Phenotypic and genotypic characteristics of tetracycline resistant Acinetobacter baumannii isolates from nosocomial infections at Tehran hospitals

Document Type : Original Article

Authors

1 Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran

2 Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, University of Putra, Malaysia

3 Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran.Department of Microbiology, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran

4 Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran 2 Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, University of Putra, Malaysia

5 Psychosocial Injuries Research Center, Ilam University of Medical Sciences, Ilam, Ira

6 Department of Microbiology, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran

7 Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran

Abstract

Objective(s):To date, the most important genes responsible for tetracycline resistance among Acinetobacter baumannii isolates have been identified as tet A and tet B. This study was carried out to determine the rate of resistance to tetracycline and related antibiotics, and mechanisms of resistance.
 Materials and Methods: During the years 2010 and 2011, a total of 100 A. baumannii isolates were recovered from patients in different hospitals of Tehran, Iran. Antimicrobial susceptibility to tetracycline, minocycline, doxicycline and tigecycline was evaluated by E-test. Polymerase chain reaction (PCR) of the tet A and tet B genes was performed using specific primers, after which the isolates were subjected to Repetitive Extragenic Palindromic-PCR (PCR) to identify the major genotypes.
Results: Of all isolates, 89% were resistant to tetracycline (MIC50 = 32 μg/ml, MIC90 = 512 μg/ml). Minocycline with the resistant rate of 35% (MIC50 = 16 μg/ml, MIC90 =32 μg/ml) and doxicycline with the resistant rate of 25% (MIC50 = 16 μg/ml, MIC90= 32 μg/ml) have a good activity against A. baumannii isolates. All isolates were sensitive to tigecycline. Frequencies of tet B and tet A genes and coexistence of tet A and tet B among the isolates resistant to tetracycline, were 87.6%, 2.2% and 1.1%, respectively. Distribution of REP-types among A. baumannii isolates was types A (40%), B (30%), C (10%), D (5%) and E (5%).
Conclusion: It seems that tet A and tet B genes play an important role in the induction of resistance towards tetracyclines used in this study. It is suggested that further studies focus on other antimicrobial drugs and combinations in order to achieve a successful therapy against multi drug resistance (MDR) A. baumannii strains in Iran.
 

