All proceeds from '65km for Cystic Fibrosis' will be directed to CF research or research that improves the quality of CF care in hospitals as this is known to be essential for good health outcomes.
To date we have funding the following projects:
2018 - Monash Foundation
defining the presence of macrophage and neutrophil extracellular traps as a therapeutic target in early-stage cystic fibrosis – Extension funding from 2017
Dr. Paul King – Monash Health
We wish to study a potentially important inflammatory pathway in early-stage cystic fibrosis (CF) lung disease; the production of neutrophil extracellular traps (NETs) and macrophage extracellular traps (METs). These NETs and METs are produced in the lung by the lung white cells (phagocytes), mainly in response to infection. They are composed of extracellular DNA with an attached protein called a protease. These proteases are a key chemical causing lung damage in CF.
The NETs and METs can be broken down by a chemical called deoxyribonuclease (DNase), which reduces the expression of the damaging proteases in the lung. DNase is available as a standard therapy for patients with CF in the form of Pulmozyme. Pulmozyme is used in older children and adults to break down bacterial DNA and improve sputum clearance.
We have developed expertise to study the production of NETs and METs in the lung. We believe that no other centre in the world has this expertise. We have completed preliminary work in 14 children (8 control/6 CF patients). This work has demonstrated; 1) the baseline expression of traps in lung samples, 2) the addition of the bacteria to the samples increases trap expression and, 3) the addition of DNase to bacteria-infected samples abolishes trap expression. We would like to build on these findings to produce a detailed study that will be publishable in a high quality journal.
To do this we are planning on incorporating the Royal Childrens Hospital (RCH) so we have a multi-site study. This work will provide a rationale to use Pulmozyme in early life in children with CF. The Pulmozyme may reduce harmful inflammation by inhibiting trap formation. This may prevent lung damage and result in better longterm outcomes in children with CF.
Combating Pseudomonas aeruginosa infections in paediatric patients with cystic fibrosis
Dr. Cornelia Langersdorfer – Monash University
Lung infections by Pseudomonas aeruginosa (Pa) cause ill-health and death in patients with cystic fibrosis (CF). It is imperative to effectively treat these infections in paediatric patients to prevent development of resistant Pa, as once an antibiotic-resistant Pa infection has been established in CF patients, it is extremely difficult to treat. Current single antibiotic treatments are increasingly ineffective and combination regimens have never
been scientifically optimised against Pa infections of paediatric CF patients. This project will develop an improved treatment, using combinations of available antibiotics, that effectively kills Pa from paediatric CF patients and prevents resistance development.
Our laboratory infection models will precisely mimic the antibiotic concentrations over time as would be observed in the patients. We will use genetic studies to identify the mechanisms by which resistance develops for the current standard (non-optimised) clinical dosage regimens. Novel mathematical models will be developed to describe the antibiotic effects for different treatment regimens. These mathematical models will then be used to design an optimized antibiotic combination regimen that effectively kills Pa and prevents resistance development. This optimised combination regimen will be tested experimentally for effectiveness in our laboratory studies.
Overall, this project will design an optimised treatment regimen that demonstrates effective bacterial killing and prevents resistance development of Pa in the laboratory. Our optimised regimen will ultimately be able to be translated for future studies in patients, and subsequently it is expected that the results will guide doctors on how to treat Pa infections in paediatric patients with CF more effectively.
The airway microbiota in advanced cystic fibrosis lung disease: its relationship to early life factors
Dr Katherine Frayman - PhD Candidate; Respiratory Paediatrician
This study will describe the relationship between the bacterial community (microbiota) found in the sputum of adults with cystic fibrosis (CF) and early life factors, including the bacterial community in lower airway samples from infancy and early childhood. Infection and inflammation are intricately related to the development and progression of CF lung disease.
Historically, we believed that people with CF became infected with 1-2 of a small number of bacteria. More recently, studies using molecular techniques have demonstrated that there are complex bacterial communities in both healthy and CF airways, and that in CF, certain characteristics of these communities are associated with poorer outcomes. In the early 1990s, a birth cohort of Victorian infants with CF was established with the aim of exploring the role of infection in the development of CF lung disease. Participants underwent bronchoalveolar lavage (BAL; lung washings) under general anaesthetic approximately yearly during early childhood. Molecular analyses have been performed to describe the bacterial communities in their BAL fluid.
