Pathogens. 2021 Dec 18;10(12):1638. doi: 10.3390/pathogens10121638.

ABSTRACT

Pseudomonas aeruginosa is a major opportunistic pathogen, causing a wide range of acute and chronic infections. β-lactam antibiotics including penicillins, carbapenems, monobactams, and cephalosporins play a key role in the treatment of P. aeruginosa infections. However, a significant number of isolates of these bacteria are resistant to β-lactams, complicating treatment of infections and leading to worse outcomes for patients. In this review, we summarize studies demonstrating the health and economic impacts associated with β-lactam-resistant P. aeruginosa. We then describe how β-lactams bind to and inhibit P. aeruginosa penicillin-binding proteins that are required for synthesis and remodelling of peptidoglycan. Resistance to β-lactams is multifactorial and can involve changes to a key target protein, penicillin-binding protein 3, that is essential for cell division; reduced uptake or increased efflux of β-lactams; degradation of β-lactam antibiotics by increased expression or altered substrate specificity of an AmpC β-lactamase, or by the acquisition of β-lactamases through horizontal gene transfer; and changes to biofilm formation and metabolism. The current understanding of these mechanisms is discussed. Lastly, important knowledge gaps are identified, and possible strategies for enhancing the effectiveness of β-lactam antibiotics in treating P. aeruginosa infections are considered.

PMID:34959593 | DOI:10.3390/pathogens10121638

Pharmaceutics. 2021 Dec 1;13(12):2051. doi: 10.3390/pharmaceutics13122051.

ABSTRACT

Pulmonary infections caused by Pseudomonas aeruginosa (PA) represent the leading cause of pulmonary morbidity in adults with cystic fibrosis (CF). In addition to tobramycin, colistin, and aztreonam, levofloxacin has been approved in Europe to treat PA infections. Nevertheless, no lung deposition data on inhaled levofloxacin are yet available. We conducted a Functional Respiratory Imaging (FRI) study to predict the lung deposition of levofloxacin in the lungs of patients with CF. Three-dimensional airway models were digitally reconstructed from twenty high-resolution computed tomography scans obtained from historical patients' records. Levofloxacin aerosols generated with the corresponding approved nebuliser were characterised according to pharmacopeia. The obtained data were used to inform a computational fluid dynamics simulation of levofloxacin lung deposition using breathing patterns averaged from actual CF patients' spirometry data. Levofloxacin deposition in the lung periphery was significantly reduced by breathing patterns with low inspiratory times and high inspiratory flow rates. The intrathoracic levofloxacin deposition percentages for moderate and mild CF lungs were, respectively, 37.0% ± 13.6 and 39.5% ± 12.9 of the nominal dose. A significant albeit modest correlation was found between the central-to-peripheral deposition (C/P) ratio of levofloxacin and FEV1. FRI analysis also detected structural differences between mild and moderate CF airways. FRI revealed a significant intrathoracic deposition of levofloxacin aerosols, which distributed preferentially to the lower lung lobes, with an influence of the deterioration of FEV1 on the C/P ratio. The three-dimensional rendering of CF airways also detected structural differences between the airways of patients with mild and moderate CF.

PMID:34959333 | DOI:10.3390/pharmaceutics13122051

Pharmaceutics. 2021 Nov 30;13(12):2047. doi: 10.3390/pharmaceutics13122047.

ABSTRACT

An emergent approach to bacterial infection is the use of host rather than bacterial-directed strategies. This approach has the potential to improve efficacy in especially challenging infection settings, including chronic, recurrent infection due to intracellular pathogens. For nearly two decades, the pleiotropic effects of statin drugs have been examined for therapeutic usefulness beyond the treatment of hypercholesterolemia. Interest originated after retrospective studies reported decreases in the risk of death due to bacteremia or sepsis for those on a statin regimen. Although subsequent clinical trials have yielded mixed results and earlier findings have been questioned for biased study design, in vitro and in vivo studies have provided clear evidence of protective mechanisms that include immunomodulatory effects and the inhibition of host cell invasion. Ultimately, the benefits of statins in an infection setting appear to require attention to the underlying host response and to the timing of the dosage. From this examination of statin efficacy, additional novel host-directed strategies may produce adjunctive therapeutic approaches for the treatment of infection where traditional antimicrobial therapy continues to yield poor outcomes. This review focuses on the opportunistic pathogen, Staphylococcus aureus, as a proof of principle in examining the promise and limitations of statins in recalcitrant infection.

