Diagnosing Cystic Fibrosis in Adults.

Diagnosing cystic fibrosis (CF) in adulthood is not a rare occurrence for CF centers despite the popular belief that the diagnosis is achieved almost universally in childhood by means of newborn screening or early clinical presentation. The purpose of this review article is to highlight specific considerations of adult diagnosis of CF. Obtaining a diagnosis of CF at any age is exceptionally important to ensure optimal treatment, monitoring, and support. In the new era of more personalized treatment with the advent of transformative therapies targeting the underlying protein defect, accurate diagnosis is of increasing importance. This review highlights the diagnostic algorithm leading to a new diagnosis of CF in adults. The diagnosis is usually confirmed in the presence of a compatible clinical presentation, evidence of cystic fibrosis transmembrane conductance regulator (CFTR) protein dysfunction, and/or identification of variants in the CFTR gene believed to alter protein function. Achieving the diagnosis, however, is not always straightforward as CFTR protein function exists on a continuum with different organs displaying varying sensitivity to diminution in function. We highlight the current knowledge regarding the epidemiology of CF diagnosed in adults and outline the various clinical presentations, including pulmonary and extrapulmonary, which are more common in this population. We expand on the stepwise testing procedures that lead to diagnosis, paying particular attention to additional levels of testing which may be required to achieve an accurate diagnosis. There continues to be an important need for both pulmonary and other specialists to be aware of the potential for later presentation of CF, as the improvements in treatment over decades have had large positive impacts on prognosis for people with this condition.

Mediation of the total effect of cystic fibrosis-related diabetes on mortality: A UK Cystic Fibrosis Registry cohort study.

AIM: To investigate whether the effect of cystic fibrosis-related diabetes (CFRD) on the composite outcome of mortality or transplant could act through lung function, pulmonary exacerbations and/or nutritional status. METHODS: A retrospective cohort of adult cystic fibrosis (CF) patients who had not been diagnosed with CFRD were identified from the UK Cystic Fibrosis Registry (n = 2750). Rate of death or transplant was compared between patients who did and did not develop CFRD (with insulin use) during follow-up using Poisson regression, separately by sex. Causal mediation methods were used to investigate whether lung function, pulmonary exacerbations and nutritional status lie on the causal pathway between insulin-treated CFRD and mortality/transplant. RESULTS: At all ages, the mortality/transplant rate was higher in both men and women diagnosed with CFRD. Pulmonary exacerbations were the strongest mediator of the effect of CFRD on mortality/transplant, with an estimated 15% [95% CI: 7%, 28%] of the effect at 2 years post-CFRD diagnosis attributed to exacerbations, growing to 24% [95% CI: 9%, 46%] at 4 years post-diagnosis. Neither lung function nor nutritional status were found to be significant mediators of this effect. Estimates were similar but with wider confidence intervals in a cohort that additionally included people with CFRD but not using insulin. CONCLUSION: There is evidence that pulmonary exacerbations mediate the effect of CFRD on mortality but, as they are estimated to mediate less than one-quarter of the total effect, the mechanism through which CFRD influences survival may involve other factors.

Assessing the health risk of living near composting facilities on lung health, fungal and bacterial disease in cystic fibrosis: a UK CF Registry study.

