Screening For Cystic Fibrosis Research Articles

International Perspectives of Extended Genetic Sequencing When Used as Part of Newborn Screening to Identify Cystic Fibrosis.

There is increasing interest in using extended genetic sequencing (EGS) in newborn screening (NBS) for cystic fibrosis (CF). How this is implemented will change the number of children being given an uncertain outcome of CRMS/CFSPID (cystic fibrosis transmembrane conductance regulator (CFTR)-related metabolic syndrome/CF Screen Positive Inconclusive Diagnosis), probable carrier results, and the number of missed CF diagnoses. An international survey of CF health professionals was used to gather views on two approaches to EGS-specific (may reduce detection of CRMS/CFSID but miss some CF cases) versus sensitive (may increase detection of CRMS/CFSPID but avoid missing more CF cases). Health professionals acknowledged the anxiety caused to parents (and health professionals) from the uncertainty surrounding the prognosis and management of CRMS/CFSPID. However, most preferred the sensitive approach, as overall, identifying more cases of CRMS/CFSPID was viewed as less physically and psychologically damaging than a missed case of CF. The importance of early diagnosis and treatment for CF to ensure better health outcomes and reducing diagnostic odysseys for parents were highlighted. A potential benefit to identifying more children with CRMS/CFSPID included increasing knowledge to obtain a better understanding of how these children should best be managed in the future.

Cystic fibrosis newborn screening in Switzerland – evaluation and scenarios for improvement after 11 years of follow-up

BackgroundNewborn bloodspot screening (NBS) for cystic fibrosis (CF) is important for early diagnosis and treatment. However, screening can lead to false-positive results leading to unnecessary follow-up tests and distress. This study evaluated the 11-year performance of the Swiss CF-NBS programme, estimated optimal cut-offs for immunoreactive trypsinogen (IRT), and examined how simulated algorithms would change performance. MethodsThe Swiss CF-NBS is based on an IRT–DNA algorithm with a second IRT (IRT-2) as safety net. We analysed data from 2011 to 2021, covering 959,006 IRT-1 analyses and 282 children with CF. We studied performance based on European Cystic Fibrosis Society (ECFS) standards including sensitivity, specificity, positive predictive value (PPV), false negative rate, and second heel-prick tests; identified optimal IRT cut-offs using receiver operating characteristics (ROC) curves; and calculated performance for simulated algorithms with different cut-offs for IRT-1, IRT-2, and safety net. ResultsThe Swiss CF-NBS showed excellent sensitivity (96 %, 10 false negative cases) but moderate PPV (25 %). Optimal IRT-1 and IRT-2 cut-offs were identified at 2.7 (>99th percentile) and 5.9 (>99.8th percentile) z-scores, respectively. Analysis of simulated algorithms showed that removing the safety net from the current algorithm could increase PPV to 30 % and eliminate >200 second heel-prick tests per year, while keeping sensitivity at 95 %. ConclusionThe Swiss CF-NBS program performed well over 11 years but did not achieve the ECFS standards for PPV (≥30 %). Modifying or removing the safety net could improve PPV and reduce unnecessary follow-up tests while maintaining the ECFS standards for sensitivity.

Family case of cystic fibrosis

Cystic fibrosis is an autosomal recessively inherited monogenic disease caused by a mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, located on the long arm of chromosome 7 (7q31.2). This mutation results in a disruption in the transport of sodium and chloride ions between intercellular fluid and the epithelial cells of the excretory ducts of the exocrine glands. This paper presents the description of a family case of cystic fibrosis involving two patients who have been under observation since birth and are sisters (patient A – 4 years 10 months, patient B – 1 year 11 months). In both patients, neonatal screening and sequential diagnosis of cystic fibrosis identified the DF508/CFTRdele2.3(21kb) mutation, the most prevalent among the Caucasian population in the Russian Federation. The primary concern in managing both patients is the correction of nutritional status and minimization of exacerbations of chronic bronchopulmonary inflammation. To determine the management strategy for these patients, a consultation was held with Dr. E.I. Kondratyeva, a leading cystic fibrosis expert and professor at the MGSC Institute, who serves as the head of the Scientific and Clinical Department of Cystic Fibrosis and the Department of Genetics of Respiratory System Diseases, an expert of the European Society for Cystic Fibrosis Committee on Diagnostics and Registry, and Deputy Chief for Scientific Work of Research Clinical Institute of Childhood of the Ministry of Health of the Moscow Region. The peculiarity of the presented clinical cases lies in the fact that within one family, with an interval of 3 years, two girls with severe disease were born. Early diagnosis was performed for both, which has allowed for the slowing down of the pathology's progression.