PMID:34959329 | DOI:10.3390/pharmaceutics13122047

Tuberk Toraks. 2021 Dec;69(4):520-534. doi: 10.5578/tt.20219610.

ABSTRACT

Macrolides are antibiotics with antiviral, anti-inflammatory and immunomodulatory effects in together with their bacteriostatic effects. In addition to its beneficial effects on chronic respiratory diseases such as COPD, cystic fibrosis, diffuse panbronchiolitis, and bronchiectasis, its effects on uncontrolled severe asthma and asthma exacerbations have been the subject of research in recent years. In randomized controlled trials, azithromycin, a macrolide, has been shown to reduce asthma exacerbations and significantly improve asthma-related quality of life in both eosinophilic and non-eosinophilic asthma phenotypes. However, there are also differences such as doses, durations and some studies not showing its effectiveness in severe eosinophilic asthma. In the GINA report, azithromycin can be recommended as an add-on therapy in patients with uncontrolled non-T2 severe asthma despite high-dose inhaled corticosteroid/ long-acting beta2-agonist/long-acting antimuscariniric treatments, or in T2 severe asthma patients whose asthma is not under control despite biologic therapy. In this review, the use of macrolides, especially azithromycin, in the treatment of asthma, immunomodulatory activities and safety profiles are discussed on the basis of current studies and guidelines.

PMID:34957746 | DOI:10.5578/tt.20219610

Adv Healthc Mater. 2021 Dec 27:e2102539. doi: 10.1002/adhm.202102539. Online ahead of print.

ABSTRACT

Lung infections caused by Gram-positive Staphylococcus aureus and co-infections caused by S. aureus and Gram-negative Pseudomonas aeruginosa are challenging to treat, especially with the rise in the number of antibiotic-resistant strains of these pathogens. Bacteriophage (phage) are bacteria-specific viruses that can infect and lyse bacteria, providing a potentially effective therapy for bacterial infections. However, the development of bacteriophage therapy is impeded by limited suitable biomaterials that can facilitate effective delivery of phage to the lung. Here, we demonstrate the ability of porous microparticles engineered from poly(lactic-co-glycolic acid) (PLGA), a biodegradable polyester, to effectively deliver phage to the lung. The phage-loaded microparticles (phage-MPs) display potent antimicrobial efficacy against various strains of S. aureus in vitro and in vivo, and arrest the growth of a clinical isolate of S. aureus in the presence of sputum supernatant obtained from cystic fibrosis patients. Moreover, phage-MPs efficiently mitigate in vitro co-cultures of S. aureus and P. aeruginosa and display excellent cytocompatibility with human lung epithelial cells. Therefore, phage-MPs represents a promising therapy to treat bacterial lung infection. This article is protected by copyright. All rights reserved.

PMID:34957709 | DOI:10.1002/adhm.202102539

Front Pharmacol. 2021 Dec 8;12:689205. doi: 10.3389/fphar.2021.689205. eCollection 2021.

