Biological factors of inflammation and methods of their detection

Inflammation is a complicated process occurring after a harmful stimuli or infection. During inflammation a large number of biochemical reactions and pathophysiological changes take place. These procedures are all induced by active biological compounds called mediators or chemokines. These molecules are derived from plasma and cells and are capable of performing the appropriate changes both on the endothelium and cells during the inflammatory process. Moreover, some of them have the ability to interact with each other. Today there are different methods to detect and quantitate these compounds. These techniques keep on evolving and improving. Which one is the most suitable depends on the researcher’s scientific aim. A standardized protocol was created in order to make MRU feasible in everyday use, based on protocols suggested by other researchers. Both T1 and T2 weighted images were obtained using the following sequences: 2D Τ2-weighted fat saturation, 3D single shot fast spin-echo (SSFSE/RARE), 2D Radial SSFSE and T1-weighted gradient LAVA (3D SPGR). In 16 out of the 21 cases the MRU images and data agreed with the previous diagnosis based on radionuclide and ultrasound studies. In 5 cases MRU provided additional information, altering or even overruling the previous diagnosis. These 5 cases are presented in this article

Spa diversity and genetic characterization of t127 methicillin-resistant Staphylococcus aureus in a tertiary Greek hospital

Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) causes severe community and hospital acquired infections. Identification of staphylococcal cassette chromosome mec (SCCmec), multilocus-sequence typing, and sequencing of S. aureus protein A (spa) gene are used for MRSA typing. The aim was to investigate the spa types of MRSA isolates in a tertiary hospital in Greece and analyse the whole genome sequences of two t127 MRSA isolates. Methods: Totally, 39 MRSA isolates collected from July 2019 to June 2020 in "Georgios Gennimatas" General Hospital of Thessaloniki, Greece, were included in the study. Identification and antimicrobial susceptibility testing were performed using VITEK II automated system, and spa typing was performed. A minimum spanning tree was used to display the spa type frequencies and the genetic distances among them. Two t127-MRSA isolates (IM-MRSA and PD-MRSA) were selected for WGS. Results: Six isolates (15.4%) were resistant to mupirocin, 18 (46.2%) to fusidic acid, three (7.7%) to vancomycin and two (5.1%) to teicoplanin. Twenty-two different spa types were detected, with t002, t003, and t422 being the most frequent (5/39, 12.8% each), followed by t1994 (4/39, 10.3%). The isolates presented high genetic diversity and, taking into account the time between hospital admission and sampling, intrahospital spread did not occur. Even the two t127 isolates were assigned to different sequence types, ST9-XII-t127 and ST1-IVa-t127. Plasmids and genes conferring antimicrobial resistance and virulence were also identified. Conclusions: Various spa types were identified and together with the information about the time between hospital admission and sampling supports polyclonal MRSA spread in the hospital excluding a nosocomial infection. WGS provides a more detailed analysis distinguishing even the isolates belonging to the same spa type

Molecular epidemiology of hospital infections in a tertiary hospital: study of the impact of infection control measures