We are currently conducting a long term follow up study of this birth cohort, exploring the impact of early lower airway infection and inflammation of survival and on the development of lung disease over 25 years. This study will involve the molecular analysis of sputum samples collected from these adults, in order to describe the sputum microbiota. We will compare the early childhood and adult lower airway microbiota, and explore the relationship between early life factors and the sputum microbiota, therefore improving our understanding of the development of CF lung disease.
2017 - Monash Foundation
Defining the presence of macrophage and neutrophil extracellular traps as a therapeutic target in early-stage cystic fibrosis.
Doctor Paul King - Monash Health
$ 44,815 grant
We wish to study a potentially important inflammatory pathway in early-stage cystic fibrosis lung disease - the production of neutrophil extracellular traps (NETs) and macrophage extracellular traps (METs). These NETs and METs are produced in the lung by the white cells, mainly in response to lung infection. They are composed of extracellular DNA with an attached protein called a protease. These proteases are a key chemical causing lung damage in CF.
The NETs and METs can be broken down by a chemical called DNase, which reduces the expression of the damaging proteases in the lung. DNase is available as a standard therapy for patients with CF – Pulmozyme is used in older children and adults to break down bacterial DNA and improve sputum clearance.
We expect to find that NETs and METs are present in the lungs of young children with CF. We also expect to show that when we add DNase/Pulmozyme in a test tube this will prevent the expression of these NETs/METs and their damaging proteases.
This may lead to clinical trials of Pulmozyme in early-stage CF, which may decrease damaging inflammation. This anti-inflammatory effect at a critical stage of lung development may improve the long-term outcome in children with CF.
This work is relevant to both chronic sinus disease and ABPA.
Efficacy of sinonasal inhalation of hypertonic saline in people with rhinosinusitis and cystic fibrosis.
Amanda Nichols, Physiotherapist - Monash Health
$ 20,596 grant
We now know that sinus disease is frequently present in those living with CF with one study reporting CT changes in almost 100% of their group (Eggesbo et al 2001) and another reporting that only 7% of their group did not demonstrate any evidence of sinus disease (Babinski, Trawinska-Bartnicka 2008).
This is incredibly significant as these symptoms have a large impact, not only on quality of life but also on the progression of disease more generally. We now have many options for treating infections in the lungs, however, if the source of infection is in the sinuses, these treatments may either be unsuccessful in treating the infection or preventing recurrence.
We aim to investigate whether inhaling 6% hypertonic saline directly into the sinuses (using the Pari Sinus) will improve sinus symptoms, quality of life and amount of infection in people living with CF and sinus disease. We aim to do this by trialling this treatment with our adults once daily, for three months. We will monitor the effect of this treatment by obtaining nasal lavage samples and Sino-Nasal Outcome Test (SNOT-22) test results pre and post treatment. We will also conduct a the CFQ-R to measure quality of life before and after. As secondary measures we will also monitor FEV1 and sleep quality using the Epworth Sleepiness Scale(ESS) and the Pittsburgh Sleep Quality Index (PSQI).
We hope that this treatment will improve quality of life in our adults with CF and sinus disease. We also hope it will decrease sinus symptoms and amount of infection.
Cystic Fibrosis Related Diabetes (CFRD) Model of care: Optimising patient centred Healthcare Delivery in the Inpatient and Outpatient Setting
Georgia Soldatos, MBBS, FRACP, PhD
$ 50.000 grant
The development of CFRD is associated with poorer outcomes including impaired nutritional status, reduced body mass index (BMI), more frequent pulmonary exacerbations, increased prevalence of Pseudomonas aeruginosa colonisation, and lung function decline. Optimal management of CFRD is important to improve these outcomes.
Despite clear national guidelines regarding management of CFRD, regular attendance at Diabetes clinics for people who may already have a significant burden of disease relating to other organ systems, remains challenging. Data from the Monash Health CF service reveals that adherence to recommended annual oral glucose tolerance testing is very poor, with 25% of patients not having an OGTI performed in the preceding three years. In addition, compliance with regular, fingerprick glucose testing is difficult to achieve in clinical practice.
