Who are the 10%? - Non eligibility of cystic fibrosis (CF) patients for highly effective modulator therapies.

BACKGROUND: The availability of mutation-specific cystic fibrosis modulator therapies has the potential to improve the lives of children and adults with cystic fibrosis. The frequency of mutations causing defects in the cystic fibrosis transmembrane conductance regulator (CFTR) function varies between sub-groups in multi-ethnic populations. The profile of patients eligible for CFTR modulator ivacaftor/tezacaftor/elexacaftor (Kaftrio™) therapy based on ethnicity has not been reported in the United Kingdom CF population. METHODS: We conducted a descriptive cross-sectional analysis of patients in the UK CF Registry who had annual review data submissions in 2019. Data analysed included demographic characteristics, spirometry, chronic Pseudomonas status, nutrition, and CF related diabetes status. The genotype data was stratified by whether there was at least one copy of F508del or no copy of F508del as current eligibility for ivacaftor/tezacaftor/elexacaftor, or projected future eligibility, is defined as having at least one copy of F508del mutation. RESULTS: Data from 9887 patients were reviewed, 46.7% female, mean age 22.5 years. 8.6% (n = 852) patients had no copy of F508del making them ineligible for ivacaftor/tezacaftor/elexacaftor. Overall, 93.4% of patients were of white ethnicity, with a similar proportion of those with at least one F508del being white (95.6%). This was reduced to 70.0% of those with no F508del. The proportion of people of Asian ethnicity was much higher in the no F508del group (19.2% vs 1.2%). Compared with one F508del patients, the no F508del group were older (25.2 years vs 22.2 years, p < 0.001), had higher prevalence of pancreatic sufficiency (39.0% vs 14.9% p < 0.001), lower prevalence of chronic Pseudomonas infection (21.1% vs. 26.6%, p < 0.001), and higher best FEV1 from the previous year (proportion with greater than 70% FEV1 predicted, 66.1% vs 63.0%, p = 0.005). CONCLUSION: Patients from black, Asian and minority ethnic backgrounds are significantly less likely to be eligible for ivacaftor/tezacaftor/elexacaftor based on the current prescribing policy in the UK. At present this is the most highly effective CF modulator therapy available to treat people with CF. The CF community should urgently address the unmet need for effective targeted therapies for patients without F508del.

A prospective randomised controlled mixed-methods pilot study of home monitoring in adults with cystic fibrosis.

BACKGROUND: Home monitoring (HM) is able to detect more pulmonary exacerbations (PEx) than routine care (RC) in individuals with cystic fibrosis (CF), but there is currently no evidence for benefits in health outcomes. Patient experiences of using HM and a health economics assessment have not been rigorously assessed to date. This study aimed to assess the effects of HM on hospital admissions, quality of life, antibiotic requirements, exacerbation frequency, lung function, nutritional outcomes, anxiety, depression, costs and health outcomes, as well as the qualitative effects on the patient experience. METHODS: This randomised controlled mixed-methods pilot study recruited CF adults cared for in one large regional CF centre. Participants were randomly allocated 1:1 to the intervention cohort [twice-weekly HM of symptoms measured by the Cystic Fibrosis Respiratory Symptom Diary - Chronic Respiratory Infection Symptom Score (CFRSD-CRISS) and forced expiratory volume in one second (FEV1)] or a control cohort (routine clinical care) for the 12-month study period. Measurements were recorded at study visits at baseline, 3, 6, 9 and 12 months. Spirometry, body weight, comorbidities, medications, hospital inpatient days, courses of antibiotics (oral and intravenous) and PEx (defined by the modified Fuchs criteria) were recorded at each study visit. Health status, capability and cost-effectiveness were measured at each study visit by the Hospital Anxiety and Depression Scale (HADS), the ICEpop CAPability measure for Adults (ICECAP-A), EuroQol 5 dimensions (EQ-5D-5L) questionnaire and an adapted resource use questionnaire. The patient experience of HM was assessed by semi-structured qualitative interviews at baseline and 12 months. RESULTS: Eighty-eight participants were recruited, with 44 (50%) randomised to receive HM and 44 (50%) randomised to receive RC. Patient hospital inpatient bed days per annum and overall health-related quality of life were similar between the groups. Protocol-defined PEx requiring intravenous and oral antibiotics were detected more frequently in the HM group, with no other differences between the groups in the secondary outcomes. The total mean National Health Service (NHS) costs were approximately £1500 more per patient for the RC arm than the HM group. The qualitative analysis demonstrated that the patient experience of HM was generally positive and overall the intervention was well accepted. CONCLUSION: The findings of this trial confirm that HM is effective in detecting PEx in adults with CF. There were no significant differences in hospital inpatient bed days and overall health-related quality of life between the groups. Despite the cost of the HM equipment and the salary of the research fellow to respond to the results, health economics analysis suggests the intervention was less expensive than RC. HM was generally well accepted, with most participants reporting that it resulted in them feeling more empowered and reassured. TRIAL REGISTRATION: The study protocol was registered with Clinicaltrials.gov (NCT02994706) on 16 July 2014 and published in a peer reviewed journal.Data from this trial has been presented in abstract form at the ECFS Conference in Lyon in September 2020.

