1
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Phenotypic and genotypic characterization of clinical carbapenem-resistant Enterobacteriaceae isolates from Sokoto, northwest Nigeria

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Emergence and spread of carbapenemase-producing Enterobacteriaceae (CPE) are two of the major problems currently threatening global public health. In Nigeria, interest in CPE is recent. In Sokoto, northwest Nigeria, there are no data on the prevalence and mechanism underlying carbapenem resistance. In this study, we aimed to investigate the presence of clinical carbapenems-resistant Enterobacteriaceae isolates in two leading hospitals in Sokoto, northwest Nigeria. A total of 292 non-duplicate Enterobacteriaceae isolated from clinical specimens processed in the diagnostic laboratories of two hospitals between January and June 2019 were collected. Of these, 129 (44.2 %) and 19 (6.5%) were resistant to third-generation cephalosporin and carbapenems, respectively. RT-PCR revealed that 10 (7.8%), 19 (14.7%) and 46 (35.7%) of the third-generation cephalosporin-resistant isolates harboured bla SHV, bla TEM and bla CTX-M genes, respectively. The modified Carba NP test result showed that only 7 (36.8 %) of the 19 carbapenem-resistant isolates were carbapenemase producing; among them, bla NDM-5 and bla OXA-181 genes were identified in five and two isolates, respectively. However, none of the carbapenemase genes investigated, including bla VIM, bla KPC and bla IMP, was detected in the remaining carbapenem-resistant isolates, suggesting a non-enzymatic mechanism. This study reports for the first time, the emergence of CPE in Sokoto state and the detection of NDM-producing Citrobacter freundii in Nigeria. The observed CPE in this study is a concern in a country where alternative antibiotics are rarely available.

          Related collections

          Most cited references35

          • Record: found
          • Abstract: found
          • Article: not found

          Carbapenemases: the versatile beta-lactamases.

          Carbapenemases are beta-lactamases with versatile hydrolytic capacities. They have the ability to hydrolyze penicillins, cephalosporins, monobactams, and carbapenems. Bacteria producing these beta-lactamases may cause serious infections in which the carbapenemase activity renders many beta-lactams ineffective. Carbapenemases are members of the molecular class A, B, and D beta-lactamases. Class A and D enzymes have a serine-based hydrolytic mechanism, while class B enzymes are metallo-beta-lactamases that contain zinc in the active site. The class A carbapenemase group includes members of the SME, IMI, NMC, GES, and KPC families. Of these, the KPC carbapenemases are the most prevalent, found mostly on plasmids in Klebsiella pneumoniae. The class D carbapenemases consist of OXA-type beta-lactamases frequently detected in Acinetobacter baumannii. The metallo-beta-lactamases belong to the IMP, VIM, SPM, GIM, and SIM families and have been detected primarily in Pseudomonas aeruginosa; however, there are increasing numbers of reports worldwide of this group of beta-lactamases in the Enterobacteriaceae. This review updates the characteristics, epidemiology, and detection of the carbapenemases found in pathogenic bacteria.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Ongoing revolution in bacteriology: routine identification of bacteria by matrix-assisted laser desorption ionization time-of-flight mass spectrometry.

            Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry accurately identifies both selected bacteria and bacteria in select clinical situations. It has not been evaluated for routine use in the clinic. We prospectively analyzed routine MALDI-TOF mass spectrometry identification in parallel with conventional phenotypic identification of bacteria regardless of phylum or source of isolation. Discrepancies were resolved by 16S ribosomal RNA and rpoB gene sequence-based molecular identification. Colonies (4 spots per isolate directly deposited on the MALDI-TOF plate) were analyzed using an Autoflex II Bruker Daltonik mass spectrometer. Peptidic spectra were compared with the Bruker BioTyper database, version 2.0, and the identification score was noted. Delays and costs of identification were measured. Of 1660 bacterial isolates analyzed, 95.4% were correctly identified by MALDI-TOF mass spectrometry; 84.1% were identified at the species level, and 11.3% were identified at the genus level. In most cases, absence of identification (2.8% of isolates) and erroneous identification (1.7% of isolates) were due to improper database entries. Accurate MALDI-TOF mass spectrometry identification was significantly correlated with having 10 reference spectra in the database (P=.01). The mean time required for MALDI-TOF mass spectrometry identification of 1 isolate was 6 minutes for an estimated 22%-32% cost of current methods of identification. MALDI-TOF mass spectrometry is a cost-effective, accurate method for routine identification of bacterial isolates in or =10 reference spectra per bacterial species and a 1.9 identification score (Brucker system). It may replace Gram staining and biochemical identification in the near future.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Past and Present Perspectives on β-Lactamases