In collaboration with people living with CFRD, we aim to develop the optimal, patient centred, multidisciplinary, evidence based model of care in order to improve attendance, engagement and ultimately, clinical outcomes. Furthermore, we propose to use glucose sensors for glucose monitoring during and following acute exacerbations, not only in the clinical context of patients with known CFRD but also in this research setting in those with normal or impaired glucose tolerance. By utilising this innovative technology, which we predict will be appealing to patients, we will gain insights into the glucose profiles of people with CF admitted with pulmonary exacerbations. This data, if validated, will inform clinical decisionmaking regarding management of previously, undetected glucose excursions.
2016 - Monash Foundation
Is implementation of the 2006 Australasian Clinical Practice Guidelines for nutrition in cystic fibrosis associated with improvements in nutritional status?
Associate Professor David Armstrong - Monash Childrens
$ 22,200 grant
This project will examine whether the Australasian Clinical Practice Guidelines for nutrition in cystic fibrosis, implemented in 2006, are associated with improvements in the nutritional status of children participating in the Australian Cystic Fibrosis Data Registry (ACFDR).
Nutrition in children with CF is important because poor nutrition is a risk factor for poor outcomes. However, poor nutrition remains a problem in CF because of increased energy requirements and problems with fat and protein absorption. To help address this, Australasian guidelines for dietitians for the nutritional care of CF children were introduced in 2006. These guidelines make suggestions for dietitians to help children with CF eat well and grow optimally. However, whether the nutritional status in children with CF has improved since the introduction of the guidelines has not been evaluated and will be examined in this study.
The study extract the nutritional status data of children with CF in the ACFDR from 1998 and compare growth data before 2006 and after 2006 using statistical modelling. It will explore whether there were problems implementing the guidelines, by conducting an online survey among stakeholder groups (such as dietitians, doctors, nurses and patents).
It is expected the study will show improved nutritional status in children after the introduction of the guidelines and identify what were the enablers and barriers to implementing the guidelines. This will help inform implementation strategies for the soon to be released updated Australasian nutrition guidelines for CF
Cystic Fibrosis (CF) questionnaire assessing disease knowledge in adolescents with CF
Dr. Moya Vandeleur - Monash Health
$ 30,271 grant
Transition to adult care is a major life event for young people with cystic fibrosis. Many studies have reported that a successful transition partly relies on sufficient knowledge about CF; the disease itself and treatment plans. A higher level of knowledge has been correlated with better disease self-management and treatment compliance.
Monash has a robust transition process as paediatric patients transfer to co-located adult service or from Royal Children's Hospital. However, relatively little is known about disease specific knowledge of our adolescent patients with CF and their parents. As part of an initiative to improve the CF transition processes at Monash Children's Hospital (MCH) and RCH, we aim to develop a reliable questionnaire to investigate general knowledge about CF in both adolescents and their parents. To validate its use in a larger population we plan to collaborate and pilot the questionnaire at both MCH and the RCH. Potential participants include all young people with CF aged 11-18 years (and their parents/careers) attending the CF out patient service at MCH and RCH.
The purpose of this project is to improve the CF transition process at MCH and RCH by developing a questionnaire that will evaluate knowledge in transitioning young people and measure the effectiveness of the CF team in communicating information about cystic fibrosis.
2015 - MCRI
How does activation of PAR1 (Protease-activated receptor-1) modify the response of lung immune cells in cystic fibrosis?
Associate Professor Phil Sutton
$ 45,339 Grant
Infection of the lung with bacteria is an important part of the disease-causing process in cystic fibrosis. In CF, these bacteria trigger an inflammatory response that recruit immune cells that cause lung damage and help drive progression to more serious lung disease. Control of these infections – or the inflammation that they produce – is an important feature of CF clinical management.
We have identified a factor, expressed by some immune cells, which may be able to be used to reduce the inflammatory response of these cells upon infection with disease-causing bacteria. However this effect is highly variable; targeting this factor reduces the inflammatory response of lung cells from only some people with CF. This project aims to increase our understanding of the conditions under which this factor is expressed by immune cells in CF, in order to help explain this variability. This will be valuable for determining if and how it may be developed as a possible treatment for lung inflammation in CF.