Stakeholder Views of the Proposed Introduction of Next Generation Sequencing into the Cystic Fibrosis Screening Protocol in England.

The project aimed to gather, analyse, and compare the views of stakeholders about the proposed UK cystic fibrosis (CF) screening protocol incorporating next generation sequencing (NGS). The study design was based on principles of Q-methodology with a willingness-to-pay exercise. Participants were recruited from 12 CF centres in the UK. The study contained twenty-eight adults who have experience with CF (parents of children with CF (n = 21), including parents of children with CF transmembrane conductance regulator (CFTR)-related metabolic syndrome (CRMS)/CF screen positive-inconclusive diagnosis (CFSPID), an uncertain outcome (n = 3), and adults with CF (n = 4)), and nine health professionals involved in caring for children with CF. Parents and health professionals expressed a preference for a sensitive approach to NGS. This was influenced by the importance participants placed on not missing any children with CF via screening and the balance of harm between missing a case of CF compared to picking up more children with an uncertain outcome (CRMS/CFSPID). Given the preference for a sensitive approach, the need for adequate explanations about potential outcomes including uncertainty (CFSPID) at the time of screening was emphasized. More research is needed to inform definitive guidelines for managing children with an uncertain outcome following CF screening.

Rate and predictors of insufficient sweat volume in very young infants after pilocarpine gel iontophoresis: prospective, population-based study

ObjectiveTo verify the rate and predictors of ‘quantity not sufficient’ (QNS) among Brazilian infants younger than 3 months with positive newborn screening (NBS) for cystic fibrosis (CF).DesignProspective, population-based study.SettingPublic Statewide...

Influence of Season, Storage Temperature and Time of Sample Collection in Pancreatitis-Associated Protein-Based Algorithms for Newborn Screening for Cystic Fibrosis.

Newborn screening (NBS) for cystic fibrosis (CF) based on pancreatitis-associated protein (PAP) has been performed for several years. While some influencing factors are known, there is currently a lack of information on the influence of seasonal temperature on PAP determination or on the course of PAP blood concentration in infants during the first year of life. Using data from two PAP studies at the Heidelberg NBS centre and storage experiments, we compared PAP determinations in summer and winter and determined the direct influence of temperature. In addition, PAP concentrations measured in CF-NBS, between days 21-35 and 36-365, were compared. Over a 7-year period, we found no significant differences between PAP concentrations determined in summer or winter. We also found no differences in PAP determination after 8 days of storage at 4 °C, room temperature or 37 °C. When stored for up to 3 months, PAP samples remained stable at 4 °C, but not at room temperature (p = 0.007). After birth, PAP in neonatal blood showed a significant increasing trend up to the 96th hour of life (p < 0.0001). During the first year of life, blood PAP concentrations continued to increase in both CF- (36-72 h vs. 36-365 d p < 0.0001) and non-CF infants (36-72 h vs. 36-365 d p < 0.0001). Seasonal effects in central Europe appear to have a limited impact on PAP determination. The impact of the increase in blood PAP during the critical period for CF-NBS and beyond on the applicability and performance of PAP-based CF-NBS algorithms needs to be re-discussed.

The Psychological Impact on Parents of Children who Receive an Inconclusive Diagnosis for Cystic Fibrosis following Newborn Screening: A Systematic Mini-Review.