              Karen Bush (2018)
              β-Lactamases, the major resistance determinant for β-lactam antibiotics in Gram-negative bacteria, are ancient enzymes whose origins can be traced back millions of years. These well-studied enzymes, currently numbering almost 2800 unique proteins, initially emerged from environmental sources, most likely to protect a producing bacterium from attack by naturally-occurring β-lactams. Their ancestors were presumably penicillin-binding proteins that share sequence homology with β-lactamases possessing an active site serine. Metallo-β-lactamases also exist, with one, or two, catalytically functional zinc ions. Although penicillinases in Gram-positive bacteria were reported shortly after penicillin was introduced clinically, transmissible β-lactamases that could hydrolyze recently-approved cephalosporins, monobactams and carbapenems later became important in Gram-negative pathogens. Nomenclature is based on one of two major systems. Originally, functional classifications were used, based on substrate and inhibitor profiles. A later scheme classifies β-lactamases according to amino acid sequences, resulting in class A, B, C and D enzymes. A more recent nomenclature combines the molecular and biochemical classifications into 17 functional groups that describe most β-lactamases. Some of the most problematic enzymes in the clinical community include extended-spectrum β-lactamases (ESBLs) and the serine and metallo-carbapenemases, all of which are at least partially addressed with new β-lactamase inhibitor combinations. New enzyme variants continue to be described, partly because of the ease of obtaining sequence data from whole genome sequencing studies. Often these new enzymes are devoid of any phenotypic descriptions, making it more difficult for clinicians and antibiotic researchers to address new challenges that may be posed by unusual β-lactamases.
                Bookmark

                Author and article information

                Contributors
                Journal
                New Microbes New Infect
                New Microbes New Infect
                New Microbes and New Infections
                Elsevier
                2052-2975
                01 August 2020
                September 2020
                01 August 2020
                : 37
                : 100727
                Affiliations
                [1) ]Department of Pharmaceutics and Pharmaceutical Microbiology, Usmanu Danfodiyo University Sokoto, Nigeria
                [2) ]Department of Pharmaceutics and Pharmaceutical Microbiology, Ahmadu Bello University, Zaria, Nigeria
                [3) ]Aix-Marseille Université, IRD, APHM, MEPHI, IHU-Mediterranée Infection, Marseille, France
                [4) ]Department of Medical Microbiology, College of Health Sciences, Usmanu Danfodiyo University, Sokoto, Nigeria
                [5) ]Université de Sétif 1, Laboratoire de Microbiologie (CHU de Sétif), Sétif, Algeria
                [6) ]IHU-Mediterranée Infection, Marseille, France
                Author notes
                [] Corresponding author: S.M. Diene, Aix-Marseille Université, IRD, APHM, MEPHI, IHU-Méditerranée Infection, 19–21 boulevard Jean Moulin, CEDEX 05, 13385, Marseille, France. seydina.diene@ 123456univ-amu.fr
                Article
                S2052-2975(20)30079-2 100727
                10.1016/j.nmni.2020.100727
                7479348
                32939286
                3d80e3b8-2626-4f08-b185-e50a94b7d185
                © 2020 The Authors

                This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

                History
                : 6 May 2020
                : 15 June 2020
                : 30 June 2020
                Categories
                Original Article

                blandm-5,blaoxa-181,carbapenem resistance,carbapenemase genes,nigeria

                Comments

                Comment on this article