Porphyromonas pasteri and Prevotella nanceiensis in the sputum microbiota are associated with increased decline in lung function in individuals with cystic fibrosis.

Although anaerobic bacteria exist in abundance in cystic fibrosis (CF) airways, their role in disease progression is poorly understood. We hypothesized that the presence and relative abundance of the most prevalent, live, anaerobic bacteria in sputum of adults with CF were associated with adverse clinical outcomes. This is the first study to prospectively investigate viable anaerobic bacteria present in the sputum microbiota and their relationship with long-term outcomes in adults with CF. We performed 16S rRNA analysis using a viability quantitative PCR technique on sputum samples obtained from a prospective cohort of 70 adults with CF and collected clinical data over an 8 year follow-up period. We examined the associations of the ten most abundant obligate anaerobic bacteria present in the sputum with annual rate of FEV1 change. The presence of Porphyromonas pasteri and Prevotella nanceiensis were associated with a greater annual rate of FEV1 change; -52.3 ml yr-1 (95 % CI-87.7;-16.9), -67.9 ml yr-1 (95 % CI-115.6;-20.1), respectively. Similarly, the relative abundance of these live organisms were associated with a greater annual rate of FEV1 decline of -3.7 ml yr-1 (95 % CI: -6.1 to -1.3, P=0.003) and -5.3 ml yr-1 (95 % CI: -8.7 to -1.9, P=0.002) for each log2 increment of abundance, respectively. The presence and relative abundance of certain anaerobes in the sputum of adults with CF are associated with a greater rate of long-term lung function decline. The pathogenicity of anaerobic bacteria in the CF airways should be confirmed with further longitudinal prospective studies with a larger cohort of participants.

Perception, experience and relationship with food and eating in adults with cystic fibrosis.

BACKGROUND: Cystic fibrosis (CF) is a multisystem disorder that primarily affects the respiratory and gastrointestinal systems. Dietetic therapy is a prominent aspect of CF management, with patients receiving nutritional surveillance and advice throughout their lifetime. The present study aimed to explore the perception, experience and relationship with food and eating in adults with CF. METHODS: Semi-structured telephone interviews were conducted with nine adults with CF. Interviews were audio-recorded, transcribed verbatim and analysed thematically following a previously described six-phase procedure. RESULTS: Six themes were identified: 'Sustained influence of eating experience in childhood', 'Eating for health: weight gain to prevent infection', 'Balancing health and body image', 'I'm different,' 'Strategies for managing food intake' and 'Support from family, friends and the CF Team'. Participants talked about the range of strategies they employ, with a focus on eating well and choosing high calorie foods being an important part of their health management strategy. This is driven by the belief that a good weight ensures better health and perceiving eating as a treatment. CONCLUSIONS: This group felt able to cope well and had developed strategies to manage their dietary needs. Food experience was variable throughout their lifetime, with childhood experience having a sustained effect on adult eating behaviour. Weight gain, body image and dietary health implications are considerable concerns for patients. New CF transmembrane modulator treatments (CFTR modulators) are changing the dietary needs of this population. It is important that these issues are explored during dietetic consultations to identify barriers to dietary change.

