Considerations for the use of inhaled antibiotics for Pseudomonas aeruginosa in people with cystic fibrosis receiving CFTR modulator therapy

The major cause of mortality in people with cystic fibrosis (pwCF) is progressive lung disease characterised by acute and chronic infections, the accumulation of mucus, airway inflammation, structural damage and pulmonary exacerbations. The prevalence of Pseudomonas aeruginosa rises rapidly in the teenage years, and this organism is the most common cause of chronic lung infection in adults with cystic fibrosis (CF). It is associated with an accelerated decline in lung function and premature death. New P. aeruginosa infections are treated with antibiotics to eradicate the organism, while chronic infections require long-term inhaled antibiotic therapy. The prevalence of P. aeruginosa infections has decreased in CF registries since the introduction of CF transmembrane conductance regulator modulators (CFTRm), but clinical observations suggest that chronic P. aeruginosa infections usually persist in patients receiving CFTRm. This indicates that pwCF may still need inhaled antibiotics in the CFTRm era to maintain long-term control of P. aeruginosa infections. Here, we provide an overview of the changing perceptions of P. aeruginosa infection management, including considerations on detection and treatment, the therapy burden associated with inhaled antibiotics and the potential effects of CFTRm on the lung microbiome. We conclude that updated guidance is required on the diagnosis and management of P. aeruginosa infection. In particular, we highlight a need for prospective studies to evaluate the consequences of stopping inhaled antibiotic therapy in pwCF who have chronic P. aeruginosa infection and are receiving CFTRm. This will help inform new guidelines on the use of antibiotics alongside CFTRm.

Microbiology of cystic fibrosis persons not chronically infected with P. aeruginosa: A quasi-experimental study on two different upper airways' sampling methods

Background

The upper airways of cystic fibrosis (CF) persons are an evolutionary niche where genetically adapted bacterial strains are selected for lung infection. The microbiological studies conducted up to now on the upper airways are not easily comparable.

Methods

Using classical culture methods, we simultaneously studied the microbiological status of upper and lower airways in persons not chronically infected with P. aeruginosa. Each person had a single upper airways sampling and a concomitant lower airways sampling. Lower airways sampling was performed by oropharyngeal swab or sputum collection. Using a quasi-experimental design of study, we evaluated the performance of 2 different upper airways' sampling methods, nasal lavage according to method described by Mainz or nasal lavage with a rhino-set. Pain was measured with appropriate scales.

Results

A total of 194 persons were enrolled in this study. Pathogenic flora was found in 128 (6.6%) of 194 upper airways samples and in 164 (84.6%) lower airways samples. A statistically significant difference between the upper airways and the lower airways was found in the isolation of S. aureus and non-fermenter gram negatives. Nasal lavage according to Mainz resulted in the isolation of more non-fermenter gramnegatives than the rhino-set (p < 0.05). No differences were found in the pain caused bythe two methods.

Conclusions

In our study population, cultures of the upper airway and lower airway differ in CF persons. In people sampled with nasal lavage according to Mainz more non-fermenter gram negatives were detected than with rhino-set. The two sampling methods were comparable with regard to the caused pain, nasal lavage according to Mainz method being quicker to perform.

Risk of CFTR-related disorders and cystic fibrosis in an Italian cohort of CRMS/CFSPID subjects in preschool and school age

The identification of cystic fibrosis screening-positive, inconclusive diagnosis (CFSPID) in infants is a controversial outcome of newborn screening for cystic fibrosis (CF). Today, despite improvements in the knowledge of CFSPID and the description of several cohorts, little data are available on cohorts with a follow-up period of more than 6 years. In this study, we report the outcomes of an Italian cohort of CFSPID individuals with CFSPID or formerly CFTR-related disorders (CFTR-RD) (CFSPID > CFTR-RD) or diagnosed with CF (CFSPID > CF). This was an observational and multicentre Italian study collecting clinical data on CFSPID born between the period January 1, 2011, and December 13, 2019. A total of 268 participants were included: 243 with persistent CFSPID, 7 with CFSPID > CFTR-RD, and 18 with CFSPID > CF. The trend of sweat chloride (SC) values, percentage of definitive diagnoses, lung function in school-aged children, and development of CF-related complications were evaluated. At the end of the observation period, almost 80% of the individuals with CFSPID did not have a conclusive diagnosis. A total of 29 children (10.8%) transitioned to a diagnosis of CF for pathological SC values (≥ 60 mmol/L) or multi-organ involvement, and 18 (6.7%) to CFTR-RD. Children who were followed up for > 6 years (median age, 7.5 years; range, 6.04-10.5) had normal lung function and were pancreatic sufficient, and the evolution in CF was only present in two cases.

CONCLUSION

Most Italian preschool and school-aged children with CFSPID did not have a conclusive diagnosis, and progression to CF was unlikely in children > 6 years of age. An annual follow-up could be indicated to identify early evolution in clinical features consistent with a CFTR-RD.

WHAT IS KNOWN

• Cystic Fibrosis newborn screening identifies also subjects with an inconclusive diagnosis (CFSPID). • Over time a variable percentage of CFSPIDs will be diagnosed as CF. • Little data is available on CFSPIDs with a follow-up period of more than six years.

WHAT IS NEW

• 80% of Italian preschool and school-age CFSPIDs not have a conclusive diagnosis. • Italian preschool and school-age CFSPIDs have normal lung function and are pancreatic sufficient. • Annual follow-up after 6 years is recommended in CFSPID with abnormal LCI2.5 or with a CF-causing variant in trans with a VVCC.

