Characterization of Escherichia coli Phylogenetic Groups Associated with Extraintestinal Infections in South Indian Population

Chakraborty, Arindham and Saralaya, Vishwas and Adhikari, Prabha and Shenoy, Shalini and Baliga, Shrikala and Hegde, Ashwini (2015) Characterization of Escherichia coli Phylogenetic Groups Associated with Extraintestinal Infections in South Indian Population. Annals of Medical and Health Sciences Research, 5 (4). pp. 241-246. ISSN 2141-9248

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Background: Escherichia coli strains mainly fall into four phylogenetic groups (A, B1, B2, and D) and that virulent extra‑intestinal strains mainly belong to groups B2 and D. Aim: The aim was to determine the association between phylogenetic groups of E. coli causing extraintestinal infections (ExPEC) regarding the site of infection, expression of virulence factors, antimicrobial resistance patterns, and clinical outcome. This descriptive study was carried out in a multi‑specialty Tertiary Care Hospital. Materials and Methods: A total of 300 E. coli causing ExPEC were studied. Triplex polymerase chain reaction was used to classify the phylogenetic groups; hemolysin production was assessed on sheep blood agar and biofilm production in a microtiter plate assay. Production of extended spectrum of beta‑lactamase (ESBLs) was detected by combination disk method; AmpC was detected by AmpC disk test, Carbapenemase production was detected by modified Hodge test and metallo‑β‑lactamase by metallo‑beta‑lactamases (MBL) E‑test. Results: Of 300 isolates, 61/300 (20 %) belonged to phylogroup A, 27/300 (9%) to phylogroup B1, 104/300 (35%) were B2 and 108/300 (36%) belonged to group D, respectively. Phylogroups B2 and D were the most predominant groups in urinary tract infection and sepsis. Prognoses were better in infections with group A and B1 isolates, and relapses and death were common in infections with B2 and D. Expression of biofilm was greatest in B1 and hemolysin in group B2. Group A and B1 showed higher resistance to ciprofloxacin and were most frequent β‑lactamase (ESBL, AmpC, Carbapenemase and MBL) producers. Conclusions: Phylogenetic group B2 and D were predominant in ExPEC and exhibited least antimicrobial resistance among the groups. Resistance to multiple antibiotics was most prevalent in group A and B1. Regular monitoring of antimicrobial susceptibility in commensal strains is essential as they might transfer the property of antimicrobial resistance to pathogenic strains.

Item Type: Article
Uncontrolled Keywords: Drug resistance, Escherichia coli, Extraintestinal infections, Polymerase chain reaction, Phylogenetic group, Virulence
Subjects: Medicine > KMC Mangalore > Microbiology
Medicine > KMC Mangalore > Medicine
Depositing User: KMCMLR User
Date Deposited: 10 Jul 2015 06:18
Last Modified: 10 Jul 2015 06:18

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