Prevalence of PER and VEB Type Extended Spectrum Betalactamases among Multidrug Resistant Acinetobacter baumannii Isolates in North-West of Iran

Document Type : Original Article


1 Drug Applied Research Center, Tabriz University of Medical Science, Tabriz, Iran

2 Biotechnology Research Center, Tabriz University of Medical Science, Tabriz, Iran

3 Microbiology Department, Hamadan University of Medical Science, Hamadan, Iran

4 Istanbul University, Faculty of Sciences, Molecular Biology and Genetic, Istanbul, Turkey

5 Microbiology Department, Qazvin University of Medical Science, Qazvin, Iran

6 Paramedical Faculty, Kermanshah University of Medical Sciences, Kermanshah, Iran



Objective(s): Drug resistant Acinetobacter baumannii have emerged as a major problem in many hospitals and intensive care units. Various types of extended spectrum beta-lactamases (ESBLs) are responsible for resistance to beta-
lactam antibiotics in different parts of the world. The objective of this study was to determine the prevalence of integron class1 (INT 1) and ESBL types PER-1, PER-2 and VEB-1 among A. baumannii strains isolated from Tabriz, North-West of Iran.
Material and Methods:
A total of 100 A. baumannii isolates collected from different clinical samples were included in the study. Antimicrobial susceptibility profiles were determined using the Kirby Bauer disk diffusion method. Production of ESBL was investigated by testing resistance against ceftazidime, cefotaxime, ceftriaxone and verified by Double Disk Synergy Test. DNA was extracted from the isolates and the frequency of INT 1 and ESBL types PER-1, PER-2 and VEB-1 were determined by PCR using specific primers.
Among 100 A. baumannii isolates screened, 80 isolates were multidrug-resistant and 70 isolates were positive for ESBL production. PCR screening revealed that 74 % of the isolates contained class 1 integron, 51% were positive for PER-1 gene, 10% positive for VEB1 whereas none of the isolates were positive for PER2 type gene.
This is the first report of ESBL types VEB and PER in A. baumannii from North West of Iran. The results of this study demonstrated high prevalence of PER-1 and VEB-1 type ESBLs among A. baumannii isolates in the study region and reminded the necessity of appropriate infection control strategy to prevent further spread of infection by these organisms.



    1. Murray PR, Baron EJ, Pfaller MA, Tenover FC. Yolken RH. Manual of Clinical Microbiology.7th ed.Washington,D.C: ASM Press;1999.p. 517- 525.
    2.  Huang LY, Chen TL, Lu PL, Tsai CA, Cho WL, Chang FY, et al. Dissemination of multidrug-resistant, class 1 integron-carrying Acinetobacter baumannii isolates in Taiwan. Clin Microbiol Infect 2008; 14:1010–1019.
    3.  Nowak-Zaleska A, Krawczyk B, Kotłowski R, Mikucka A, Gospodarek E. Amplification of a single-locus variable-number direct repeats with restriction fragment length polymorphism (DR-PCR/RFLP) for genetic typing of Acinetobacter baumannii strains. Pol J Microbiol 2008; 57:11-17.
    4. Peleg AY, Seifert H, Paterson DL. Successful Pathogen Acinetobacter baumannii: Emergence of a10.1128/CMR.00058-07. Clin Microbiol Rev2008; 21:538.
    5. Marais E, G de Jong, Ferraz V, Maloba B, Duse AG.Interhospital transfer of pan-resistant Acinetobacter strains in Johannesburg,South Africa. Am J Infect Control 2004; 32:278–281.
    6. Merkier AK, Catalano M, Ramírez MS, Quiroga C, Orman B, Ratier L, et al.  Polyclonal spread of blaOXA-23 and blaOXA-58 in Acinetobacter baumannii isolates from Argentina. J Infect Dev Ctries 2008; 2:235-240.
    7. Coelho J, Woodford N, Afzal-Shah M, Livermore D. Occurrence of OXA-58-Like Carbapenemases in Acinetobacter spp. collected over 10 years in three continents. Antimicrob Agents Chemother 2006; 50:756-758.
    8. Dijkshoorn L, Nemec A, Seifert H. An increasing threat in hospitals: multidrug-resistant Acinetobacter baumannii. Nat Rev Microbiol 2007; 5:939-951.
    9. Bradford PA. Extended-spectrum beta-lactamases in the 21st century: characterization, epidemiology, and detection of this important resistance threat. Clin Microbiol Rev 2001; 14:933-951.
    10. 10.  Jacoby GA, Munoz-Price LS. Mechanisms of disease the new ß-Lactamases. N Engl J Med 2005; 352:380-3891.