REPORT, NOVEMBER 2016: Protease Activated Receptor 1 (PAR1) is a molecule found on the surface of many different cell types, including those of the immune system, which has been shown to be able to change the severity of inflammation in a range of different diseases. We have been examining whether PAR1 might play a role in changing the severity of inflammation in the CF lung and, if so, whether it might therefore provide a novel therapeutic target.
The studies we have performed so far suggest that activation of PAR1 might modify the inflammatory response to pathogenic bacterial infection in lung immune cells some children with CF. Due to the high degree of variability of this effect, it does appear unlikely at this time that this approach would have widespread therapeutic benefit. However we are continuing our studies to get a better understanding of what PAR1 does in the CF lung in case there is still a potential approach we might be able to use.
Modelling complex variation in multiple breath washout (MBW) data to reveal unobserved characteristics of early childhood lung disease in cystic fibrosis
Professor John Carlin
$ 31,520 Grant
The multiple breath washout (MBW) technique has been widely adopted by respiratory researchers because of its usefulness in assessing lung function for various common and serious lung diseases, particularly cystic fibrosis (CF). Currently, MBW data are typically interpreted using simple summaries only, yet the data are rich in additional information that could be extracted using methods that have not previously been applied in respiratory research.
We will develop and apply sophisticated statistical models and techniques to MBW data using state-of-the-art software. We expect to reveal properties of the data that are clearly connected to the underlying lung biology. These advances will give researchers new perspectives on early childhood lung function, with a particular focus on identifying early markers of disease progression in CF.
A longer-term goal is the refinement of MBW and similar techniques to make them suitable for clinical use.
REPORT, NOVEMBER 2016: The MBW technique has been widely adopted by respiratory researchers because of its usefulness in assessing lung function of various common and serious lung diseases, particularly cystic fibrosis.
In this project we have developed and applied sophisticated statistical models and techniques to MBW data, and we expect in continuing work to reveal properties of the data that are clearly connected to the underlying lung biology. These advances will give researchers new perspectives on early childhood lung function, with a particular focus on identifying early markers of disease progression in CF.
A related goal is the refinement of MBW and similar techniques to make them suitable for clinical use. Improving the statistical methodology has taken us closer to this goal and we expect our findings from analysis of research data to demonstrate the clinical utility of these techniques. This research should make MBW testing more useful and cost-effective for both research and clinical purposes, thus providing a powerful tool for the study and management of CF.
We believe that we have generated new data and an interesting mathematical analysis that will be of interest to the CF community as new treatment trials use the MBW test. Our method means even when the testing time is short, as is often the case in young children, or relatively short as it may be in those who are sicker, useable results will be available in more children.
Role of an acute phase protein Alpha 1-acid glycoprotein as a biomarker of prediction of pulmonary exacerbation in young patients with cystic fibrosis
Rosemary Carzino - Progress Report
$ 41,367 Grant
SUMMARY: This project is to investigate if a specific blood protein can act as a “biomarker” to detect for the presence of a lung infection. Blood concentrations of these proteins are found to increase in response to the presence of inflammation and infection.
This protein has not yet been tested in children with CF and as part of the AREST CF program, we have an opportunity to study the blood samples that have already been collected and stored. These results will be studied alongside other information collected at the same time; including BAL, Chest CT, and lung function tests.
An early predictor of lung infection using a relatively simple blood test could help provide the information medical staff require to begin immediate treatment. Early intervention could help slow down lung disease leading to better long term health.
REPORT, NOVEMBER 2016: This project aims to investigate the role of an acute phase protein in blood as a biomarker for the prediction of a pulmonary exacerbation in young patients with CF.
To date we have not yet analysed any data for this project as the samples are currently being tested and results are yet to be received. Upon discussion, we have decided to change direction in methodology and send the samples off to a biomedical company in Finland. This means that besides analysing for the acute phase protein levels in question, a further 200 other biomarkers can also be tested simultaneously in a small volume of one sample by the use Nuclear Magnetic Resonance technology. This allows for a great opportunity to work alongside other groups in MCRI who are also utilising this service where results may be compared for further analysis.
