Ann Am Thorac Soc. 2022 Nov;19(11):1799-1801. doi: 10.1513/AnnalsATS.202208-703ED.

NO ABSTRACT

PMID:36318079 | DOI:10.1513/AnnalsATS.202208-703ED

Ann Intern Med. 2022 Nov 1. doi: 10.7326/M22-1741. Online ahead of print.

ABSTRACT

BACKGROUND: In cystic fibrosis (CF), renal base excretion is impaired. Accordingly, challenged urine bicarbonate excretion may be an in vivo biomarker of cystic fibrosis transmembrane conductance regulator (CFTR) function.

OBJECTIVE: To evaluate the association between challenged bicarbonate excretion and clinical characteristics at baseline, quantify the CFTR modulator drug elexacaftor/tezacaftor/ivacaftor-induced changes of challenged bicarbonate excretion after 6 months of treatment, and characterize the intraindividual variation in healthy adults.

DESIGN: Prospective observational study.

SETTING: Cystic fibrosis clinic, Aarhus University Hospital, Denmark.

PATIENTS: Fifty adult patients with CF starting CFTR modulator therapy with elexacaftor/tezacaftor/ivacaftor between May 2020 and June 2021.

MEASUREMENTS: Quantification of urine bicarbonate excretion after an acute oral sodium bicarbonate challenge before and 6 months after elexacaftor/tezacaftor/ivacaftor treatment.

RESULTS: At baseline, challenged urine bicarbonate excretion was associated with several CF disease characteristics. Bicarbonate excretion was higher in patients with residual function mutations. A higher bicarbonate excretion was associated with better lung function, pancreatic sufficiency, and lower relative risk for chronic pseudomonas infections. Elexacaftor/tezacaftor/ivacaftor treatment increased bicarbonate excretion by 3.9 mmol/3 h (95% CI, 1.6 to 6.1 mmol/3 h), reaching about 70% of that seen in healthy control participants. In healthy control participants, individual bicarbonate excretion at each visit correlated with the individual mean bicarbonate excretion. The median coefficient of variation was 31%.

LIMITATION: Single-center study without a placebo-controlled group.

CONCLUSION: Although further studies are needed to address the performance and sensitivity of this approach, this early-stage evaluation shows that challenged urine bicarbonate excretion may offer a new, simple, and safe quantification of CFTR function and the extent of its pharmacologic improvement. Elexacaftor/tezacaftor/ivacaftor partially restores renal CFTR function in patients with CF, likely resulting in decreased risk for electrolyte disorders and metabolic alkalosis.

PRIMARY FUNDING SOURCE: Innovation Fund Denmark.

PMID:36315944 | DOI:10.7326/M22-1741

Pediatr Pulmonol. 2022 Oct 31. doi: 10.1002/ppul.26217. Online ahead of print.

ABSTRACT

We report a case series of four patients with cystic fibrosis (CF) and previous solid organ transplantation (SOT) receiving elexacaftor/tezacaftor/ivacaftor therapy for six months or more. This article is protected by copyright. All rights reserved.

PMID:36314653 | DOI:10.1002/ppul.26217

Pediatr Pulmonol. 2022 Oct 31. doi: 10.1002/ppul.26216. Online ahead of print.

ABSTRACT

BACKGROUND: Pulmonary disease is the leading cause of morbidity and mortality in people with Cystic fibrosis (pwCF). Several studies have shown no benefit for bronchoscopy and bronchoalveolar lavage (BAL) over sputum to obtain microbiological cultures, hence the role of bronchoscopy in pwCF is unclear.

AIM: To analyze how bronchoscopy results affected clinical decision-making in pwCF and assess safety.

METHODS: A retrospective analysis of all charts of pwCF from three CF centers in Israel, between the years 2008-2019. We collected BAL culture results as well as sputum cultures obtained within 1 month of the BAL sample. A meaningful yield was defined as a decision to start antibiotics, change the antibiotic regimen, hospitalize the patient for treatment, or the resolution of the problem that led to bronchoscopy (e.g. atelectasis or hemoptysis).

