Pancreatic Cancer-Associated Diabetes is Clinically Distinguishable From Conventional Diabetes.

J Surg Res. 2021 Jan 13;261:215-225

Authors: Yoon BH, Ang SM, Alabd A, Furlong K, Yeo CJ, Lavu H, Winter JM

Abstract
BACKGROUND: Type 3c diabetes mellitus (T3cDM) is diabetes secondary to other pancreatic diseases such as chronic pancreatitis, pancreatic resection, cystic fibrosis, and pancreatic ductal adenocarcinoma (PDA). Clinically, it may easily be confused with conventional type 2 diabetes mellitus (T2DM). A delay in pancreatic cancer diagnosis and treatment leads to a worse outcome. Therefore, early recognition of PDA-associated T3cDM and distinction from conventional T2DM represents an opportunity improve survival in patients with PDA.
METHODS: Six hundred and sixty four patients with PDA underwent pancreatic resection. Patients were classified as per whether or not they had diabetes. The specific type of diabetes was determined. T3cDM surgical patients (n = 127) were compared with a control group of medical patients with T2DM who did not have PDA (n = 127).
RESULTS: Patients with T3cDM were older (66 versus 61 y, P < 0.001), had lower body mass indices (25.9 versus 32.1, P < 0.001), more favorable hemoglobin A1c levels (7.0 versus 8.8, P < 0.001), higher alanine aminotransferase levels (39 versus 20, P < 0.001), and lower creatinine levels (0.8 versus 0.9 mg/dL, P < 0.001). In addition, they were more likely to be insulin dependent. In a subgroup analysis of surgical patients, T3cDM (versus surgical patients with T2DM and no diabetes) was not associated with surrogate markers of main pancreatic duct obstruction and glandular atrophy.
CONCLUSIONS: PDA-associated T3cDM has a distinctive presenting phenotype compared with medical patients with conventional T2DM. Greater attention to associated signs, symptoms, and biochemical data could identify patients at risk for harboring an underlying pancreatic malignancy and trigger diagnostic pathways leading to earlier PDA diagnosis and treatment.

PMID: 33453685 [PubMed - as supplied by publisher]

Commentary for the article: MicroRNA-1246 regulates proliferation, invasion and differentiation in human vascular smooth muscle cell by targeting cystic fibrosis transmembrane conductance regulator (CFTR).

Pflugers Arch. 2021 Jan 16;:

Authors: Choi MR

PMID: 33452915 [PubMed - as supplied by publisher]

Phenotype and Natural History of Children With Coexistent Inflammatory Bowel Disease and Celiac Disease.

Inflamm Bowel Dis. 2021 Jan 16;:

Authors: Bramuzzo M, Lionetti P, Miele E, Romano C, Arrigo S, Cardile S, Di Nardo G, Illiceto MT, Pastore M, Felici E, Fuoti M, Banzato C, Citrano M, Congia M, Norsa L, Pozzi E, Zuin G, Agrusti A, Bianconi M, Grieco C, Giudici F, Aloi M, Alvisi P

Abstract
BACKGROUND: Adult patients with both inflammatory bowel disease (IBD) and celiac disease (CeD) have peculiar phenotypic features. This study aimed at describing the characteristics and natural history of children with both IBD and CeD.
METHODS: This was a case-control study based on a national registry. Cases included children diagnosed with both IBD and CeD. Two matched IBD controls without CeD, and 2 matched CeD controls were selected for each case. Inflammatory bowel disease phenotype and natural history, comprising growth and pubertal development, were compared between groups.
RESULTS: Forty-nine (1.75%) patients with IBD and CeD were identified out of 2800 patients with IBD. Compared with patients with IBD alone, patients with IBD and CeD presented more frequently with autoimmune diseases (odds ratio, 2.81; 95% CI, 0.97-8.37; P = 0.04). Ileocolonic localization (46.1% vs 73.1%), treatment with azathioprine (46.2% vs 71.2%), and anti-TNF biologics (46.2% vs 69.2%) were less common in patients with Crohn's disease and CeD than in patients with Crohn's disease alone. Patients with ulcerative colitis and CeD had an increased risk of colectomy despite similar medical treatments compared with patients with ulcerative colitis alone (13.0% vs 0%). Pubertal delay was more common in patients with IBD and CeD compared with patients with IBD alone (14.9% vs 3.2%; odds artio, 5.24; 95% CI, 1.13-33.0; P = 0.02) and CeD alone (14.9% vs 1.1%; P = 0.002).
CONCLUSIONS: Children with IBD and CeD may have peculiar features with a higher risk for autoimmune diseases, colectomy, and pubertal delay compared with IBD alone.

PMID: 33452803 [PubMed - as supplied by publisher]

Diagnosis of cystic fibrosis in adulthood and eligibility for novel CFTR modulator therapy.

