scholarly journals Dissemination of imipenem-resistant Acinetobacter baumannii strains carrying the ISAba1–bla OXA-23 genes in a Chinese hospital

2007 ◽  
Vol 56 (8) ◽  
pp. 1076-1080 ◽  
Author(s):  
Hua Zhou ◽  
Bo-Rui Pi ◽  
Qing Yang ◽  
Yun-Song Yu ◽  
Ya-Gang Chen ◽  
...  
Keyword(s):  
Intensive Care Unit ◽  
Acinetobacter Baumannii ◽  
Environmental Isolates ◽  
Hospital Units ◽  
Wide Range ◽  
Polymyxin E ◽  
Encoding Gene ◽  
Almost All ◽  
Resistance Rates ◽  
Encoding Genes

An outbreak of 95 clinical infections with imipenem-resistant Acinetobacter baumannii in a Chinese hospital was investigated and the carbapenemase-encoding genes and their relationship with ISAba1 of these and a further 16 isolates recovered from the intensive care unit (ICU) environment were analysed. Almost all isolates were resistant to a wide range of antimicrobials; the lowest resistance rates were found for polymyxin E (17.1 %), cefoperazone/sulbactam (30.6 %) and ampicillin/sulbactam (67.6 %). Six pattern types defined by DNA macrorestriction patterns were distinguished among the clinical isolates with dissemination of pattern A (50 isolates) to patients in seven hospital units and pattern B (35 isolates) to eight units; the environmental isolates from ICUs were also of pattern A. All isolates were positive for the bla OXA-66 and bla OXA-23 genes. The OXA-23-encoding gene was located 34 bp downstream of ISAba1. No plasmids were detected and conjugal transfer of resistance was not demonstrated. The bla OXA-23 probe hybridized with 200 and 220 kb ApaI chromosomal fragments for type patterns A and B, respectively.

scholarly journals Clonal spread of PER-1 and OXA-23 producing extensively drug resistant Acinetobacter baumannii during an outbreak in a burn intensive care unit in Tunisia

2020 ◽  
Author(s):  
Aymen Mabrouk ◽  
Yosra Chebbi ◽  
Anis Raddaoui ◽  
Asma Krir ◽  
Amen Allah Messadi ◽  
...  
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Acinetobacter Baumannii ◽  
Genetic Relatedness ◽  
Burn Patients ◽  
Drug Resistant ◽  
Extensively Drug Resistant ◽  
Total Dna ◽  
Clonal Spread ◽  
Encoding Genes

AbstractExtensively drug resistant Acinetobacter baumannii (XDR-Ab), has emerged as an important pathogen in several outbreaks. The aim of our study was to investigate the eventual genetic relatedness of XDR-Ab strains recovered from burn patients and environment sites in the largest Tunisian Burn Intensive Care Unit (BICU) and to characterize β-lactamase encoding genes in these strains. Between March 04th, 2019 and April 22nd, 2019 an outbreak of XDR-Ab was suspected. Environmental screening was done. All isolates were screened by simplex PCR for β-lactamase genes. Genetic relatedness was determined by pulsed field gel electrophoresis (PFGE) of ApaI-digested total DNA. During the study period, 21 strains of A. baumannii were isolated in burn patients, mainly in blood culture (n = 7) and central vascular catheter (n = 6). All strains were susceptible to colistin but resistant to imipenem (n = 23), ciprofloxacin (n = 23), amikacin (n = 22), tigecyclin (n = 5) and rifampicin (n = 4). The blaOXA-51-like, blaOXA23, and blaADC genes were present in all strains. These resistance determinants were associated with blaPER-1 in 10 strains. The ISAba1 was inserted upstream of blaOXA-23 in all isolates. PFGE revealed two major clusters A (n = 11) and B (n = 5). This is the first description in Tunisia of clonally related PER-1 producing XDR-Ab in burn patients with probable environmental origin.

scholarly journals Dissemination of Plasmid-Mediated Aminoglycoside-Modifying Enzymes Among MDR Acinetobacter baumannii Isolates from a Tertiary Care Egyptian Hospital