Carbapenem-resistant Gram-negative bacteria (CRGNB) are endemic in Greece. Among CRGNB, carbapenem-resistant Klebsiella pneumoniae (CRKP), carbapenem-resistant Pseudomonas aeruginosa (CRPA) and carbapenem-resistant Acinetobacter baumannii (CRAB) are the most important, as they adversely affect the outcome and the duration of hospitalization, especially of severely ill and immunocompromised patients. The implementation of infection control measures (ICM) against CRBNB infections, as well as enhanced ICM (EICM) combined with the knowledge of CRGNB molecular epidemiology, can limit their dispersion in the hospital environment. Aim of the present thesis was to study the molecular epidemiology of CRKP, CRPA and CRAB strains, to evaluate the effectiveness of ICM and EICM on the containment of their spread and transmission and to detect the risk factors for CRGNB emergence in the Solid Organ Transplatation department (SOT), in the Intensive Care Unit (ICU) and in the Pediatric ICU (PICU) of Hippokration General Hospital of Thessaloniki. Material and Methods: The study in SOT included 209 patients (126 males-83 females) aged 6-78 years (median age 52 years), who were hospitalized in the department during March 2012-August 2013. The study in ICU included 300 patients (202 males-98 females) aged 15-95 years (median age 58 years) who were hospitalized during August 2012-November 2014. Finally, the study in the PICU included 130 patients (70 boys-60 girls) aged 0.1-14 years (median age 3 years) who were hospitalized during January 2013-November 2015. Each study included a retrospective and a prospective period. During the prospective period, an active surveillance program (ASP) was implemented and CRGNB colonization was tested through weekly taken rectal swabs. In addition, during the ASP, ICM (1st sub-period) and EICM (2nd sub-period) were applied, while staff compliance was recorded. Weekly incidence, prevalence and colonization pressure of CRGNB rectum colonization were calculated. Throughout the study, the incidence of carbapenem resistance and the incidence of infections as number / 1000 bed days (IBD) for CRKP, CRPA and CRAB were also calculated. Moreover, the centered moving average (CMA) of the leading moving average was estimated on a 4-week basis for incidence, prevalence and colonization pressure and a 4-month basis for CRGNB infections and carbapenem resistance rates. Identification and antimicrobial susceptibility testing were performed using the VITEK 2 automated system. CRKP, CRPA and CRAB strains were tested for the production of various β-lactamases and carbapenemases using phenotypic and molecular methods. Finally, the genotypic relatedness of the strains was investigated by pulsed-field gel electrophoresis (PFGE). Results: CRKP strains predominated in SOT and the CMA of CRKP infections increased (p<0.001). On the other hand, the CMA of CRAB infections decreased (p=0.028). During the 2nd sub-period of ASP, an increase in CMA prevalence and colonization pressure was observed (p<0.001), probably due to a large number of patients previously hospitalized in the ICU. However, the trend of the CMA for rectum incidence remained unchanged. Staff compliance with contact precautions improved from 1st to 2nd sub-period of ASP for both doctors (p=0.045) and nursing staff (p=0.041). The emergence of CRGNB was associated with age, prior hospitalization in the ICU, number of SOT admissions and liver transplantation. In PFGE analysis, the majority of K. pneumoniae strains producing K. pneumoniae carbapenemase (KPC) (KPKP) were clustered in one clonal type. Similarly, VIM-producing K. pneumoniae (VPKP) were also clustered in a single clonal type. VIM-producing CRPA strains were clustered in multiple clonal types. A KPC-producing CRPA strain was isolated for the first time in Greece. Among CRAB strains OXA-23-like producers predominated and presented clonal dispersion. In ICU, the CMA of CRKP and CRPA infections decreased (p=0.001 and p=0.043, respectively), while the CMA of CRAB infections increased (p<0.001). Resistance to carbapenems for each pathogen showed a similar trend. Throughout the whole prospective part of the study, the CMA of prevalence reduced (p=0.043), while the CMA of incidence, prevalence and colonization pressure decreased during the 2nd sub-period of ASP (p<0.001). Compliance with contact precautions improved for the medical and nursing staff (p=0.009 and p=0.001, respectively), as well as compliance with hand hygiene before aseptic procedure (p=0.027 and p=0.034, respectively). Central venous catheter (CVC), brain damage and the use of piperacillin-tazobactam