RESULTS: During the study years, of the 428 consecutive patient charts screened, 72 patients had 154 bronchoscopies (2.14 bronchoscopies/patient). Forty-five percent of the bronchoscopies had a meaningful clinical yield. The finding of copious sputum on bronchoscopy was strongly associated with a change in treatment (OR: 5.25, CI95%: 2.1-13.07, P<0.001). BAL culture results were strongly associated with a meaningful yield, specifically isolation of Aspergillus spp. (P=0.003), H. Influenza (P=0.001). Eight minor adverse events following bronchoscopy were recorded.

CONCLUSIONS: In this multicenter retrospective analysis of bronchoscopy procedures from three CF centers, we have shown that a significant proportion of bronchoscopies led to a change in treatment, with no serious adverse events. Our findings suggest that bronchoscopy is a safe procedure that may assist in guiding treatment in some pwCF. Future studies should evaluate whether BAL-guided decision-making may also lead to a change in clinical outcomes in pwCF. This article is protected by copyright. All rights reserved.

PMID:36314650 | DOI:10.1002/ppul.26216

Front Endocrinol (Lausanne). 2022 Oct 13;13:992667. doi: 10.3389/fendo.2022.992667. eCollection 2022.

ABSTRACT

Cystic fibrosis (CF), which is the most common inherited genetically determined disease caused by a mutation in the gene for the CF transmembrane conductance regulator protein. Pulmonary failure is the leading cause of death in this population, while the dysregulation of endocrine system creates significant disorders, including malnutrition, underweight, and CF-related diabetes. Therefore, the objective of our study was to determine the following hormones in the serum of patients with CF: ghrelin, putative peptide YY (PYY), Agouti-signaling protein (ASP), and alpha-melanocyte-stimulating hormone (α-MSH). To our knowledge, serum levels of PYY, ASP, and α-MSH have not yet been assessed in CF. For this purpose, we measured hormone levels using enzyme-linked immunosorbent assays in 38 patients from the local CF care center, as well as 16 sex- and age-matched healthy controls. Moreover, we estimated the correlations between the tested hormones and the parameters of the patients' clinical status. In this study, we found sinificantly reduced serum levels of ghrelin and ASP in patients with CF (p<0.01). There was no difference in PYY and α-MSH levels between participants with CF and healthy subjects. Furthermore, there was no difference in hormone levels between females and males with CF. The type of gene mutation (homozygous or heterozygous for ΔF508) had no effect on hormone levels. Ghrelin was negatively correlated with age, body mass index, and C-reactive protein. PYY was negatively associated with the age of the patients. Hormone dysregulation in CF may contribute to decreased appetite, as well as many other disturbed processes. Therefore, ghrelin appears to play a key role in the regulation of energy management of CF. Future multicenter and multidisciplinary studies should focus on an unequivocal understanding of the role of these hormones in CF.

PMID:36313742 | PMC:PMC9606394 | DOI:10.3389/fendo.2022.992667

Front Microbiol. 2022 Oct 13;13:975883. doi: 10.3389/fmicb.2022.975883. eCollection 2022.

ABSTRACT

Microorganisms proteotyping by tandem mass spectrometry has been recently shown as a powerful methodology to identify the wide-range taxonomy and biomass of microbiota. Sputum is the recommended specimen for routine microbiological monitoring of Cystic Fibrosis (CF) patients but has been rarely submitted to tandem mass spectrometry-based proteotyping. In this study, we compared the microbial components of spontaneous and induced sputum samples from three cystic fibrosis patients. Although the presence of microbial proteins is much lower than host proteins, we report that the microbiota's components present in the samples can be identified, as well as host biomarkers and functional insights into the microbiota. No significant difference was found in microorganism abundance between paired spontaneous and induced sputum samples. Microbial proteins linked to resistance, iron uptake, and biofilm-forming ability were observed in sputa independently of the sampling method. This unbiased and enlarged view of the CF microbiome could be highly complementary to culture and relevant for the clinical management of CF patients by improving knowledge about the host-pathogen dynamics and CF pathophysiology.