Once results are received, they will be analysed alongside relative clinical information to ascertain the ability of the acute phase blood protein to predict a pulmonary exacerbation in young children with CF, with the added benefit of exploring other blood biomarkers in the meantime.
2014 - MCRI
feasibility of human Epithelial Cell culture from Bronchial Brushings of cystic fibrosis patients for studies of airway modelling and research.
Paul Griffin, Cilial Function Scientist
SUMMARY: In this project we will use samples obtained from bronchial brushings obtained during broncho-alveolar lavage to establish a novel model and validate an in vitro model. This model can then be used to study a variety of conditions, including pathogenesis of, and recovery from various infectious organisms and the effects of environmental physiological changes on the respiratory epithelium. This will be done by growing the cells in an air-liquid interface culture using antibiotic media. The antibiotic clears infections in the sample allowing the cells to re-differentiate into “clean” new, airway epithelia. The cells are then challenged under different conditions and a comparison can be made to normal airway epithelia. Changes in the gross structure, function and ultrastructure of the cells will be analysed using high speed video and electron microscopy (and possibly fluorescence microscopy).
The model can further be used to test a wide range of pathogens in addition monitoring the time it takes to completely recover to normal function and the influence of pH on epithelial and ciliary function.
The aim is to adapt the cell culturing technique currently used on nasal epithelial brushings for bronchoscopic brushings from CF patients. Once validated, a functional and biologically representative cell model can be used to perform experiments. If successful, a second aim of this project would be to investigate the pathogenic sequence of infection of bacteria commonly isolated from CF specimens. The model can be used to check the time of clearance of the bacteria using antibiotics and how long recovery of normal function takes. Also, the effect on important aspects of the airway including cilia beat frequency and differences in ultrastructural components can be monitored. Thirdly, environmental conditions such as the pH of the media and Sodium Bicarbonate levels can be varied and again, the effects on functions and structure of the cells can be observed.
Very little detailed work has been reported on primary, differentiated CF airway epithelial cell culture. Most studies are done on explants or expensive commercial cell lines which are not as relevant. This project will provide an improved cell culture system for respiratory research that can provide novel experimental investigations. It also has the potential to allow for individual reports on patient samples. Our wealth of experience in cell culture, with the addition of world leading equipment and support (currently utilised in the RCH PCD diagnostic service), have shown images and videos produced here, are of the highest quality. Also, as it is thought that this method of culture should be more successful, it would therefore in theory, reduce the expense and time spent on culturing samples that fail to thrive.
A success model would be attractive to scientists and clinicians studying mucosal immunology, CF airway therapeutics and a myriad of other disciplines. To our knowledge, less than a handful of centres in the world possess this model for studying young children with CF.
REPORT: A clinical method for the brushing of Cystic Fibrosis patient’s airways was established. This was based on a method already in use at another hospital, altered to suit our project purposes and facilities.
Over 20 procedures have been performed, with no adverse effects. After overcoming a few problems, several individual samples have grown to the point where cilia function and mucus production was observed. To validate that a true CF airway cell environment had been generated, visualisation of this cell strata has been produced in two ways. A high speed video of the cilia beating was recorded and slowed down to a tenth of the actual speed, so the frequency and shape of the beat could be seen. These were both completely normal in all videos of the samples taken. The second method of visualisation was via electron microscope, where the structures of the cell organelles (including cilia) could be checked and confirmed to be as expected. This microscope allows magnification of the cells up to 30,000 times. Again, in all aspects of the cell formation, the structure was found to be as expected in a CF patient. There are still a few hurdles to overcome, and currently the correlation between health of patient at the time of brushing and the success rate of culture is being investigated. However, the successes so far have meant we can start to design and perform further experiments to characterise aspects of CF airways that likely could not be studied any other way.
Evaluating the role of elastase in the inflammatory response in cystic fibrosis
Associate Professor Phil Sutton, Group Leader, Mucosal Immunology
SUMMARY: CF patients are highly susceptible to respiratory infections that result in life-threatening inflammation in their lungs. A/Prof Ranganathan has identified that a protease (an enzyme that cuts up proteins) called neutrophil elastase is significantly associated with CF pathogenesis. This elastase is probably produced in response to infection of the lung.