Postgrad Med J. 2021 Jan 15;:

Authors: Farley H, Poole S, Chapman S, Flight W

Abstract
BACKGROUND: Cystic fibrosis (CF) is an autosomal recessive condition that primarily manifests as a chronic respiratory disease. CF is usually diagnosed in early childhood or through newborn screening although in a small but important group, diagnosis is not made until adulthood. Highly effective cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapies are now available for most genetic causes of CF highlighting the importance of identifying people with late presentations of CF.
AIM: We aimed to identify the clinical characteristics of people diagnosed with CF in adulthood and their resulting eligibility for novel CFTR modulator therapies.
DESIGN: Retrospective single-centre cohort study.
METHODS: Patients diagnosed with CF at age 18 years or older were identified from a patient database. Paper and electronic medical records were reviewed and clinical, microbiological and radiological data at diagnosis were recorded.
RESULTS: Nineteen patients were identified. Median age at diagnosis was 38 years (range: 19-71) and 9 (47%) were female. All patients had a history of chronic respiratory symptoms and 18/19 (94%) had radiological evidence of bronchiectasis. All patients had two pathogenic CFTR mutations identified with 16/19 (84%) compound heterozygotes for the F508del mutation. The majority of patients had a CFTR genotype considered eligible for CFTR modulator therapy (84% and 89% according to European and US licences, respectively).
CONCLUSIONS: Adult patients with unexplained chronic bronchiectasis should be thoroughly investigated for CF. A low index of suspicion will help to identify adults with undiagnosed CF who are likely to benefit from CFTR modulator therapy.

PMID: 33452147 [PubMed - as supplied by publisher]

Signal Synthase-Type versus Catabolic Monooxygenases: Retracing 3-Hydroxylation of 2-Alkylquinolones and Their N-Oxides by Pseudomonas aeruginosa and Other Pulmonary Pathogens.

Appl Environ Microbiol. 2021 Jan 15;:

Authors: Ritzmann NH, Drees SL, Fetzner S

Abstract
The multiple biological activities of 2-alkylquinolones (AQs) are crucial for virulence of Pseudomonas aeruginosa, conferring advantages during infection and in polymicrobial communities. Whereas 2-heptyl-3-hydroxyquinolin-4(1H)-one (the "Pseudomonas quinolone signal", PQS) is an important quorum sensing signal molecule, 2-heptyl-1-hydroxyquinolin-4(1H)-ones (also known as 2-alkyl-4-hydroxyquinoline-N-oxides, AQNOs) are antibiotics inhibiting respiration. Hydroxylation of the PQS precursor 2-heptylquinolin-4(1H)-one (HHQ) by the signal synthase PqsH boosts AQ quorum sensing. Remarkably, the same reaction, catalyzed by the ortholog AqdB, is used by Mycobacteroides abscessus to initiate degradation of AQs. The antibiotic 2-heptyl-1-hydroxyquinolin-4(1H)-one (HQNO) is hydroxylated by Staphylococcus aureus to the less toxic derivative PQS-N-oxide (PQS-NO), a reaction probably also catalyzed by a PqsH/AqdB ortholog. In this study, we provide a comparative analysis of four AQ 3-monooxygenases of different organisms. Due to the major impact of AQ/AQNO 3-hydroxylation on the biological activities of the compounds, we surmised adaptations on enzymatic and/or physiological level to serve either the producer or target organisms. Our results indicate that all enzymes share similar features and are incapable of discriminating between AQs and AQNOs. PQS-NO hence occurs as native metabolite of P. aeruginosa although the unfavorable AQNO 3-hydroxylation is minimized by export as shown for HQNO, involving at least one multidrug efflux pump. Moreover, M. abscessus is capable of degrading the AQNO heterocycle by concerted action of AqdB and dioxygenase AqdC. However, S. aureus and M. abscessus orthologs disfavor AQNOs despite their higher toxicity, suggesting that catalytic constraints, rather than evolutionary adaptation, lead to the preference of non-N-oxide substrates by AQ 3-monooxygenases.IMPORTANCE Pseudomonas aeruginosa, Staphylococcus aureus and Mycobacteroides abscessus are major players in bacterial chronic infections and particularly common colonizers of cystic fibrosis (CF) lung tissue. Whereas S. aureus is an early onset pathogen in CF, P. aeruginosa establishes at later stages. M. abscessus occurs at all stages but has a lower epidemiological incidence. The dynamics of how these pathogens interact can affect survival and therapeutic success.2-Alkylquinolone (AQ) and 2-alkylhydroxyquinoline N-oxide (AQNO) production is a major factor of P. aeruginosa virulence. The 3-position of the AQ scaffold is critical, both for attenuation of AQ toxicity or degradation by competitors, as well as for full unfolding of quorum sensing. Despite lacking signaling functionality, AQNOs have the strongest impact on suppression of Gram-positives. Because evidence for 3-hydroxylation of AQNOs has been reported, it is desirable to understand the extent by which AQ 3-monooxygenases contribute to manipulation of the AQ/AQNO equilibrium, resistance, and degradation.