Keywords


1. Peleg AY, Seifert H, Paterson DL. Acinetobacter baumannii: emergence of a successful pathogen. Clin Microbiol Rev 2008; 21:538-82.
2. Hanlon GW. The emergence of multidrug resistant Acinetobacter species: a major concern in the hospital setting. Lett Appl Microbiol 2005; 41:375-378.
3. Asadollahi K, Alizadeh E, Akbari M, Taherikalani M, Niakan M, Maleki A,et al. The role of bla(OXA-like carbapenemase) and their insertion sequences (ISS) in the induction of resistance against carbapenem antibiotics among Acinetobacter baumannii isolates in Tehran hospitals. Roum Arch Microbiol Immunol 2011; 70: 153-158.
4. Asadollahi, K., Taherikalani M, Maleki A, Alizadeh E, Valadbaigi H, Soroush S,et al. Diversity of aminoglycoside modifying enzyme genes among multidrug resistant Acinetobacter baumannii genotypes isolated from nosocomial infections in Tehran hospitals and their association with class 1 integrons. Acta Microbiol Immunol Hung 2011; 58: 359-370.
5. Feizabadi MM, Fathollahzadeh B, Taherikalani M, Rasoolinejad M, Sadeghifard N, Aligholi M,et al. Antimicrobial susceptibility patterns and distribution of blaOXA genes among Acinetobacter spp. Isolated from patients at Tehran hospitals. Jpn J Infect Dis 2008; 61: 274-278.
6. Taherikalani M, Fatolahzadeh B, Emaneini M, Soroush S, Feizabadi MM. Distribution of different carbapenem resistant clones of Acinetobacter baumannii in Tehran hospitals. New Microbiol 2009; 32:265-271.
7. Soroush S, Haghi-Ashtiani MT, Taheri-Kalani M, Emaneini M, Aligholi M, Sadeghifard N, Pakzad I,et al. Antimicrobial resistance of nosocomial strain of Acinetobacter baumannii in Children's Medical Center of Tehran: a 6-year prospective study. Acta Med Iran 2010; 48: 178-184.
8. Akbari M,Niakan M, Taherikalani M, Feizabadi MM, Azadi NA, Soroush S,et al. Rapid identification of Iranian Acinetobacter baumannii strains by single PCR assay using BLA oxa-51 -like carbapenemase and evaluation of the antimicrobial resistance profiles of the isolates. Acta Microbiol Immunol Hung 2010; 57: 87-94.
9. Taherikalani M, emadi G, Geliani KN, Fatollahzadeh B, Soroush S, Feizabadi MM.Emergence of multi and pan-drug resistance Acinetobacter baumannii carrying blaOXA-type -carbapenemase genes among burn patients in Tehran, Iran. Saudi Med J 2008; 29:623-624.
10. Kalantari N, Taherikalani M, Parvaneh N and Mamishi S. Etiology and antimicrobial susceptibility of bacterial septic arthritis and osteomyelitis. Iran J Public Health 2007; 36: 27-32.
11. Haghi-Ashteiani M, Sadeghifard N, Abedini M, Soroush S, Taheri-Kalani M. Etiology and antibacterial resistance of bacterial urinary tract infections in children's medical center, Tehran, Iran. Acta Medica Iranica 2007; 45: 153-157.
 
12. Asadollahi P, Akbari M, Soroush S, Taherikalani M, Asadollahi K, Sayemiri K,et al. Antimicrobial resistance patterns and their encoding genes among Acinetobacter baumannii strains isolated from burned patients. Burns 2012; 38: 1198-203.
13. Akbari M, et al. Rapid identification of Iranian Acinetobacter baumannii strains by single PCR assay using blaOXA-51-like carbapenemase and evaluation of the antimicrobial resistance profiles of the isolates. Acta Microbiologica et Immunologica Hungarica 2010; 57: 431.
14. CLSI, Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically; approved standard, 8th ed. Clinical and Laboratory Standards Institute, Wayne: PA., 2009. CLSI document p. M7-A8.
15. Pajand O, Rezaee MA, Nahaei MR, Mahdian R, Aghazadeh M, Soroush MH, et al. Study of the carbapenem resistance mechanisms in clinical isolates of Acinetobacter baumannii: Comparison of burn and non-burn strains. Burns 2013; 39:1414-1419.
16. Srinivasan VB, Rajamohan G, Pancholi P, Stevenson K, Tadesse D, Patchanee P, et al. Genetic relatedness and molecular characterization of multidrug resistant Acinetobacter baumannii isolated in central Ohio, USA. Ann Clin Microbiol Antimicrob 2009; 8:21.
17. Vila J, Marcos MA, Jimenez de Anta MT. A comparative study of different PCR-based DNA fingerprinting techniques for typing of the Acinetobacter calcoaceticus-A. baumannii complex. J Med Microbiol 1996; 44:482-489.
18. Safari M, Saidijam M, Bahador A, Jafari R, Alikhani MY.High Prevalence of Multidrug Resistance and Metallo-beta-lactamase (MbetaL) producing Acinetobacter Baumannii Isolated from Patients in ICU Wards, Hamadan, Iran. J Res Health Sci 2013; 13:162-167.
19. Bahador A, Taheri M, Pourakbari B, Hashemizadeh Z, Rostami H, Mansoori N, et al. Emergence of rifampicin, tigecycline, and colistin-resistant Acinetobacter baumannii in Iran; spreading of MDR strains of novel International Clone variants. Microb Drug Resist 2013; 19:397-406.
20. Ruzin A, Keeney D, Bradford PA. AdeABC multidrug efflux pump is associated with decreased susceptibility to tigecycline in Acinetobacter calcoaceticus-Acinetobacter baumannii complex. J Antimicrob Chemother 2007; 59:1001-1004.
21. Seifert H, Stefanik D, Wisplinghoff H. Comparative in vitro activities of tigecycline and 11 other antimicrobial agents against 215 epidemiologically defined multidrug-resistant Acinetobacter baumannii isolates. J Antimicrob Chemother 2006; 58:1099-1100.
22. Mezzatesta ML, Trovato G, Gona F, Nicolosi VM, Nicolosi D, Carattoli A,et al. In vitro activity of tigecycline and comparators against carbapenem-susceptible and resistant Tetracycline resistant A. baumannii Maleki et al Iran J Basic Med Sci, Vol. 17, No.1, Jan 2014 26 Acinetobacter baumannii clinical isolates in Italy. Ann Clin Microbiol Antimicrob 2008; 7:4.
 
