapped within the B. cenocepacia chromosomes. We identified mutations in genes involved in cellular metabolism, global regulation, DNA replication and repair, and those encoding bacterial surface structures, including transmembrane proteins and cell surface polysaccharides. Also, we found 18 genes of unknown function, which are conserved in other bacteria. A subset of 12 representative mutants that were individually examined using the rat model in competition with the wild-type strain displayed reduced survival, confirming the predictive value of our STM screen. This study provides a blueprint to investigate at the molecular level the basis for survival and persistence of B. cenocepacia within the airways.

Early intervention and prevention of lung disease in cystic fibrosis: a European consensus

In patients with cystic fibrosis (CF), early intervention and prevention of lung disease is of paramount importance. Principles to achieve this aim include early diagnosis of CF, regular monitoring of the clinical status, various hygienic measures to prevent infection and cross-infection, early use of antibiotic courses in patients with recurrent or continuous bacterial colonisation and appropriate use of chest physiotherapy.

Infection control in cystic fibrosis

Over the past 20 years there has been a greater interest in infection control in cystic fibrosis (CF) as patient-to-patient transmission of pathogens has been increasingly demonstrated in this unique patient population. The CF Foundation sponsored a consensus conference to craft recommendations for infection control practices for CF care providers. This review provides a summary of the literature addressing infection control in CF. Burkholderia cepacia complex, Pseudomonas aeruginosa, and Staphylococcus aureus have all been shown to spread between patients with CF. Standard precautions, transmission-based precautions including contact and droplet precautions, appropriate hand hygiene for health care workers, patients, and their families, and care of respiratory tract equipment to prevent the transmission of infectious agents serve as the foundations of infection control and prevent the acquisition of potential pathogens by patients with CF. The respiratory secretions of all CF patients potentially harbor clinically and epidemiologically important microorganisms, even if they have not yet been detected in cultures from the respiratory tract. CF patients should be educated to contain their secretions and maintain a distance of >3 ft from other CF patients to avoid the transmission of potential pathogens, even if culture results are unavailable or negative. To prevent the acquisition of pathogens from respiratory therapy equipment used in health care settings as well as in the home, such equipment should be cleaned and disinfected. It will be critical to measure the dissemination, implementation, and potential impact of these guidelines to monitor changes in practice and reduction in infections.

Controlling healthcare-associated infections: the role of infection control and antimicrobial use practices

Healthcare-associated infections are a major cause of morbidity and mortality in pediatric patients in the United States and throughout the world. Overall rates of infection range widely depending on the pediatric population, with the highest rates being in patients in neonatal intensive care units, followed by those in pediatric intensive care units, immunocompromised patients, and those undergoing surgical procedures. Risk factors for healthcare-associated infection include intrinsic and extrinsic factors. The major intrinsic factors are age, birth weight, underlying diseases, and immune status. The major extrinsic factors are presence of invasive devices and procedures. The major risk factors for healthcare-associated infection caused by antimicrobial-resistant pathogens are either the transmission of pathogens from person to person (directly or indirectly, usually via the hands of healthcare workers) or the emergence of resistance after exposure to antimicrobials. Preventing healthcare-associated infections caused by antimicrobial-resistant pathogens requires a comprehensive approach that includes: 1) preventing infections through the use of vaccines and prophylaxis; 2) minimizing the use of invasive devices; 3) understanding and fully implementing (and complying with) current guideline recommendations for the prevention of infections; and 4) using antimicrobials judiciously. Implementing such a comprehensive program will reduce healthcare-associated infections, reduce the prevalence of antimicrobial-resistant pathogens, improve patient outcomes, and reduce health care costs.

Pathophysiology and management of pulmonary infections in cystic fibrosis

This comprehensive State of the Art review summarizes the current published knowledge base regarding the pathophysiology and microbiology of pulmonary disease in cystic fibrosis (CF). The molecular basis of CF lung disease including the impact of defective cystic fibrosis transmembrane regulator (CFTR) protein function on airway physiology, mucociliary clearance, and establishment of Pseudomonas aeruginosa infection is described. An extensive review of the microbiology of CF lung disease with particular reference to infection with P. aeruginosa is provided. Other pathogens commonly associated with CF lung disease including Staphylococcal aureus, Burkholderia cepacia, Stenotrophomonas maltophilia, Achromobacter xylosoxidans and atypical mycobacteria are also described. Clinical presentation and assessment of CF lung disease including diagnostic microbiology and other measures of pulmonary health are reviewed. Current recommendations for management of CF lung disease are provided. An extensive review of antipseudomonal therapies in the settings of treatment for early P. aeruginosa infection, maintenance for patients with chronic P. aeruginosa infection, and treatment of exacerbation in pulmonary symptoms, as well as antibiotic therapies for other CF respiratory pathogens, are included. In addition, the article discusses infection control policies, therapies to optimize airway clearance and reduce inflammation, and potential future therapies.