Standards for the care of people with cystic fibrosis (CF); recognising and addressing CF health issues

This is the third in a series of four papers updating the European Cystic Fibrosis Society (ECFS) standards for the care of people with CF. This paper focuses on recognising and addressing CF health issues. The guidance was produced with wide stakeholder engagement, including people from the CF community, using an evidence-based framework. Authors contributed sections, and summary statements which were reviewed by a Delphi consultation. Monitoring and treating airway infection, inflammation and pulmonary exacerbations remains important, despite the widespread availability of CFTR modulators and their accompanying health improvements. Extrapulmonary CF-specific health issues persist, such as diabetes, liver disease, bone disease, stones and other renal issues, and intestinal obstruction. These health issues require multidisciplinary care with input from the relevant specialists. Cancer is more common in people with CF compared to the general population, and requires regular screening. The CF life journey requires mental and emotional adaptation to psychosocial and physical challenges, with support from the CF team and the CF psychologist. This is particularly important when life gets challenging, with disease progression requiring increased treatments, breathing support and potentially transplantation. Planning for end of life remains a necessary aspect of care and should be discussed openly, honestly, with sensitivity and compassion for the person with CF and their family. CF teams should proactively recognise and address CF-specific health issues, and support mental and emotional wellbeing while accompanying people with CF and their families on their life journey.

One year of treatment with elexacaftor/tezacaftor/ivacaftor in patients with cystic fibrosis homozygous for the F508del mutation causes a significant increase in liver biochemical indexes

Introduction: Modulators of cystic fibrosis transmembrane conductance regulator mutated protein significantly improved the outcome of patients with cystic fibrosis (CF). We describe 63 patients who were independently followed up in two CF regional centers (i.e., Campania and Tuscany regions). Methods: All patients were homozygous for the F508del mutation and were treated with lumacaftor/ivacaftor (LI) for 3 years, followed by 1 year of treatment with elexacaftor/tezacaftor/ivacaftor (ETI). We studied the biochemical parameters of liver damage and cholesterol metabolism. Results: Beyond the improvement of BMI and lung function with LI treatment and even more with ETI, we found that the 3 years of LI treatment significantly improved liver function parameters (total and conjugated bilirubin, ALT, AP, and GGT), while the subsequent ETI treatment caused a significant increase of such parameters. Discussion: We confirm that treatment with LI does not correct hypocholesterolemia, whereas treatment with ETI significantly increases serum cholesterol. Such an increase is likely due to enhanced de novo biosynthesis, as indicated by the significant increase in serum lathosterol, and it is likely that the subsequent liver cholesterol accumulation may contribute to triggering inflammation and worsening liver biochemical indexes. The increase in serum bilirubin and ALT that we observed in approximately 94% and 84% of patients treated with ETI, respectively, suggests further investigation of the impact of ETI therapy on liver function indexes.

The impact of elexacaftor/tezacaftor/ivacaftor therapy on the pulmonary management of adults with cystic fibrosis: An expert-based Delphi consensus

BACKGROUND

The advent of elexacaftor/tezacaftor/ivacaftor (ETI) resulted in unprecedented clinical benefits for eligible adults with CF. As a result, the question of whether chronic treatments can be safely stopped or adapted to this new situation has become a matter of great interest. Our objective was to derive a consensus among Italian experts on the impact of ETI on the current clinical management of CF lung disease.

METHODS

From December 2021 to April 2022 a panel of Italian experts endorsed by the national CF scientific society derived and graded a set of statements on the pulmonary management of adults with cystic fibrosis through a modified Delphi methodology.

RESULTS

The panel produced 13 statements exploring possible modifications in the fields of inhaled antibiotics and mucoactives; airway clearance and physical activity; chronic macrolides and bronchodilators; and lung transplant referral. The areas that the experts considered most urgent to explore were the impact of ETI on the role of inhaled antibiotics and lung transplant.

CONCLUSIONS

The list of priorities that emerged from this study could be useful to guide and inform clinical research on the most urgent area of impact of ETI on CF lung disease and its clinical management.

Cystic fibrosis and CFTR-related disorder with electrolyte imbalance at diagnosis: clinical features and outcome in an Italian cohort

There is limited information available on the clinical data, sweat test trends, and outcomes of individuals with cystic fibrosis (CF) who present with an isolated episode of hypoelectrolytemia with metabolic alkalosis (HMA). This study describes a cohort of Italian individuals with HMA as presenting symptom. The study is a retrospective multicenter analysis of individuals who presented with HMA as an initial symptom and was followed at 8 Italian CF Centers, from March 1988 to March 2022. Demographic, clinical, microbiological, biochemical, and genetic data were extracted from local health records. Ninety-three individuals were enrolled in the study. At first evaluation, 82 (88.2%) were diagnosed with CF, and 11 received a CFTR-Related Disorder (CFTR-RD) diagnostic label. Twenty-three (85.1%) out of the 27 subjects who underwent CF neonatal screening (NBS) resulted falsely negative. After a mean observational period of 11.5 years, most of subjects had a mild pulmonary phenotype, pancreatic sufficiency, and rarely CF-related complications. Four CFTR-RD changed to a CF diagnosis during the study period, resulting in 86 (92.4%) subjects classified as CF.

CONCLUSIONS

 Most CF patients presenting with isolated HMA have a mild course of disease and rarely CF-related complications.

WHAT IS KNOWN

• Isolated episode of hypoelectrolytemia with metabolic alkalosis is a well-known onset symptom of Cystic Fibrosis in infancy. • There is limited information available on the clinical data and outcomes of individuals with Cystic Fibrosis who present with electrolyte imbalance at diagnosis.

WHAT IS NEW

• Most patients with Cystic Fibrosis presenting with isolated hypoelectrolytemia and metabolic alkalosis have a mild course of disease and rarely CF-related complications. • Electrolyte imbalance at diagnosis of Cystic Fibrosis is a common symptom in children not screened for CF at birth, or in those who received a false negative result from newborn screening.

Monitoring of ECFS quality standards for the clinical management of adults with cystic fibrosis

BACKGROUND

Although cystic fibrosis (CF) standards of care have been produced and regularly updated, they are not specifically targeting at the adult population. The ECFS Standards of Care Project established an international task force of experts to identify quality standards for adults with CF and assess their adherence.