PMID:36312921 | PMC:PMC9608366 | DOI:10.3389/fmicb.2022.975883

Cureus. 2022 Sep 25;14(9):e29552. doi: 10.7759/cureus.29552. eCollection 2022 Sep.

ABSTRACT

Allergic bronchopulmonary aspergillosis (ABPA) is a fungal hypersensitivity reaction in chronic lung diseases like bronchial asthma and cystic fibrosis. It is caused by an allergic reaction to aspergillus antigen in the lung mucus resulting in airway inflammation and damage. This condition usually presents in a patient with asthma as a poorly controlled disease with recurrent infection symptoms that do not respond to standard antibiotic therapy. Diagnosis is made by chest X-ray, computed tomography, eosinophilia, and raised serum IgE on serology and immunological tests for aspergillus antigen. Lack of diagnosis and treatment of the condition can lead to respiratory failure from bronchiectasis and pulmonary fibrosis.

PMID:36312634 | PMC:PMC9595235 | DOI:10.7759/cureus.29552

Sci Rep. 2022 Oct 29;12(1):18243. doi: 10.1038/s41598-022-23082-3.

ABSTRACT

The microbiological safety of medical devices is of paramount importance for patients and manufacturers alike. However, during usage medical devices will inevitably become contaminated with microorganisms, including opportunistic pathogens. This is a particular problem if these devices come in contact with body sites that carry high bacterial loads, such as the oral cavity. In the present study, we investigated whether high oxygen concentrations can be applied to disinfect surfaces contaminated with different Gram-positive and Gram-negative bacteria. We show that some opportunistic pathogens, exemplified by Pseudomonas aeruginosa, are particularly sensitive to oxygen concentrations above the atmospheric oxygen concentration of 21%. Our observations also show that high oxygen concentrations can be applied to reduce the load of P. aeruginosa on nebulizers that are used by cystic fibrosis patients, who are particularly susceptible to colonization and infection by this bacterium. We conclude that the efficacy of oxygen-mediated disinfection depends on the bacterial species, duration of oxygen exposure and the oxygen concentration. We consider these observations relevant, because gas mixtures with high oxygen content can be readily applied for microbial decontamination. However, the main challenge for oxygen-based disinfection approaches resides in a potentially incomplete elimination of microbial contaminants, which makes combined usage with other disinfectants like ethanol or hydrogen peroxide recommendable.

PMID:36309557 | DOI:10.1038/s41598-022-23082-3

In Vivo. 2022 Nov-Dec;36(6):2993-2998. doi: 10.21873/invivo.13044.

ABSTRACT

BACKGROUND/AIM: Bronchiectasis has long been neglected, unlike chronic obstructive pulmonary disease (COPD) and asthma. Recent clinical trials have shown that long-term use of azithromycin or erythromycin reduce exacerbations of non-cystic fibrosis (non-CF) bronchiectasis. Because of this, we should actively try to treat patients susceptible to severe status.

PATIENTS AND METHODS: We enrolled patients who had been diagnosed with bronchiectasis at five branches of the Catholic Medical Center between January 2015 to December 2017. We retrospectively analyzed these patients for demographic characteristics such as sex, age, body mass index (BMI), history of smoking and tuberculosis, bacterial colonization, pulmonary function, hospitalizations, and other exacerbations.

RESULTS: Colonization was shown to have a statistically significant association with hospitalization. A three-year follow up period showed that the mean frequency of hospitalization in patients without colonization was 0.8 times, compared to 0.7 times and 1.9 times, respectively in patients with NTM colonization and with other bacterial colonization (p-value=0.03). Patients with a lower BMI also had an increased risk of hospitalization (p-value=0.024). Current smokers had increased risk of mortality as compared to those who had never smoked (HR=11.29, p-value 0.015). Patients with a high BMI also had low risk of mortality as compared to patients with a low BMI (HR=0.76, p-value 0.005).

CONCLUSION: Patients with bronchiectasis having chronic colonization, low BMI, or who are current smokers tend to be at greater risk for severe illness. Therefore, physicians should actively treat these patients to prevent exacerbations and mortality.