PMID: 33452035 [PubMed - as supplied by publisher]

Designing the GALAXY study: Partnering with the cystic fibrosis community to optimize assessment of gastrointestinal symptoms.

J Cyst Fibros. 2021 Jan 12;:

Authors: Freeman AJ, Sathe M, Aliaj E, Borowitz D, Fogarty B, Goss CH, Freedman S, Heltshe SL, Khan U, Riva D, Roman C, Romasco M, Schwarzenberg SJ, Ufret-Vincenty CA, Moshiree B

Abstract
BACKGROUND: Gastrointestinal (GI) involvement among persons with cystic fibrosis (CF) is highly prevalent, representing a significant source of morbidity. Persons with CF have identified GI concerns as a top research priority, yet universal clinical outcome measures capturing many of the GI symptoms experienced in CF are lacking. The GALAXY study was envisioned to address this unmet need.
METHODS: The GALAXY study team partnered with Community Voice, a community of patients with CF and their caregivers, to identify the patient reported outcome measures that most accurately reflected their experience with GI symptoms in CF. We also surveyed CF care teams to identify the comfort level of various team members (providers, nurses and dieticians) in managing a variety of GI conditions.
RESULTS: Members of Community Voice identified the combination of PAC-SYM, PAGI-SYM, PAC-QOL and the Bristol Stool scale with three additional symptom-specific questions as patient-reported outcome measures that comprehensively captured the CF experience with GI disease. CF care team providers reported a high level of comfort in treating GI conditions including constipation (92%), GERD (93%), and gassiness (77%), however comfort level was limited to only first-line interventions.
CONCLUSION: By partnering with persons with CF as well as their caregivers and medical providers, the GALAXY study is designed to uniquely capture the prevalence and severity of GI involvement among persons with CF in a manner that reflects the CF patient experience. The results of GALAXY will inform the development of future interventional trials and serve as a reproducible and objective study endpoint.

PMID: 33451899 [PubMed - as supplied by publisher]

The Aspergillus fumigatus Secretome Alters the Proteome of Pseudomonas aeruginosa to Stimulate Bacterial Growth: Implications for Co-infection.

Mol Cell Proteomics. 2020 Aug;19(8):1346-1359

Authors: Margalit A, Carolan JC, Sheehan D, Kavanagh K

Abstract
Individuals with cystic fibrosis are susceptible to co-infection by Aspergillus fumigatus and Pseudomonas aeruginosa. Despite the persistence of A. fumigatus in the cystic fibrosis lung P. aeruginosa eventually predominates as the primary pathogen. Several factors are likely to facilitate P. aeruginosa colonization in the airways, including alterations to the microbial environment. The cystic fibrosis airways are hypoxic, nitrate-rich environments, and the sputum has higher amino acid concentrations than normal. In this study, significant growth proliferation was observed in P. aeruginosa when the bacteria were exposed to A. fumigatus culture filtrates (CuF) containing a high nitrate content. Proteomic analysis of the A. fumigatus CuF identified a significant number of environment-altering proteases and peptidases. The molecular mechanisms promoting bacterial growth were investigated using label-free quantitative (LFQ) proteomics to compare the proteome of P. aeruginosa grown in the A. fumigatus CuF and in CuF produced by a P. aeruginosa-A. fumigatus co-culture, to that cultured in P. aeruginosa CuF. LFQ proteomics revealed distinct changes in the proteome of P. aeruginosa when cultured in the different CuFs, including increases in the levels of proteins involved in denitrification, stress response, replication, amino acid metabolism and efflux pumps, and a down-regulation of pathways involving ABC transporters. These findings offer novel insights into the complex dynamics that exist between P. aeruginosa and A. fumigatus. Understanding the molecular strategies that enable P. aeruginosa to predominate in an environment where A. fumigatus exists is important in the context of therapeutic development to target this pathogen.

PMID: 33451508 [PubMed - as supplied by publisher]

Pannexin 1 Channels Control the Hemodynamic Response to Hypoxia by Regulating O2-Sensitive Extracellular ATP in Blood.