ABSTRACT

Background: Cystic fibrosis (CF) is a genetic disease caused by mutations in CFTR, which encodes a chloride and bicarbonate transporter expressed in exocrine epithelia throughout the body. Recently, some therapeutics became available that directly target dysfunctional CFTR, yet research for more effective substances is ongoing. The database CandActCFTR aims to provide detailed and comprehensive information on candidate therapeutics for the activation of CFTR-mediated ion conductance aiding systems-biology approaches to identify substances that will synergistically activate CFTR-mediated ion conductance based on published data. Results: Until 10/2020, we derived data from 108 publications on 3,109 CFTR-relevant substances via the literature database PubMed and further 666 substances via ChEMBL; only 19 substances were shared between these sources. One hundred and forty-five molecules do not have a corresponding entry in PubChem or ChemSpider, which indicates that there currently is no single comprehensive database on chemical substances in the public domain. Apart from basic data on all compounds, we have visualized the chemical space derived from their chemical descriptors via a principal component analysis annotated for CFTR-relevant biological categories. Our online query tools enable the search for most similar compounds and provide the relevant annotations in a structured way. The integration of the KNIME software environment in the back-end facilitates a fast and user-friendly maintenance of the provided data sets and a quick extension with new functionalities, e.g., new analysis routines. CandActBase automatically integrates information from other online sources, such as synonyms from PubChem and provides links to other resources like ChEMBL or the source publications. Conclusion: CandActCFTR aims to establish a database model of candidate cystic fibrosis therapeutics for the activation of CFTR-mediated ion conductance to merge data from publicly available sources. Using CandActBase, our strategy to represent data from several internet resources in a merged and organized form can also be applied to other use cases. For substances tested as CFTR activating compounds, the search function allows users to check if a specific compound or a closely related substance was already tested in the CF field. The acquired information on tested substances will assist in the identification of the most promising candidates for future therapeutics.

PMID:34955819 | PMC:PMC8692862 | DOI:10.3389/fphar.2021.689205

J Cyst Fibros. 2021 Dec 23:S1569-1993(21)02152-4. doi: 10.1016/j.jcf.2021.11.011. Online ahead of print.

ABSTRACT

Exercise intolerance is common in people with CF (pwCF), but not universal among all individuals. While associated with disease prognosis, exercise intolerance is not simply a reflection of the degree of lung disease. In people with severe CF, respiratory limitations may contribute more significantly to impaired exercise capacity than in those with mild-moderate CF. At all levels of disease severity, there are peripheral factors e.g., abnormal macro- and micro-vascular function that impair blood flow and reduce oxygen extraction, and mitochondrial defects that diminish metabolic efficiency. We discuss advances in understanding the central and peripheral mechanisms underlying exercise intolerance in pwCF. Exploring both the central and peripheral factors that contribute to exercise intolerance in CF can help inform the development of new therapeutic targets, as well as help define prognostic criteria.

PMID:34955387 | DOI:10.1016/j.jcf.2021.11.011

Curr Opin Clin Nutr Metab Care. 2021 Dec 24. doi: 10.1097/MCO.0000000000000805. Online ahead of print.

ABSTRACT

PURPOSE OF REVIEW: Persistent unresolved inflammation results in a number of pathologic respiratory diseases including asthma, cystic fibrosis, acute respiratory distress syndrome (ARDS) and coronavirus disease 2019-associated ARDS. Inflammation resolution is an active series of biologic processes orchestrated by a family of bioactive specialized pro-resolving mediators (SPMs) derived from essential omega-3 and omega-6 polyunsaturated fatty acids (PUFAs). In this review, we highlight recent findings on dysregulated inflammation resolution in common respiratory diseases and recent literature on SPM generation with PUFA dietary supplementation with relevance to diseases of respiratory inflammation.

RECENT FINDINGS: Human studies and preclinical models of diseases of lung inflammation have revealed disequilibrium in the levels of pro-inflammatory versus pro-resolving mediators. Recent studies identified actions for SPMs on regulating prophlogistic host responses and stimulating inflammation resolution pathways in inflammatory respiratory diseases.

SUMMARY: Dietary marine oils are enriched in PUFAs and contain parent omega-3 and omega-6 fatty acids and precursors for conversion to SPMs. Nutritional supplementation with fish oils can boost SPM levels and offer a therapeutic approach targeting inflammation resolution pathways for diseases of lung inflammation.

PMID:34954726 | DOI:10.1097/MCO.0000000000000805

Microbes Infect. 2021 Dec 22:104928. doi: 10.1016/j.micinf.2021.104928. Online ahead of print.