METHODS

This study was composed of two phases. In the first one, a task force of international experts derived from published guidelines and graded ten quality standards for adult CF care using a modified Delphi methodology. In the second phase, an international audit was conducted among adult CF centers to retrospectively validate the quality statements and monitor adherence.

RESULTS

The task force identified 10 quality standards specific to the care of adults with CF, mainly based on the 2018 ECFS standards of care. 14 adult CF centers participated in the audit, which showed that most quality standards for the management of CF in adults are met across Europe. Heterogeneity in adherence to standards was found across centers according to geographical setting and centers' characteristics.

CONCLUSIONS

The identification of quality standards is a valuable resource for the standardization and monitoring of care delivery across centers taking care of adults with CF.

Comparison between Gibson-Cooke and Macroduct Methods in the Cystic Fibrosis Neonatal Screening Program and in Subjects Who Are Cystic Fibrosis Screen-Positive with an Inconclusive Diagnosis

The sweat test (ST) is the current diagnostic gold standard for cystic fibrosis (CF). Many CF centres have switched from the Gibson-Cooke method to the Macroduct system-based method. We used these methods simultaneously to compare CF screening outcomes. STs using both methods were performed simultaneously between March and December 2022 at CF Centre in Florence. We included newborns who underwent newborn bloodspot screening (NBS), newborns undergoing transfusion immediately after birth, and children with CF screen-positive, inconclusive diagnosis (CFSPID). We assessed 72 subjects (median age 4.4 months; range 0-76.7): 30 (41.7%) NBS-positive, 18 (25.0%) newborns who underwent transfusion, and 24 (33.3%) children with CFSPID. No significant differences were found between valid sample numbers, by patient ages and groups (p = 0.10) and between chloride concentrations (p = 0.13), except for sweat chloride (SC) measured by the Gibson-Cooke and Macroduct methods in CFSPID group (29.0, IQR: 20.0-48.0 and 22.5, IQR: 15.5-30.8, respectively; p = 0.01). The Macroduct and Gibson-Cooke methods showed substantial agreement with the SC values, except for CFSPID, whose result may depend on the method of sweat collection. In case of invalid values with Macroduct, the test should be repeated with Gibson-Cooke method.

Lung clearance index in children with cystic fibrosis previously diagnosed with CRMS/CFSPID: A monocentric prospective experience

INTRODUCTION

No data are available on the values and role of lung clearance index (LCI) in cystic fibrosis (CF) Screen Positive Inconclusive Diagnosis (CFSPID) progressed to CF diagnosis (CFSPID > CF). This study aimed to assess the value of the LCI in correctly predicting the progression of CFSPID to CF.

METHODS

This is a prospective study carried out at the CF Regional Center of Florence, Italy from September 1, 2019. We compared LCI values in children with CF diagnosed for positive newborn screening (NBS), CFSPID or CFSPID > CF for pathological sweat chloride (SC). The Exhalyzer-D (EcoMedics AG, Duernten, Switzerland, software version 3.3.1) was used to conduct the LCI tests, every 6 months on stable children.

RESULTS

Forty-two cooperating children were enrolled (mean age at LCI tests: 5.4 years, range: 2.7-8.7): 26 (62%) had CF, 8 (19%) were CFSPID > CF for positive SC, while 8 (19%) kept the CFSPID label at last LCI test. The mean LCI value for patients with CF (7.39; 5.98-10.24) was statistically higher compared to both the mean LCI in the CFSPID > CF (6.62; 5.69-7.58) and in CFSPID (6.56; 5.64-7.21).

CONCLUSIONS

Most of asymptomatic CFSPID or progressed to CF have normal LCI. Further data on the longitudinal course of LCI during follow up of CFSPID and on larger cohorts is needed.

Clinical Consequences and Functional Impact of the Rare S737F CFTR Variant and Its Responsiveness to CFTR Modulators

S737F is a Cystic Fibrosis (CF) transmembrane conductance regulator (CFTR) missense variant. The aim of our study was to describe the clinical features of a cohort of individuals carrying this variant. In parallel, by exploiting ex vivo functional and molecular analyses on nasal epithelia derived from a subset of S737F carriers, we evaluated its functional impact on CFTR protein as well as its responsiveness to CFTR modulators. We retrospectively collected clinical data of all individuals bearing at least one S737F CFTR variant and followed at the CF Centre of Tuscany region (Italy). Nasal brushing was performed in cooperating individuals. At study end clinical data were available for 10 subjects (mean age: 14 years; range 1–44 years; 3 adult individuals). Five asymptomatic subjects had CF, 2 were CRMS/CFSPID and 3 had an inconclusive diagnosis. Ex vivo analysis on nasal epithelia demonstrated different levels of CF activity. In particular, epithelia derived from asymptomatic CF subjects and from one of the subjects with inconclusive diagnosis showed reduced CFTR activity that could be rescued by treatment with CFTR modulators. On the contrary, in the epithelia derived from the other two individuals with an inconclusive diagnosis, the CFTR-mediated current was similar to that observed in epithelia derived from healthy donors. In vitro functional and biochemical analysis on S737F-CFTR expressed in immortalized bronchial cells highlighted a modest impairment of the channel activity, that was improved by treatment with ivacaftor alone or in combination with tezacaftor/elexacaftor. Our study provide evidence towards the evaluation of CFTR function on ex vivo nasal epithelial cell models as a new assay to help clinicians to classify individuals, in presence of discordance between clinical picture, sweat test and genetic profile.