    11. Gniadkowski M. Evolution and epidemiology of extended-spectrum b-lactamases (ESBLs) and ESBL-producing microorganisms. Clin Microbiol Infect 2001; 7:597–608.

    12. Bush k. New beta-lactamases in gram negative bacteria: diversity and impact on the selection of antimicrobial therapy. Clin Infect Dis 2001; 32:1085-1089.

    13. Stürenburg E, Mack D. Extended-spectrum beta-lactamases: implications for the clinical microbiology laboratory, therapy, and infection control. J Infect  2003; 47:273-295.

    1. 14.  Rasheed JK, Jay C, Metchock B, Berkowitz F, Weigel L, Crellin J, et al. Evolution of extended-spectrum b-lactam resistance (SHV-8) in a strain of Escherichia coli during multiple episodes of bacteremia. Antimicrob Agents Chemother 1997; 41:647- 653.

    15. Ribera A, Vila J, Fernández-Cuenca F, Martínez-Martínez L, Pascual A, Beceiro A, et al. Spanish Group for Nosocomial Infection (GEIH). Type 1 integrons in epidemiologically unrelated acinetobacter baumannii isolates collected at spanish hospitals, American Society for Microbiology. Antimicrob Agents
    Chemother 2004; 48:364-365.

    16. Yousefi S, Farajnia S, Nahaei MR, Akhi MT, Ghotaslou R, Soroush MH, et al. Detection of metallo-β-lactamase-encoding genes among clinical isolates of Pseudomonas aeruginosa in northwest of Iran. Diagn  Microbiol Infect  Dis  2010; 68:322-5.

    17. García-Garmendia JL, Carlos OL, José GM , Francisco-Javier J-J , Carmen P-P, Ana EBA, et al. Risk Factors for Acinetobacter baumannii Nosocomial Bacteremia in Critically Ill Patients :A Cohort Study.Clin Infect Dis 2001;33: 939-946.

    18. Perez F, Hujer AM, Hujer KM, Decker BK, Rather PhN, Bonomo RA. Global challenge of multidrug-resistant Acinetobacter baumannii. Antimicrob Agents Chemother 2007; 51:3471–3484.

    19. Vahaboglu H, Oztürk R, Aygün G, Coşkunkan F, Yaman A, Kaygusuz A, et al. Wide- spread detection of PER-1-type extended-spectrum beta-lactamases among nosocomial Acinetobacter and Pseudomonas aeruginosa isolates in Turkey: A nationwide multi-center study. Antimicrob Agents Chemother 1997; 41:2265–2269.

    20. Yong D, Shin JH, Kim S, Lim Y, Yum JH, Lee K, et al. High prevalence of PER-1 extended-spectrum beta-lactamase-producing Acinetobacter spp. in Korea. Antimicrob Agents Chemother 2003; 47:1749–1751.

    21. Poirel L, Menuteau O, Agoli N, Cattoen C, Nordmann P. Outbreak of extended-spectrum beta-lactamase VEB-1-producing isolates of acinetobacter baumannii in a French Hospital. J Clin Microbiol 2003; 41:3542–3547.

    22. Naas T, Bogaerts P, Bauraing C, Degheldre Y, Glupczynski Y, Nordmann P. Emergence of PER and VEB extended-spectrum beta-lactamases in Acinetobacter baumannii in Belgium. J Antimicrob Chemother 2006; 58:178-82.

    23. Pasterán F, Rapoport M, Petroni A, Faccone D, Corso A, Galas M, et al. Emergence of PER-2 and VEB-1a in Acinetobacter baumannii Strains in the Americas. Antimicrob Agents Chemother 2006; 50:3222-3224.

    24. Poirel L, Corvec S, Rapoport M, Mugnier P, Petroni A, Pasteran F, et al.  Identification of the novel narrow-spectrum ß-lactamase SCO-1 in Acinetobacter spp. from Argentina. Antimicrob Agents Chemother 2007; 51:2179-2184.

    25. Gombac F, Riccio ML, Rossolini GM, Lagatolla C, Tonin E, Monti-Bragadin C, et al. Molecular characterization of integrons in epidemiologically unrelated clinical isolates of acinetobacter baumannii from Italian hospitals reveals a limited diversity of gene cassette arrays.Antimicrob Agents Chemother 2002; 46:3665–3668.

    26. Fournier PE, Richet H. The epidemiology and control of Acinetobacter baumannii in health care facilities. Clin Infect Dis 2006; 42:692-699.