ABSTRACT

Cationic antimicrobial peptides (CAMPs) are important actors in host innate immunity and represent a promising alternative to combat antibiotic resistance. Here, the bactericidal activity of two CAMPs (LL-37, and CAMA) was evaluated against Pseudomonas aeruginosa (PA) in the presence of IB3-1 cells, a cell line derived from patients with cystic fibrosis. The two CAMPs exerted different effects on PA survival depending on the timing of their administration. We observed a greater bactericidal effect when IB3-1 cells were pretreated with sub-minimum bactericidal concentrations (Sub-MBCs) of the CAMPs prior to infection. These findings suggest that CAMPs induce the production of factors by IB3-1 cells that improve their bactericidal action. However, we observed no bactericidal effect when supra-minimum bactericidal concentrations (Supra-MBCs) of the CAMPs were added to IB3-1 cells at the same time or after infection. Western-blot analysis showed a large decrease in LL-37 levels in supernatants of infected IB3-1 cells and an increase in LL-37 binding to these cells after LL-37 administration. LL-37 induced a weak inflammatory response in the cells without being toxic. In conclusion, our findings suggest a potential prophylactic action of CAMPs. The bactericidal effects were low when the CAMPs were added after cell infection, likely due to degradation of CAMPs by bacterial or epithelial cell proteases and/or due to adherence of CAMPs to cells becoming less available for direct bacterial killing.

PMID:34954126 | DOI:10.1016/j.micinf.2021.104928

J Pediatr (Rio J). 2021 Dec 22:S0021-7557(21)00169-8. doi: 10.1016/j.jped.2021.11.007. Online ahead of print.

ABSTRACT

OBJECTIVE: To present signs and symptoms and clinical course in cystic fibrosis patients with false-negative newborn screening (CF NBS).

MATERIALS AND METHODS: All children presented in this paper were covered by CF NBS. The group of 1.869.246 newborns was screened in the Institute of Mother and Child in Warsaw within a period of 01.01.1999 - 31.05.2019. Screening protocols evolved over time from IRT/IRT to IRT/DNA/EGA.

RESULTS: The authors identified 11 patients with false-negative NBS, in whom CF was diagnosed based on clinical symptoms or the examination of siblings with positive CF NBS. In the study group, the diagnosis was made significantly later in comparison to positive CF NBS patients ranging from 2 months to 15 years of age. CF NBS strategy does not significantly affect the sensitivity of the screening.

CONCLUSION: In the presence of clinical symptoms, additional diagnostics must be implemented, in spite of the negative screening results. At first, the sweat test should be conducted, followed by a DNA analysis of the most common mutations in the given population. The diagnostic process requires searching for CFTR mutations not typically associated with a high chloride concentration in sweat. Repetition of sweat chloride concentration enables the diagnosis in children whose initial chloride values in sweat are borderline, and no CF-causing mutations are detected. In strong clinical indications, the extension of DNA analysis (EGA) is recommended in order to identify rare CF variants. In children with meconium ileus, genetic analysis is mandatory.

PMID:34953776 | DOI:10.1016/j.jped.2021.11.007

J Cyst Fibros. 2021 Dec 22:S1569-1993(21)02171-8. doi: 10.1016/j.jcf.2021.10.014. Online ahead of print.

ABSTRACT

BACKGROUND: Cystic fibrosis (CF)-associated liver disease (CFLD) causes significant morbidity and mortality in children with CF. Diagnosis of liver disease prior to development of cirrhosis or portal hypertension (PHT) is challenging. While imaging modalities using Elastography show great promise they are still not widely available to all clinicians. This study investigated gamma-glutamyl transpeptidase-to-platelet ratio (GPR) as a non-invasive biomarker to detect liver disease and stage fibrosis severity in children with CF.