Management of pulmonary aspergillosis in children: a systematic review

Invasive pulmonary aspergillosis (IPA) is a severe condition in immunocompromised children, but the optimal management is still under debate. In order to better clarify this issue, a literature search was performed through MEDLINE/PubMed database to describe current risk factors and diagnostic, therapeutic and prophylactic tools for invasive pulmonary aspergillosis (IPA) in the paediatric age. Observational studies and clinical trials regarding diagnosis, treatment and prophylaxis were considered, and results were summarised. Five clinical trials and 25 observational studies (4453 patients) were included.Haematological malignancies, previous organ transplant and other primary or acquired immunodeficiency were identified as risk factors for IPA in children.Current diagnostic criteria distinguish between "proven", "probable" and "possible" disease. Consecutive galactomannan assays have good sensitivity and specificity, especially when performed on broncho-alveolar lavage. At the same time, β-D-glucan should not be used since cut-off in children is unclear. PCR assays cannot currently be recommended for routine use.Voriconazole is the recommended first-line agent for IPA in children older than 2 years of age. Liposomal amphotericin B is preferred in younger patients or cases of intolerance to voriconazole. Its plasma concentrations should be monitored throughout the treatment. The optimal duration of therapy has yet to be determined. Posaconazole is the preferred prophylactic agent in children older than 13 years old, whereas oral voriconazole or itraconazole are the drugs of choice for those between 2-12 years. Further good-quality studies are warranted to improve clinical practice.

Can percussive intrapulmonary ventilation improve the efficacy of physiotherapy in children with cystic fibrosis?

Lung disease in cystic fibrosis (CF) is characterized by reduced mucociliary clearance, airway plugging, recurrent infections, and chronic pulmonary inflammation. Patients who are affected undergo daily respiratory physiotherapy to improve airway clearance. Intrapulmonary percussive ventilation (IPV) is a technique used in clinical practice, but it is not commonly used in CF patients. Evidence for various respiratory pathologies, particularly in children, is still lacking. We present the case of an 11-year-old boy with cystic fibrosis who did not respond to traditional respiratory physiotherapy techniques. We proposed and tested the use of IPV during hospitalization. In this case, the use of IPV in physiotherapy treatment reduced the need for intravenous antibiotics, hospitalization, and improved radiologic features. IPV can be used successfully in CF patients who are resistant to traditional physiotherapy techniques.

A Multicentre Italian Study on the Psychological Impact of an Inconclusive Cystic Fibrosis Diagnosis after Positive Neonatal Screening

BACKGROUND

An inconclusive diagnosis of cystic fibrosis (CF) after positive newborn screening (NBS) may cause parental distress. We compared the psychological impact of CF transmembrane conductance regulator-related metabolic syndrome (CRMS)/CF screen-positive, inconclusive diagnosis (CFSPID), and clear CF diagnosis, on parents.

METHODS

The participants were administered the Generalized Anxiety Disorder Scale, Patient Health Questionnaire-9, and the Italian version of the Impact of Event Scale-Revised as quantitative tools and semi-structured interviews as qualitative tools. Parental experience, child representation, relationships, future information, and perception of health status were investigated. Interviews were recorded and transcribed verbatim maintaining anonymity.

RESULTS

Thirty-two families were enrolled: sixteen with CF and CRMS/CFSPID, respectively. Anxiety and depression values were high in both groups, as were the measurement of traumatic impact subscales: avoidance, intrusiveness, and hyperarousal. The children's health was evaluated by respective parents as being nearly healthy.

CONCLUSIONS

Our results highlight negative psychological impacts, including emotional and affective representations, on parents of children with inconclusive CF diagnosis compared with those with clear diagnosis.

Different management approaches and outcome for infants with an inconclusive diagnosis following newborn screening for cystic fibrosis (CRMS/CFSPID) and Pseudomonas aeruginosa isolation

INTRODUCTION

Evidence is currently lacking to guide the management of cystic fibrosis (CF) transmembrane conductance regulator-related metabolic syndrome CF screen-positive inconclusive diagnosis (CRMS/CFSPID) with Pseudomonas aeruginosa (Pa)-positive respiratory culture. This study assessed the clinical data, management, and outcomes of an Italian cohort of CRMS/CFSPID infants with Pa isolated from their airways.

METHODS

Data of Pa-positive CRMS/CFSPID infants born between January 2011 and August 2018 and followed at five CF Italian centres were retrospectively extracted. Further data were collected until June 2021 to assess outcomes, prevalence of subjects treated with antimicrobials, and treatment type and duration.

RESULTS

Forty-three asymptomatic CRMS/CFSPID patients (median age on 30 June 2021, 82 months; interquartile range [IQR], 63-98 months) with at least one positive airway culture for non-mucoid Pa (median age at first isolation, 18.7 months; IQR, 7-25 months) were enrolled. Of them, 24 (55.8%) underwent anti-Pa therapy. Pa clearance occurred in 22 (91.6%) of 24 patients versus spontaneous clearance in 16 of 19 (84.2%) untreated patients (chi-square, 0.5737; p = 0.44878). After a median follow-up of 6.2 years (IQR, 3.0-9.9), 7 (16.3%) were diagnosed with CF after a pathological sweat test (median age, 43 months; IQR, 28-77 months), 3 (7%) developed recurrent pancreatitis or isolated bronchiectasis consistent with CFTR-related disorder, and the CRMS/CFSPID classification remained in 33 (76.7%).

CONCLUSIONS

Pa detection frequently occurs in asymptomatic infants with CRMS/CFSPID but tends to clear spontaneously. More studies are needed to determine if Pa isolation can predict evolution.

Effect of Dornase Alfa on the Lung Clearance Index in Children with Cystic Fibrosis: A Lesson from a Case Series

BACKGROUND

Dornase alfa (DNase) is the only mucus-degrading agent that has proven efficacy in cystic fibrosis (CF). Few studies have evaluated the effects of DNase on the lung clearance index (LCI). We report the experience of two CF centers in which LCI monitoring was used to evaluate the efficacy of DNase therapy.

METHODS

This is a prospective and observational study, evaluating the effects of DNase therapy on LCI values in three CF children followed at CF centers in Florence and Catania, Italy. In both centers, LCI was performed routinely, every 3-6 months, based on the clinical picture and severity of the lung disease. In this study, we evaluated the LCI before and after long-term DNase therapy.