Newborn screening (NBS) has been available for the diagnosis of cystic fibrosis (CF) over the last decades. Through the implementation of NBS, a new designation emerged, that of CF related metabolic syndrome (CRMS) or cystic fibrosis screen positive inconclusive diagnosis (CFSPID). As there is uncertainty regarding the clinical progression of these infants to CF, some studies have investigated the psychological impact of CRMS/CFSPID on their parents. This systematic narrative review aimed to describe the findings of the relevant studies. The number of studies is limited and the study samples are relatively small. It seems that there is a negative impact of CRMS/CFSPID on parental mental health. While some studies indicated similar levels of parental anxiety among those with infants diagnosed with CF and those with CRMS/CFSPID, not all studies reached the same conclusion. Parental uncertainty represents another mental dimension of the impact associated with the designation of CRMS/CFSPID. These observations suggest that parents of infants with CRMS/CFSPID should be provided with effective communication, and it may also be beneficial to consider parental mental screening. More robust and long-term studies are required to detect differences in parental emotional status between those with infants diagnosed with CF and those with CRMS/CFSPID.

Multisite Verification of a Targeted CFTR Polymerase Chain Reaction/Capillary Electrophoresis Assay That Evaluates Pathogenic Variants Across Diverse Ethnic and Ancestral Groups.

Existing targeted cystic fibrosis screening assays miss important pathogenic CFTR variants in the ethnically diverse US population. To evaluate the analytic performance of a multiplex polymerase chain reaction (PCR)/capillary electrophoresis (CE) CFTR assay panel that simultaneously interrogates primary pathogenic variants of different ethnic/ancestral groups. Performance characteristic assessment and variant coverage comparison of the panel with a focus on ethnicity-specific CFTR variants were performed. Sample DNA was primarily from whole blood or cell lines. Detection of CFTR carriers was compared across several commercially available CFTR kits and recommended variant sets based on panel content. The panel interrogated 65 pathogenic CFTR variants representing 92% coverage from a recent genomic sequencing survey of the US population, including 4 variants with top 5 frequency in African or Asian populations not reflected in other targeted panels. In simulation studies, the panel represented 95% of carriers across the global population, resulting in 6.9% to 19.0% higher carrier detection rate compared with 10 targeted panels or variant sets. Precision and sensitivity/specificity were 100% concordant. Multisite sample-level genotyping accuracy was 99.2%. Across PCR and CE instruments, sample-level genotyping accuracy was 97.1%, with greater than 99% agreement for all variant-level metrics. The CFTR assay achieves 92% or higher coverage of CFTR variants in diverse populations and provides improved pan-ethnic coverage of minority subgroups of the US populace. The assay can be completed within 5 hours from DNA sample to genotype, and performance data exceed acceptance criteria for analytic metrics. This assay panel content may help address gaps in ancestry-specific CFTR genotypes while providing a streamlined procedure with rapidly generated results.

Outcome data from 15 years of cystic fibrosis newborn screening in a large UK region

BackgroundThe West Midlands Newborn Bloodspot Screening Laboratory is one of 16 in the UK and serves two tertiary paediatric cystic fibrosis (CF) centres (Staffordshire Children’s Hospital at Royal Stoke and...

The new face of cystic fibrosis in the era of population genetic carrier screening.

Population genetic carrier screening (PGCS) for cystic fibrosis (CF) has been offered to couples in Israel since 1999 and was included in a fully subsidized national program in 2008. We evaluated the impact of PGCS on CF incidence, genetic and clinical features. This was a retrospective national study. Demographic and clinical characteristics of children with CF born in Israel between 2008 and 2018 were obtained from the national CF registry and from patients' medical records. Data on CF births, preimplantation genetic testing (PGT), pregnancy termination and de-identified data from the PGCS program were collected. CF births per 100,000 live births decreased from 8.29 in 2008 to 0.54 in 2018 (IRR=0.84, p<0.001). The CF pregnancy termination rate did not change (IRR=1, p=0.9) while the CF-related PGT rate increased markedly (IRR=1.33, p<0.001). One hundred and two children were born with CF between 2008 and 2018 with a median age at diagnosis of 4.8 months, range 0-111 months. Unlike the generally high uptake nationally, 65/102 had not performed PGCS. Even if all had utilized PGCS, only 51 would have been detected by the existing genetic screening panel. Clinically, 34% of children were pancreatic sufficient compared to 23% before 2008 (p=0.04). Since institution of a nationwide PGCS program, the birth of children with CF decreased markedly. Residual function variants and pancreatic sufficiency were more common. A broader genetic screening panel and increased PGCS utilization may further decrease the birth of children with CF.