METHODS: 237 children were enroled including 76 with CFLD and 161 with CF and no detectable liver disease (CFnoLD). CFLD was diagnosed using standard clinical, biochemical and imaging practice guidelines. Hepatic fibrosis was staged on liver biopsies available from 54 children with CFLD. Serum liver biochemistry was used to calculate GPR (median, [IQR]) and receiver operating characteristics (ROC) analysis assessed utility to detect liver disease and stage fibrosis severity.

RESULTS: GPR was significantly increased in CFLD versus CFnoLD (0.33 [0.19-0.96] vs. 0.15 [0.11-0.21], P<0.0001). GPR demonstrated good diagnostic utility for detecting CFLD with an area under the curve (AUC) of 0.81 (95% confidence Interval [CI] [0.75-0.87]; P<0.0001), with sensitivity of 74% and specificity of 73%, using a cut-off of 0.20. GPR increased with increasing hepatic fibrosis stage. GPR discriminated both moderate-advanced (F2-F4) fibrosis vs. F0-F1 (AUC=0.82; 95%CI [0.71-0.94]; P<0.0001) and advanced (F3-F4) fibrosis vs. F0-F2 (AUC=0.77; 95%CI [0.64-0.90]; P = 0.004), with a cut-off 0.32 and 0.61, respectively. An elevated GPR of >0.84 was predictive of PHT at diagnosis of CFLD (AUC=0.81; 95%CI [0.67-0.95]; P = 0.0003).

CONCLUSIONS: GPR demonstrates good diagnostic utility for assessing the presence of liver disease, PHT and hepatic fibrosis severity in children with CF. These findings will aid in better identification of patients at risk for CF-related liver involvement and the potential for more targeted and timely follow-up and treatment.

PMID:34953741 | DOI:10.1016/j.jcf.2021.10.014

J Pediatr Nurs. 2021 Nov 16:S0882-5963(21)00325-0. doi: 10.1016/j.pedn.2021.11.006. Online ahead of print.

ABSTRACT

BACKGROUND: The COVID-19 pandemic necessitated immediate transition from in person to telehealth encounters; novel nursing practices were needed to ensure that children with cystic fibrosis (CF) receive care that approximates evidence-based guidelines.

LOCAL PROBLEM: The aim was to ensure that as many children as possible received routine surveillance of pulmonary pathogens by a CF culture sputum culture during a pandemic.

METHODS: Multiple Plan-Do-Study-Act (PDSA) cycles were utilized to implement practice change over four months.

INTERVENTIONS: Cultures were obtained via curbside appointment with a registered nurse (RN) or at the patients' home with mailed equipment.

RESULTS: 133 cultures obtained: 50.37% (67) by RN collection curbside and 49.62% (66) by self/caregiver at home. 120 culture swabs or sterile cups were mailed; 55% (66) were returned. Cost of mailing equipment was $760.16.

CONCLUSION: Nursing utilization of PDSA cycles developed novel processes that ensured guideline-based care during the initial months of the pandemic.

PMID:34953664 | DOI:10.1016/j.pedn.2021.11.006

J Pediatr Nurs. 2021 Dec 22:S0882-5963(21)00375-4. doi: 10.1016/j.pedn.2021.12.007. Online ahead of print.

ABSTRACT

PURPOSE: Cystic fibrosis is a life-shortening genetic disease. It affects both patient and family with the nurse playing a key role in the monitoring process. This study sought to contribute to enhanced targeted health care to adolescents with cystic fibrosis and their parents by understanding the experiences of living with cystic fibrosis. Based on Afaf Meleis' Transitions Theory (1986) nurses identify the transition experienced by the study participants, thus contributing to the quality of nursing interventions.

DESIGN AND METHODS: Two qualitative research studies using data collected through semi-structured interviews were conducted. The Straussian Grounded Theory was applied. The snowball technique was used for recruitment, under the inclusion criteria: adolescents aged between 10 and 21 years; diagnosis of cystic fibrosis for more than one year; and parents of these adolescents. A final sample of 16 adolescents and 14 parents was obtained.

RESULTS: Nursing therapeutic interventions acted as a facilitator of the health/illness transition process. Nurses' intervention areas were identified to empower adolescents and their parents with targeted knowledge and abilities to cope with problems. After diagnosis, parents assumed a new role-playing.