RESULTS

DNase improved LCI values in the absence of respiratory exacerbations: in case n. 1 LCI decreased by 39% in 16 months (from 11.1 to 6.8); in case n. 2 by 20% in 12 months (from 9.3 to 7.4); in case n. 3 by 24% in 16 months (from 9.3 to 7.0).

CONCLUSIONS

This case series confirms the efficacy of DNase therapy in CF children, as demonstrated by the LCI reduction in treated patients. Furthermore, our results suggest that LCI is a sensitive marker of disease and can be used for the evaluation of response to treatment.

Modulator Therapy in Cystic Fibrosis Patients with cis Variants in F508del Complex Allele: A Short-Term Observational Case Series

Previous studies reported the influence of cis variants in F508del cystic fibrosis (CF) patients in their responses to CFTR modulators. The current study is a prospective, observational study involving three patients with CF and pancreatic insufficiency, carrying a complex allele including F508del with A238V, I1027T, or L467F. We report clinical data before and after 4 weeks of treatment with tezacaftor (TEZ)/ivacaftor (IVA), elexacaftor (ELX)/TEZ/IVA, and lumacaftor (LUM)/IVA for patients with complex alleles A238V, I1027T, and L467F, respectively. The 50-year-old patient bearing F508del;A238V/D1152H showed a normal sweat test (13 mEq/L) and improvements in forced expiratory volume in the first second (FEV₁) (+7 points), body mass index (BMI) (+0.85), and respiratory CF Questionnaire-Revised (CFQ-R) domain (+22.2 points). The 12-year-old patient bearing F508del;I1027T/R709X showed an improvement in a sweat test (−40 mEq/l), FEV₁ (+9 points) and the respiratory CFQ-R domain (+16.7 points). No changes in outcomes were observed for the 6-year-old patient F508del;L467F/F508del. Our data highlight that the reported variants do not modify the phenotypic expression of F508del. Searching L467F is crucial in CF patients with F508del nonresponsive to ELX/TEZ/IVA. Further data are needed to evaluate the clinical effect of these variants after a longer follow up.

Dornase alfa in Cystic Fibrosis: indications, comparative studies and effects on lung clearance index

Cystic fibrosis (CF) is the most common inherited disease in Caucasian populations, affecting around 50,000 patients in Europe and 30,000 in United States. A mutation in CF trans-membrane conductance regulator (CFTR) gene changes a protein (a regulated chloride channel), which is expressed in many tissues. Defective CFTR results in reduced chloride secretion and an overage absorption of sodium across the epithelia, leading to thickened secretions in organs such as pancreas and lung. Gradually, there have been considerable improvements in the survival of people with CF, thanks to substantial changes in specialized CF care and the discovery of new CFTR modulators drugs. Nevertheless, lung disease remains the most common cause of death. For these reasons improvement of sputum clearance is a major therapeutic aim in CF. So far, symptomatic mucolytic therapy is mainly based on inhalation of dornase alfa, hypertonic saline or mannitol, in combination with physiotherapy. The major component of mucus in CF is pus including viscous material such as polymerized DNA derived from degraded neutrophils. Dornase alfa cleaves the DNA released from the neutrophils and reduces mucous viscosity, and further prevent airway infections and damage to the lung parenchyma. In this review we will summarize the current knowledge on dornase alfa in the treatment of CF lung disease, especially highlighting the positive effect on lung clearance index, a sensitive measure of ventilation inhomogeneity.

Clinical course and risk factors for severe COVID-19 among Italian patients with cystic fibrosis: a study within the Italian Cystic Fibrosis Society

PURPOSE

To describe the clinical course of COVID-19 in patients with cystic fibrosis (CF) and to identify risk factors for severe COVID-19.

METHODS

We conducted a prospective study within the Italian CF Society. CF centers collected baseline and follow-up data of patients with virologically confirmed SARS-CoV-2 infection between March 2020 and June 2021. Odds ratios (ORs) for severe SARS-CoV-2 (as defined by hospital admission) were estimated by logistic regression models.

RESULTS

The study included 236 patients with positive molecular test for SARS-CoV-2. Six patients died, 43 patients were admitted to hospital, 4 admitted to intensive care unit. Pancreatic insufficiency was associated with increased risk of severe COVID-19 (OR 4.04, 95% CI 1.52; 10.8). After adjusting for age and pancreatic insufficiency, forced expiratory volume in one second (FEVp) < 40% (OR 4.54, 95% CI 1.56; 13.2), oxygen therapy (OR 12.3, 95% CI 2.91-51.7), underweight (OR 2.92, 95% CI 1.12; 7.57), organ transplantation (OR 7.31, 95% CI 2.59; 20.7), diabetes (OR 2.67, 95% CI 1.23; 5.80) and liver disease (OR 3.67, 95% CI 1.77; 7.59) were associated with increased risk of severe COVID-19, while use of dornase alfa was associated with a reduced risk (OR 0.34, 95% CI 0.13-0.88). No significant changes were observed in FEVp from baseline to a median follow-up of 2 months (median difference: 0, interquartile range: - 4; 5, P = 0.62).

CONCLUSION

Clinical features indicative of severe form of CF are associated with increased risk of COVID-19 hospitalization. SARS-CoV-2 infected patients do not experience a deterioration of respiratory function.

Clinical outcomes of a large cohort of individuals with the F508del/5T;TG12 CFTR genotype

BACKGROUND

In recent years, patients with cystic fibrosis (CF) conductance regulator (CFTR) variant poly(T) sequences have been increasingly reported with a wide spectrum of clinical severity. We describe the long-term clinical outcomes and progression to a CF diagnosis over time in a large Italian cohort of patients carrying the CFTR F508del/5T;TG12 genotype.

METHODS

A retrospective analysis of subjects from 10 CF centres in Italy with the F508del/5T;TG12 genotype was performed. Demographic, clinical, microbiological, and biochemical data, as well as information about the follow-ups and complications of the enroled patients, were collected.