PMID:36309393 | DOI:10.21873/invivo.13044

J Hosp Infect. 2022 Oct 26:S0195-6701(22)00339-5. doi: 10.1016/j.jhin.2022.10.008. Online ahead of print.

ABSTRACT

BACKGROUND: Mycobacterium abscessus (MABS) group are environmental organisms that can cause infection in people with cystic fibrosis (CF) and other suppurative lung diseases. There is potential for person-to-person airborne transmission of MABS among people with CF attending the same care centre. Ultraviolet light (band C, UV-C) is used for Mycobacterium tuberculosis control indoors, however, no studies have assessed UV-C for airborne MABS.

AIM: We aimed to determine if a range of UV-C doses increased the inactivation of airborne MABS, compared with no-UVC conditions.

METHODS: MABS was generated by a vibrating mesh nebulizer located within a 400 L rotating drum sampler, and then exposed to an array of 265 nm UV-C light emitting diodes (LED). A six-stage Andersen Cascade Impactor was used to collect aerosols. We used standard microbiological protocols for enumerating MABS, and quantified the effectiveness of UV-C doses (in triplicate). UV-C effectiveness was estimated using the difference between inactivation with and without UV-C.

FINDINGS: Sixteen tests were performed, with UV-C doses ranging from 276 to 1104 μW s/cm2. Mean (± SD) UV-C effectiveness ranged from 47.1% (±13.4) to 83.6% (±3.3). UV-C led to significantly greater inactivation of MABS (all p-values ≤0.045) than natural decay at all doses assessed. Using an indoor model of the hospital environment, we estimated that UV-C doses in the range we studied could be safely delivered in clinical settings where patients and staff are present.

CONCLUSION: This study provides empirical in-vitro evidence that nebulized MABS are susceptible to UV-C inactivation.

PMID:36309203 | DOI:10.1016/j.jhin.2022.10.008

Eur J Pharmacol. 2022 Oct 26:175349. doi: 10.1016/j.ejphar.2022.175349. Online ahead of print.

ABSTRACT

The latest studies identified the histone deacetylase (HDAC) class of enzymes as strategic components of the complex molecular machinery underlying inflammation in cystic fibrosis (CF). Compelling new support has been provided for HDAC6 isoform as a key player in the generation of the dysregulated proinflammatory phenotype in CF, as well as in the immune response to the persistent bacterial infection accompanying CF patients. We herein provide in vivo proof-of-concept (PoC) of the efficacy of selective HDAC6 inhibition in contrasting the pro-inflammatory phenotype in a mouse model of chronic P. aeruginosa respiratory infection. Upon careful selection and in-house re-profiling (in vitro and cell-based assessment of acetylated tubulin level through Western blot analysis) of three potent and selective HDAC6 inhibitors as putative candidates for the PoC, we engaged the best performing compound 2 for pre-clinical studies. Compound 2 demonstrated no toxicity and robust anti-inflammatory profile in a mouse model of chronic P. aeruginosa respiratory infection upon repeated aerosol administration. A significant reduction of leukocyte recruitment in the airways, in particular neutrophils, was observed in compound 2-treated mice in comparison with the vehicle; moreover, quantitative immunoassays confirmed a significant reduction of chemokines and cytokines in lung homogenate. This effect was also associated with a modest reduced bacterial load after compound 2-treatment in mice compared to the vehicle. Our study is of particular significance since it demonstrates for the first time the utility of selective drug-like HDAC6 inhibitors in a relevant in vivo model of chronic P. aeruginosa infection, thus supporting their potential application for reverting CF phenotype.

PMID:36309047 | DOI:10.1016/j.ejphar.2022.175349

Pediatr Radiol. 2022 Oct 29. doi: 10.1007/s00247-022-05522-4. Online ahead of print.