2020 ◽  
Vol 14 (1) ◽  
pp. 98-106
Author(s):  
Mahmoud M. Tawfick ◽  
Hamada F. Rady ◽  
Mervat I. El-Borhamy ◽  
Anwar D. Maraqa
Keyword(s):  
Acinetobacter Baumannii ◽  
Tertiary Care ◽  
Multidrug Resistant ◽  
Resistance Rate ◽  
Care Hospital ◽  
Aminoglycoside Resistance ◽  
Antimicrobial Susceptibility Pattern ◽  
Pcr Method ◽  
Resistance Rates ◽  
Encoding Genes

Background: Acinetobacter baumannii is one of the most challenging multidrug-resistant (MDR) nosocomial pathogens worldwide. Aminoglycosides are used for the treatment of A. baumannii infections, however, resistance to aminoglycosides is currently emerging, limiting therapeutic choices. Objective: In this study, the prevalence of aminoglycoside resistance and plasmid-mediated mechanisms of aminoglycoside resistance were investigated in A. baumannii clinical isolates collected from ICU patients at a tertiary care hospital in Egypt. Methods: The automated Vitek 2 system was used to identify A. baumannii species and determination of the antimicrobial susceptibility pattern. The identification of A. baumannii was confirmed by the detection of the blaOXA-51-like gene intrinsic to this species. Minimum Inhibitory Concentration (MIC) of gentamicin was determined using E-test following the CLSI breakpoints. Isolates were screened for the prevalence and diversity of the plasmid-carried aminoglycoside-modifying enzymes encoding genes aacC1, aadA1, aadB and aphA6. For genetic diversity analysis, the ERIC-PCR method was performed. Results: All A. baumannii isolates were MDR with high resistance rates to tested antimicrobials. The resistance rate to gentamicin was 92.9% with elevated MICs (≥ 32 μg/mL). The gentamicin-resistant isolates harboured one or more of the studied genes with the prevalence of aphA6 (81%). ERIC-based genotyping revealed that there was no evidence of A. baumannii clonal dissemination among isolates. Conclusion: The study concluded that MDR A. baumannii isolates were highly resistant to gentamicin. The plasmid-carried aminoglycoside-modifying enzymes encoding genes were disseminated among isolates with the AphA6 gene, which was the most prevalent one. The acquisition of more than one aminoglycoside resistance gene was associated with an elevated MIC of gentamicin. Thus, regular surveillance studies of the emerging resistance to antimicrobials and strict measures to control the dissemination of resistance determinants genes are warranted.

scholarly journals Insights on carbapenem-resistant Acinetobacter baumannii

2021 ◽  
Vol 65 (1) ◽  
pp. 85-92
Author(s):  
Matthew Gavino Donadu ◽  
Stefania Zanetti ◽  
Ádám László Nagy ◽  
Ibrahim Barrak ◽  
Márió Gajdács
Keyword(s):  
Public Health ◽  
Acinetobacter Baumannii ◽  
Efflux Pump ◽  
Public Health Issue ◽  
Carbapenem Resistant ◽  
Wide Range ◽  
Effective Choice ◽  
Phenotypic Methods ◽  
Resistance Rates ◽  
Critical Public Health