RESULTS

A total of 129 subjects (54 females; median age: 15.0 years, range: 0-58 years; 59 older than 18 years) were included. In terms of initial diagnoses, 30 were CF (23.3%), 41 were CFTR-related disorder (CFTR-RD) (31.7%), and 58 were CF transmembrane conductance regulator-related metabolic syndrome/cystic fibrosis screen positive, inconclusive diagnosis (CRMS/CFSPID) (45.0%). After a median follow-up of 6.7 years (range 0.2-25 years), 15 patients progressed to CF, bringing the total number of CF diagnoses to 45/129 (34.9%). Most of these patients had mild lung diseases with pancreatic sufficiency and a low prevalence of CF-related complications.

CONCLUSIONS

At the end of the study, 34.9% of subjects with the CFTR F508del/5T;TG12 genotype were diagnosed with CF. We suggest including patients with the F508del/5T;TG12 genotype in long-term follow-ups.

Six minute walk test in Italian children with cystic fibrosis aged 6 and 11

Six Minute Walk Test (6MWT) is a field exercise test widely used in clinical practice, both in adults and in pediatric patients. The primary aim of the study is to evaluate the physical performance of the subjects and compare them with the predicted Italian values. The secondary aim is to verify the possible relationship between the 6MWT distance (6MWD) and the clinical variables of the sample. Italian children between 6-11 years affected by CF were recruited from 9 regional centres for CF. Short questionnaire assessments about their health state and physical activity routine was administered. Anthropometric characteristics were measured before the test and, peripheral oxygen saturation (SpO2), heart and respiratory rate were measured before and after a 6-minute walk test. The tests were performed according to the American Thoracic Society (ATS) guidelines. 6MWD was compared with the predicted distance calculated by the reference equation for healthy subjects of the same age.A total of 132 children were recruited (70 male) and completed the assessment. The mean (±SD) for 6MWD was 557.4(±69.9), male = 551.4(±80.0), female = 560.4(±63.3), however the predicted distance mean was 605m. A total of 101(76.5%) subjects practice regular physical activity. A total of 31(23%) had a FEV1 lower than their Lower Limits of Normal (LLN). Functional performance on the 6MWT was poorer among the CF patients than among the predicted distance estimated with Italian values. The correlation with the amount of physical activity and 6MWD has been verified.

Effectiveness and safety of elexacaftor/tezacaftor/ivacaftor in patients with cystic fibrosis and advanced lung disease with the Phe508del/minimal function genotype

BACKGROUND

Elexacaftor/tezacaftor/ivacaftor (E/T/I) is a cystic fibrosis transmembrane conductance regulator (CFTR) triple combination therapy used for the treatment of cystic fibrosis (CF) in patients aged ≥12 years who have at least one copy of the Phe508del mutation (F) in the CFTR gene or another mutation that is responsive to treatment with E/T/I. This study determined the effectiveness and safety of E/T/I treatment in a cohort of CF patients.

METHODS

This retrospective cohort study collected data from the first 6 months of treatment of patients with CF, compound heterozygotes for the F and a minimal function (MF) mutations, enrolled in an E/T/I compassionate use program only available to patients having ppFEV₁<40 or who are considered for lung transplantation. Forty-seven patients were included. Follow-up was performed after 1, 3, and 6 months from the beginning of therapy, assessing lung function, body mass index (BMI), sweat chloride concentration (SCC), quality of life (QoL), and safety.

RESULTS

After 6 months of treatment, the mean (standard deviation (SD)) SCC decreased from 91.1 (19.3) mmol/L to 46.2 (24.2) mmol/L. The decrease of SCC was accompanied by improvement of lung function (mean (95% Confidence Interval (CI) absolute increase in ppFEV₁ was 10.69 (8.05,13.33) after 1 month and 14.16 (11.43, 16.89) after 6 months of treatment), nutrition (mean (SD) BMI increased from 20.7 (3.0) kg/m² at baseline to 22.6 (3.1) after 6 months), and QoL. No safety concerns were observed.

CONCLUSIONS

E/T/I was clinically effective and safe in patients with advanced CF lung disease with an F/MF genotype.

Hypertonic saline in people with cystic fibrosis: review of comparative studies and clinical practice

Cystic fibrosis (CF) is a multisystem disorder, caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. These cause a reduced secretion of chloride, a marked absorption of sodium and, therefore, of water, through the epithelium, resulting in the formation of thickened secretions in organs such as lung or pancreas. These viscous secretions lead to airway obstruction, chronic infection and inflammation resulting in progressive lung damage, bronchiectasis and eventual respiratory failure. Although the average life expectancy has increased over the last 30 years, lung disease is the most common cause of death in people with CF. For these reasons, the improvement of sputum clearance is a major therapeutic aim in CF and early initiation of airway clearance is widely recommended and implemented. Symptomatic mucolytic therapy today is mainly based on inhalation of DNase, hypertonic saline or mannitol, in combination with physiotherapy. Mucolytic agents break down the gel structure of mucus and therefore decrease its elasticity and viscosity, reducing the pulmonary exacerbation frequency and to improve and stabilize lung function. Nevertheless, high quality studies comparing these mucolytic drugs are still few, and the individual experiences of patients and caregivers explain the high variability of their use globally. This review will summarize the current knowledge on hypertonic saline in the treatment of CF lung disease. Furthermore, we report the real-world prescription of inhaled mucolytic agents in CF.