were highlighted as independent risk factors for CRGNB emergence. KPKP strains displayed clonal dispersion as well as VPKP strains. CRKP strains producing OXA-48-like were clustered in multiple clones. Polyclonal distribution was also observed in CRPA strains and CRAB strains with OXA-23-like production. A CRPA strain harbouring concurrently KPC and VIM was isolated for the first time in Greece. CRAB strains prevailed in PICU. The CMA of CRKP infections decreased (p=0.046), while the CMA of CRPA infections increased (p<0.001). Throughout the whole prospective part of the study, the CMA of incidence, prevalence and colonization pressure reduced (p=0.029, p=0.006 and p=0.015, respectively) with a higher trend of decrease during the 2nd sub-period of ASP. Compliance with hand hygiene improved from the 1st to the 2nd sub-period of ASP both form medical and nursing staff before (p=0.032 and p=0.041, respectively) and after contact with the patient (p=0.011 and p=0.007, respectively). CVC was found to be an independent risk factor for CRGNB emergence. KPKP strains showed clonal dispersion, while the majority of CRPA did not produce any carbapenemase and were clustered in multiple clones. Double positive OXA-23-like and OXA-58-like producers prevailed and were clustered in two clonal types. In all three departments, the majority of KPKP strains were classified in the predominant "Greek hyper-epidemic clone". Moreover, VPKP strains showed clonal dispersion. VIM-producing CRPA strains were clustered into multiple clones. OXA-23-like producing CRAB predominated against OXA-58-like, and were clustered in three distinct clonal types. Conclusions: This study showed that containment of the spread of CRKP, CRPA and CRAB strains in an endemic environment can potentially be achieved. The awareness and study of the molecular epidemiology of these strains combined with the implementation of targeted EICM may have a mid-to-long-term effect on reducing the incidence of CRGNB. These results can constitute the basis for future studies focusing on the molecular epidemiology of CRGNB.Τα ανθεκτικά στις καρβαπενέμες Gram (-) βακτήρια (carbapenem-resistant Gram negative bacteria, CRGNB) είναι ενδημικά στην Ελλάδα. Από αυτά, η ανθεκτική στις καρβαπενέμες Klebsiella pneumoniae (carbapenem-resistant Klebsiella pneumoniae, CRKP), η ανθεκτική στις καρβαπενέμες Pseudomonas aeruginosa (carbapenem-resistant Pseudomonas aeruginosa, CRPA) και το ανθεκτικό στις καρβαπενέμες Acinetobacter baumannii (carbapenem-resistant Acinetobacter baumannii, CRAB) είναι τα πιο σημαντικά, καθώς επηρεάζουν δυσμενώς την έκβαση και τη διάρκεια νοσηλείας κυρίως των βαρέως πάσχοντων και ανοσοκατεσταλμένων ασθενών. Η εφαρμογή μέτρων περιορισμού των CRGNB λοιμώξεων (infection control measures, ICM), καθώς και εντατικοποιημένων ICM (enhanced ICM, EICM), σε συνδυασμό με τη γνώση της μοριακής επιδημιολογίας των CRGNB, μπορεί να περιορίσει τη διασπορά τους στο νοσοκομειακό περιβάλλον. Σκοπός της παρούσας διατριβής ήταν η μελέτη της μοριακής επιδημιολογίας στελεχών CRKP, CRPA και CRAB, η μελέτη της επίδρασης των ICM και EICM στον περιορισμό της εξάπλωσής τους, και η ανίχνευση παραγόντων κινδύνου εμφάνισης CRGNB στη Χειρουργική Κλινική Μεταμοσχεύσεων (ΧΚΜ), τη Μονάδα Ενατικής Θεραπείας (ΜΕΘ) και τη ΜΕΘ Παίδων (ΜΕΘ Π/Δ) του Ιπποκρατείου νοσοκομείου Θεσσαλονίκης. Υλικό και μέθοδοι: Στη μελέτη της ΧΚΜ συμπεριλήφθηκαν συνολικά 209 ασθενείς (126 άνδρες-83 γυναίκες) ηλικίας 6-78 ετών (διάμεση ηλικία 52 έτη), οι οποίοι νοσηλεύθηκαν στην κλινική κατά τη χρονική περίοδο Μάρτιος 2012-Αύγουστος 2013. Όσον αφορά τη ΜΕΘ, συμπεριλήφθηκαν συνολικά 300 ασθενείς (202 άνδρες-98 γυναίκες) ηλικίας 15-95 ετών (διάμεση ηλικία 58 έτη), οι οποίοι νοσηλεύθηκαν στη μονάδα κατά τη χρονική περίοδο Αύγουστος 2012-Νοέμβριος 2014. Τέλος, από τη ΜΕΘ Π/Δ επιλέχθηκαν συνολικά 130 ασθενείς (70 αγόρια-60 κορίτσια) ηλικίας 0,1-14 ετών (διάμεση ηλικία 3 έτη), οι οποίοι νοσηλεύθηκαν κατά τη χρονική περίοδο Ιανουάριος 2013-Νοέμβριος 2015. Σε κάθε κλινική η μελέτη περιλάμβανε αναδρομική και προοπτική περίοδο. Η προοπτική περίοδος περιλάμβανε πρόγραμμα ενεργητικής επιτήρησης (active surveillance program, ASP) των λοιμώξεων, με εβδομαδιαία λήψη δειγμάτων ορθού για έλεγχο αποικισμού από CRGNB. Κατά τη διάρκεια του ASP εφαρμόστηκαν ICM (1η υποπερίοδος) και EICM (2η υποπερίοδος) ενώ καταγράφονταν και η συμμόρφωση του προσωπικού. Έγινε υπολογισμός της εβδομαδιαίας επίπτωσης, του επιπολασμού και της πίεσης αποικισμού στο ορθό. Σε όλη τη διάρκεια της μελέτης υπολογίστηκαν τα ποσοστά αντοχής στις καρβαπενέμες και η επίπτωση των λοιμώξεων ως αριθμός/1000 ημέρες νοσηλείας (infections/1000 bed days, IBD) για τα CRKP, CRPA και CRAB. Επίσης, υπολογίστηκε ο κεντρικός μέσος όρος (centered moving average, CMA) του προπορευόμενου κινούμενου μέσου όρου σε 4-εβδομαδιαία και 4-μηνιαία βάση. Η ταυτοποίηση και δοκιμασία ευαισθησίας στα αντιμικροβιακά έγινε με το αυτοματοποιημένο σύστημα VITEK 2. Τα στελέχη CRKP, CRPA και CRAB ελέγχθηκαν με φαινοτυπικές και μοριακές μεθόδους για την παραγωγή διαφόρων β-λακταμασών και καρβαπενεμασών. Ο έλεγχος της γενετικής συγγένειας των στελεχών έγινε με ηλεκτροφόρηση σε παλλόμενο πεδίο (pulsed-field gel electrophoresis, PFGE). Αποτελέσματα: Στη ΧΚΜ επικράτησαν τα στελέχη CRKP, με τον CMA των CRKP λοιμώξεων να αυξάνεται (p<0,001). Αντίθετα, ο CMA των CRAB λοιμώξεων ελαττώθηκε (p=0,028). Κατά τη 2η υποπερίοδο του ASP παρατηρήθηκε αύξηση του CMA του επιπολασμού και της πίεσης αποικισμού (p<0,001) πιθανώς λόγω μεγάλης εισαγωγής ασθενών από τη ΜΕΘ. Ωστόσο, η τάση της επίπτωσης παρέμεινε αμετάβλητη. Η συμμόρφωση του προσωπικού με τις προφυλάξεις επαφής βελτιώθηκε μεταξύ 1ης και 2ης υποπεριόδου του ASP, τόσο για τους ιατρούς (p=0,045) όσο και για το νοσηλευτικό προσωπικό (p=0,041). Η εμφάνιση CRGNB συσχετίστηκε με την ηλικία, την προηγούμενη νοσηλεία στη ΜΕΘ, τον αριθμό εισαγωγών και τη μεταμόσχευση ήπατος. Τα στελέχη K. pneumoniae που παρήγαγαν Klebsiella pneumoniae carbapenemase (KPC) (KPC-producing Klebsiella pneumoniae, KPKP) κατατάχθηκαν στην πλειοψηφία τους σε έναν κλώνο, όπως σε έναν κλώνο κατατάχθηκαν και τα στελέχη που παρήγαγαν VIM (VIM-producing Klebsiella pneumoniae, VPKP). Τα στελέχη CRPA με παραγωγή VIM κατατάχθηκαν σε πολλαπλούς κλώνους, ενώ απομονώθηκε για πρώτη φορά στέλεχος CRPA με παραγωγή KPC. Στα CRAB κυριάρχησαν αυτά που παρήγαγαν την καρβαπενεμάση OXA-23-like και παρουσίασαν κλωνική διασπορά. Στη ΜΕΘ, ο CMA των CRKP και CRPA λοιμώξεων ελαττώθηκε (p=0,001 και p=0,043, αντίστοιχα), ενώ για τα CRAB αυξήθηκε (p<0,001). Αντίστοιχη μεταβολή παρουσίασαν και τα ποσοστά αντοχής στις καρβαπενέμες. Στο σύνολο της μελέτης ο CMA του επιπολασμού μειώθηκε (p=0,043), ενώ κατά τη 2η υποπερίοδο του ASP η επίπτωση, ο επιπολασμός και η πίεση αποικισμού μειώθηκαν (p<0,001). Η συμμόρφωση με τις προφυλάξεις επαφής βελτιώθηκε για το ιατρικό και νοσηλευτικό προσωπικό (p=0,009 και p=0,001, αντίστοιχα), όπως και η συμμόρφωση με την υγιεινή των χεριών πριν από καθαρό ή άσηπτο χειρισμό (p=0,027 και p=0,034, αντίστοιχα). Η ύπαρξη κεντρικού φλεβικού καθετήρα (central venous catheter, CVC), η κρανιοεγκεφαλική κάκωση και η χρήση πιπερακιλλίνης-ταζομπακτάμης αναδείχθηκαν ως ανεξάρτητοι παράγοντες κινδύνου εμφάνισης CRGNB. Τα στελέχη KPKP παρουσίασαν κλωνική διασπορά όπως και τα στελέχη VPKP. Στελέχη CRKP με παραγωγή OXA-48-like κατατάχθηκαν σε πολλαπλούς κλώνους. Πολυκλωνική κατανομή παρουσίασαν επίσης τα στελέχη CRPA και τα στελέχη CRAB με παραγωγή OXA-23-like. Για πρώτη φορά απομονώθηκε στην Ελλάδα στέλεχος CRPA με ταυτόχρονη παραγωγή KPC και VIM.Στη ΜΕΘ Π/Δ επικράτησαν τα στελέχη CRAB. Ο CMA των CRKP λοιμώξεων μειώθηκε (p=0,046), ενώ των CRPA λοιμώξεων αυξήθηκε (p<0,001). Ο CMA της επίπτωσης, του επιπολασμού και της πίεσης αποικισμού μειώθηκε στο σύνολο της μελέτης (p=0,029, p=0,006 και p=0,015, αντίστοιχα) με μεγαλύτερη τάση μείωσης κατά τη 2η υποπερίοδο του ASP. Η συμμόρφωση με την υγιεινή των χεριών μεταξύ 1ης και 2ης υποπεριόδου του ASP, βελτιώθηκε για το ιατρικό και νοσηλευτικό προσωπικό πριν (p=0,032 και p=0,041, αντίστοιχα) και μετά την επαφή με τον ασθενή (p=0,011 και p=0,007, αντίστοιχα). Η ύπαρξη CVC αναδείχθηκε ως ανεξάρτητος παράγοντας εμφάνισης CRGNB. Τα KPKP εμφάνισαν κλωνική διασπορά, ενώ τα CRPA που μελετήθηκαν στην πλειοψηφία τους δεν παρήγαγαν κάποια καρβαπενεμάση και κατατάχθηκαν σε πολλαπλούς κλώνους. Τα διπλά θετικά OXA-23-like και OXA-58-like επικράτησαν, κατατασσόμενα σε δύο κλώνους. Στο σύνολο των τριών κλινικών, η πλειοψηφία των KPKP κατατάχθηκε στον κυρίαρχο «ελληνικό υπερεπιδημικό κλώνο», όπως και τα VPKP που εμφάνισαν κλωνική διασπορά. Τα CRPA με παραγωγή VIM ταξινομήθηκαν σε πολλαπλούς κλώνους. Τα CRAB με παραγωγή OXA-23-like κυριάρχησαν έναντι των ΟΧΑ-58-like, και ταξινομήθηκαν σε τρεις βασικούς κλώνους. Συμπεράσματα: Η παρούσα μελέτη έδειξε ότι ο έλεγχος της εξάπλωσης των CRKP, CRPA και CRAB σε ένα ενδημικό περιβάλλον, μπορεί να επιτευχθεί κατά περίπτωση. Η γνώση και η μελέτη της μοριακής επιδημιολογίας των στελεχών αυτών στο νοσοκομειακό περιβάλλον σε συνδυασμό με την εφαρμογή στοχευμένων EICM μπορεί να φέρει μεσομακροπρόθεσμο αποτέλεσμα στην ελάττωση της επίπτωσης των CRGNB. Τα αποτελέσματα αυτά μπορεί να αποτελέσουν βάση για μελλοντικές έρευνες της μοριακής επιδημιολογίας των CRGNB