CONCLUSIONS: Adolescents with cystic fibrosis and their parents experience various transition phases. Nurses can better help identifying the onset, persistence and ending of harmful periods.

PRACTICE IMPLICATIONS: Adolescents with cystic fibrosis and their parents experience various transition phases. Nursing therapeutic interventions are cardinal to the health/illness transition.

PMID:34953662 | DOI:10.1016/j.pedn.2021.12.007

J Med Genet. 2021 Dec 24:jmedgenet-2021-108150. doi: 10.1136/jmedgenet-2021-108150. Online ahead of print.

ABSTRACT

PURPOSE: We sought to describe a disorder clinically mimicking cystic fibrosis (CF) and to elucidate its genetic cause.

METHODS: Exome/genome sequencing and human phenotype ontology data of nearly 40 000 patients from our Bio/Databank were analysed. RNA sequencing of samples from the nasal mucosa from patients, carriers and controls followed by transcriptome analysis was performed.

RESULTS: We identified 13 patients from 9 families with a CF-like phenotype consisting of recurrent lower respiratory infections (13/13), failure to thrive (13/13) and chronic diarrhoea (8/13), with high morbidity and mortality. All patients had biallelic variants in AGR2, (1) two splice-site variants, (2) gene deletion and (3) three missense variants. We confirmed aberrant AGR2 transcripts caused by an intronic variant and complete absence of AGR2 transcripts caused by the large gene deletion, resulting in loss of function (LoF). Furthermore, transcriptome analysis identified significant downregulation of components of the mucociliary machinery (intraciliary transport, cilium organisation), as well as upregulation of immune processes.

CONCLUSION: We describe a previously unrecognised autosomal recessive disorder caused by AGR2 variants. AGR2-related disease should be considered as a differential diagnosis in patients presenting a CF-like phenotype. This has implications for the molecular diagnosis and management of these patients. AGR2 LoF is likely the disease mechanism, with consequent impairment of the mucociliary defence machinery. Future studies should aim to establish a better understanding of the disease pathophysiology and to identify potential drug targets.

PMID:34952832 | DOI:10.1136/jmedgenet-2021-108150

BMC Pulm Med. 2021 Dec 24;21(1):425. doi: 10.1186/s12890-021-01789-9.

ABSTRACT

BACKGROUND: Allergic bronchopulmonary aspergillosis (ABPA) is a bronchopulmonary disease caused by a complex hypersensitivity to Aspergillus and is usually associated with underlying respiratory diseases such as asthma or cystic fibrosis. Mucus plugging can lead to segmental or lobar atelectasis, but complete lung atelectasis has been exceptionally reported in the literature, making it difficult to diagnose. The diagnosis of ABPA may however be suggested in patients without known predisposing respiratory disorder, even in the absence of other relevant radiographic findings.

CASE PRESENTATION: We report five cases of total unilateral lung collapse secondary to ABPA in 70-81-year-old women. Two of them had a past history of ABPA, while total unilateral lung collapse was the first sign of the disease in the other three patients, contributing to the initial misdiagnosis. Flexible bronchoscopy was initially performed to remove mucus plugs from the obstructed airways but was inefficient in four cases. Corticosteroid and/or antifungal treatment was needed.

CONCLUSION: ABPA can cause total unilateral lung collapse even in patients without known underlying chronic respiratory disease, making the diagnosis difficult. Flexible bronchoscopy should be considered when lung collapse is associated with respiratory distress but corticosteroids are the mainstay treatment for ABPA.

PMID:34952578 | DOI:10.1186/s12890-021-01789-9

Front Immunol. 2021 Dec 7;12:714027. doi: 10.3389/fimmu.2021.714027. eCollection 2021.

