Clonal dissemination of Klebsiella pneumoniae ST258 harbouring KPC-2 in Argentina

AbstractThe present work describes the abrupt emergence of Klebsiella pneumoniae carbapenemase (KPC) and characterizes the first 79 KPC-producing enterobacteria from Argentina (isolated from 2006 to 2010). The emergence of blaKPC-2 was characterized by two patterns of dispersion: the first was the sporadic occurrence in diverse enterobacteria from distant geographical regions, harbouring plasmids of different incompatibility groups and blaKPC-2 in an unusual genetic environment flanked by ISKpn8-ΔblaTEM-1 and ISKpn6-like. blaKPC-2 was associated with IncL/M transferable plasmids; the second was the abrupt clonal spread of K. pneumoniae ST258 harbouring blaKPC-2 in Tn4401a

The Number of Shoulder and Elbow Questions on the Orthopedic In-Training Examination Is Increasing with Greater Emphasis on Critical Thinking over Recall

Background: It is critical for orthopedic surgery residents and residency programs to have a current understanding of the content and resources utilized by the Orthopedic In-Training Examination (OITE) to continuously guide study and educational efforts. This study presents an updated analysis of the shoulder and elbow section of the OITE. Methods: All OITE questions, answers, and references from 2013 to 2019 were reviewed. The number of shoulder and elbow questions per year was recorded, and questions were analyzed for topic, imaging modalities, cognitive taxonomy, and references. We compared our data to the results of a previous study that analyzed shoulder and elbow OITE questions from 2002 to 2007 to examine trends and changes in this domain overtime. Results: There were 177 shoulder and elbow questions (126 shoulder, 71.2%; 51 elbow, 28.8%) of 1863 OITE questions (9.5%) over a 7-year period. The most commonly tested topics included degenerative joint disease/stiffness/arthroplasty (31.6%), anatomy/biomechanics (16.9%), instability/athletic injury (15.3%), trauma (14.7%), and rotator cuff (13.6%). Half of all questions involved clinical management decisions (49.7%). A total of 417 references were cited from 56 different sources, the most common of which were the Journal of Shoulder and Elbow Surgery (23.3%), Journal of the American Academy of Orthopaedic Surgeons (20.4%), and Journal of Bone and Joint Surgery (American Volume) (16%). The average time lag from article publication to OITE reference was 7.7 years. Compared with a prior analysis from 2002 to 2007, there was a significant increase in the number of shoulder and elbow questions on the OITE (5.5% to 9.5%; P \u3c.001). Recent exams incorporated more complex multistep treatment questions (4.4% vs. 49.7%; P \u3c.001) and fewer recall questions (42.2% vs. 22%; P \u3c.001). There was a significant increase in the use of imaging modalities (53.3% vs. 79.1%; P \u3c.001). No significant differences in the distribution of question topics were found. Conclusions: The percentage of shoulder and elbow questions on the OITE has nearly doubled over the past decade with greater emphasis on critical thinking (eg, clinical management decisions) over recall of facts. These findings should prompt educators to direct didactic efforts (eg, morning conferences and journal club) toward case-based learning to foster critical thinking and clinical reasoning skills

Isolation of five Enterobacteriaceae species harbouring blaNDM-1 and mcr-1 plasmids from a single paediatric patient

In Argentina, NDM metallo-β-lactamase was first reported in 2013. By now, it has disseminated throughout the country in diverse Gram negative bacteria. Here, we report the case of a paediatric patient that underwent a 1-year hospitalisation due to erythrodermic psoriasis in 2014 and received multiple antimicrobial treatments. During his stay, five isolates were obtained from rectal swabs (rs) or blood culture (bc) suspicious of carbapenemase production: a K. quasipneumoniae subsp. quasipneumoniae (rs), Citrobacter freundii (rs), Escherichia coli (bc), Enterobacter cloacae (rs), and a Serratia marcescens (bc). The isolates were studied with broth microdilution, biparental conjugation and plasmid and whole genome sequencing (Illumina). All isolates harboured an 138,998-bp type 1 IncC plasmid that carried blaNDM-1, bleMBL, blaCMY-6, rmtC, aac(6')-Ib, and sul1 resistance genes. Additionally, the blaNDM-plasmids contained ISKpn8 an insertion sequence previously described as associated only to blaKPC. One isolate, a colistin-resistant E. coli, also carried a mcr-1-containing an IncI2 plasmid, which did not harbour additional resistance. The whole genome of K. quasipneumoniae subsp. quasipneumoniae isolate was fully sequenced. This isolate harboured, additionally to blaNDM, three plasmid-mediated quinolone resistance genes: qnrB4, qnrB52 and aac(6')-Ib-cr1. The E. cloacae isolate also harboured qnrA1. These findings alert to the underestimated horizontal dissemination of multidrug-resistant plasmids limiting treatment options with last resort antimicrobials