Epidemic spread of Pandoraea apista, a new pathogen causing severe lung disease in cystic fibrosis patients

We show that Pandoraea apista must be added to the increasing list of pathogens capable of causing chronic lung infection in cystic fibrosis (CF) patients. It is most likely that this strain of P. apista was transmissible among patients with CF, leading to spread of infection from the index patient to 5 other patients exposed during participation in winter camps and/or hospitalization. All patients developed chronic infection with high levels of antibodies, and 4 patients had a downhill course of lung disease. P. apista must therefore be considered a new and sometimes important pathogen for CF patients. Cohort isolation prevented further spread of P. apista in our CF center.

Approach to resistant gram-negative bacterial pulmonary infections in patients with cystic fibrosis

PURPOSE OF THE REVIEW

Patients with cystic fibrosis are living longer with chronic pulmonary bacterial infections. One consequence of antibiotic treatment of these chronic infections has been the increasing prevalence of antibiotic resistance seen in bacterial isolates recovered from patients with cystic fibrosis.

RECENT FINDINGS

Bacteria such as Pseudomonas aeruginosa and Burkholderia cepacia are able to acquire antibiotic resistance by either spontaneous mutation or gene transfer via plasmids or integrins. In addition, bacteria survive by forming antibiotic-resistant biofilms within the airways of patients with cystic fibrosis. Therapeutic approaches to dealing with antibiotic-resistant bacterial pulmonary infections include the use of in vitro synergy testing to determine optimal double antibiotic combinations or multiple-combination bactericidal testing to determine bactericidal double and triple antibiotic combinations to use against the bacteria in the clinical setting of acute exacerbations.

SUMMARY

Therapy for antibiotic-resistant bacterial infections in cystic fibrosis involves the use of new laboratory methods (synergy testing or multiple-combination bactericidal testing) to optimize antibiotic treatment strategies. Clinical trials are required to address whether treatment guided by susceptibility testing improves clinical outcomes. Future novel approaches will likely include drugs that can disrupt bacterial biofilm formation and the use of cationic peptide antimicrobial compounds.

Infection control recommendations for patients with cystic fibrosis: microbiology, important pathogens, and infection control practices to prevent patient-to-patient transmission

Infection Control Recommendations for Patients With Cystic Fibrosis: Microbiology, Important Pathogens, and Infection Control Practices to Prevent Patient-to-Patient Transmissionupdates, expands, and replaces the consensus statement,Microbiology and Infectious Disease in Cystic Fibrosispublished in 1994. This consensus document presents background data and evidence-based recommendations for practices that are intended to decrease the risk of transmission of respiratory pathogens among CF patients from contaminated respiratory therapy equipment or the contaminated environment and thereby reduce the burden of respiratory illness. Included are recommendations applicable in the acute care hospital, ambulatory, home care, and selected non-healthcare settings. The target audience includes all healthcare workers who provide care to CF patients. Antimicrobial management is beyond the scope of this document.

Risk factors for Burkholderia cepacia complex colonization and infection among patients with cystic fibrosis

OBJECTIVES

To determine risk factors for acquiring Burkholderia cepacia complex among patients with cystic fibrosis (CF).

STUDY DESIGN

A case-control study was conducted with active surveillance for B cepacia complex colonization/infection among patients at 21 CF centers from April 1986 to March 1989 (study period). A case-patient was defined as any CF patient with B cepacia complex colonization for the first time during the study period. Control patients were patients with CF not B cepacia complex colonized during the study period. For each patient, a questionnaire was completed semiannually.

RESULTS

In multivariate analyses, hospitalization for pulmonary exacerbations, living with a B cepacia complex-positive person, attending a CF summer camp, and direct contact with a B cepacia complex-colonized CF person outside of camp and home were associated with B cepacia complex acquisition. Receiving antimicrobial aerosol therapy or cleaning and drying a home-used nebulizer between uses were associated with a decrease in B cepacia complex acquisition.