Effectiveness of Elexacaftor/Tezacaftor/Ivacaftor Therapy in Three Subjects with the Cystic Fibrosis Genotype Phe508del/Unknown and Advanced Lung Disease

We evaluated the effectiveness and safety of elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) in three subjects carrying the Phe508del/unknown CFTR genotype. An ex vivo analysis on nasal epithelial cells (NEC) indicated a significant improvement of CFTR gating activity after the treatment. Three patients were enrolled in an ELX/TEZ/IVA managed-access program, including subjects with the highest percent predicted Forced Expiratory Volume in the 1st second (ppFEV₁) < 40 in the preceding 3 months. Data were collected at baseline and after 8, 12 and 24 weeks of follow-up during treatment. All patients showed a considerable decrease of sweat chloride (i.e., meanly about 60 mmol/L as compared to baseline), relevant improvement of ppFEV₁ (i.e., >8) and six-minute walk test, and an increase in body mass index after the first 8 weeks of treatment. No pulmonary exacerbations occurred during the 24 weeks of treatment and all domains of the CF Questionnaire-Revised improved. No safety concerns related to the treatment occurred. This study demonstrates the benefit from the ELX/TEZ/IVA treatment in patients with CF with the Phe508del and one unidentified CFTR variant. The preliminary ex vivo analysis of the drug response on NEC helps to predict the in vivo therapeutic endpoints.

Elexacaftor-Tezacaftor-Ivacaftor Therapy for Cystic Fibrosis Patients with The F508del/Unknown Genotype

The new CFTR modulator combination, elexacaftor/tezacaftor/ivacaftor (Trikafta) was approved by the FDA in October 2019 for treatment of Cystic Fibrosis in patients 6 years of age or older who have at least one F508del mutation in one allele and a minimal-function or another F508del mutation in the other allele. However, there is a group of patients, in addition to those with rare mutations, in which despite the presence of a F508del in one allele, it was not possible to identify any mutation in the other allele. To date, these patients are excluded from treatment with Trikafta in Italy, where the CF patients carrying F508del/unknown represent about 1.3% (71 patients) of the overall Italian CF patients. In this paper we show that the Trikafta treatment of nasal epithelial cells, derived from F508del/Unknown patients, results in a significant rescue of CFTR activity. Based on our findings, we think that the F508del/Unknown patients considered in this study could obtain clinical benefits from Trikafta treatment, and we strongly suggest their eligibility for this type of treatment. This study, adding further evidence in the literature, once again confirms the validity of functional studies on nasal cells in the cystic fibrosis theratyping and personalized medicine.

A survey of the prevalence, management and outcome of infants with an inconclusive diagnosis following newborn bloodspot screening for cystic fibrosis (CRMS/CFSPID) in six Italian centres

OBJECTIVE

We evaluated the prevalence, Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene profile, clinical data, management and outcome for infants with a CFTR-related metabolic syndrome/CF Screen Positive, Inconclusive Diagnosis (CRMS/CFSPID) designation from six Italian centres.

METHODS

All newborn bloodspot screening (NBS) positive infants born from January 2011 to August 2018 with a CF diagnosis or a CRMS/CFSPID designation were enrolled. Data on sweat testing, genetics, clinical course and management were collected.

RESULTS

We enrolled 257 CF patientsand 336 infants with a CRMS/CFSPID designation (CF: CRMS/CFSPID ratio of 1:1.30).Blood immuno-reactive trypsinogen (IRT) was significantly lower in CRMS/CFSPID infants and the F508del variant accounted for only 20% of alleles. Children with CRMS/CFSPID showed a milder clinical course, pancreatic sufficiency compared to CF infants. Varied practice across centres was identified regarding sweat testing, chest radiograph (8-100%) and salt supplementation (11-90%). Eighteen (5.3%) CRMS/CFSPID infants converted or were reclassified to diagnosis of CF. Four infants (1.3%) developed a clinical feature consistent with a CFTR-related disorder (1.2%). Twenty-seven were re-classified as healthy carriers (8.0%) and 16 as healthy infants (4.8%).

CONCLUSIONS

We have identified considerable variability in the evaluation and management of infants with an inconclusive diagnosis following NBS across six Italian centres. CRMS/CFSPID is more regularly seen in this population compared to countries with higher prevalence of F508del.Conversion to a CF diagnosis was recorded in 18 (5.3%) of CRMS/CFSPID infants and in 16 was as a result of increasing sweat chloride concentration.

Ex vivo model predicted in vivo efficacy of CFTR modulator therapy in a child with rare genotype

BACKGROUND

New drugs that target the basic defect in cystic fibrosis (CF) patients may now be used in a large number of patients carrying responsive mutations. Nevertheless, further research is needed to extend the benefit of these treatments to patients with rare mutations that are still uncharacterized in vitro and that are not included in clinical trials. For this purpose, ex vivo models are necessary to preliminary assessing the effect of CFTR modulators in these cases.

METHOD

We report the clinical effectiveness of lumacaftor/ivacaftor therapy prescribed to a CF child with a rare genetic profile (p.Phe508del/p.Gly970Asp) after testing the drug on nasal epithelial cells. We observed a significant drop of the sweat chloride value, as of the lung clearance index. A longer follow-up period is needed to define the effects of therapy on pancreatic status, although an increase of the fecal elastase values was found.

CONCLUSION

Drug response obtained on nasal epithelial cells correlates with changes in vivo therapeutic endpoints and can be a predictor of clinical efficacy of novel drugs especially in pediatric patients.

The Risks of Complications During Endoscopic Sinus Surgery in Cystic Fibrosis Patients: An Anatomical and Endoscopic Study

OBJECTIVE/HYPOTHESIS

An increasing proportion of adult cystic fibrosis (CF) patients is being referred to endoscopic sinus surgery (ESS) in order to relieve the symptoms of chronic rhinosinusitis (CRS). Given that CFTR mutations profoundly alter sinonasal development, we want to explore the relationship between their peculiar surgical anatomy and the risk of postoperative complications.

STUDY DESIGN

Retrospective case-control study.

METHODS

Paranasal sinuses CT scans of 103 CF adult patients with CRS were compared to those belonging to a cohort of 100 non-CF adult patients to explore their anatomical differences. Secondly, CF and non-CF patients who received primary/revision ESS were analyzed in order to assess their preoperative CT scan in terms of surgically relevant variants, and according to the CLOSE checklist. Surgical outcomes were statistically compared in order to explore the differences between groups.