Pneumococcal lineages associated with serotype replacement and antibiotic resistance in childhood invasive pneumococcal disease in the post-PCV13 era: an international whole-genome sequencing study

Background: Invasive pneumococcal disease remains an important health priority owing to increasing disease incidence caused by pneumococci expressing non-vaccine serotypes. We previously defined 621 Global Pneumococcal Sequence Clusters (GPSCs) by analysing 20 027 pneumococcal isolates collected worldwide and from previously published genomic data. In this study, we aimed to investigate the pneumococcal lineages behind the predominant serotypes, the mechanism of serotype replacement in disease, as well as the major pneumococcal lineages contributing to invasive pneumococcal disease in the post-vaccine era and their antibiotic resistant traits. Methods: We whole-genome sequenced 3233 invasive pneumococcal disease isolates from laboratory-based surveillance programmes in Hong Kong (n=78), Israel (n=701), Malawi (n=226), South Africa (n=1351), The Gambia (n=203), and the USA (n=674). The genomes represented pneumococci from before and after pneumococcal conjugate vaccine (PCV) introductions and were from children younger than 3 years. We identified predominant serotypes by prevalence and their major contributing lineages in each country, and assessed any serotype replacement by comparing the incidence rate between the pre-PCV and PCV periods for Israel, South Africa, and the USA. We defined the status of a lineage as vaccine-type GPSC (≥50% 13-valent PCV [PCV13] serotypes) or non-vaccine-type GPSC (>50% non-PCV13 serotypes) on the basis of its initial serotype composition detected in the earliest vaccine period to measure their individual contribution toward serotype replacement in each country. Major pneumococcal lineages in the PCV period were identified by pooled incidence rate using a random effects model. Findings: The five most prevalent serotypes in the PCV13 period varied between countries, with only serotypes 5, 12F, 15B/C, 19A, 33F, and 35B/D common to two or more countries. The five most prevalent serotypes in the PCV13 period varied between countries, with only serotypes 5, 12F, 15B/C, 19A, 33F, and 35B/D common to two or more countries. These serotypes were associated with more than one lineage, except for serotype 5 (GPSC8). Serotype replacement was mainly mediated by expansion of non-vaccine serotypes within vaccine-type GPSCs and, to a lesser extent, by increases in non-vaccine-type GPSCs. A globally spreading lineage, GPSC3, expressing invasive serotypes 8 in South Africa and 33F in the USA and Israel, was the most common lineage causing non-vaccine serotype invasive pneumococcal disease in the PCV13 period. We observed that same prevalent non-vaccine serotypes could be associated with distinctive lineages in different countries, which exhibited dissimilar antibiotic resistance profiles. In non-vaccine serotype isolates, we detected significant increases in the prevalence of resistance to penicillin (52 [21%] of 249 vs 169 [29%] of 575, p=0·0016) and erythromycin (three [1%] of 249 vs 65 [11%] of 575, p=0·0031) in the PCV13 period compared with the pre-PCV period. Interpretation: Globally spreading lineages expressing invasive serotypes have an important role in serotype replacement, and emerging non-vaccine serotypes associated with different pneumococcal lineages in different countries might be explained by local antibiotic-selective pressures. Continued genomic surveillance of the dynamics of the pneumococcal population with increased geographical representation in the post-vaccine period will generate further knowledge for optimising future vaccine design. Funding: Bill & Melinda Gates Foundation, Wellcome Sanger Institute, and the US Centers for Disease Control.Fil: Lo, Stephanie W.. Wellcome Sanger Institute; Reino UnidoFil: Gladstone, Rebecca A.. Wellcome Sanger Institute; Reino UnidoFil: van Tonder, Andries J.. Wellcome Sanger Institute; Reino UnidoFil: Lees, John A.. University Of New York. School Of Medicine; Estados UnidosFil: du Plessis, Mignon. National Institute For Communicable Diseases; SudáfricaFil: Benisty, Rachel. Ben Gurion University of the Negev; IsraelFil: Givon Lavi, Noga. Ben Gurion University of the Negev; IsraelFil: Hawkins, Paulina A.. University of Emory. Rollins School of Public Health; Estados UnidosFil: Cornick, Jennifer E.. Malawi liverpool wellcome trust; MalauiFil: Kwambana Adams, Brenda. University College London; Estados UnidosFil: Law, Pierra Y.. University of Hong Kong; ChinaFil: Ho, Pak Leung. University of Hong Kong; ChinaFil: Antonio, Martin. Medical Research Council Unit The Gambia; GambiaFil: Everett, Dean B.. University of Edinburgh; Reino UnidoFil: Dagan, Ron. Ben Gurion University of the Negev; IsraelFil: Von Gottberg, Anne. National Institute For Communicable Diseases; SudáfricaFil: Klugman, Keith P.. University of Emory. Rollins School of Public Health; Estados UnidosFil: McGee, Lesley. Centers for Disease Control and Prevention; Estados UnidosFil: Breiman, Robert F.. University of Emory. Rollins School of Public Health; Estados UnidosFil: Bentley, Stephen D.. Wellcome Sanger Institute; Reino UnidoFil: Brooks, Abdullah W.. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Corso, Alejandra. The Global Pneumococcal Sequencing Consortium; Reino Unido. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas. Área de Antimicrobianos; ArgentinaFil: Davydov, Alexander. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Maguire, Alison. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Pollard, Andrew. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Kiran, Anmol. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Skoczynska, Anna. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Moiane, Benild. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Beall, Bernard. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Sigauque, Betuel. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Aanensen, David. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Lehmann, Deborah. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Faccone, Diego Francisco. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas. Área de Antimicrobianos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Pneumococcal lineages associated with serotype replacement and antibiotic resistance in childhood invasive pneumococcal disease in the post-PCV13 era: an international whole-genome sequencing study