Novel detection of specific bacterial quorum sensing molecules in saliva: Potential non-invasive biomarkers for pulmonary Pseudomonas aeruginosa in cystic fibrosis.

Pseudomonas aeruginosa produces specific signalling molecules, 2-alkyl-4-quinolones (AQs) that are detectable in the sputum of adults with cystic fibrosis (CF) and who have pulmonary infection with this opportunistic pathogen. This study aimed to determine whether AQs could be detected in saliva of patients with CF and known infection with Pseudomonas aeruginosa. Saliva and sputum samples were obtained from 89 adults with CF and analyzed using liquid chromatography-tandem mass spectrometry. AQs were detected in 39/89 (43.8%) saliva samples and 70/77(90.9%) sputum samples. Salivary AQs had a sensitivity of 50% (95%CI; 37.8; 62.2), specificity of 100% (95%CI; 47.8; 100), when compared to a molecular microbiological measure of P. aeruginosa in sputum as measured using polymerase chain reaction. Specific AQs produced by P. aeruginosa can be detected in the saliva and warrant investigation as potential non-invasive biomarkers of pulmonary P. aeruginosa.

2-Alkyl-4-quinolone quorum sensing molecules are biomarkers for culture-independent Pseudomonas aeruginosa burden in adults with cystic fibrosis.

Introduction. Pseudomonas aeruginosa produces quorum sensing signalling molecules including 2-alkyl-4-quinolones (AQs), which regulate virulence factor production in the cystic fibrosis (CF) airways.Hypothesis/Gap statement. Culture can lead to condition-dependent artefacts which may limit the potential insights and applications of AQs as minimally-invasive biomarkers of bacterial load.Aim. We aimed to use culture-independent methods to explore the correlations between AQ levels and live P. aeruginosa load in adults with CF.Methodology. Seventy-five sputum samples at clinical stability and 48 paired sputum samples obtained at the beginning and end of IV antibiotics for a pulmonary exacerbation in adults with CF were processed using a viable cell separation technique followed by quantitative P. aeruginosa polymerase chain reaction (qPCR). Live P. aeruginosa qPCR load was compared with the concentrations of three AQs (HHQ, NHQ and HQNO) detected in sputum, plasma and urine.Results. At clinical stability and the beginning of IV antibiotics for pulmonary exacerbation, HHQ, NHQ and HQNO measured in sputum, plasma and urine were consistently positively correlated with live P. aeruginosa qPCR load in sputum, compared to culture. Following systemic antibiotics live P. aeruginosa qPCR load decreased significantly (P<0.001) and was correlated with a reduction in plasma NHQ (plasma: r=0.463, P=0.003).Conclusion. In adults with CF, AQ concentrations correlated more strongly with live P. aeruginosa bacterial load measured by qPCR compared to traditional culture. Prospective studies are required to assess the potential of systemic AQs as biomarkers of P. aeruginosa bacterial burden.

Retinopathy and microalbuminuria are common microvascular complications in cystic fibrosis-related diabetes.

AIMS: To study the prevalence of microvascular complications and renal changes associated with cystic fibrosis-related diabetes (CFRD). METHODS: This retrospective cohort study was conducted at the West Midlands Adult Cystic Fibrosis centre, United Kingdom. Data regarding age, sex, microalbuminuria, retinopathy neuropathy, and biochemical results were collected for all people with CFRD who had an annual review from 1 January 2018 to 31 December 2018 at the centre. Descriptive statistics were analysed using STATAv15.1. RESULTS: A total of 189 patients were included, of which 56.6% were male and median age (interquartile range) was 33 (27-39) years; 79.4% (150/189) had their annual review in 2018. Those with a biochemically impaired renal function numbered 7.2% (13/180) and 22.7% (32/141) had microalbuminuria; 17.2% (10/58) had diabetes related retinopathy. No one in our cohort had diabetic ulcers; however, 10.3% (13/126) had absent foot pulses. CONCLUSION: We found a higher prevalence of microalbuminuria compared with retinopathy in a large cohort of cystic fibrosis adults. This study demonstrates the need for regular specialist follow-up to facilitate early identification of such complications and a long-term prospective cohort to understand underlying mechanisms.