Carbapenem-Resistant Klebsiella pneumoniae: Virulence Factors, Molecular Epidemiology and Latest Updates in Treatment Options

Klebsiella pneumoniae is a Gram-negative opportunistic pathogen responsible for a variety of community and hospital infections. Infections caused by carbapenem-resistant K. pneumoniae (CRKP) constitute a major threat for public health and are strongly associated with high rates of mortality, especially in immunocompromised and critically ill patients. Adhesive fimbriae, capsule, lipopolysaccharide (LPS), and siderophores or iron carriers constitute the main virulence factors which contribute to the pathogenicity of K. pneumoniae. Colistin and tigecycline constitute some of the last resorts for the treatment of CRKP infections. Carbapenemase production, especially K. pneumoniae carbapenemase (KPC) and metallo-&beta;-lactamase (MBL), constitutes the basic molecular mechanism of CRKP emergence. Knowledge of the mechanism of CRKP appearance is crucial, as it can determine the selection of the most suitable antimicrobial agent among those most recently launched. Plazomicin, eravacycline, cefiderocol, temocillin, ceftolozane&ndash;tazobactam, imipenem&ndash;cilastatin/relebactam, meropenem&ndash;vaborbactam, ceftazidime&ndash;avibactam and aztreonam&ndash;avibactam constitute potent alternatives for treating CRKP infections. The aim of the current review is to highlight the virulence factors and molecular pathogenesis of CRKP and provide recent updates on the molecular epidemiology and antimicrobial treatment options