Background: Invasive pneumococcal disease remains an important health priority owing to increasing disease incidence caused by pneumococci expressing non-vaccine serotypes. We previously defined 621 Global Pneumococcal Sequence Clusters (GPSCs) by analysing 20 027 pneumococcal isolates collected worldwide and from previously published genomic data. In this study, we aimed to investigate the pneumococcal lineages behind the predominant serotypes, the mechanism of serotype replacement in disease, as well as the major pneumococcal lineages contributing to invasive pneumococcal disease in the post-vaccine era and their antibiotic resistant traits. / Methods: We whole-genome sequenced 3233 invasive pneumococcal disease isolates from laboratory-based surveillance programmes in Hong Kong (n=78), Israel (n=701), Malawi (n=226), South Africa (n=1351), The Gambia (n=203), and the USA (n=674). The genomes represented pneumococci from before and after pneumococcal conjugate vaccine (PCV) introductions and were from children younger than 3 years. We identified predominant serotypes by prevalence and their major contributing lineages in each country, and assessed any serotype replacement by comparing the incidence rate between the pre-PCV and PCV periods for Israel, South Africa, and the USA. We defined the status of a lineage as vaccine-type GPSC (≥50% 13-valent PCV [PCV13] serotypes) or non-vaccine-type GPSC (>50% non-PCV13 serotypes) on the basis of its initial serotype composition detected in the earliest vaccine period to measure their individual contribution toward serotype replacement in each country. Major pneumococcal lineages in the PCV period were identified by pooled incidence rate using a random effects model. / Findings: The five most prevalent serotypes in the PCV13 period varied between countries, with only serotypes 5, 12F, 15B/C, 19A, 33F, and 35B/D common to two or more countries. The five most prevalent serotypes in the PCV13 period varied between countries, with only serotypes 5, 12F, 15B/C, 19A, 33F, and 35B/D common to two or more countries. These serotypes were associated with more than one lineage, except for serotype 5 (GPSC8). Serotype replacement was mainly mediated by expansion of non-vaccine serotypes within vaccine-type GPSCs and, to a lesser extent, by increases in non-vaccine-type GPSCs. A globally spreading lineage, GPSC3, expressing invasive serotypes 8 in South Africa and 33F in the USA and Israel, was the most common lineage causing non-vaccine serotype invasive pneumococcal disease in the PCV13 period. We observed that same prevalent non-vaccine serotypes could be associated with distinctive lineages in different countries, which exhibited dissimilar antibiotic resistance profiles. In non-vaccine serotype isolates, we detected significant increases in the prevalence of resistance to penicillin (52 [21%] of 249 vs 169 [29%] of 575, p=0·0016) and erythromycin (three [1%] of 249 vs 65 [11%] of 575, p=0·0031) in the PCV13 period compared with the pre-PCV period. / Interpretation: Globally spreading lineages expressing invasive serotypes have an important role in serotype replacement, and emerging non-vaccine serotypes associated with different pneumococcal lineages in different countries might be explained by local antibiotic-selective pressures. Continued genomic surveillance of the dynamics of the pneumococcal population with increased geographical representation in the post-vaccine period will generate further knowledge for optimising future vaccine design. / Funding: Bill & Melinda Gates Foundation, Wellcome Sanger Institute, and the US Centers for Disease Control