ABSTRACT

Imaging plays a pivotal role in the noninvasive assessment of cystic fibrosis (CF)-related lung damage, which remains the main cause of morbidity and mortality in children with CF. The development of new imaging techniques has significantly changed clinical practice, and advances in therapies have posed diagnostic and monitoring challenges. The authors summarise these challenges and offer new perspectives in the use of imaging for children with CF for both clinicians and radiologists. This article focuses on chest radiography and CT, which are the two main radiologic techniques used in most cystic fibrosis centres. Advantages and disadvantages of radiography and CT for imaging in CF are described, with attention to new developments in these techniques, such as the use of artificial intelligence (AI) image analysis strategies to improve the sensitivity of radiography and CT and the introduction of the photon-counting detector CT scanner to increase spatial resolution at no dose expense.

PMID:36307546 | DOI:10.1007/s00247-022-05522-4

Trends Immunol. 2022 Oct 25:S1471-4906(22)00229-0. doi: 10.1016/j.it.2022.10.008. Online ahead of print.

ABSTRACT

Endoplasmic reticulum stress can stimulate calreticulin (CALR) presentation on the cell surface, promoting the phagocytic uptake of stressed cells by myeloid cells. Recent findings from Wattrus et al. demonstrate that zebrafish and mouse embryonic macrophages engulf CALR-exposing nascent hematopoietic stem cells to ensure the selective survival of stem cells apt for adult hematopoiesis.

PMID:36307308 | DOI:10.1016/j.it.2022.10.008

J Allergy Clin Immunol. 2022 Oct 25:S0091-6749(22)01416-6. doi: 10.1016/j.jaci.2022.09.034. Online ahead of print.

ABSTRACT

BACKGROUND: Alternaria alternata and house dust mite (HDM) exposure evokes interleukin-33 secretion from the airway epithelium, which functions as an alarmin to stimulate type 2 immunity. Extracellular DNA (eDNA) is also an alarmin that intensifies inflammation in cystic fibrosis, chronic obstructive pulmonary disease (COPD) and asthma.

OBJECTIVE: Investigate mechanisms underlying allergen-evoked DNA mobilization and release from the airway epithelium and determine the role of eDNA in type 2 immunity.

METHODS: Human bronchial epithelial (hBE) cells were used to characterize allergen-induced DNA mobilization and extracellular release using comet assays to measure DNA fragmentation, Qubit® dsDNA assays to measure DNA release and DNA sequencing to determine eDNA composition. Mice were used to investigate the role of eDNA in type 2 immunity.

RESULTS: Alternaria extract rapidly induces mitochondrial (mtDNA) and nuclear DNA (nDNA) release from hBE cells, whereas HDM extract induces mtDNA release. Caspase 3 is responsible for nDNA fragmentation and becomes activated following cleavage by furin. Analysis of secreted nDNA showed disproportionally higher amounts of promotor and exon sequences and lower intron and intergenic regions compared to predictions of random DNA fragmentation. In mice, Alternaria-induced type 2 immune responses were blocked by pretreatment with a DNA scavenger. In caspase 3 deficient mice, Alternaria-induced DNA release was suppressed. Furthermore, intranasal administration of mouse genomic DNA with Alternaria amplified secretion of IL-5 and IL-13 into bronchoalveolar lavage (BAL) fluid while DNA alone had no effect.

CONCLUSION: These findings highlight a novel, allergen-induced mechanism of rapid DNA release that amplifies type 2 immunity in airways.

PMID:36306937 | DOI:10.1016/j.jaci.2022.09.034

Turk J Pediatr. 2022;64(5):848-858. doi: 10.24953/turkjped.2021.5050.

ABSTRACT

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) rates have increased in cystic fibrosis (CF) patients.This study aimed to determine the rate of MRSA, define risk factors, and clarify the effect of MRSA on pulmonary functions, annual pulmonary exacerbation (aPEx) in children with MRSA positive CF.

METHODS: This was a retrospective case control study. CF patients who had ≥1 MRSA (+) respiratory culture between September 2016-2019 were included. MRSA growth rate, colonization status, clinical characteristics, hospitalization rates, FEV1 %predicted, and z-score one year prior to the MRSA isolation, at MRSA growth and one year after MRSA growth were recorded. The aPEx rate changes before-after MRSA growth were evaluated.