RESULTS

CF group presented more frequently with smaller and less pneumatized paranasal sinuses and a higher Lund-Mckay score compared with controls. No anatomical differences emerged in terms of genotype stratification. Non-CF CRS patients undergoing ESS showed a significantly deeper olfactory fossa and a more frequent supraorbital pneumatization compared to CF patients (P < .001 and P = .031, respectively). Whereas this latter group underwent more often aggressive surgical procedures (P = .001), no difference in terms of postoperative adverse events was found (P = .620).

CONCLUSIONS

Despite receiving more often aggressive ESS procedures, adult CF patients do not show an increased risk of postoperative complication and this may be linked to a different proportion of anatomical and surgically-relevant variants.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E2481-E2489, 2021.

Cystic fibrosis in Tuscany: evolution of newborn screening strategies over time to the present

BACKGROUND

Cystic fibrosis (CF) is a life-threatening disease affecting about 1:3000 newborns in Caucasian populations. The introduction of newborn screening for cystic fibrosis (CF NBS) has improved the clinical outcomes of individuals with CF through early diagnosis and early treatment. NBS strategies have been implemented over time. CF NBS was introduced extensively in 1984 in Tuscany, a region with 3.7 million people, characterized by a high allelic heterogeneity of CFTR gene.

AIM AND METHODS

The aim of the study is to present the results from 34 years (1984-2018) of CF NBS, retrospectively evaluating the sensitivity, specificity and predictive values of the tests. In particular, we studied the impact of the introduction of DNA molecular analysis in NBS in a region with high allelic heterogeneity, such as Tuscany.

RESULTS

Over these 34 years, 919,520 neonates were screened, using four different NBS strategies. From 1984 to 1991, CF NBS was performed by the determination of albumin on dried meconium (sensitivity 68.75%; specificity 99.82%). Subsequently, the analysis of immunoreactive trypsinogen on a blood spot was adopted as CF NBS protocol (sensitivity 83.33%; specificity 99.77%). From 1992 to 2010, this strategy was associated with lactase meconium dosage: IRT1/IRT2 + LACT protocol (sensitivity 87.50%; specificity 99.82%). From 2011, when the existing algorithm was integrated by analysis of CF causing variants of the CFTR gene (IRT1/IRT2 + LACT + IRT1/DNA protocol), a substantial improvement in sensitivity was seen (senisitivity 96.15%; specificity 99.75%). Other improved parameters with DNA analysis in the NBS programme, compared with the previous method, were the diagnosis time (52 days vs. 38 days) and the recall rate (0.58 to 0.38%).

CONCLUSION

The inclusion of DNA analysis in the NBS was a fundamental step in improving sensitivity, even in a region with high allelic variability.

Antimicrobial resistance in cystic fibrosis: A Delphi approach to defining best practices

BACKGROUND

Antimicrobial susceptibility testing (AST) is a cornerstone of infection management in cystic fibrosis. However, there is little evidence that AST predicts the clinical outcome of CF antimicrobial treatment. It has been suggested there is a need for careful consideration of current AST use by the CF community.

METHODS

We engaged a group of experts consisting of pulmonary (adult and pediatric) and infectious disease clinicians, microbiologists, and pharmacists representing a broad international experience. We conducted an iterative systematic survey (Delphi) to determine and quantify consensus regarding key questions facing CF clinicians in the use of respiratory culture results including what tests to order, when to obtain them, and how to act upon the results of the testing.

RESULTS

Consensus was reached for many questions but there was not universal agreement to the questions that were addressed. There were some differences with respect to cultures obtained for surveillance compared to when there is clinical worsening. Areas of general consensus include when and how respiratory cultures should be performed, what information should be reported, and when AST should be performed. A key finding is that clinical response to treatment is used to guide treatment decisions rather than AST results.

CONCLUSIONS

Recommendations are presented regarding questions related to microbiology testing for patients with CF. We have also offered recommendations for priority research questions.

Methicillin-resistant Staphylococcus aureus eradication in cystic fibrosis patients: A randomized multicenter study

BACKGROUND

Few studies, based on a limited number of patients using non-uniform therapeutic protocols, have analyzed Methicillin-resistant Staphylococcus aureus (MRSA) eradication.

METHODS

In a randomized multicenter trial conducted on patients with new-onset MRSA infection we evaluated the efficacy of an early eradication treatment (arm A) compared with an observational group (B). Arm A received oral rifampicin and trimethoprim/sulfamethoxazole (21 days). Patients' microbiological status, FEV1, BMI, pulmonary exacerbations and use of antibiotics were assessed.

RESULTS

Sixty-one patients were randomized. Twenty-nine (47.5%) patients were assigned to active arm A and 32 (52.5%) patients to observational arm B. Twenty-nine (47.5%) patients, 10 patients in arm A and 19 in arm B, dropped out of the study. At 6 months MRSA was eradicated in 12 (63.2%) out of 19 patients in arm A while spontaneous clearance was observed in 5 (38.5%) out of 13 patients in arm B. A per-protocol analysis showed a 24.7% difference in the proportion of MRSA clearance between the two groups (z = 1.37, P(Z>z) = 0.08). Twenty-seven patients, 15 (78.9%) out of 19 in arm A and 12 (92.3%) out of 13 in arm B, were able to perform spirometry. The mean (±SD) FEV1 change from baseline was 7.13% (±14.92) in arm A and -1.16% (±5.25) in arm B (p = 0.08). In the same period the BMI change (mean ±SD) from baseline was 0.54 (±1.33) kg/m2 in arm A and -0.38 (±1.56) kg/m2 in arm B (p = 0.08). At 6 months no statistically significant differences regarding the number of pulmonary exacerbations, days spent in hospital and use of antibiotics were observed between the two arms.

CONCLUSIONS

Although the statistical power of the study is limited, we found a 24.7% higher clearance of MRSA in the active arm than in the observational arm at 6 months. Patients in the active arm A also had favorable FEV1 and BMI tendencies.