International links between Streptococcus pneumoniae vaccine serotype 4 sequence type (ST) 801 in Northern European shipyard outbreaks of invasive pneumococcal disease

Background: Pneumococcal disease outbreaks of vaccine preventable serotype 4 sequence type (ST)801 in shipyards have been reported in several countries. We aimed to use genomics to establish any international links between them. Methods: Sequence data from ST801-related outbreak isolates from Norway (n = 17), Finland (n = 11) and Northern Ireland (n = 2) were combined with invasive pneumococcal disease surveillance from the respective countries, and ST801-related genomes from an international collection (n = 41 of > 40,000), totalling 106 genomes. Raw data were mapped and recombination excluded before phylogenetic dating. Results: Outbreak isolates were relatively diverse, with up to 100 SNPs (single nucleotide polymorphisms) and a common ancestor estimated around the year 2000. However, 19 Norwegian and Finnish isolates were nearly indistinguishable (0–2 SNPs) with the common ancestor dated around 2017. Conclusion: The total diversity of ST801 within the outbreaks could not be explained by recent transmission alone, suggesting that harsh environmental and associated living conditions reported in the shipyards may facilitate invasion of colonising pneumococci. However, near identical strains in the Norwegian and Finnish outbreaks does suggest that transmission between international shipyards also contributed to those outbreaks. This indicates the need for improved preventative measures in this working population including pneumococcal vaccination

Detección de meticilino-resistencia en Staphylococcus aureus: Comparación de métodos convencionales y aglutinación con mrsa-Screen latex Methicillin resistance detection in Staphylococcus aureus: Comparison between conventional methods and Mrsa-Screen latex agglutination technique

Staphylococcus aureus meticilino-resistente (MRSA) es un patógeno que ha emergido en las últimas cuatro décadas causando tanto infecciones nosocomiales como de la comunidad. La rápida y precisa detección de MRSA es relevante para guiar una apropiada terapia antibiótica y evitar la diseminación nosocomial de MRSA.En este trabajo se evaluó la eficiencia de métodos convencionales para la detección de meticilino-resistencia como difusión por discos, CIM en medio sólido, screening de oxacilina, y el nuevo test de aglutinación MRSA-Screen latex sobre 100 aislamientos de S. aureus, 79 mecA positivos y 21 mecA negativos. El test de aglutinación MRSA-Screen latex (Denka Seiken, Niigata, Japón) detecta la presencia de la PLP-2a, producto del gen mecA en cepas de S. aureus. La detección del gen mecA por PCR se utilizó como gold standard para comparar los resultados de los diferentes métodos. La sensibilidad y especificidad fueron 97 y 100 % para el método de difusión, 97 y 95 % para la CIM en medio sólido, 100 y 100 % para el screening de oxacilina y 100 y 100 % para MRSA-Screen latex. Todos los métodos presentaron alta sensibilidad y especificidad, pero el “MRSA-Screen latex” mostró la ventaja de poder brindar un resultado confiable, equivalente a la PCR, en sólo 15 minutos.Methicillin-resistant Staphylococcus aureus (MRSA) is a significant pathogen that has emerged over the last four decades, causing both nosocomial and community-acquired infections. Rapid and accurate detection of methicillin resistance in S. aureus is important for the use of appropriate antimicrobial therapy and for the control of nosocomial spread of MRSA strains. We evaluated the efficiency of conventional methods for detection of methicillin resistance such as the disk diffusion, agar dilution, oxacillin agar screen test, and the latex agglutination test MRSA-Screen latex, in 100 isolates of S. aureus, 79 mecA positive and 21 mecA negative. The MRSA-Screen latex (Denka Seiken, Niigata, Japón), is a latex agglutination method that detects the presence of PLP-2a, product of mecA gene in S. aureus. The PCR of the mecA gene was used as the “gold standard” for the evaluation of the different methods tested. The percentages of sensitivity and specificity were as follows: disk difusión 97 and 100 %, agar dilution 97 and 95 %, oxacillin agar screen test 100 and 100 %, and MRSA-Screen latex, 100 and 100 %. All methods presented high sensitivity and specificity, but MRSA-Screen latex had the advantage of giving a reliable result, equivalent to PCR, in only 15 minutes