Am J Physiol Heart Circ Physiol. 2021 Jan 15;:

Authors: Kirby BS, Sparks MA, Lazarowski ER, Lopez Domowicz DA, Zhu H, McMahon TJ

Abstract
Pannexin1 (Panx1) channels export ATP and may contribute to increased concentration of the vasodilator ATP in plasma during hypoxia in vivo. We hypothesized that Panx1 channels and associated ATP export contributes to hypoxic vasodilation, a mechanism that facilitates the matching of oxygen delivery to tissue metabolic demand. Male and female mice devoid of Panx1 (Panx1-/-) and wild-type controls (WT) were anesthetized, mechanically ventilated, and instrumented with a carotid artery catheter or femoral artery flow transducer for hemodynamic and plasma ATP monitoring during inhalation of 21% (normoxia) or 10% oxygen (hypoxia). ATP export from WT vs. Panx1-/- erythrocytes (RBC) was determined ex vivo via tonometer experimentation across progressive deoxygenation. Mean arterial pressure (MAP) was similar in Panx1-/- (N=6) and WT (N=6) mice in normoxia, but the decrease in MAP in hypoxia seen in WT was attenuated in Panx1-/- mice (-16±9% vs -2±8%; P<0.05). Hindlimb blood flow (HBF) was significantly lower in Panx1-/- (N=6) vs. WT (N=6) basally, and increased in WT but not Panx1-/- mice during hypoxia (8±6% vs -10±13%; P<0.05). Estimation of hindlimb vascular conductance using data from the MAP and HBF experiments showed an average response of 28% for WT vs -9% for Panx1-/- mice. Mean venous plasma ATP during hypoxia was 57% lower in Panx1-/- (N=6) vs WT mice (N=6) (P<0.05). Mean hypoxia-induced ATP export from RBCs from Panx1-/- mice (N=8) was 82% lower than from WT (N=8) ( P<0.05). Panx1 channels participate in hemodynamic responses consistent with hypoxic vasodilation by regulating hypoxia-sensitive extracellular ATP levels in blood.

PMID: 33449849 [PubMed - as supplied by publisher]

An interbacterial DNA deaminase toxin directly mutagenizes surviving target populations.

Elife. 2021 Jan 15;10:

Authors: de Moraes MH, Hsu F, Huang D, Bosch DE, Zeng J, Radey MC, Simon N, Ledvina HE, Frick JP, Wiggins PA, Peterson SB, Mougous JD

Abstract
When bacterial cells come in contact, antagonism mediated by the delivery of toxins frequently ensues. The potential for such encounters to have long-term beneficial consequences in recipient cells has not been investigated. Here we examined the effects of intoxication by DddA, a cytosine deaminase delivered via the type VI secretion system (T6SS) of Burkholderia cenocepacia. Despite its killing potential, we observed that several bacterial species resist DddA and instead accumulate mutations. These mutations can lead to the acquisition of antibiotic resistance, indicating that even in the absence of killing, interbacterial antagonism can have profound consequences on target populations. Investigation of additional toxins from the deaminase superfamily revealed that mutagenic activity is a common feature of these proteins, including a representative we show targets single-stranded DNA and displays a markedly divergent structure. Our findings suggest that a surprising consequence of antagonistic interactions between bacteria could be the promotion of adaptation via the action of directly mutagenic toxins.

PMID: 33448264 [PubMed - as supplied by publisher]

Antibiotics in Adult Cystic Fibrosis Patients: A Review of Population Pharmacokinetic Analyses.

Clin Pharmacokinet. 2021 Jan 15;:

Authors: El Hassani M, Caissy JA, Marsot A

Abstract
BACKGROUND: Lower respiratory tract infections are common in adult patients with cystic fibrosis (CF) and are frequently caused by Pseudomonas aeruginosa, resulting in chronic lung inflammation and fibrosis. The progression of multidrug-resistant strains of P. aeruginosa and alterations in the pharmacokinetics of many antibiotics in CF make optimal antimicrobial therapy a challenge, as reflected by high between- and inter-individual variability (IIV).
OBJECTIVES: This review provides a synthesis of population pharmacokinetic models for various antibiotics prescribed in adult CF patients, and aims at identifying the most reported structural models, covariates and sources of variability influencing the dose-concentration relationship.
METHODS: A literature search was conducted using the PubMed database, from inception to August 2020, and articles were retained if they met the inclusion/exclusion criteria.
RESULTS: A total of 19 articles were included in this review. One-, two- and three-compartment models were reported to best describe the pharmacokinetics of various antibiotics. The most common covariates were lean body mass and creatinine clearance. After covariate inclusion, the IIV (range) in total body clearance was 27.2% (10.40-59.7%) and 25.9% (18.0-33.9%) for β-lactams and aminoglycosides, respectively. IIV in total body clearance was estimated at 36.3% for linezolid and 22.4% for telavancin. The IIV (range) in volume of distribution was 29.4% (8.8-45.9%) and 15.2 (11.6-18.0%) for β-lactams and aminoglycosides, respectively, and 26.9% for telavancin. The median (range) of residual variability for all studies, using a combined (proportional and additive) model, was 12.7% (0.384-30.80%) and 0.126 mg/L (0.007-1.88 mg/L), respectively.
CONCLUSION: This is the first review that highlights key aspects of different population pharmacokinetic models of antibiotics prescribed in adult CF patients, effectively proposing relevant information for clinicians and researchers to optimize antibiotic therapy in CF.

PMID: 33447944 [PubMed - as supplied by publisher]

Antibiotic susceptibility of cystic fibrosis lung microbiome members in a multispecies biofilm.