Carbapenem-Resistant <i>Klebsiella pneumoniae</i>: Virulence Factors, Molecular Epidemiology and Latest Updates in Treatment Options

Klebsiella pneumoniae is a Gram-negative opportunistic pathogen responsible for a variety of community and hospital infections. Infections caused by carbapenem-resistant K. pneumoniae (CRKP) constitute a major threat for public health and are strongly associated with high rates of mortality, especially in immunocompromised and critically ill patients. Adhesive fimbriae, capsule, lipopolysaccharide (LPS), and siderophores or iron carriers constitute the main virulence factors which contribute to the pathogenicity of K. pneumoniae. Colistin and tigecycline constitute some of the last resorts for the treatment of CRKP infections. Carbapenemase production, especially K. pneumoniae carbapenemase (KPC) and metallo-β-lactamase (MBL), constitutes the basic molecular mechanism of CRKP emergence. Knowledge of the mechanism of CRKP appearance is crucial, as it can determine the selection of the most suitable antimicrobial agent among those most recently launched. Plazomicin, eravacycline, cefiderocol, temocillin, ceftolozane–tazobactam, imipenem–cilastatin/relebactam, meropenem–vaborbactam, ceftazidime–avibactam and aztreonam–avibactam constitute potent alternatives for treating CRKP infections. The aim of the current review is to highlight the virulence factors and molecular pathogenesis of CRKP and provide recent updates on the molecular epidemiology and antimicrobial treatment options

Genetic Characterization of Carbapenem-Resistant <i>Klebsiella pneumoniae</i> Clinical Isolates in a Tertiary Hospital in Greece, 2018–2022

Background: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a serious public health issue. The study aimed to identify the antimicrobial resistance and accessory genes, the clonal relatedness, and the evolutionary dynamics of selected CRKP isolates recovered in an adult and pediatric intensive care unit of a tertiary hospital in Greece. Methods: Twenty-four CRKP isolates recovered during 2018–2022 were included in the study. Next-generation sequencing was performed using the Ion Torrent PGM Platform. The identification of the plasmid content, MLST, and antimicrobial resistance genes, as well as the comparison of multiple genome alignments and the identification of core genome single-nucleotide polymorphism sites, were performed using various bioinformatics software. Results: The isolates belonged to eight sequence types: 11, 15, 30, 35, 39, 307, 323, and 512. A variety of carbapenemases (KPC, VIM, NDM, and OXA-48) and resistance genes were detected. CRKP strains shared visually common genomic regions with the reference strain (NTUH-K2044). ST15, ST323, ST39, and ST11 CRKP isolates presented on average 17, 6, 16, and 866 recombined SNPs, respectively. All isolates belonging to ST15, ST323, and ST39 were classified into distinct phylogenetic branches, while ST11 isolates were assigned to a two-subclade branch. For large CRKP sets, the phylogeny seems to change approximately every seven SNPs. Conclusions: The current study provides insight into the genetic characterization of CRKP isolates in the ICUs of a tertiary hospital. Our results indicate clonal dispersion of ST15, ST323, and ST39 and highly diverged ST11 isolates

Genetic characterization of two methicillin-resistant Staphylococcus aureus spa type t127 strains isolated from workers in the dairy production chain in Greece