ABSTRACT

In the coronavirus disease 2019 (COVID-19) health crisis, one major challenge is to identify the susceptibility factors of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) in order to adapt the recommendations for populations, as well as to reduce the risk of COVID-19 development in the most vulnerable people, especially patients with chronic respiratory diseases such as cystic fibrosis (CF). Airway epithelial cells (AECs) play a critical role in the modulation of both immune responses and COVID-19 severity. SARS-CoV-2 infects the airway through the receptor angiotensin-converting enzyme 2, and a host protease, transmembrane serine protease 2 (TMPRSS2), plays a major role in SARS-CoV-2 infectivity. Here, we show that Pseudomonas aeruginosa increases TMPRSS2 expression, notably in primary AECs with deficiency of the ion channel CF transmembrane conductance regulator (CFTR). Further, we show that the main component of P. aeruginosa flagella, the protein flagellin, increases TMPRSS2 expression in primary AECs and Calu-3 cells, through activation of Toll-like receptor-5 and p38 MAPK. This increase is particularly seen in Calu-3 cells deficient for CFTR and is associated with an intracellular increased level of SARS-CoV-2 infection, however, with no effect on the amount of virus particles released. Considering the urgency of the COVID-19 health crisis, this result may be of clinical significance for CF patients, who are frequently infected with and colonized by P. aeruginosa during the course of CF and might develop COVID-19.

PMID:34950129 | PMC:PMC8688244 | DOI:10.3389/fimmu.2021.714027

BMJ Open Respir Res. 2021 Dec;8(1):e001106. doi: 10.1136/bmjresp-2021-001106.

ABSTRACT

RATIONALE: The airway microbiota is important in chronic suppurative lung diseases, such as primary ciliary dyskinesia (PCD) and cystic fibrosis (CF). This comparison has not previously been described but is important because difference between the two diseases may relate to the differing prognoses and lead to pathological insights and potentially, new treatments.

OBJECTIVES: To compare the longitudinal development of the airway microbiota in children with PCD to that of CF and relate this to age and clinical status.

METHODS: Sixty-two age-matched children (age range 0.5-17 years) with PCD or CF (n=31 in each group) were recruited prospectively and followed for 1.1 years. Throat swabs or sputum as well as clinical information were collected at routine clinical appointments. 16S rRNA gene sequencing was performed.

MEASUREMENTS AND MAIN RESULTS: The microbiota was highly individual and more diverse in PCD and differed in community composition when compared with CF. While Streptococcus was the most abundant genus in both conditions, Pseudomonas was more abundant in CF with Haemophilus more abundant in PCD (Padj=0.0005). In PCD only, an inverse relationship was seen in the relative abundance of Streptococcus and Haemophilus with age.

CONCLUSIONS: Bacterial community composition differs between children with PCD and those with CF. Pseudomonas is more prevalent in CF and Haemophilus in PCD, at least until infection with Pseudomonas supervenes. Interactions between organisms, particularly members of Haemophilus, Streptococcus and Pseudomonas genera appear important. Study of the interactions between these organisms may lead to new therapies or risk stratification.

PMID:34949574 | DOI:10.1136/bmjresp-2021-001106

J Cyst Fibros. 2021 Dec 13:S1569-1993(21)02170-6. doi: 10.1016/j.jcf.2021.12.011. Online ahead of print.

ABSTRACT

The prevalence of anti-SARS-CoV-2 antibodies in people with cystic fibrosis (CF) is largely unknown. We carried out a cross-sectional study between March and June 2021 with the aim of estimating the seroprevalence of anti-SARS-CoV-2 antibodies in two CF centres in Northern Italy. Total serum anti-SARS-CoV-2 (spike) antibodies levels were measured and values ≥0.8 U/mL were considered positive. Among 434 patients aged >12 years, 64 patients had a positive result (14.7%, 95% CI: 11.5-18.4), 36 (56.3%) without experiencing any COVID-19-related symptoms. Three out of 49 transplanted patients tested positive with an odds ratio for a positive result among transplanted as compared to non-transplanted patients of 0.35 (95% CI: 0.07-1.14). No significant differences were observed between sexes, age groups, socioeconomic status and lung disease severity. In conclusion, SARS-CoV-2 has infected a relatively high proportion of our patients but in most cases the infection was asymptomatic.