Acinetobacter baumannii (A. baumannii) is an important nosocomial pathogen, which may be a causative agent in a wide-range of human pathologies. Carbapenems are usually considered the last safe and effective choice of drugs for the treatment of Gram-negative infections. The emergence of carbapenem-resistant A. baumannii (CRAB) is a critical public health issue as they leave clinicians with limited therapeutic options. In this study, phenotypic methods were used to characterize sixty-two (n = 62) A. baumannii isolates, which were included based on their suspected non-susceptibility to meropenem. Minimum inhibitory concentrations (MICs) of meropenem, levofloxacin, gentamicin, sulfamethoxazole/trimethoprim, tigecycline were determined using E-tests, while colistin MICs were determined using broth microdilution. The isolates were subjected to the modified Hodge test (MHT), the modified carbapenem-inactivation method (mCIM) and the imipenem/EDTA combined disk test (CDT). Efflux pump overexpression was studied using agar plates containing phenylalanine-arginine β-naphthylamide (PAβN). Assessment of biofilm-formation was carried out using the crystal violet tube-adherence method. 64.5% of the strains showed meropenem MICs in the resistant range (>8 mg/L), resistance rates were similarly high to the other tested antibiotics. The MHT and mCIM assay were positive in 79.0% and 67.7% of cases, respectively; the presence of an MBL was suggested for 29.0% of isolates. Efflux-pump overexpression was seen in 12.9% of isolates. 54.8% of the isolates were characterized as strong biofilm-producers. Microbiology laboratories have an important role in differentiating the distinct mechanisms by which these pathogens develop the CRAB phenotype, as plasmid-borne carbapenemases are significant from the standpoint of public health microbiology.

scholarly journals Increasing carbapenem resistance due to the clonal dissemination of oxacillinase (OXA-23 and OXA-58)-producing Acinetobacter baumannii: report from the Turkish SENTRY Program sites

2008 ◽  
Vol 57 (12) ◽  
pp. 1529-1532 ◽  
Author(s):  
Deniz Gur ◽  
Volken Korten ◽  
Serhat Unal ◽  
Lalitagauri M. Deshpande ◽  
Mariana Castanheira
Keyword(s):  
Acinetobacter Baumannii ◽  
Antimicrobial Agents ◽  
Carbapenem Resistance ◽  
Surveillance Program ◽  
Carbapenem Resistant ◽  
Medical Institutions ◽  
Antimicrobial Surveillance ◽  
Resistant Strains ◽  
Resistance Rates ◽  
Encoding Genes

A significant increase in carbapenem-resistance rates among Acinetobacter baumannii isolates collected in two Turkish medical centres was detected in the 2000–2006 period (20–60 %) by the SENTRY Antimicrobial Surveillance Program. Carbapenem-resistant strains from 2006 were evaluated for the presence of encoding genes and epidemic clonality. OXA-58-like and OXA-23-like carbapenemase-producing strains were detected in both medical institutions. Seventeen out of 18 strains from Ankara were positive for bla OXA-58 primers and belonged to the same clone, whilst 26 isolates (25 from Istanbul and one from Ankara) harboured bla OXA-23-like genes and showed identical or similar PFGE patterns. Isolates producing OXA-23-like carbapenemases were more resistant than OXA-58-like carbapenemase producers to non-carbapenem antimicrobial agents. Carbapenem resistance in these institutions was observed to be largely driven by the dissemination of clones producing OXA-type carbapenemases.

scholarly journals Phenotypic and genotypic characterization of multidrug-resistant Acinetobacter baumannii isolated in Algerian hospitals

2020 ◽  
Vol 14 (12) ◽  
pp. 1395-1401
Author(s):  
Nabila Benamrouche ◽  
Ourida Lafer ◽  
Lahcen Benmahdi ◽  
Akila Benslimani ◽  
Wahiba Amhis ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Intensive Care ◽  
Acinetobacter Baumannii ◽  
Multidrug Resistant ◽  
Phenotypic Characterization ◽  
Resistant Strains ◽  
Almost All ◽  
Encoding Genes ◽  
Phenotypic And Genotypic Characterization