This project builds on a finding of potentially major significance that was published in one of the top medical journals.
Our findings indicate that the detection of free neutrophil elastase in lower respiratory secretions is associated with the development of early bronchiectasis in CF. The aim of this project is to investigate the potential use of this observation to identify suitable new targets for therapy in CF. This proposal will provide a proof-of-concept test of a theory regarding how we believe neutrophil elastase contributes to bronchiectasis in the airways. If correct this will identify new ways to prevent the pathway to destructive lung damage.
An important additional significant bonus of this project is that it will establish the CF mouse model at MCRI. Its introduction will increase the variety of techniques available for CF research.
This project is evaluating whether the protease activated receptors PAR1 and/or PAR2 play an important role in CF pathogenesis. The funded project aims to: 1) Establish a colony of Cftr mutant mice at MCRI. These would be used to provided cells and tissues for important tissue culture experiments. 2) Cross these Cftr mutant mice with mice lacking PAR1 or PAR2 in order to provide an animal model for examining what effect the PAR receptors have on CF pathology. 3) Examine the interaction of PAR1 and the CF mutation in human cells.
REPORT: We have had good success with examining the role of PARs and in particular PAR1 in CF.
We have started to examine the importance of PAR1 on the response of immune cells present in the lungs of children with CF. Importantly, we have found activation of PAR1 on these immune cells reduces or prevents the inflammatory response to stimulation with the important CF pathogenic bacterium, Pseudomonas aeruginosa. In other words, PAR1 activation may reduce the inflammatory response of CF immune cells.
We have also purchased neutrophil elastase and have started examining how this interacts with PARs using lung immune cells from CF children.
We have done considerable work on using a technology called “CRISPR” to be able to knock-out CFTR expression in any cell line we choose. CRISPR plasmids for targeting Cftr have been designed, made and tested successfully. We will soon start to make Cftr knock-out cell lines and use them in our studies.
We have very encouraging preliminary data suggesting activation of PAR1 may inhibit the inflammatory response of lung immune cells from some CF children; this may indicate a potential new therapeutic target. We are also developing powerful new tools to allow us to perform important tissue culture experiments that will help us evaluate this possibility.
2013 - MCRI
exploring the early lung microbiota in cystic fibrosis
SUMMARY: New techniques have revealed that a much larger range of organisms than we previously believed colonise the human lung. These microbes are called the microbiota. We don't know which organisms reside in the lungs of people with CF. We believe it is important to study this as we have identified that the lungs can be damaged in CF before typical infections are detected. We hope that by turning our attention to different microbes that might be present in the lungs early in life and that may initiate the inflammation that causes damage to the structure of the lung.
The Royal Children's Hospital and MCRI previously (1992-1995) stored a unique resource of lower respiratory and saliva samples from infants and young children with CF, together with samples from controls without CF who underwent lung washings for investigation of other diseases. Together with our leading team of scientists from the Human Microbiome Project in the US, we want to analyse these samples in order to explore the range of microbes in early CF. This will enable us to investigate several important questions about the potential role of the microbiota in the development of CF lung disease.
REPORT (January 2015): Microbial diversity in lung fluid
Our analysis has now revealed the relative abundance of genera identified in the historic BAL samples from children with CF treated at RCH using 16s PCR sequencing. Deep sequencing is ongoing and will be used to identify individual bacterial species, virulence patterns and antibiotic resistance genes. Dr Katherine Frayman will be looking at long term clinical outcomes in relation to these early data. We are currently exploring how these sequencing data relate to conventional microbial culture and other aspects of disease pathogenesis and important clinical outcomes in preparation for publication. We will be the first group able to report on the microbiota in relation to inflammation and other clinical outcomes and so a manuscript is in preparation.
Differences between the left and right lung
We have assessed the number of reads and the relative abundance respectively of microbial genera in lung fluid samples obtained from the left and right lung. Where there were sufficient reads using 16s sequencing on BAL samples obtained from the left and right lung we identified that microbial genera were similar in most cases. In one case, there was a stark difference between left and right lung: the genus Staphylococcus was identified in the right lung but diverse flora in the left. We are investigating pulmonary inflammatory markers and evidence for regional structural lung damage in these individuals. This is a unique approach as few centres have recourse to such samples from the left and right lung.