Biofilm. 2020 Dec;2:100031

Authors: Vandeplassche E, Sass A, Ostyn L, Burmølle M, Kragh KN, Bjarnsholt T, Coenye T, Crabbé A

Abstract
The lungs of cystic fibrosis (CF) patients are often chronically colonized by multiple microbial species that can form biofilms, including the major CF pathogen Pseudomonas aeruginosa. Herewith, lower microbial diversity in CF airways is typically associated with worse health outcomes. In an attempt to treat CF lung infections patients are frequently exposed to antibiotics, which may affect microbial diversity. This study aimed at understanding if common antibiotics that target P. aeruginosa influence microbial diversity. To this end, a microaerophilic multispecies biofilm model of frequently co-isolated members of the CF lung microbiome (Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus anginosus, Achromobacter xylosoxidans, Rothia mucilaginosa, and Gemella haemolysans) was exposed to antipseudomonal antibiotics. We found that antibiotics that affected several dominant species (i.e. ceftazidime, tobramycin) resulted in higher species evenness compared to colistin, which is only active against P. aeruginosa. Furthermore, susceptibility of individual species in the multispecies biofilm following antibiotic treatment was compared to that of the respective single-species biofilms, showing no differences. Adding three anaerobic species (Prevotella melaninogenica, Veillonella parvula, and Fusobacterium nucleatum) to the multispecies biofilm did not influence antibiotic susceptibility. In conclusion, our study demonstrates antibiotic-dependent effects on microbial community diversity of multispecies biofilms comprised of CF microbiome members.

PMID: 33447816 [PubMed]

Weak acids as an alternative anti-microbial therapy.

Biofilm. 2020 Dec;2:100019

Authors: Kundukad B, Udayakumar G, Grela E, Kaur D, Rice SA, Kjelleberg S, Doyle PS

Abstract
Weak acids such as acetic acid and N-acetyl cysteine (NAC) at pH less than their pKa can effectively eradicate biofilms due to their ability to penetrate the biofilm matrix and the cell membrane. However, the optimum conditions for their activity against drug resistant strains, and safety, need to be understood for their application to treat infections or to inactivate biofilms on hard surfaces. Here, we investigate the efficacy and optimum conditions at which weak acids can eradicate biofilms. We compared the efficacy of various mono and triprotic weak acids such as N-acetyl cysteine (NAC), acetic acid, formic acid and citric acid, in eradicating biofilms. We found that monoprotic weak acids/acid drugs can kill mucoid P. aeruginosa mucA biofilm bacteria provided the pH is less than their pKa, demonstrating that the extracellular biofilm matrix does not protect the bacteria from the activity of the weak acids. Triprotic acids, such as citric acid, kill biofilm bacteria at pH ​< ​pKa1. However, at a pH between pKa1 and pKa2, citric acid is effective in killing the bacteria at the core of biofilm microcolonies but does not kill the bacteria on the periphery. The efficacy of a monoprotic weak acid (NAC) and triprotic weak acid (citric acid) were tested on biofilms formed by Klebsiella pneumoniae KP1, Pseudomonas putida OUS82, Staphylococcus aureus 15981, P. aeruginosa DK1-NH57388A, a mucoid cystic fibrosis isolate and P. aeruginosa PA_D25, an antibiotic resistant strain. We showed that weak acids have a broad spectrum of activity against a wide range of bacteria, including antibiotic resistant bacteria. Further, we showed that a weak acid drug, NAC, can kill bacteria without being toxic to human cells, if its pH is maintained close to its pKa. Thus weak acids/weak acid drugs target antibiotic resistant bacteria and eradicate the persister cells in biofilms which are tolerant to other conventional methods of biofilm eradication.

PMID: 33447805 [PubMed]

[Bird fancier's disease in a child: about a rare and unusual case].

Pan Afr Med J. 2020;37:189

Authors: Jallouli A, Fakiri KE, Rada N, Draiss G, Bouskraoui M

Abstract
Bird fancier's disease falls within the spectrum of hypersensitivity pneumonitis secondary to immuno-allergic reaction to avian antigens. This occurs only rarely in children. It is found in two-thirds of patients with hypersensitivity pneumonitis. Diagnosis is not so easy. It is based on a body of clinical evidence. We here report the peculiar case of a 7-year-old girl with a family history of atopic disease initially treated as asthma based on the presence of wheezing and dyspnea and cough without improvement. The patient had worsening of symptoms such as dyspnea at rest complicated by cyanosis in respiratory distress. All of this took place in a context of alteration of general state. Clinical examination showed growth retardation, perioral cyanosis with digital hippocratism. Lung auscultation revealed bilateral crackling sounds. Chest X-ray objectified bilateral interstitial syndrome. Chest computed tomography (CT) scan showed diffuse ground-glass opacities. Laboratory tests revealed hypereosinophilia with hyper-IgE and excluded tuberculosis, cystic fibrosis, immune deficiency. In a second stage interview contact with birds was reported. Serological tests for bird fancier's disease were positive. The patient received inhaled corticosteroids associated with avoidance of exposure to birds. After a follow-up of 2 months, outcome was favorable. Given that the signs of bird fancier's disease are non-specific, this should be suspected in patients with respiratory symptoms associated with exposure to avian antigens.

