title: Characterization of cephalosporin-resistant clinical Enterobacteriaceae for CTX-M ESBLs in Bahrain.
abstract: OBJECTIVE
  To detect the presence of specific CTX-M class of extended spectyum β-lactamases (ESBLs) in a collection of cephalosporin-resistant Enterobacteriaceae isolates from Bahrain.
  
  
  METHODS
  A subset of 80 cephalosporin-resistant Enterobacteriaceae collected from Salmaniya Medical Complex, Bahrain, were characterized further for the presence of specific genogroups of CTX-M β-lactamases by multiplex- and monoplex- PCRs. The primers used for the multiplex and monoplex PCRs were of genogroups- 1, 2, 8, 9 and 25. Sequencing of the representative isolates was performed to find the circulating CTX-M-types.
  
  
  RESULTS
  A total of 93.8% (75/80) isolates showed the amplicons corresponding to any of the genogroups (1, 2, 8, 9, 25) and the remaining 6.2% isolates turned out negative in multiplex PCR. Some of the isolates demonstrated multiple bands corresponding to the sizes of different genogroups. Further confirmation with respective monoplex PCR on these 75 isolates demonstrated that 93.3% (70/75) harbored CTX-M genogroup-1 and 6.7% (5/75) harbored genogroup-9. We did not find the presence of genogroups 2, 8, and 25 in these isolates by monoplex PCR. Sequencing results of genogroup-1 isolates demonstrated the presence of CTX-M-15-like ESBL, however, discrepant results were noticed in genogroup-9 isolates, sequencing showed them as CTX-M-55-like ESBL.
  
  
  CONCLUSIONS
  This is the first report from Bahrain characterizing the CTX-M genogroups of ESBLs and reporting the emergence of blaCTX-M-55-like gene in this region.
authors.affiliation: College of Medicine & Medical Sciences, Arabian Gulf University, Manama, Kingdom of Bahrain; King Hamad University Hospital, Busaiteen, Kingdom of Bahrain; Section of Antimicrobial Agents & Drug Resistance Research and Molecular Biology, Department of Medical Microbiology, Jawaharlal Nehru Medical College & Hospital, Aligarh Muslim University, Aligarh-202002, Uttar Pradesh, India. Electronic address: shahidsahar@yahoo.co.in.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Shahid
authors.affiliation: College of Medicine & Medical Sciences, Arabian Gulf University, Manama, Kingdom of Bahrain.
authors.forename: Ali
authors.initials: A
authors.lastname: Al-Mahmeed
authors.affiliation: College of Medicine & Medical Sciences, Arabian Gulf University, Manama, Kingdom of Bahrain.
authors.forename: Mariam Mumtaz
authors.initials: MM
authors.lastname: Murtadha
authors.affiliation: College of Medicine & Medical Sciences, Arabian Gulf University, Manama, Kingdom of Bahrain.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Qareeballa
authors.affiliation: College of Medicine & Medical Sciences, Arabian Gulf University, Manama, Kingdom of Bahrain.
authors.forename: Muhallab Abdulrahman
authors.initials: MA
authors.lastname: Eltahir
authors.affiliation: College of Medicine & Medical Sciences, Arabian Gulf University, Manama, Kingdom of Bahrain.
authors.forename: Khaled Saeed
authors.initials: KS
authors.lastname: Tabbara
authors.affiliation: College of Medicine & Medical Sciences, Arabian Gulf University, Manama, Kingdom of Bahrain.
authors.forename: Abdulrahman Yusuf
authors.initials: AY
authors.lastname: Ismaeel
authors.affiliation: College of Medicine & Medical Sciences, Arabian Gulf University, Manama, Kingdom of Bahrain.
authors.forename: Fazal Karim
authors.initials: FK
authors.lastname: Dar
authors.affiliation: College of Medicine & Medical Sciences, Arabian Gulf University, Manama, Kingdom of Bahrain.
authors.forename: Hayder Ahmed
authors.initials: HA
authors.lastname: Giha
authors.affiliation: College of Medicine & Medical Sciences, Arabian Gulf University, Manama, Kingdom of Bahrain; Microbiology Section, Salmaniya Medical Complex, Manama, Kingdom of Bahrain.
authors.forename: Khalid Mubarak
authors.initials: KM
authors.lastname: Bindayna
keywords: Bahrain; CTX-M-15; CTX-M-55; Extended-spectrum beta-lactamases; class A ESBLs