Clinical significance of Pseudomonas aeruginosa 2-alkyl-4-quinolone quorum-sensing signal molecules for long-term outcomes in adults with cystic fibrosis.

Introduction. Pseudomonas aeruginosa is an important respiratory pathogen in cystic fibrosis (CF), which is associated with an accelerated decline in lung function, frequent pulmonary exacerbations and increased mortality. P. aeruginosa produces intercellular signalling molecules including 2-alkyl-4-quinolones (AQs), which regulate virulence-factor production and biofilm formation in the CF airways. Studies have shown that AQs are detectable in the sputum and plasma of adults with CF and chronic pulmonary P. aeruginosa.Aim. We tested the hypothesis that the presence of six AQs in plasma or sputum obtained from adults with CF was associated with long-term adverse clinical outcomes.Methodology. We analysed clinical data over an 8 year follow period for 90 people with CF who had previously provided samples for AQ analysis at clinical stability. The primary outcome was all cause mortality or lung transplantation. Secondary outcomes were the rate of lung-function decline and the number of intravenous (IV) antibiotic days for pulmonary exacerbations.Results. There was no statistical association between the presence of any of the six measured AQs and the primary outcomes or the secondary outcome of decline in lung function. One of the six AQs was associated with IV antibiotic usage. The presence of 2-nonyl-3-hydroxy-4(1 h)-quinolone (C9-PQS) in sputum was associated with an increase in the number of IV antibiotic days in the follow-up period (Mann-Whitney; P=0.011).Conclusion. Further investigation to confirm the hypothesis that C9-PQS may be associated with increased antibiotic usage for pulmonary exacerbations is warranted as AQ-dependent signalling is a potential future target for anti-virulence therapies.

Laboratory Diagnosis and Characterization of Fungal Disease in Patients with Cystic Fibrosis (CF): A Survey of Current UK Practice in a Cohort of Clinical Microbiology Laboratories.

There is much uncertainty as to how fungal disease is diagnosed and characterized in patients with cystic fibrosis (CF). A 19-question anonymous electronic questionnaire was developed and distributed to ascertain current practice in clinical microbiology laboratories providing a fungal laboratory service to CF centres in the UK. Analyses of responses identified the following: (1) current UK laboratory practice, in general, follows the current guidelines, but the scope and diversity of what is currently being delivered by laboratories far exceeds what is detailed in the guidelines; (2) there is a lack of standardization of fungal tests amongst laboratories, outside of the current guidelines; (3) both the UK CF Trust Laboratory Standards for Processing Microbiological Samples from People with Cystic Fibrosis and the US Cumulative Techniques and Procedures in Clinical Microbiology (Cumitech) Guidelines 43 Cystic Fibrosis Microbiology need to be updated to reflect both new methodological innovations, as well as better knowledge of fungal disease pathophysiology in CF; (4) there is a need for clinical medicine to decide upon a stratification strategy for the provision of new fungal assays that will add value to the physician in the optimal management of CF patients; (5) there is also a need to rationale what assays should be performed at local laboratory level and those which are best served at National Mycology Reference Laboratory level; and (6) further research is required in developing laboratory assays, which will help ascertain the clinical importance of 'old' fungal pathogens, as well as 'emerging' fungal pathogens.

British Lung Foundation/United Kingdom Primary Immunodeficiency Network Consensus Statement on the Definition, Diagnosis, and Management of Granulomatous-Lymphocytic Interstitial Lung Disease in Common Variable Immunodeficiency Disorders.