Introduction: The aim of this study was to investigate the drug-resistance and the molecular characterization of carbapenemases, ESBL, and aminoglycoside-modifying enzymes among Acinetobacter baumannii clinical isolates in Algerian hospitals. Methodology: A total of 92 A. baumannii isolates were collected between 2012 and 2016. Antimicrobial susceptibility testings were performed for β-lactams, aminoglycosides, fluoroquinolones, trimethoprim-sulfamethoxazole, rifampicin and colistin. The phenotypic characterization of β-lactamases was investigated. For 30 randomly targeted strains, the carriage of the carbapenemases, ESBL and aminoglycoside-modifying enzymes -encoding genes was determined by PCR. Sequencing was carried out for carbapenemases and ESBL genes. Results: Most of the 92 isolates studied were recovered from hospitalized patients (93.5%) and were mainly from intensive care units (51.1%) and orthopedics (19.6%). The strains were collected primarily from low respiratory tract (33.7%), wounds (23.9%) and urine (16.3%). Multidrug-resistant A. baumannii strains were prevalent (96.7%). High rates of resistance were observed for almost all antibiotics tested (>70%) excluding rifampicin (7.6%) and colistin (5.4%). For the five colistin-resistant strains, MICs ranged between 4 and 128 µg/mL. Positive MBL (83.7%) and ESBL (23.9%) strains were identified. Regarding β-lactams, the blaNDM and both blaSHV and blaCTX-M1 genes were detected in five and two strains respectively. Sequencing of the genes revealed the presence of blaNDM-1, blaCTX-M-15, and blaSHV-33. For aminoglycosides, aac(6’)-Ib, ant(2’’)-I and aph(3’)-VI genes were detected in three, seven and six strains respectively. Conclusions: Here, we report the first co-occurrence of extended-spectrum β-lactamases SHV-33 and CTX-M-15, the carbapenemase NDM-1 and the emergence of colistin-resistant A. baumannii in Algerian hospitals.

scholarly journals Biotyping, serotyping and ribotyping as epidemiological tools in the evaluation of Acinetobacter baumannii dissemination in hospital units, Sorocaba, São Paulo, Brazil

2000 ◽  
Vol 42 (5) ◽  
pp. 277-282 ◽  
Author(s):  
Célia R. GONÇALVES ◽  
Tania Mara I. VAZ ◽  
Eliane ARAUJO ◽  
Regina de Fátima BONI ◽  
Daniela LEITE ◽  
...  
Keyword(s):  
Acinetobacter Baumannii ◽  
Neonatal Intensive Care ◽  
Antimicrobial Agents ◽  
Hospital Setting ◽  
Sao Paulo ◽  
São Paulo ◽  
Clinical Specimens ◽  
Hospital Units ◽  
Almost All ◽  
Multiresistant Strains

Dissemination of Acinetobacter baumannii strains in different units of a hospital in Sorocaba, São Paulo, Brazil was evaluated over a period of two years. By using biotyping, serotyping and ribotyping, 27 distinct clones were differentiated among 76 strains isolated between 1993-94, from clinical specimens of hospitalized patients. Two clones, 2:O4:A (biotype:serotype:ribotype) and 2:O29:A accounted for the majority of strains widely disseminated in the units during 1993. The introduction in the hospital setting, of a new clone, 6:O13:B, at the end of 1993 and its predominance through 1994 is discussed. Among 15 strains isolated from neonates, 6 (40%) belonged to the same clone, 2:O4:A. Interestingly, this clone was almost all recovered in neonatal intensive care unit, nursery and in pediatric unit. All strains were susceptible to imipenem and polymyxcin B. Multiresistant strains (up to 12 antimicrobial agents) accounted for 66.7% and 84.8% of the strains isolated in 1993 and in 1994, respectively.

scholarly journals Increased colistin resistance of Acinetobacter species in intensive care unit-acquired infections in a tertiary care hospital

10.3823/815 ◽  
2017 ◽  
Vol 7 (3) ◽  
Author(s):  
Sanem Karadag Gecgel ◽  
Canan Demir
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Antimicrobial Resistance ◽  
Acinetobacter Baumannii ◽  
Tertiary Care ◽  
Care Hospital ◽  
Colistin Resistance ◽  
Acinetobacter Species ◽  
Gram Negative ◽  
Resistance Rates