PMID: 33447344 [PubMed - in process]

Unsupervised Phenotypic Clustering for Determining Clinical Status in Children with Cystic Fibrosis.

Eur Respir J. 2021 Jan 14;:

Authors: Filipow N, Davies G, Main E, Sebire NJ, Wallis C, Ratjen F, Stanojevic S

Abstract
BACKGROUND: Cystic Fibrosis (CF) is a multisystem disease in which assessing disease severity based on lung function alone may not be appropriate. The aim of the study was to develop a comprehensive machine-learning algorithm to assess clinical status independent of lung function in children.
METHODS: A comprehensive prospectively collected clinical database (Toronto, Canada) was used to apply unsupervised cluster analysis. The defined clusters were then compared by current and future lung function, risk of future hospitalisation, and risk of future pulmonary exacerbation (PEx) treated with oral antibiotics. A K-Nearest Neighbours (KNN) algorithm was used to prospectively assign clusters. The methods were validated in a paediatric clinical CF dataset from Great Ormond Street Hospital (GOSH).
RESULTS: The optimal cluster model identified four (A-D) phenotypic clusters based on 12 200 encounters from 530 individuals. Two clusters (A,B) consistent with mild disease were identified with high FEV1, and low risk of both hospitalisation and PEx treated with oral antibiotics. Two clusters (C,D) consistent with severe disease were also identified with low FEV1. Cluster D had the shortest time to both hospitalisation and PEx treated with oral antibiotics. The outcomes were consistent in 3124 encounters from 171 children at GOSH. The KNN cluster allocation error rate was low, at 2.5% (Toronto), and 3.5% (GOSH).
CONCLUSION: Machine learning derived phenotypic clusters can predict disease severity independent of lung function and could be used in conjunction with functional measures to predict future disease trajectories in CF patients.

PMID: 33446607 [PubMed - as supplied by publisher]

Complete Genome Sequence of Achromobacter xylosoxidans Myophage Mano.

Microbiol Resour Announc. 2021 Jan 14;10(2):

Authors: Bartz M, Yao G, Le T, Liu M, Burrowes B, Gonzalez C, Young R

Abstract
Achromobacter spp. are ubiquitous Gram-negative bacteria, some of which can cause respiratory tract infections in patients with autoimmune disorders and cystic fibrosis. Bacteriophages have therapeutic and biotechnological potential to combat Achromobacter sp. infections. This announcement details the 42.5-kb genome sequence of the temperate Achromobacter xylosoxidans myophage Mano.

PMID: 33446599 [PubMed]

Towards human translation of lentiviral airway gene delivery for cystic fibrosis: A one-month CFTR and reporter gene study in marmosets.

Hum Gene Ther. 2021 Jan 15;:

Authors: Farrow NR, Cmielewski P, Delhove J, Rout-Pitt N, Vaughan L, Kuchel T, Christou C, Finnie J, Smith M, Knight E, Donnelley M, Parsons D

Abstract
Gene therapy continues to be a promising contender for the treatment of cystic fibrosis (CF) airway disease. We have previously demonstrated that airway conditioning with lysophosphatidylcholine (LPC) followed by delivery of a HIV-1 based lentiviral vector (LV) functionally corrects the CF transmembrane conductance regulator (CFTR) defect in the nasal airways of CF mice. In our earlier pilot study we showed that our technique can transduce marmoset lungs acutely; this study extends that work to examine gene expression in this non-human primate (NHP) 1 month after gene vector treatment. A mixture of three separate HIV-1 VSV-G pseudotyped LV vectors containing the luciferase (Luc), LacZ and hCFTR transgenes was delivered into the trachea via a miniature bronchoscope. We examined whether a single-dose delivery of lentiviral vector after LPC conditioning could increase levels of transgene expression in the trachea and lungs compared to control (PBS) conditioning. At one month, bioluminescence was detected in vivo in the trachea of 3 of the 6 animals within the PBS control group, compared to 5 of the 6 LPC-treated animals. When examined ex vivo there was weak evidence that LPC improves tracheal Luc expression levels. In the lungs, bioluminescence was detected in vivo in 4 of the 6 PBS treated animals, compared to 5 of the 6 LPC treated animals; however, bioluminescence was present in all lungs when imaged ex vivo. LacZ expression was predominantly observed in the alveolar regions of the lung. hCFTR was detected by qPCR in the lungs of 5 of the 11 animals. Basal cells were successfully isolated and expanded from marmoset tracheas, but no LacZ positive colonies were detected. There was no evidence of an inflammatory response towards the LV vector at one month post-delivery, with cytokines remaining at baseline levels. In conclusion, we found weak evidence that LPC conditioning improved gene transduction in the trachea, but not in the marmoset lungs. We also highlight some of the challenges associated with translational lung gene therapy studies in NHPs.