AIM: To explore the health risk of living near permitted composting sites (PCSs) on disease severity in children and adults with cystic fibrosis (CF) across the UK.  METHODS: A semi-individual cross-sectional study was used to examine the risk of disease severity in people with CF (pwCF) within and beyond 4 km of PCSs in the UK in 2016. All pwCF registered in the UK CF Registry were eligible for this study. Linear and Poisson regressions, adjusted for age, gender, genotype, BMI, Pseudomonas aeruginosa and deprivation, were used to quantify associations between distance to a PCS and percent predicted forced expiratory volume in one second (ppFEV1), pulmonary exacerbations (#IVdays), and fungal and bacterial infections. RESULTS: The mean age of the 9,361 pwCF (3,931 children and 5,430 adults) studied was 20.1 (SD = 14.1) years; 53.3% were male; and 49.2% were homozygous F508del. Over 10% of pwCF (n = 1,015) lived within 4 km of a PCS. We found no statistically significant difference in ppFEV1 and #IVdays/year in children. However, in adults, ppFEV1 was -1.07% lower (95% confidence interval (CI): -2.29%, 0.16%) and #IVdays/year were 1.02 day higher (95%CI: 1.01, 1.04) within 4 km of a PCS. Furthermore, there were statistically significant differences in mean ppFEV1 in CF adults with Aspergillus fumigatus (58.2.% vs 62.0%, p = 0.005) and Candida spp. (56.9% vs 59.9%, p = 0.029) residing within 4 km of a PCS. No associations were identified for allergic bronchopulmonary aspergillosis, P. aeruginosa or Staphylococcus aureus. CONCLUSIONS: This novel national study provides evidence that adults with CF living near a PCS may experience small reductions in lung function, an increased risk of pulmonary exacerbations, and more frequent fungal infections. If confirmed by studies using refined exposure assessment methods accounting for bioaerosol dispersion, these results could have important implications for the living environment of pwCF.

New strategies of physical activity assessment in cystic fibrosis: a pilot study.

BACKGROUND: Regular physical activity (PA) is a valued part of cystic fibrosis (CF) care. Although the accelerometer, SenseWear Armband (SWA), accurately measures habitual PA in CF, it is mostly used for research purposes. For the first time, we analyzed different methods of measuring PA in daily life by the use of smartphones and other electronic devices such as smartwatch and Fitbit. METHODS: Twenty-four stable adults with CF (mean age 37.5 ± 11.5SD yrs.; FEV1 58 ± 19% predicted, BMI 22.9 ± 3.2) were studied. Daily PA was monitored for seven consecutive days. All patients wore the accelerometer SWA and at the same time they monitored PA with the electronic device they used routinely. They were allocated into one of four arms according to their device: Smartwatch, Fitbit, Android smartphones and iOS smartphones. PA related measurements included: duration of PA, energy expenditure, number of steps. RESULTS: There was a good agreement between SWA and Fitbit for number of steps (p = 0.605) and energy expenditure (p = 0.143). iOS smartphones were similar to SWA in monitoring the number of steps (p = 0.911). Significant differences were found between SWA and both Smartwatch and Android smartphones. CONCLUSIONS: Fitbit and iOS smartphones seem to be a valuable approach to monitor daily PA. They provide a good performance to measure step number compared to SWA.

Airway persistence by the emerging multi-azole-resistant Rasamsonia argillacea complex in cystic fibrosis.

Infections caused by Rasamsonia argillacea complex have been reported in various clinical settings. Cystic fibrosis (CF) is one of the main underlying conditions. An observational cohort study of CF patients with Rasamsonia in respiratory samples was conducted. Eight isolates from 6 patients were identified as R. argillacea complex and tested for antifungal susceptibility. All isolates had high MICs to voriconazole and posaconazole and low MECs to echinocandins. Four patients experienced lung function decline in the year preceding first Rasamsonia isolation. This continued in the year following first isolation in 3 out of 4 cases. Antifungal therapy was initiated in 2 patients, to which only one exhibited a clinical response. Three out of 6 patients died within 3 years of isolating Rasamsonia. Genotyping suggests that similar genotypes of Rasamsonia can persist in CF airways. Consistent with other fungi in CF, the clinical impact of airway colonisation by Rasamsonia is variable. In certain patients, Rasamsonia may be able to drive clinical decline. In others, though a clear impact on lung function may be difficult to determine, the appearance of Rasamsonia acts as a marker of disease severity. In others it does not appear to have an obvious clinical impact on disease progression.

Is daily physical activity affected by dynamic hyperinflation in adults with cystic fibrosis?