CONCLUSIONS

Numerous factors inside and outside the health care setting are associated with person-to-person transmission of B cepacia complex among patients with CF. Prevention programs should reduce direct or indirect contact between noncolonized and B cepacia complex-colonized/infected patients with CF.

Epidemiology of Burkholderia cepacia complex in patients with cystic fibrosis, Canada

The Burkholderia cepacia complex is an important group of pathogens in patients with cystic fibrosis (CF). Although evidence for patient-to-patient spread is clear, microbial factors facilitating transmission are poorly understood. To identify microbial clones with enhanced transmissibility, we evaluated B. cepacia complex isolates from patients with CF from throughout Canada. A total of 905 isolates from the B. cepacia complex were recovered from 447 patients in 8 of the 10 provinces; 369 (83%) of these patients had genomovar III and 43 (9.6%) had B. multivorans (genomovar II). Infection prevalence differed substantially by region (22% of patients in Ontario vs. 5% in Quebec). Results of typing by random amplified polymorphic DNA analysis or pulsed-field gel electrophoresis indicated that strains of B. cepacia complex from genomovar III are the most potentially transmissible and that the B. cepacia epidemic strain marker is a robust marker for transmissibility.

Distribution of quorum-sensing genes in the Burkholderia cepacia complex

The distribution of quorum-sensing genes among strains from seven genomovars of the Burkholderia cepacia complex was examined by PCR. cepR and cepI were amplified from B. cepacia genomovars I and III, B. stabilis, and B. vietnamiensis. cepR was also amplified from B. multivorans and B. cepacia genomovar VI. bviIR were amplified from B. vietnamiensis. All genomovars produced N-octanoyl-L-homoserine lactone and N-hexanoyl-L-homoserine lactone. B. vietnamiensis and B. cepacia genomovar VII produced additional N-acyl-L-homoserine lactones.

Diversity of the Burkholderia cepacia complex and implications for risk assessment of biological control strains

The Burkholderia cepacia complex (Bcc) consists of several species of closely related and extremely versatile gram-negative bacteria found naturally in soil, water, and the rhizosphere of plants. Strains of Bcc have been used in biological control of plant diseases and bioremediation, while some strains are plant pathogens or opportunistic pathogens of humans with cystic fibrosis. The ecological versatility of these bacteria is likely due to their unusually large genomes, which are often comprised of several (typically two or three) large replicons, as well as their ability to use a large array of compounds as sole carbon sources. The original species B. cepacia has been split into eight genetic species (genomovars), including five named species, but taxonomic distinctions have not enabled biological control strains to be clearly distinguished from human pathogenic strains. This has led to a reassessment of the risk of several strains registered by the U.S. Environmental Protection Agency for biological control. We review the biology of Bcc bacteria, especially how our growing knowledge of Bcc ecology and pathogenicity might be used in risk assessment. The capability of this bacterial complex to cause disease in plants and humans, as well as to control plant diseases, affords a rare opportunity to explore traits that may function in all three environments.

Clinical outcome after acquisition of Burkholderia cepacia in patients with cystic fibrosis

BACKGROUND

Respiratory disease is the major cause of morbidity and mortality in cystic fibrosis (CF). The significance of Burkholderia cepacia (B. cepacia) in the pathogenesis of lung disease in CF is debated, but its exact role remains unclear.

AIM

To assess the impact of respiratory tract colonisation with B. cepacia in patients with CF by measuring changes in pulmonary function and body mass index (BMI).

METHODS

Three groups of patients were defined based on sputum culture isolates: Group 1 were B. cepacia and Pseudomonas aeruginosa (P. aeruginosa) positive patients; Group 2 were P. aeruginosa positive; and Group 3 were colonised with neither organism. Forced expiratory volume (FEV) and BMI were measured annually from 1987 to 1995 and the year of acquisition of P. aeruginosa or B. cepacia was recorded.

RESULTS

The mean annual decrease in FEV1 was significantly different in all three groups: Group 1, -5.4 (5.1)%; Group 2, -3.9 (6.5)%; and Group 3, -1.6 (1.0)%, (p<0.05). The mean percentage decrease in FEV1 of a sub-group of Group 1 patients where the B. cepacia acquisition date was known was 6.1% per year versus 1.55% in Group 2 patients (p<0.05).

CONCLUSIONS

Acquisition of B. cepacia may be a cause of, rather than a marker for, a decrease in pulmonary function.