A proportion of people living with common variable immunodeficiency disorders develop granulomatous-lymphocytic interstitial lung disease (GLILD). We aimed to develop a consensus statement on the definition, diagnosis, and management of GLILD. All UK specialist centers were contacted and relevant physicians were invited to take part in a 3-round online Delphi process. Responses were graded as Strongly Agree, Tend to Agree, Neither Agree nor Disagree, Tend to Disagree, and Strongly Disagree, scored +1, +0.5, 0, -0.5, and -1, respectively. Agreement was defined as greater than or equal to 80% consensus. Scores are reported as mean ± SD. There was 100% agreement (score, 0.92 ± 0.19) for the following definition: "GLILD is a distinct clinico-radio-pathological ILD occurring in patients with [common variable immunodeficiency disorders], associated with a lymphocytic infiltrate and/or granuloma in the lung, and in whom other conditions have been considered and where possible excluded." There was consensus that the workup of suspected GLILD requires chest computed tomography (CT) (0.98 ± 0.01), lung function tests (eg, gas transfer, 0.94 ± 0.17), bronchoscopy to exclude infection (0.63 ± 0.50), and lung biopsy (0.58 ± 0.40). There was no consensus on whether expectant management following optimization of immunoglobulin therapy was acceptable: 67% agreed, 25% disagreed, score 0.38 ± 0.59; 90% agreed that when treatment was required, first-line treatment should be with corticosteroids alone (score, 0.55 ± 0.51).

A prospective pilot study of home monitoring in adults with cystic fibrosis (HOME-CF): protocol for a randomised controlled trial.

BACKGROUND: Home monitoring has the potential to detect early pulmonary exacerbations in people with cystic fibrosis (CF), with consequent improvements in health outcomes and healthcare associated costs. This study aims to assess the effects of home monitoring on hospital admissions, quality of life, antibiotic requirements, exacerbation frequency, lung function, nutritional outcomes, anxiety, depression, costs and health outcomes, as well as the qualitative effects on the patient experience. METHODS: This randomised controlled mixed-methods trial aims to recruit 100 adults with CF cared for in one large regional CF centre. Participants are randomly allocated 1:1 to the intervention group (twice-weekly home monitoring of symptoms measured by the Cystic Fibrosis Respiratory Symptom Diary - Chronic Respiratory Infection Symptom Score (CFRSD-CRISS) and Forced Expiratory Volume in one second (FEV1)) or a control group (routine clinical care) for the 12-month study period. Measurements are recorded at study visits at baseline, 3, 6, 9 and 12 months. Spirometry, body weight, co-morbidities, medications, hospital inpatient days, courses of antibiotics (oral and intravenous), pulmonary exacerbations (defined by the modified Fuchs criteria) are recorded at each study visit. Health status, capability and health economics are measured at each study visit by the Hospital Anxiety and Depression Scale (HADS), the ICEpop CAPability measure for Adults (ICECAP-A), EuroQol 5 dimensions (EQ-5D-5L) questionnaire and an adapted resource use questionnaire. The patient experience is assessed by semi-structured qualitative interviews at baseline and 12 months. DISCUSSION: Results from this study will help to determine the effect of home monitoring on inpatient bed days and quality of life in adults with CF, as well as other relevant health and health economic outcomes. TRIAL REGISTRATION: This study protocol is registered with Clinicaltrials.gov ( NCT02994706 ), date registered 16th July 2014.

Pseudomonas aeruginosa quorum sensing molecules correlate with clinical status in cystic fibrosis.