Methicillin-resistant Staphylococcus aureus (MRSA) constitutes a constant threat for the public health. Aim of the present study was to analyse the whole genome sequences of two MRSA strains belonging to Staphylococcus protein A (spa) type t127 isolated from humans working in two distantly located dairy production farms in Greece. MRSA strains were isolated from the nasal cavity of a food handler in a milk industry in Epirus, northwestern Greece (E-MRSA), and a person working in a cattle farm in Thrace, northeastern Greece (T-MRSA). Whole genome sequences taken using next generation sequencing were analysed for resistance and virulence genes applying various bioinformatic tools. Both isolates were assigned to ST1-IVa-t127 type, and they were transferring genes conferring resistance to tetracycline, beta-lactams, and aminoglycosides; T-MRSA was carrying additional genes leading to macrolide, lincosamide and streptogramin B (MLSB) resistance. Both isolates were carrying three plasmid replicon types, reps, rep7 and rep16, while T-MRSA harboured also rep10 and rep15. E-MRSA carried scn and sak genes which were absent from T-MRSA. In conclusion, the genetic characterization of two unrelated ST1-IVa-t127 MRSA strains isolated from humans in close contact with livestock in Greece can be used as basis for further epidemiological and evolutionary studies

Changes in molecular epidemiology of carbapenem-resistant Klebsiella pneumoniae in the intensive care units of a Greek hospital, 2018-2021

The spread of multi-drug resistant (MDR) Gram-negative bacteria, including Klebsiella pneumoniae, constitutes a global threat. The most frequent mechanism of acquired carbapenem resistance is the production of carbapenemases, especially KPC, NDM, VIM, IMP and OXA-48. We analyzed the epidemiological trend of carbapenem resistance genes of carbapenem-resistant K. pneumoniae (CRKP) strains isolated from critically ill patients in a Greek tertiary hospital.The study included 150 CRKP isolates collected from 116 (77.4%) patients hospitalized in the adult ICU and 17 (11.3%) each in the pediatric and the two neonatal ICUs between March 2018 and March 2021. Identification and antimicrobial susceptibility testing were performed using VITEK-2. A multiplex lateral flow immunoassay was used for the detection of carbapenemases, while the detection of bla(VIM), bla(KPC), bla(NDM), bla(IMP) and bla(OXA-)(48)(-like) genes was achieved by multiplex PCR.The bla(NDM) was mainly detected in adults (54/116, 46.9%), while in children the most often detected gene was bla(KPC), (24/34, 70.6%). The predominant carbapenem resistance gene during 2018-2019 was bla(KPC) alone or in combination with bla(VIM), reaching 44.4% in 2019, while during 2020-2021 the detection of bla(NDM) prevailed significantly, reaching 45.5 and 60.7% for 2020 and 2021, respectively.A shift in the molecular epidemiology of CRKP was seen during 2018-2021, which is probably associated with the recent excessive empiric use of newer antimicrobials. Surveillance studies and proper and strict implementation of infection control measures are highly needed to decrease the spread of MDR bacteria, including CRKP

Development and Validation of the Life for Low Vision Questionnaire (LIFE4LVQ) Using Rasch Analysis: A Questionnaire Evaluating Ability and Independence

Low vision (LV) has a substantial impact on an individual’s daily functionality and patient-reported outcome measures (PROMs) are increasingly incorporated into the evaluation of this problem. The objective of this study was to describe the design of the new “Life for Low Vision Questionnaire (LIFE4LVQ)”, as a measure of daily functionality in LV and to explore its psychometric properties. A total of 294 participants completed the LIFE4LVQ and the data were subjected to Rasch analysis to determine the psychometric properties of the questionnaire, including response category ordering, item fit statistics, principal component analysis, precision, differential item functioning, and targeting. Test–retest reliability was evaluated with an interval of three weeks and intraclass correlation coefficients (ICC) were used. The correlation between the questionnaire score and Best Corrected Visual Acuity (BCVA) was examined using Spearman’s correlation coefficient. Rasch analysis revealed that for most items the infit and outfit mean square fit values were close to 1, both for the whole scale and its subscales (ability and independence). The separation index for person measures was 5.18 with a reliability of 0.96, indicating good discriminant ability and adequate model fit. Five response categories were found for all items. The ICC was 0.96 (p < 0.001; 95% CI, 0.93–0.98), suggesting excellent repeatability of the measure. Poorer BCVA was significantly associated with worse scores (rho = 0.559, p < 0.001), indicating excellent convergent validity. The functional, 40-item LIFE4LVQ proved to be a reliable and valid tool that effectively measures the impact of LV on ability and independence