BACKGROUND: The aim of this study was to investigate the relationship between dynamic hyperinflation and daily physical activity (DPA) in adults with cystic fibrosis (CF). METHODS: Thirty-four clinically stable CF were studied. All patients undertook incremental cardiopulmonary exercise testing (CPET). CPET-related measurements included: oxygen uptake (V'O2), carbon dioxide production (V'CO2), ventilatory profile, work rate (W), inspiratory capacity (IC), end-expiratory lung volume (EELV). PA was assessed using the accelerometer SenseWear Pro3 Armband. RESULTS: Exercise tolerance was reduced in most of patients and the mean V'O2,peak value was 75.2% of predicted (28.5 ± 4.8 ml/min/kg). Seventy % of patients responded to CPET with dynamic hyperinflation. Higher incidence of dynamic hyperinflation was found in CF males compared to CF females (p = 0.026). Patients who developed dynamic hyperinflation during CPET had higher vigorous PA (p = 0.01) and more total energy expenditure (p = 0.006) than patients who did not. EELVΔ was related to activities requiring vigorous intensity and total energy expenditure (R = 0.46, p = 0.001; R = 0.57, p <  0.001). CONCLUSIONS: In adults with CF and mild to moderate lung impairment, DPA might not be limited by dynamic hyperinflation.

Phenotypic variability of R117H-CFTR expression within monozygotic twins.

Whilst cystic fibrosis is a monogenic condition, variation in phenotype exists for the same CFTR genotype, which is influenced by multiple genetic and non-genetic (environmental) factors. The R117H-CFTR mutation has variability directly relating to in cis poly-thymidine alleles, producing a differing spectrum of disease. This paper provides evidence of extreme phenotype variability - including fertility status - in the context of male monogenetic twins, discussing mechanisms and highlighting the diagnostic and treatment challenges.

Cystic Fibrosis Papers of the Year, 2013-2014.

Studies published in the last year in the field of cystic fibrosis have provided more data on the safety and efficacy of a number of therapies, including mutation-specific drugs. There have also been a number of publications on monitoring of early lung disease including the use of lung clearance index and magnetic resonance scanning. Evidence suggests early lung changes may remain relatively static over the first year of life. There are important outcome differences across national patient registries and there is also the increasing recognition of psychological illnesses and possible drug interactions as treatment becomes more complicated and survival improves.

Aspergillus and cystic fibrosis: old disease - new classifications.

PURPOSE OF REVIEW: Aspergillus pulmonary infection has traditionally been recognized as a clinical spectrum of increasing pathogenicity, encompassing saprophytic airways colonization historically regarded of doubtful clinical significance, to allergic bronchopulmonary aspergillosis, chronic cavitatory and life-threatening invasive disease in the immunocompromised host. Whilst the latter two categories are rarely encountered in cystic fibrosis (CF), there is recognition of an extending spectrum of disease yet to be reflected in consensus management guidelines. The purpose of this review is to provide an up-to-date overview of this extending spectrum, with a focus on disease categories and their clinical significance. RECENT FINDINGS: Conflicting evidence regarding the clinical significance of Aspergillus colonization and sensitization in CF, alongside the emergence of a novel disease category 'Aspergillus bronchitis', has led to proposals for the reclassification of Aspergillus disease. In addition, lack of standardization and poor sensitivity of culture-dependent mycology techniques renders clinical and epidemiological interpretation of these isolates challenging. SUMMARY: The role of Aspergillus in the absence of established CF-allergic bronchopulmonary aspergillosis remains unclear. The following review discusses new approaches proposed to categorise the extended spectrum of CF Aspergillus disease, highlighting the need for enhanced microbiological investigation and serological monitoring of patients in light of evidence which differentiates colonization from categories of greater pathogenic potential.

How representative are clinical trial cohorts of the general CF population? Implications for trial planning.