RESULTS: Sixty-one subjects who had ≥1MRSA growth and 66 controls were enrolled. There was no statistically significant difference between the spirometry indices at first, and 12th month after MRSA acquisition. The mean aPEx was 0.6 one year prior to MRSA acquisition and this rate significantly increased to 1.2 one year after MRSA growth(p < 0.05). The mean hospitalization rate before and after one year of MRSA acquisition significantly increased from 0.17(±0.12) to 0.48 (±0.3)(p:0.008) admissions per year.

CONCLUSIONS: MRSA growth was related to increased aPEx. Increased aPEx and hospitalization rates after MRSA acquisition suggest MRSA should be eradicated when detected.

PMID:36305434 | DOI:10.24953/turkjped.2021.5050

Front Pharmacol. 2022 Oct 11;13:1015926. doi: 10.3389/fphar.2022.1015926. eCollection 2022.

ABSTRACT

Cystic fibrosis (CF) is a life-threatening autosomal-recessive disease caused by mutations in a single gene encoding cystic fibrosis transmembrane conductance regulator (CFTR). CF effects multiple organs, and lung disease is the primary cause of mortality. The median age at death from CF is in the early forties. CF was one of the first diseases to be considered for gene therapy, and efforts focused on treating CF lung disease began shortly after the CFTR gene was identified in 1989. However, despite the quickly established proof-of-concept for CFTR gene transfer in vitro and in clinical trials in 1990s, to date, 36 CF gene therapy clinical trials involving ∼600 patients with CF have yet to achieve their desired outcomes. The long journey to pursue gene therapy as a cure for CF encountered more difficulties than originally anticipated, but immense progress has been made in the past decade in the developments of next generation airway transduction viral vectors and CF animal models that reproduced human CF disease phenotypes. In this review, we look back at the history for the lessons learned from previous clinical trials and summarize the recent advances in the research for CF gene therapy, including the emerging CRISPR-based gene editing strategies. We also discuss the airway transduction vectors, large animal CF models, the complexity of CF pathogenesis and heterogeneity of CFTR expression in airway epithelium, which are the major challenges to the implementation of a successful CF gene therapy, and highlight the future opportunities and prospects.

PMID:36304167 | PMC:PMC9592762 | DOI:10.3389/fphar.2022.1015926

Pharmaceuticals (Basel). 2022 Oct 18;15(10):1281. doi: 10.3390/ph15101281.

ABSTRACT

Pediatric patients receiving respiratory support with heated flow nasal cannula (HFNC) systems frequently receive inhaled medications. Most available data have been obtained with vibrating mesh nebulizers that are expensive. Data are lacking regarding the feasibility of using less expensive devices such as continuous output jet nebulizers. The characteristics of the aerosols generated by jet nebulizers operated at different conditions (6 and 9 L/min) were studied alone and connected to a HFNC system and different size cannulas using a cascade impactor and spectrophotometry (276 nm). Aerosol characteristics changed while traveling through the HFNC system. Initial size selection occurred at the exit of the circuit (before connecting to the cannula) with all aerosol &lt;5 µm. Nasal cannula size further selected aerosols and reduced drug delivery. The operating flow of the nebulizer did not affect the delivered mass but higher flows generated smaller particle size aerosols. The addition of supplemental flow significantly reduced the delivered mass. The measured aerosol characteristics would likely result in intrapulmonary deposition. The delivery of aerosolized albuterol generated by a continuous output nebulizer placed in the inlet of a HFNC system and connected to large or XXL cannulas is feasible.

PMID:36297393 | PMC:PMC9607327 | DOI:10.3390/ph15101281

ACS Biomater Sci Eng. 2022 Oct 27. doi: 10.1021/acsbiomaterials.2c00777. Online ahead of print.