Background: The aim of our study was to evaluate the antimicrobial resistance rates among pathogen microorganisms especially colistin resistant rates of Acinetobacter baumannii in intensive care unit (ICU)-acquired infections and to determine infection-specific correct treatment strategies. Methods: The data of adult and newborn infant patients diagnosed with ICU-acquired infection in a tertiary education and research hospital in Bursa in 2014 and 2016 were analyzed, retrospectively. Results: Acinetobacter baumannii was the most frequent pathogen of ICU-acquired infections in 2014 and 2016. There was a significant increase in colistin (CO) resistance rates in A. baumanii (0.0%-6.8%). A significant increase in CO, cefepime (FEP), ciprofloxacin (CIP) resistance rates was established in all gram negative bacteria (0.0%-7.9%, 50.0%-91.9%, 54.7%-74.6%), respectively. A significant increase in the rate of detection of A. baumanii as the pathogen microorganism in respiratory tract infection (RTI) was established (53.9% -79.5%). In addition, the average ventilator-associated pneumonia (VIP) infection rate also increased in 2016 compared to 2014 (VIP rate 2014: 7.12, 2016: 7.45, per 1000 ventilator days). A significant decrease in the rate of detection of all gram negative microorganisms in the surgical site infection (SSI), and a significant increase in the rate of detection of all gram positive microorganisms in the SSI was determined. Conclusion: Increased antimicrobial resistance, especially increased colistin resistance rates in ICU-acquired infections, necessitates the creation of new strategies in empirical therapy. Detection of antimicrobial resistance profiles of local and infectious pathogen microorganisms in ICUs is a good guide for correct antimicrobial management.

First Detection of Tobacco Mosaic Virus in Tobacco Fields in Northern Lebanon

2020 ◽  
Vol 20 ◽  
Author(s):  
Rami Obeid ◽  
Elias Wehbe ◽  
Mohamad Rima ◽  
Mohammad Kabara ◽  
Romeo Al Bersaoui ◽  
...  
Keyword(s):  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
Viral Genome ◽  
Virus Genome ◽  
Enzyme Linked Immunosorbent Assay ◽  
Virus Family ◽  
Crop Fields ◽  
Wide Range ◽  
Almost All ◽  
Das Elisa

Background: Tobacco mosaic virus (TMV) is the most known virus in the plant mosaic virus family and is able to infect a wide range of crops, in particularly tobacco, causing a production loss. Objectives: Herein, and for the first time in Lebanon, we investigated the presence of TMV infection in crops by analyzing 88 samples of tobacco, tomato, cucumber and pepper collected from different regions in North Lebanon. Methods: Double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA), revealed a potential TMV infection of four tobacco samples out of 88 crops samples collected. However, no tomato, cucumber and pepper samples were infected. The TMV+ tobacco samples were then extensively analyzed by RT-PCR to detect viral RNA using different primers covering all the viral genome. Results and Discussion: PCR results confirmed those of DAS-ELISA showing TMV infection of four tobacco samples collected from three crop fields of North Lebanon. In only one of four TMV+ samples, we were able to amplify almost all the regions of viral genome, suggesting possible mutations in the virus genome or an infection with a new, not yet identified, TMV strain. Conclusion: Our study is the first in Lebanon revealing TMV infection in crop fields, and highlighting the danger that may affect the future of agriculture.

INFLUENCE OF WEATHER ON TEMPORARY AND PERMANENT MIGRATION IN RURAL INDIA

2013 ◽  
Vol 04 (02) ◽  
pp. 1350007 ◽  
Author(s):  
K. S. KAVI KUMAR ◽  
BRINDA VISWANATHAN
Keyword(s):  
National Sample ◽  
Sample Survey ◽  
Urban Migration ◽  
Temporary Migration ◽  
Urban Migrants ◽  
Wide Range ◽  
Permanent Migration ◽  
Sample Survey Data ◽  
Almost All ◽  
Temporary Migrants

While a wide range of factors influence rural–rural and rural–urban migration in developing countries, there is significant interest in analyzing the role of agricultural distress and growing inter-regional differences in fueling such movement. This strand of research acquires importance in the context of climate change adaptation. In the Indian context, this analysis gets further complicated due to the significant presence of temporary migration. This paper analyzes how weather and its variability affects both temporary and permanent migration in India using National Sample Survey data for the year 2007–2008. The paper finds that almost all of the rural–urban migrants are permanent. Only temperature plays a role in permanent migration. In contrast, many temporary migrants are rural–rural and both temperature and rainfall explain temporary migration.

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