Understanding the number of patients eligible to participate in research is important to design protocols and define research priorities. We reviewed the records of all patients with CF, age 12+, who receive care at our centre. We assessed their eligibility for trial participation based on common trial inclusion/exclusion criteria. 643 patients were included in the analysis, 31 were modulator ineligible(MI). Only 198(31 %) of the total cohort and 7(23 %) of the MI cohort were eligible for participation based on the hypothetical criteria. The most common reason for ineligibility was ppFEV1 ≥90 % followed by clinical instability, complex comorbidity and anticipated inability to adhere to the protocol. We suggest this would be a useful exercise for centres planning to either participate in, or refer subjects into, upcoming trials to undertake for their own cohort. We also make suggestions for protocol designs that optimise the number of patients who are eligible to participate.

Inhaled antimicrobial prescribing for Pseudomonas aeruginosa infections in Europe.

BACKGROUND: Prescribers have an increasing range of inhaled antimicrobial formulations to choose from when prescribing both eradication and chronic suppression regimens in cystic fibrosis (CF). This study aimed to investigate the decision-making process behind prescribing of inhaled antimicrobials for Pseudomonas aeruginosa infections. METHODS: A questionnaire was developed using Microsoft Forms and then forwarded to 57 Principal Investigators (PIs), at each of the CF centres within the European Cystic Fibrosis Society-Clinical Trials Network (ECFS-CTN). Data collection occurred between November 2021 and February 2022. RESULTS: The response rate was 90 % (n = 51/57 PIs), with at least 50 % of CF centers in each of the 17 countries represented in the ECFS-CTN. Physicians used a median of eight factors in their decision-making process with delivery formulations (92.2 %), adherence history (84.3 %), and antibiotic side-effect profile (76.5 %) often selected. Nebulised tobramycin or colistin were frequently selected as the inhaled antimicrobial in first-line eradication (n = 45, 88.2 %) and chronic suppression regimens (n = 42, 82.4 %). Combination regimens were more often chosen in eradication (first-line: n = 35, 68.6 %, second-line: n = 34, 66.7 %) and later chronic suppression regimens (third-line: n = 27, 52.9 %) than monotherapy. For pwCF also prescribed CFTR modulator therapies, most PIs did not alter inhaled antimicrobial regimens (n = 40, 78.4 %), with few pwCF (n = 18, 35.3 %) or PIs (n = 10, 19.6 %) deciding to stop inhaled antimicrobials. CONCLUSIONS: The inhaled antimicrobial prescribing decision-making process is multifactorial. Nebulised tobramycin or colistin are often used in initial eradication and chronic suppression regimens. To date, CFTR modulator therapy has had a limited impact on the prescribing of inhaled antimicrobial regimens.

The destructive combination of Scediosporium apiosperum lung disease and exuberant inflammation in cystic fibrosis.

This paper describes a patient whose decline over two years was precipitous, from an active independent life with lung function (FEV1) above 50% to requiring transplantation. The main pathogen on sputum culture throughout that period was Scediosporium apiosperum. The epidemiology pathogenicity and treatment of this fungal pathogen are discussed.

Cystic fibrosis modulator therapy can reverse cystic bronchiectasis.

Bronchiectasis is often considered progressive and irreversible, so cases of regression or reversal are an important step in understanding the underlying pathophysiological mechanisms. Cystic fibrosis, (CF) caused by pathogenic variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene has been a success story in personalized medicine. The recent development of CFTR modulator therapies has revolutionized care. Dramatic improvements in lung function, sputum production, daytime functioning, and quality of life are seen within weeks. However, the effect of long-term exposure to elexacaftor + tezacaftor + ivacaftor (ETI) on the structural abnormalities is at present unknown. This case series outlines three adults with CF who have demonstrated progressive improvement in the cylindrical, varicose and importantly cystic changes of bronchiectasis with prolonged ETI treatment. This raises the exciting question of reversibility of bronchiectasis as well as the mechanisms involved in the maintenance and progression of bronchiectasis as it relates to CF.