PMID: 33446042 [PubMed - as supplied by publisher]

Early Phases of COVID-19 Are Characterized by a Reduction in Lymphocyte Populations and the Presence of Atypical Monocytes.

Front Immunol. 2020;11:560330

Authors: Lombardi A, Trombetta E, Cattaneo A, Castelli V, Palomba E, Tirone M, Mangioni D, Lamorte G, Manunta M, Prati D, Ceriotti F, Gualtierotti R, Costantino G, Aliberti S, Scaravilli V, Grasselli G, Gori A, Porretti L, Bandera A

Abstract
Background: Severe acute respiratory syndrome coronavirus 2 is a recently discovered pathogen responsible of coronavirus disease 2019 (COVID-19). The immunological changes associated with this infection are largely unknown.
Methods: We evaluated the peripheral blood mononuclear cells profile of 63 patients with COVID-19 at diagnosis. We also assessed the presence of association with inflammatory biomarkers and the 28-day mortality.
Results: Lymphocytopenia was present in 51 of 63 (80.9%) patients, with a median value of 720 lymphocytes/µl (IQR 520-1,135). This reduction was mirrored also on CD8+ (128 cells/µl, IQR 55-215), natural killer (67 cells/µl, IQR 35-158) and natural killer T (31 cells/µl, IQR 11-78) cells. Monocytes were preserved in total number but displayed among them a subpopulation with a higher forward and side scatter properties, composed mainly of cells with a reduced expression of both CD14 and HLA-DR. Patients who died in the 28 days from admission (N=10, 15.9%), when compared to those who did not, displayed lower mean values of CD3+ (337.4 cells/µl vs 585.9 cells/µl; p=0.028) and CD4+ cells (232.2 cells/µl vs 381.1 cells/µl; p=0.042) and an higher percentage of CD8+/CD38+/HLA-DR+ lymphocytes (13.5% vs 7.6%; p=0.026).
Discussion: The early phases of COVID-19 are characterized by lymphocytopenia, predominance of Th2-like lymphocytes and monocytes with altered immune profile, which include atypical mononuclear cells.

PMID: 33362757 [PubMed - indexed for MEDLINE]

Assessing the applicability of the new Global Lung Function Initiative reference values for the diffusing capacity of the lung for carbon monoxide in a large population set.

PLoS One. 2021;16(1):e0245434

Authors: Wardyn PM, de Broucker V, Chenivesse C, Sobaszek A, Van Bulck R, Perez T, Edmé JL, Hulo S

Abstract
BACKGROUND: The single-breath diffusing capacity of the lung for carbon monoxide (DLCO) interpretation needs the comparison of measured values to reference values. In 2017, the Global Lung Function Initiative published new reference values (GLI-2017) for DLCO, alveolar volume (VA) and transfer coefficient of the lung for carbon monoxide (KCO). We aimed to assess the applicability of GLI-2017 reference values for DLCO on a large population by comparing them to the European Community of Steel and Coal equations of 1993 (ECSC-93) widely used.
METHODS: In this retrospective study, spirometric indices, total lung capacity, DLCO, VA and KCO were measured in adults classified in 5 groups (controls, asthma, chronic bronchitis, cystic fibrosis, and interstitial lung diseases (ILD)). Statistical analysis comparing the 2 equations sets were stratified by sex.
RESULTS: 4180 tests were included. GLI-2017 z-scores of the 3 DLCO indices of the controls (n = 150) are nearer to 0 (expected value in a normal population) than ECSC-93 z-scores. All groups combined, in both genders, DLCO GLI-2017 z-scores and %predicted are significantly higher than ECSC z-scores and %predicted. In the ILD group, differences between the 2 equation sets depend on the DLCO impairment severity: GLI-2017 z-scores are higher than ECSC z-scores in patients with no or "mild" decrease in DLCO, but are lower in "moderate" or "severe" decrease.
CONCLUSION: GLI-2017 reference values for DLCO are more suitable to our population and influence the diagnostic criteria and severity definition of several lung diseases.

PMID: 33445178 [PubMed - as supplied by publisher]

PIPERACILLIN-TAZOBACTAM HYPERSENSITIVITY: A LARGE, MULTICENTRE ANALYSIS.