Changes in the microbiota over time
In 15 subjects at least three BAL samples were analysed successfully so that changes in the microbiome over time can be analysed. Again, the data are unique because we are able to compare the microbiome with changes that occurred in pulmonary inflammation, standard culture and clinical progress. We are writing up the results and believe they will be of great interest to the CF and respiratory research community in helping to better understand the microbiota in the CF lung.
Prevalence of small-colony variant s.aureus among children with CF
Dr Emily Hart
SUMMARY: Lung infections with the microorganism, Staphylococcus aureus, are common in young children with cystic fibrosis (CF). Many patients experience repeated infections during which time S. aureus adapts itself, becoming better suited to living in the human lung by forming what are known as small-colony variants (SCVs).
These changes make the bacteria more resistant against treatment with antibiotics and affect their ability to grow in the methods laboratories currently use to diagnose bacterial infections. Because this slower growth makes them more difficult to detect, at present we do not know whether SCVs in S. aureus are an important cause of infection in our patients.
This study will use updated diagnostic methods to specifically look for SCVs in respiratory specimens collected from patients attending the Royal Children’s Hospital (RCH) Melbourne, and we expect that SCV infections will be common in children with CF lung disease. Detection of these variants is particularly important, given their ability to resist treatment with certain antibiotics. Knowing the prevalence of this bacteria will help us to improve the way in which we diagnose respiratory infections in CF, and will also provide clinicians with more detailed information that can be used to optimise the treatment and management of their patients.
REPORT (January 2015): Twenty six children (mean age 11.35(5.05) years) from the AREST CF study (Melbourne) were identified with a positive S.aureus culture from lower respiratory tract specimens collected in 2014. All children were on at least one or multiple antibiotics prior to or at time of collection. The antibiotics were, namely Augmentin Duo (46%), Tobramycin (15%), Bactrim (11%), or other (27%). Fifty-seven percent of samples were visible on large MSA plates and subcultured onto wild-type HBA plates, but no SCVs of S.aureus were isolated.
Conclusion: SCV’s were not isolated from the lower airways specimens and therefore were not identified as contributing to lung infections in our cohort of young subjects with CF.
establishing predictive indicators of amino glycoside nephrotoxicity and the incidence of toxicity in children aged less than 6 years with CF
Ms Courtney Munro
SUMMARY: Cystic fibrosis (CF) is caused by a gene defect and affects the lungs and other body systems. People with CF have altered medicine metabolism. This is because CF affects how the body processes medicines.
Aminoglycosides are antibiotics commonly used in the treatment of CF. As CF is now mainly diagnosed by newborn screening, aminoglycosides are being used earlier than in the past. Thus people with CF are exposed to higher doses and to longer and repeated courses. This long and early exposure to aminoglycosides may pose risks that little is known about appropriate dosing or toxicity.
There are two important side effects from aminoglycosides. These are:
· kidney damage and;
· hearing loss or deafness.
The aim of this research project is to see if we can discover markers that show changes in kidney function, before and after treatment with aminoglycoside antibiotics. We will do this by testing blood and urine samples. The research project may help to find a marker of early kidney disease. This would help us to know when to reduce the dose of aminoglycoside or when to change the antibiotic to a different one, to prevent damage to the kidneys.
REPORT (January 2015): Patients under six years of age were recruited when commencing IV aminoglycosides (gentamcin 7.5 mg/kg or tobramycin 12 mg/kg) and had urinary and serum sampling of creatinine and magnesium. A total of seventeen patients aged 0.74-6.99 years, ten males, eight of them on gentamicin and nine of them on tobramycin, have been recruited to date. A total of 44 patients will be recruited.
Early results suggest that the metabolism and excretion of magnesium in CF warrants further study, and that aminoglycosides (gentamicin>tobramycin) considerably alter magnesium excretion.
Thank you to all 65km for Cystic Fibrosis participants and their supporters for generously supporting our research projects