VOCAL: An observational study of ivacaftor for people with cystic fibrosis and selected non-G551D-CFTR gating mutations.

BACKGROUND: VOCAL was an observational study of the effect of long-term ivacaftor on real-world clinical outcomes and healthcare resource utilization (HCRU) in people with cystic fibrosis (pwCF) in Italy, the Netherlands, and the UK. METHODS: pwCF aged ≥6 years with non-G551D-CFTR gating mutations were eligible. Prospective data were collected up to 48 months after enrollment; retrospective data were collected to ensure that 12 months of pre-ivacaftor data were available. Endpoints included absolute change from baseline in percent predicted forced expiratory volume in 1 second (ppFEV1) and measures of nutritional status. Pulmonary exacerbation (PEx) rates, HCRU, and respiratory microbiology during ivacaftor treatment were compared with data from the 12-month period before initiation. RESULTS: Seventy-three eligible pwCF were enrolled and received ivacaftor; 65 (89.0%) completed the study (48 [65.8%] completed ≥48 months of ivacaftor). During the first 6 months of ivacaftor, ppFEV1, body mass index (BMI), and BMI-for-age z-score showed least-squares mean absolute improvements of 10.8 percentage points, 0.79 kg/m2, and 0.54, respectively; improvements were maintained through 48 months. Rates of PEx, antibiotic use due to PEx, and hospitalization decreased by >50% during ivacaftor treatment compared with before ivacaftor. The number of respiratory cultures and sputum was lower post-ivacaftor, as was the percentage of pwCF with positive respiratory cultures for 3 of 9 pathogens evaluated (Pseudomonas aeruginosa, Aspergillus fumigatus, Stenotrophomonas maltophilia). Reported safety results were consistent with CF and ivacaftor's known safety profile. CONCLUSIONS: These results demonstrate the positive long-term effectiveness of ivacaftor on clinical outcomes and HCRU in pwCF with non-G551D-CFTR gating mutations in real-world settings.

An invisible threat? Aspergillus positive cultures and co-infecting bacteria in airway samples.

BACKGROUND: Aspergillus fumigatus (Af) infection is associated with poor lung health in chronic suppurative lung diseases but often goes undetected. We hypothesised that inhibition of Af growth by Pseudomonas aeruginosa (Pa) increases the frequency of false-negative Af culture in co-infected people. Using a substantial group of cystic fibrosis (CF) airway samples, we assessed the relationship between Af and bacterial pathogens, additionally comparing fungal culture with next-generation sequencing. METHODS: Frequency of co-culture was assessed for 44,554 sputum/BAL cultures, from 1,367 CF patients between the years 2010-2020. In a subgroup, Internal Transcribed Spacer-2 (ITS2) fungal sequencing was used to determine sequencing-positive, culture-negative (S+/C-) rates. RESULTS: Pa+ samples were nearly 40% less likely (P<0.0001) than Pa- samples to culture Af, an effect that was also seen with some other Gram-negative isolates. This impact varied with Pa density and appeared to be moderated by Staphylococcus aureus co-infection. Sequencing identified Af-S+/C- for 40.1% of tested sputa. Samples with Pa had higher rates of Af-S+/C- (49.3%) than those without (35.7%; RR 1.38 [1.02-1.93], P<0.05). Af-S+/C- rate was not changed by other common bacterial infections. Pa did not affect the S+/C- rates of Candida, Exophiala or Scedosporium. CONCLUSIONS: Pa/ Af co-positive cultures are less common than expected in CF. Our findings suggest an Af-positive culture is less likely in the presence of Pa. Interpretation of negative cultures should be cautious, particularly in Pa-positive samples, and a companion molecular diagnostic could be useful. Further work investigating mechanisms, alternative detection techniques and other chronic suppurative lung diseases is needed.

Standards for the care of people with cystic fibrosis (CF): A timely and accurate diagnosis.