PMID:34949558 | DOI:10.1016/j.jcf.2021.12.011

J Cyst Fibros. 2021 Dec 20:S1569-1993(21)02162-7. doi: 10.1016/j.jcf.2021.12.002. Online ahead of print.

ABSTRACT

PURPOSE: We examined cystic fibrosis (CF) patients and compared their clinical status at the time of primary versus double lung re-transplantation (re-DLTx) in order to better understand lung retransplant practice patterns.

METHODS: We performed a retrospective analysis of the UNOS Database identifying CF patients ≥18 years old undergoing re-DLTx (5/4/2005 and 12/4/2020). Baseline and clinical variables at the primary and re-DLTx were compared utilizing the paired student t-test. Graft survival was defined as time from surgery to retransplant and analyzed using Kaplan-Meier estimates.

RESULTS: 277 CF patients who underwent re-DLTx experienced a significantly worse 5-year survival when compared to the primary DLTx cohort (47.9% vs 58.8%, p = 0.00012). The following differences were observed comparing CF re-DLTx group to their primary DLTx: higher LAS score at the time of listing (50.66 vs 42.15, p < 0.001) and transplant (62.19 vs 48.20, p < 0.001), and increase LAS from the time of listing to transplant (+12.22 vs +7.23, p = 0.002). While serum albumin and total bilirubin were similar, CF patients had a higher creatinine (1.05 vs 0.74, p < 0.001), dialysis (4.4% vs 0.6%, p < 0.001), ECMO bridge to transplant rates (7.6% vs 4.0%, p < 0.001), and higher oxygen requirements (5.95 vs 3.93, p < 0.001) at the time of listing for a re-DLTx.

CONCLUSION: Compared to their initial transplant, CF patients experience significant clinical decline in renal, cardiac, and pulmonary function at the time of lung retransplantation. This may indicate that an earlier evaluation and rehabilitation process may be necessary to identify patients earlier for lung retransplantation prior significant clinical decline.

PMID:34949557 | DOI:10.1016/j.jcf.2021.12.002

J Cyst Fibros. 2021 Dec 20:S1569-1993(21)02169-X. doi: 10.1016/j.jcf.2021.12.010. Online ahead of print.

ABSTRACT

BACKGROUND: Newborn screening for Cystic Fibrosis (CF) is associated with situations where the diagnosis of CF or CFTR related disorders (CFTR-RD) cannot be clearly ruled out.

MATERIALS/PATIENTS AND METHODS: We report a case series of 23 children with unconclusive diagnosis after newborn screening for CF and a mean follow-up of 7.7 years (4-13). Comprehensive investigations including whole CFTR gene sequencing, in vivo intestinal current measurement (ICM), nasal potential difference (NPD), and in vitro functional studies of variants of unknown significance, helped to reclassify the patients.

RESULTS: Extensive genetic testing identified, in trans with a CF causing mutation, variants with varying clinical consequences and 3 variants of unknown significance (VUS). Eighteen deep intronic variants were identified by deep resequencing of the whole CFTR gene in 13 patients and were finally considered as non-pathogenic. All patients had normal CFTR dependent chloride transport in ICM. NPD differentiated 3 different profiles: CF-like tracings qualifying the patients as CF, such as F508del/D1152H patients; normal responses, suggesting an extremely low likelihood of developing a CFTR-RD such as F508del/TG11T5 patients; partial CFTR dysfunction above 20% of the normal, highlighting a remaining risk of developing CFTR-RD such as F508del/F1052V patients. The 3 VUS were reclassified as variant with defective maturation (D537N), defective expression (T582I) or with no clinical consequence (M952T).

CONCLUSION: This study demonstrates the usefulness of combining genetic and functional investigations to assess the possibility of evolving to CF or CFTR-RD in babies with inconclusive diagnosis at neonatal screening.

PMID:34949556 | DOI:10.1016/j.jcf.2021.12.010