Pseudomonas aeruginosa produces quorum sensing signal molecules that are potential biomarkers for infection.A prospective study of 60 cystic fibrosis patients with chronic P. aeruginosa, who required intravenous antibiotics for pulmonary exacerbations, was undertaken. Clinical measurements and biological samples were obtained at the start and end of the treatment period. Additional data were available for 29 of these patients when they were clinically stable.Cross-sectionally, quorum sensing signal molecules were detectable in the sputum, plasma and urine of 86%, 75% and 83% patients, respectively. They were positively correlated between the three biofluids. Positive correlations were observed for most quorum sensing signal molecules in sputum, plasma and urine, with quantitative measures of pulmonary P. aeruginosa load at the start of a pulmonary exacerbation. Plasma concentrations of 2-nonyl-4-hydroxy-quinoline (NHQ) were significantly higher at the start of a pulmonary exacerbation compared to clinical stability (p<0.01). Following the administration of systemic antibiotics, plasma 2-heptyl-4-hydroxyquinoline (p=0.02) and NHQ concentrations (p<0.01) decreased significantly.In conclusion, quorum sensing signal molecules are detectable in cystic fibrosis patients with pulmonary P. aeruginosa infection and are positively correlated with quantitative measures of P. aeruginosa. NHQ correlates with clinical status and has potential as a novel biomarker for P. aeruginosa infection.

Physical activity in adults with cystic fibrosis receiving intravenous antibiotics in hospital and in the community.

INTRODUCTION: Intravenous antibiotic therapy (IVAT) for CF acute pulmonary exacerbations (APE) can be delivered in hospital or in the community. This study aimed to compare physical activity in CF patients receiving hospital and community-delivered IVAT, as well as other health outcomes. MATERIALS AND METHODS: This was a non-randomised parallel group prospective observational study. Hospitalised and community-treated CF adults receiving IVAT for APE were asked to wear ActiGraph® activity monitors, complete the habitual activity estimation scale (HAES), food diary, modified shuttle test (MST) and CFQ-R at the start and end of therapy. Nutritional and clinical outcomes were also compared between the cohorts. The primary outcomes was physical activity measured by the ActiGraph® activity monitors at the beginning and end of treatment in both cohorts. RESULTS: Physical activity (measured and self-reported) was no different between the cohorts, with both hospitalised and community-treated subjects being generally sedentary. Body weight increased significantly in the hospitalised cohort, whereas no difference was seen in the community-treated cohort. FEV1 % predicted and FVC % predicted increased in community-treated subjects, whereas only FVC % predicted increased in hospitalised subjects. CFQ-R respiratory domain increased to a greater extent in community-treated subjects. CONCLUSION: CF adults receiving IVAT for APE, both in hospital and in the community, are generally sedentary and we found no difference in physical activity between the two groups. These findings suggests the need to further promote physical activity in suitable patients during APE where considered appropriate.

Cross-sectional and longitudinal multilocus sequence typing of pseudomonas aeruginosa in cystic fibrosis sputum samples.

Multilocus sequence typing (MLST) is a genetic typing tool designed to provide information about the relatedness of isolates at the core genome level. The utility of MLST in regard to cystic fibrosis (CF)-related infection with Pseudomonas aeruginosa is unknown. The molecular clock speed of the MLST genes was studied using 219 colonies isolated longitudinally from 49 patients with CF. A cross-sectional study examining 27 to 46 colonies per sputum sample for samples from 16 patients was also undertaken. The molecular clock speed was estimated to be 2.05 x 10(-5) (upper 95% confidence limit) or 4.75 x 10(-6) (50% confidence limit) point mutations per nucleotide per year. In the cross-sectional study, 50% of patients were infected with more than one sequence type. There was evidence of point mutations, recombination events, and coinfection with epidemic and unique strains. A clonal complex that was highly genetically distinct from the rest of the P. aeruginosa population was identified. The MLST scheme uses genes with an appropriate clock speed and provides useful information about the genetic variation of P. aeruginosa within and between patients with CF.

Association between hypermutator phenotype, clinical variables, mucoid phenotype, and antimicrobial resistance in Pseudomonas aeruginosa.

The presence of hypermutator Pseudomonas aeruginosa was associated with poorer lung function in patients at the Adult West Midlands CF Unit. Mucoid isolates were more likely to be hypermutators. The presence of resistant mutant subpopulations was associated with hypermutator phenotype but was not good enough to be used as a test for this phenotype.