J Allergy Clin Immunol Pract. 2021 Jan 11;:

Authors: Casimir-Brown RS, Kayode OS, Siew LQC, Makris M, Tsilochristou O, Chytiroglou E, Nakonechna A, Kennard L, Rutkowski K, Mirakian R, Wagner A

Abstract
BACKGROUND: Piperacillin/tazobactam is a broad-spectrum penicillin. Hypersensitivity reactions are less commonly reported than with other penicillins except in patients with cystic fibrosis.
OBJECTIVE: Detailed clinical characterization of a patient cohort referred with suspected piperacillin-tazobactam hypersensitivity.
METHODS: Retrospective analysis of the demographic characteristics, clinical presentation, investigation and management of 87 patients presenting to 5 European allergy centers. Patients underwent skin prick and intradermal testing with piperacillin/tazobactam, major (penicilloyl-polylysine) and minor (sodium penilloate) determinants, amoxicillin, benzylpenicillin, flucloxacillin, co-amoxiclav, clavulanic acid and meropenem with immediate and where appropriate, delayed reading of tests. Skin test negative patients underwent drug provocation to piperacillin/tazobactam and/or other penicillins. A multistep protocol was used, depending on risk assessment.
RESULTS: Forty-eight of 87 (55%) patients were diagnosed with hypersensitivity to piperacillin/tazobactam with either positive skin or drug provocation tests, of whom 10 (21%) had a diagnosis of cystic fibrosis. Twenty-six (54%) patients presented with immediate and 22 (45%) with non-immediate hypersensitivity. Patients with cystic fibrosis predominantly presented with non-immediate hypersensitivity (70%). Reactions were severe in 52% of immediate reactors (Brown's anaphylaxis grade 3) and moderately severe (systemic involvement) in 75% of non-immediate reactors. The number of patients with negative skin tests tolerating re-introduction was comparable in immediate (80%) and non-immediate (88%) hypersensitivity. One third of patients were cross-sensitized to other penicillins. Cross-sensitization pattern raised the possibility of tazobactam allergy in 3 patients. In 21 patients selectively sensitized to piperacillin/tazobactam (12 immediate, 9 non immediate), tolerance to other beta lactams was demonstrated by drug provocation testing.
CONCLUSION: Piperacillin-tazobactam caused immediate and non-immediate hypersensitivity with similar frequency. The majority of patients were selectively sensitized and tolerated other penicillins. Some patients may be allergic to the beta-lactamase inhibitor only.

PMID: 33444815 [PubMed - as supplied by publisher]

A multicentre analysis of Clostridium difficile in persons with Cystic Fibrosis demonstrates that carriage may be transient and highly variable with respect to strain and level: Cystic Fibrosis and Clostridium difficile.

J Infect. 2021 Jan 11;:

Authors: Deane J, Fouhy F, Ronan NJ, Daly M, Fleming C, Eustace JA, Shanahan F, Flanagan ET, Dupont L, Harrison MJ, Haworth CS, Floto A, Rea MC, Ross RP, Stanton C, Plant BJ

Abstract
PURPOSE: Clostridium difficile has been reported to occur in the gastrointestinal tract of 50% of Cystic Fibrosis (CF) subjects, however, clinical C. difficile infection (CDI) is a rare occurrence in this cohort despite the presence of toxigenic and hypervirulent ribotypes. Here, we present the first longitudinal, multicentre analysis of C. difficile prevalence among adult CF subjects.
METHODOLOGY: Faecal samples were collected from adults with CF (selected based on confirmed Pseudomonas aeruginosa pulmonary colonisation) from Ireland, UK and Belgium as part of the CFMATTERS clinical research trial (grant No.603038) and from non-CF controls. Faecal samples were collected on enrolment, at three monthly intervals, during pulmonary exacerbation and three months post exacerbation. C. difficile was isolated from faecal samples by ethanol shocking followed by culturing on cycloserine cefoxitin egg yolk agar. Isolates were characterised in terms of ribotype, toxin type and antibiotic susceptibility to antibiotics routinely used in the treatment of CDI (metronidazole and vancomycin) and those implicated in induction of CDI (ciprofloxacin and moxifloxacin).
RESULTS: Prevalence of C. difficile among CF subjects in the three sites was similar ranging from 47-50% at baseline, while the healthy control cohort had a carriage rate of 7.1%. Including subjects who were positive for C. difficile at any time point there was a higher carriage rate of 71.4%, 66.7% and 63.2% in Ireland, UK, and Belgium, respectively. Ribotyping of 80 isolates from 45 CF persons, over multiple time points revealed 23 distinct ribotypes with two ribotypes (046 and 078) shared by all centres. The proportion of toxigenic isolates varied across the sites, ranging from 66.7% in Ireland to 52.9% in Belgium and 100% in the UK. Antibiotic susceptibility rates to vancomycin, metronidazole, ciprofloxacin and moxifloxacin was 100%, 97.5%, 1.3% and 63.8%, respectively.
CONCLUSIONS: This study demonstrates the highest carriage rate of C. difficile to date in a CF cohort. Longitudinal data shows that C. difficile can be a transient inhabitant of the CF gut, changing both in terms of strain and excretion rates.

PMID: 33444699 [PubMed - as supplied by publisher]