Vergleich von Diagnosedaten nach der Einführung des Mukoviszidosescreenings bei Neugeborenen in Deutschland

ZusammenfassungHintergrundZum 01.09.2016 wurde das Neugeborenenscreening (NGS) auf Mukoviszidose (Cystic Fibrosis – CF) in Deutschland eingeführt. Bisher gibt es keinen epidemiologischen Goldstandard für die Erfassung der Diagnosezahlen. Daher werden Daten der in der Konfirmationsdiagnostik bestätigten Fälle der Deutschen Gesellschaft für Neugeborenenscreening (DGNS) und die Diagnosehäufigkeiten des Deutschen Mukoviszidoseregisters (DMR) gegenübergestellt. Dies kann auch die Evaluation des CF-Screenings unterstützen. Ziel der Arbeit ist es, die Daten der DGNS und des DMR zu vergleichen und Limitationen sowie Stärken dieser Datenquellen darzustellen.MethodenAnalysiert werden die Mukoviszidose-Diagnosedaten der DGNS (Datenstand 14.04.2023) und des DMR (Datenstand 12.04.2023) für 2017–2021 geborene Kinder im Hinblick auf Häufigkeiten, Anzahl falsch-negativ Gescreenter und Verhältnis CF zu „Fällen mit positivem Mukoviszidosescreening und unklarer Konfirmationsdiagnostik“ (CFSPID).ErgebnisseDer DGNS liegen 767 Datensätze von Neugeborenen mit CF/CFSPID vor, dem DMR 910 bestätigte Diagnosefälle CF/CFSPID. Ein falsch-negatives Screening wird von der DGNS für 37/767 (4,8 %) und vom DMR für 49/910 (5,4 %) berichtet. Das Verhältnis von CF zu CFSPID beträgt 17,4:1 (DGNS, 2017–2020) bzw. 28,1:1 (DMR).DiskussionDie DGNS und das DMR liefern bei unterschiedlichen Stärken in der Dokumentation der Screening-(DGNS) und Diagnosedaten (DMR) wichtige Anhaltspunkte für die Anzahl neu diagnostizierter Mukoviszidosepatienten nach Einführung des NGS. Gesetzliche Vorgaben zur Nachverfolgung der Gescreenten und Erfassung aller Kinder mit Mukoviszidose sowie der Datenaustausch zwischen DGNS und DMR könnten zukünftig die Evaluation verbessern.

A clinical case of primary ciliary dyskinesia in a child under one year old with a pathogenic genetic variant of the DNAH5 gene described for the first time

Relevance: primary ciliary dyskinesia (PCD) is a rare hereditary autosomal recessive disease from the group of ciliopathies, which is based on a defect in the ultrastructure of the cilia of the epithelium of the respiratory tract and similar structures, leading to a violation of their motor function. It is characterized by the defeat of all parts of the respiratory tract with the formation of a chronic inflammatory process and bronchiectasis. About half of patients with PCD have a complete or incomplete reverse arrangement of internal organs with various variants of heterotaxy (situs inversus). Primary ciliary dyskinesia should be differentiated from cystic fibrosis, primary immunodeficiency conditions, congenital anomalies of the structure of the bronchial tree, bronchiectasis of other origin, bronchial asthma, congenital anomalies of the cardiovascular system. Objective: describe the clinical case of a PCD patient with the first-described pathogenic variant of the nucleotide sequence (chr5:13700862CCATAGA&gt;C) of the DNAH5 gene to familiarize doctors with the clinical features of the disease and modern diagnostic capabilities. Materials and methods: the data from the patient’s medical history, transmission electron microscopy to detect anomalies in the structure of cilia in the biopsy of the nasal mucosa and the results of molecular genetic diagnostics were used. Results. The patient was admitted for 8 months for examination and treatment in June 2022. A child from the 1st pregnancy, the first birth at 43 weeks. From anamnesis: suffered intrauterine pneumonia, otitis media without hearing loss, obstructive bronchitis, episodes of apnea. Neonatal screening for cystic fibrosis is negative. According to the PICADOR scale, 12 points were obtained. On high-speed video microscopy of cilia, there is a violation of the movements of the cilia. On computed tomography of the chest organs, the reverse location of the internal organs was noted, there were no pathological changes in the lungs. The total absence of external and internal dynein handles on transmission electron microscopy was revealed. Exome sequencing revealed the previously described variant of the nucleotide sequence in exon 68 of the DNAH5 gene (chr5:13735348G&gt; A) in a heterozygous state. Also, a previously undescribed variant of the nucleotide sequence (chr5:13700862CCATAGA&gt; C) in a heterozygous state was detected in exon 78 of the DNAH5 gene. Conclusion: modern possibilities of PCD diagnostics are demonstrated by the example of clinical observation. It is noted that patients with suspected PCD need a comprehensive examination. A pathogenic variant of the nucleotide sequence (chr5:13700862CCATAGA&gt;C) of the DNAH5 gene in a heterozygous state has been described for the first time, leading to the deletion of two amino acids without shifting the reading frame (c.13604_13609del p. (Val4535_Tyr4536del); NM_001369.3), which will help for the diagnosis of PCD in the future.