23. Navon-Venezia S, Leavitt A, Carmeli Y. High tigecycline resistance in multidrug-resistant Acinetobacter baumannii. J Antimicrob Chemother 2007; 59:772-774.
24. Salazar De Vegas EZ, Nievesm B, Ruiz M, Ruیz J, Vila J, Marیa A, et al. Molecular epidemiology and characterization of resistance mechanisms to various antimicrobial agents in Acinetobacter baumannii isolated in Merida, Venezuela. Med Sci Monit 2007; 13: 89-94.
25. Pei G, Mao Y, Sun Y In vitro activity of minocycline alone and in combination with cefoperazone-sulbactam against carbapenem-resistant Acinetobacter baumannii. Microb Drug Resist 2012; 18: 574-577.
26. Denys GA, Callister SM, Dowzicky MJ, Antimicrobial susceptibility among gram-negative isolates collected in the USA between 2005 and 2011 as part of the Tigecycline Evaluation and Surveillance Trial (T.E.S.T.). Ann Clin Microbiol Antimicrob 2013; 12:24.
27. Guardabassi L, Dijkshoorn L, Collard JM, Olsen JE, Dalsgaard A. Distribution and in-vitro transfer of tetracycline resistance determinants in clinical and aquatic Acinetobacter strains. J Med Microbiol 2000; 49:929-936.
28. Chopra I, Roberts M. Tetracycline antibiotics: mode of action, applications, molecular biology, and epidemiology of bacterial resistance. Microbiol Mol Biol Rev 2001; 65:232-260.
29. Ribera A, Ruiz J,Vila J. Presence of the Tet M determinant in a clinical isolate of Acinetobacter baumannii. Antimicrob Agents Chemother 2003; 47:2310-2312.
30. Mak JK, Kim MJ, Pham J, Tapsall J, White PA. Antibiotic resistance determinants in nosocomial strains of multidrug-resistant Acinetobacter baumannii. J Antimicrob Chemother 2009; 63:47-54.
31. Mammina C, Palma DM, Bonura C, Aleo A, Fasciana T, Sodano C,et al. Epidemiology and clonality of carbapenem-resistant Acinetobacter baumannii from an intensive care unit in Palermo, Italy. BMC Res Notes 2012; 5:65.
32. Park S, Kim HS, Lee KM, Yoo JS, Yoo JI, Lee YS,et al., Molecular and epidemiological characterization of carbapenem-resistant Acinetobacter baumannii in non-tertiary Korean hospitals. Yonsei Med J 2013;54: 177-182.
33. Andriamanantena TS, Ratsima E, Rakotonirina HC, Randrianirina F, Ramparany L, Carod J,et al. Dissemination of multidrug resistant Acinetobacter baumannii in various hospitals of Antananarivo Madagascar. Ann Clin Microbiol Antimicrob 2010; 9:17.