ABSTRACT

Deoxyribonucleic acid (DNA) evolved as a tool for storing and transmitting genetic information within cells, but outside the cell, DNA can also serve as "construction material" present in microbial biofilms or various body fluids, such as cystic fibrosis, sputum, and pus. In the present work, we investigate the mechanics of biofilms formed from Pseudomonas aeruginosa Xen 5, Staphylococcus aureus Xen 30, and Candida albicans 1408 using oscillatory shear rheometry at different levels of compression and recreate these mechanics in systems of entangled DNA and cells. The results show that the compression-stiffening and shear-softening effects observed in biofilms can be reproduced in DNA networks with the addition of an appropriate number of microbial cells. Additionally, we observe that these effects are cell-type dependent. We also identify other mechanisms that may significantly impact the viscoelastic behavior of biofilms, such as the compression-stiffening effect of DNA cross-linking by bivalent cations (Mg2+, Ca2+, and Cu2+) and the stiffness-increasing interactions of P. aeruginosa Xen 5 biofilm with Pf1 bacteriophage produced by P. aeruginosa. This work extends the knowledge of biofilm mechanobiology and demonstrates the possibility of modifying biopolymers toward obtaining the desired biophysical properties.

PMID:36301743 | DOI:10.1021/acsbiomaterials.2c00777

J Med Microbiol. 2022 Oct;71(10). doi: 10.1099/jmm.0.001593.

ABSTRACT

Background. Antimicrobial resistance (AMR) is an ever-increasing global health concern. One crucial facet in tackling the AMR epidemic is earlier and more accurate AMR diagnosis, particularly in the dangerous and highly multi-drug-resistant ESKAPE pathogen, Pseudomonas aeruginosa.Objectives. We aimed to develop two SYBR Green-based mismatch amplification mutation assays (SYBR-MAMAs) targeting GyrA T83I (gyrA248) and GyrA D87N, D87Y and D87H (gyrA259). Together, these variants cause the majority of fluoroquinolone (FQ) AMR in P. aeruginosa.Methods. Following assay validation, the gyrA248 and gyrA259 SYBR-MAMAs were tested on 84 Australian clinical P. aeruginosa isolates, 46 of which demonstrated intermediate/full ciprofloxacin resistance according to antimicrobial susceptibility testing.Results. Our two SYBR-MAMAs correctly predicted an AMR phenotype in the majority (83%) of isolates with intermediate/full FQ resistance. All FQ-sensitive strains were predicted to have a sensitive phenotype. Whole-genome sequencing confirmed 100 % concordance with SYBR-MAMA genotypes.Conclusions. Our GyrA SYBR-MAMAs provide a rapid and cost-effective method for same-day identification of FQ AMR in P. aeruginosa. An additional SYBR-MAMA targeting the GyrB S466Y/S466F variants would increase FQ AMR prediction to 91 %. Clinical implementation of our assays will permit more timely treatment alterations in cases where decreased FQ susceptibility is identified, leading to improved patient outcomes and antimicrobial stewardship.

PMID:36301593 | DOI:10.1099/jmm.0.001593

Acta Biomed. 2022 Oct 26;93(5):e2022295. doi: 10.23750/abm.v93i5.12896.

ABSTRACT

Background Cystic fibrosis related diabetes is a complication of cystic fibrosis (CF). Aim of our study was to evaluate the effects of insulin therapy in overt diabetics or pre-diabetics CF patients on BMI and respiratory function. Methods We selected a sample of 17 insulin treated patients (Group T) and a sample of 17 CF control patients with normal glucose metabolism (Group C). Group T was also subdivided into overt diabetic patients and pre-diabetic patients (IGT, INDET). For treated patients an observation period was established from the first insulin administration to 12 months. For control patients, a comparable year of observation was chosen. Data regarding BMI, FVC, FEV1 and PEF were collected at time 0, and at time 12. The number of hospital admissions for infectious episodes during the year of observation and during the preceding year were recorded for Group T patients. Results The results showed a significant increase in BMI in treated patients compared to control, specially for overt diabetics. The study of spirometric parameters showed a significant improvement of PEF, the main effort-dependent respiratory index, specially for over diabetics, suggesting a hypothetical positive impact of the insulin anabolic action on the magnitude of expiratory effort. In contrast, the study of infectious episodes revealed a significant reduction of hospital admissions in pre diabetic treated patients. Conclusion Overall, our study focuses on the importance of glycemic monitoring during the early stages of CF disease and on the advantage of insulin treatment in the early stages of glucose alteration .

PMID:36300234 | DOI:10.23750/abm.v93i5.12896