Prevalence of mef and ermB genes in invasive pediatric erythromycin-resistant Streptococcus pneumoniae isolates from Argentina Prevalencia de los genes mef y ermB en aislamientos invasivos de Streptococcus pneumoniae resistentes a eritromicina recuperados de pacientes pediátricos en Argentina

During the period 1993-2001, a total of 1,499 pneumococci isolates were recovered through the Argentinean surveillance of Streptococcus pneumoniae causing invasive disease in children under 6 years of age, 3.5% of which were erythromycin resistant. Among the 50 erythromycin-resistant strains available, 58% (n=29) harbored mefA/E genes (15 mefA, 30%; and 14 mefE, 28%), 34% (n=17) ermB, and 6% (n=3) both mefA/E plus ermB genes, while one isolate was negative for all the acquired genes studied. The England14-9 (42%), Poland6B-20 (20%) and Spain9v-3 (16%) clones were responsible for the emergence of pneumococcal macrolide resistance in pediatric population from Argentina.En el marco del programa de vigilancia regional SIREVA, se analizaron 1499 aislamientos de Streptococcus pneumoniae causantes de enfermedad invasiva en menores de 6 años, recuperados entre 1993 y 2001. Se detectó un 3,5% de resistencia a eritromicina. De los 50 aislamientos resistentes a eritromicina que pudieron ser estudiados, el 58% (n=29) tenían los genes mefA/E (15 mefA, 30% y 14 mefE, 28%), el 34% (n=17) el gen ermB y el 6% (n=3) la combinación de genes mefA/E y ermB. Sólo un aislamiento fue negativo para todos los genes analizados. Los clones internacionales England14-9, Poland6B-20 y Spain9v-3 representaron el 78% del total de aislamientos resistentes (42, 20 y 16%, respectivamente) y se consideraron los responsables de la emergencia de la resistencia a macrólidos entre los neumococos que afectan a la población pediátrica de Argentina

A simple test for the detection of KPC and metallo-b-lactamase carbapenemase- producing Pseudomonas aeruginosa isolates with the use of meropenem disks supplemented with aminophenylboronic acid, dipicolinic acid and cloxacillin

Abstract We evaluated the ability of the combination disk test (CDT) and the Modified Hodge Test (MHT) to discriminate between various carbapenemase-producing Pseudomonas aeruginosa isolates (KPC, n = 36; metallo-b-lactamase (MBL), n = 38) and carbapenemase non-producers (n = 75). For the CDT, the optimal inhibitor concentrations and cut-off values were: 600 lg of 3-aminophenylboronic acid (APB) per disk (an increment of ‡4 mm), 1000 lg of dipicolinic acid (DPA) per disk (an increment of ‡5 mm) and 3000 lg of cloxacillin per disk (an increment of ‡3 mm). APB had excellent sensitivity (97%) and specificity (97%) for the detection of KPC enzymes. DPA detected MBL enzymes with a sensitivity and specificity of 97% and 81%, respectively. The MHT resulted in a low sensitivity (78%) and specificity (57%). The CDT could be very useful in daily practice to provide fast and reliable detection of KPC and MBL carbapenemases among P. aeruginosa isolates. Detection of carbapenemase producers in the clinical laboratory is of major importance for the determination of appropriate therapeutic schemes and the implementation of infection control measures A panel of P. aeruginosa isolates (n = 149) were included. The carbapenemases represented were (n): KPC (36), VIM-2 (16), SPM-1 (8), VIM-11 (5), IMP-13 (5), and IMP-16 (4) (Pasteran et al., 49th ICAAC, 2009, Abstract 1003). The resistance mechanisms among carbapenemase non-producers were (n): wild type (6), narrow-spectrum-b-lactamases (2), extended-spectrum b-lactamases (7), cephalosporinase overproduction (7), efflux overproduction (15) and dual mechanisms (efflux plus cephalosporinase overproduction, 38). The isolates were from clinical sources. All strains corresponded to different pulsed-field gel electrophoresis types First, we evaluated the performance of carbapenemase screening by using meropenem ZIs. Meropenem ranges (in mm) were 6-9, 6-23 and 6-34 for KPC producers, MBL producers and carbapenemase non-producers, respectively