There is considerable activity with respect to diagnosis in the field of cystic fibrosis (CF). This relates primarily to developments in newborn bloodspot screening (NBS), more extensive gene analysis and improved characterisation of CFTR-related disorder (CFTR-RD). This is particularly pertinent with respect to accessibility to variant-specific therapy (VST), a transformational intervention for people with CF with eligible CFTR gene variants. This advance reinforces the need for a timely and accurate diagnosis. In the future, there is potential for trials to assess effectiveness of variant-specific therapy for CFTR-RD. The guidance in this paper reaffirms previous standards, clarifies a number of issues, and integrates emerging evidence. Timely and accurate diagnosis has never been more important for people with CF.

Incidence and risk factors of cancer in individuals with cystic fibrosis in the UK; a case-control study.

To assess cancer incidence in the UK cystic fibrosis (CF) population and determine the associated risk factors, we undertook a nested case-control study of patients with CF, registered with the UK CF Registry. Each case with a first reported cancer between 1999 and 2017 was matched with up to 4 controls: by age (±2-years) and year of cancer diagnosis. Conditional logistic regressions were adjusted for sex, lung function (FEV1%), CF related diabetes (CFRD), F508del status, transplant status, DIOS, gastro-oesophageal reflux disease, meconium ileus, Pseudomonas aeruginosa infection, pancreatic insufficiency, proton pump inhibitor (PPI) use, IV antibiotic days and BMI. Results: From 12,886 registered patients, 146 (1.1%) cases of malignancy were identified with 14.3% of cases occurring post solid organ transplant. Site of primary cancer was available for 98 patients: 22% were gastro-intestinal in origin (77% lower, 23% upper GI), 13% skin, 13% breast and 11% lymphomas/leukaemia. In univariable analysis, transplantation increased the odds of reporting any cancer by 2.46 times (95%CI: 1.3-4.6). CFRD also increased the odds of reporting any cancer (OR 2.35; CI: 1.37-4.0) and PPI use (OR 2.0; CI 1.28-3.19). In the multivariable models significant associations with CFRD and transplant remained, while PA infection, PPI use and being overweight showed increased, but statistically insignificant risks. The incidence of GI cancer was strongly associated with CFRD (OR=4.04; 1.47-11.1). Conclusions: We observed a high incidence of lower GI cancers in our cohort which was significantly affected by the presence of CFRD. Screening for gastrointestinal cancers could benefit patients at higher risk.

Treatment Preference Among People With Cystic Fibrosis: The Importance of Reducing Treatment Burden.

BACKGROUND: There is a growing consensus that the perspective of the patient should be considered in the evaluation of novel interventions. RESEARCH QUESTION: What treatment outcomes matter to people with cystic fibrosis (CF), and what trade-offs would they make to realize these outcomes? STUDY DESIGN AND METHODS: Adults attending a specialist CF center were invited to complete an online discrete choice experiment (DCE). The DCE required participants to evaluate hypothetical CF treatment profiles, defined by impact on lung function, pulmonary exacerbations, abdominal symptoms, life expectancy, quality of life, inhaled medicine usage, and physiotherapy requirement. Choice data were analyzed, using multinomial logit and latent class models. RESULTS: One hundred and three people with CF completed the survey (median age, 35 years; range, 18-76 years); 52% were female; mean FEV1 % predicted, 69% [SD, 22%]). On average, an improvement in life expectancy by 10 years or more had the greatest impact on treatment preference, followed by a 15% increase in lung function. However, it was shown that people would trade substantial reductions in these key outcomes to reduce treatment time or burden. Preference profiles were not uniform across the sample: three distinct subgroups were identified, each placing markedly different importance on the relative importance of both life expectancy and lung function compared with other attributes. INTERPRETATION: The relative importance of treatment burden to people with CF, compared with life expectancy and lung function, suggests it should be routinely captured in clinical trials as an important secondary outcome measure. When considering the patient perspective, it is important that decision-makers recognize that the values of people with CF are not homogeneous.