Assessment of the effectiveness of a new neonatal screening algorithm for cystic fibrosis

Relevance All over the world, neonatal screening protocols are being improved in order to reduce the time of diagnosis, simplify the examination procedure, and reduce the number of false positive and false negative results of neonatal screening. In most European countries, the best neonatal screening algorithm is molecular genetic testing. Objective: Evaluate the effectiveness of the new cystic fibrosis screening protocol algorithm, which, in the first step, determines the immunoreactive trypsin (IRT) level from one dry spot and performs DNA diagnostics (36 most frequent mutations) in patients with increased IRT. Compare the economic costs of screening by two algorithms (existing and alternative). Materials and methods: two parallel algorithms were used for neonatal screening. Which was performed on 56,534 infants in the Moscow Region from March to November 2022. The current three-stage algorithm was used, which involves re-blood sampling from newborns at risk 3-4 weeks after the first blood sampling and a sweat test. In the new algorithm, newborns with an elevated IRT 1 level at the 1st week of life underwent a molecular genetic study (search for frequent mutations in the CFTR-36 variants gene, sequencing of individual locus of the CFTR gene for control purposes) in the same dry blood spot used for screening. Results: out of 56,534 test forms received, 607 (1.07%) newborns with a positive test for IRT were identified for neonatal screening in a laboratory from the Moscow region, of which 501 (82.5%) samples were selected, where the level of RTI1 exceeded the cut-off level (65 ng / ml), which were sent for molecular genetic research in order to search for pathogenic variants in the CFTR gene. 106 (17.5%) newborns did not complete the examination. Positive results of confirmatory diagnosis were obtained in 6 infants, which accounted for 0.01% of the number of children who underwent screening and 1.2% of the number of children with neonatal hypertrypsinogenemia. Conclusion: the positive effects of the new algorithm are to reduce psychological tension in families during examination by reducing the time of diagnosis, no need for repeated blood sampling on the 21st-28th day of life, reduction of the time of diagnosis, prevention of nutritional deficiencies in children during the first months of life and life-threatening complications. Reducing the number of children with incomplete testing for cystic fibrosis, economic benefit. The negative effects of the new algorithm are that it is possible to miss a patient with cystic fibrosis who does not have any of the common pathogenic variants in the CFTR gene.

684 A quality improvement initiative to improve timeliness of sweat test referral after out-of-range newborn screen for cystic fibrosis

684 A quality improvement initiative to improve timeliness of sweat test referral after out-of-range newborn screen for cystic fibrosis

611 Quantity-not-sufficient sweat test in children undergoing newborn screening for cystic fibrosis

611 Quantity-not-sufficient sweat test in children undergoing newborn screening for cystic fibrosis

593 Validation of palmar aquagenic wrinkling as an adjuvant for cystic fibrosis screening in the Dominican Republic

593 Validation of palmar aquagenic wrinkling as an adjuvant for cystic fibrosis screening in the Dominican Republic

339 Diagnostic dilemmas in cystic fibrosis screen–positive infants with F191V and low sweat chloride

339 Diagnostic dilemmas in cystic fibrosis screen–positive infants with F191V and low sweat chloride

Identification of cystic fibrosis transmembrane conductance regulator gene (CFTR) variants: A retrospective study on the western and southern regions of Saudi Arabia.

