title: Molecular evaluations of extended spectrum β-lactamase producing strains of Serratia isolated from blood samples of the patients in Namazi Hospital, Shiraz, Southern Iran.
abstract: OBJECTIVE
  Nowadays, the presence of extended-spectrum β-lactamases (ESBLs) producing strains in Serratia genus causes the emergence of resistance to many antibiotics. So, the lack of proper diagnosis of ESBLs strains can lead to failure in the treatment. The objective of the present study was to investigate ESBLs production in Serratia strains isolated from the clinical blood samples in Shiraz, Iran.
  
  
  METHODS
  In this study, 39 Serratia strains isolated from the patients referred to Namazi Hospital, during a 2 year period were tested. The antimicrobial resistance of the isolates to 21 antibiotics was evaluated using Kirby-Bauer disk diffusion method. Combination disk method was used to determine the ESBL phenotype among the isolates. PCR was performed to investigate the presence of ESBL genes of SHV, OXA and TEM types.
  
  
  RESULTS
  The lowest antibiotic resistance rates belonged to meropenem (7.69%) and imipenem (5.12%). Overall, positive ESBL phenotype was identified in 69% (n = 27) of the isolates, 70.37% (n = 19) for S. marcescens and 29.62% (n = 8) for S. liquefaciens. Results obtained by PCR showed that only 20.51% carried OXA gene and 15.38% carried SHV-1 gene. TEM gene was detected in none of the isolates.
  
  
  CONCLUSIONS
  This study showed a high prevalence of the emerging ESBL producing strains among clinical isolates of Serratia that could lead to an increase in antibiotic resistance. However, ESBLs genes other than those tested here may be more responsible for the emergence of ESBL phenotype among Serratia clinical isolates in our region.
authors.affiliation: Department of Microbiology, Science and Research Branch, Islamic Azad University, Fars, Iran.
authors.forename: Neda
authors.initials: N
authors.lastname: Mostatabi
authors.affiliation: Clinical Microbiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Shohreh
authors.initials: S
authors.lastname: Farshad
authors.affiliation: Molecular Biology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Ranjbar
keywords: Extended-spectrum β-lactamases; OXA; SHV; Serratia; TEM
references.citation: Clin Infect Dis. 2004 Jul 1;39(1):31-7
references.pmid: 15206050
references.citation: J Microbiol Immunol Infect. 1998 Sep;31(3):171-9
references.pmid: 10496154
references.citation: J Clin Microbiol. 2004 Dec;42(12):5917-20
references.pmid: 15583340
references.citation: Jpn J Infect Dis. 2006 Jun;59(3):147-52
references.pmid: 16785693
references.citation: J Med Microbiol. 2011 Jan;60(Pt 1):84-90
references.pmid: 20930052
references.citation: Antimicrob Agents Chemother. 1989 Aug;33(8):1131-6
references.pmid: 2679367
references.citation: Antimicrob Agents Chemother. 1995 Jun;39(6):1211-33
references.pmid: 7574506
references.citation: Diagn Microbiol Infect Dis. 2003 Apr;45(4):221-4
references.pmid: 12729989
references.citation: Clin Microbiol Rev. 2005 Oct;18(4):657-86
references.pmid: 16223952
references.citation: Environ Microbiol. 2009 Jun;11(6):1506-17
references.pmid: 19226301
references.citation: Clin Microbiol Infect. 2001 Nov;7(11):597-608
references.pmid: 11737084
references.citation: Antimicrob Agents Chemother. 2008 Sep;52(9):3244-52
references.pmid: 18591273
references.citation: Proc Natl Acad Sci U S A. 1987 Nov;84(21):7378-82
references.pmid: 2823258
references.citation: J Antimicrob Chemother. 1995 Jan;35(1):7-22
references.pmid: 7768784
references.citation: Diagn Microbiol Infect Dis. 2004 Jun;49(2):125-9
references.pmid: 15183862
references.citation: J Clin Microbiol. 2001 Jun;39(6):2206-12
references.pmid: 11376058
references.citation: Clin Microbiol Rev. 2001 Oct;14(4):933-51, table of contents
references.pmid: 11585791
references.citation: Iran J Microbiol. 2013 Jun;5(2):108-12
references.pmid: 23825726
references.citation: Foodborne Pathog Dis. 2010 Jan;7(1):91-5
references.pmid: 19785534
references.citation: Clin Infect Dis. 2001 Apr 1;32(7):1085-9
references.pmid: 11264037