To investigate the geographic distribution of common cystic fibrosis (CF) variants in the western and southern regions of Saudi Arabia. A retrospective study was conducted on 69 patients diagnosed with CF at King Faisal Specialist Hospital & Research Center, Jeddah. Patient data were collected retrospectively between June 2000 and November 2021. Various parameters were considered, including patient demographic information, CFTR variants, and respiratory cultures. We identified 26 CFTR variants in 69 patients with CF, including one novel variant that had not been reported or published before (1549del G) in 2 patients with CF. The 6 most prevalentvariants were as follows: c.1521_1523delCTT (19%), c.1418delG (10.2%), c.579+1G>T (8.8%), c.2988+1G>A (8.8%), c.3419T>A (7.2%), and c.4124A>C (5.8%). In addition, respiratory cultures revealed that Pseudomonas aeruginosa, Staphylococcus aureus, Haemophilus influenzae, and Streptococcus pneumoniae were highly common among patients with CF. This study highlighted features of patients with CF residing in the Western and Southern regions of Saudi Arabia. Six of the 26 CFTR variants were common in these patients. We also report, for the first time, a novel variant and other CFTR variants that are yet to be reported in Saudi Arabia. These findings could help establish a foundation for cystic fibrosis screening in Saudi Arabia and may assist in clinical diagnosis and prognosis.

Optimization of performance of Dutch newborn screening for cystic fibrosis

BackgroundDutch newborn screening (NBS) for Cystic Fibrosis (CF) introduced in 2011 showed a sensitivity of 90% and a positive predictive value (PPV) of 63%. We describe a study including an optimization phase and evaluation of the modified protocol. MethodsDutch protocol consists of four steps: determination of immunoreactive trypsinogen (IRT) and pancreatitis-associated protein (PAP), DNA analysis by INNO-LiPA and extended gene analysis (EGA).For the optimization phase we used results of 556,952 newborns screened between April 2011 and June 2014 to calculate effects of 13 alternative protocols on sensitivity, specificity, PPV, ratios of CF to other diagnoses, and costs. One alternative protocol was selected based on calculated sensitivity, PPV and costs and was implemented on 1st July 2016. In this modified protocol DNA analysis is performed in samples with a combination of IRT ≥60 µg/l and PAP ≥3.0 µg/l, IRT ≥100 µg/l and PAP ≥1.2 µg/l or IRT ≥124 µg/l and PAP not relevant. Results of 599,137 newborns screened between 1st July 2016 and 31st December 2019 were similarly evaluated as in the optimization phase. ResultsThe modified protocol showed a sensitivity of 95%, PPV of 76%, CF to CF transmembrane conductance regulator-related metabolic syndrome/CF screen positive, inconclusive diagnoses (CRMS/CFSPID) ratio 12/1, CF/CF carrier ratio 4/1. Costs per screened newborn were slightly higher. Eleven children, of whom five with classic CF, would not have been referred with the previous protocol. ConclusionsThe modified protocol results in acceptable sensitivity (95%) and good PPV of 76% with minimal increase in costs.

Neonatal Screening for Cystic Fibrosis in Hungary-First-Year Experiences.

The aim of this study is to evaluate the strategy of the cystic fibrosis newborn screening (CFNBS) programme in Hungary based on the results of the first year of screening. A combined immunoreactive trypsinogen (IRT) and pancreatitis-associated protein (PAP) CFNBS protocol (IRT/IRT×PAP/IRT) was applied with an IRT-dependent safety net (SN). Out of 88,400 newborns, 256 were tested screen-positive. Fourteen cystic fibrosis (CF) and two cystic fibrosis-positive inconclusive diagnosis (CFSPID) cases were confirmed from the screen-positive cases, and two false-negative cases were diagnosed later. Based on the obtained results, a sensitivity of 88% and a positive predictive value (PPV) of 5.9% were calculated. Following the recognition of false-negative cases, the calculation method of the age-dependent cut-off was changed. In purely biochemical CFNBS protocols, a small protocol change, even after a short period, can have a significant positive impact on the performance. CFNBS should be monitored continuously in order to fine-tune the screening strategy and define the best local practices.