Prevalence of Class 1, 2, and 3 Integrons and Biofilm Formation in Pseudomonas aeruginosa and Acinetobacter baumannii among ICU and non-ICU Patients

Authors
Mina Aryanezhad 1
Afsaneh Karmostaji 2
Mohammad Reza Shakibaie 3
Afsaneh Karmostaji 2
Samane Shakibaie 4
1 Department of Microbiology and Virology, Afzalipuor School of Medicine, Kerman university of Medical Sciences, Kerman, Iran.
2 Infectious and Tropical Diseases Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
3 Department of Microbiology and Virology, Kerman University of Medical Sciences, Kerman, Iran
4 Students Research Committee, Kerman university of Medical Sciences, Kerman, Iran.
Abstract
Background: Infections caused by Pseudomonas aeruginosa or Acinetobacter baumannii are of greatest concern for hospitalized patients, particularly those in intensive care units (ICUs). The aims of this study were to investigate the prevalence of integrons and biofilm formation among P. aeruginosa and A. baumannii isolates collected from ICU and non-ICU inpatients.
Materials and Methods: A total of 90 P. aeruginosa and 90 A. baumannii isolates were recovered from patients admitted into diverse units of Shahid Mohammadi hospital in Bandar Abbas from January to December 2014. Bacterial identification was carried out by phenotypic methods and PCR. Antibiotic susceptibility was measured by disk diffusion assay. The presence of Class 1, 2, and 3 integrons were evaluated by multiplex-PCR. Biofilm quantification was done by microtiter method.
Results: The highest number of isolates (48%) were recovered from ICU patients. 81% of P. aeruginosa isolateswere sensitive to piperacillin/tazobactam and ticarcillin, while 60% were resistant to third generation of cephalosporins. In case of A. baumannii, all the isolates were sensitive to colistin, but 98% were resistant to other antibiotics (p≤0.05). Susceptibility to ceftazidime, ticarcillin, imipenem, and piperacillin/tazobactam were higher among isolates obtained from non-ICU patients. Class 1 integron was detected in 13.3% of the P. aeruginosa and 40% of the A. baumannii isolates, while Class 2 integron was harbored by 7 and 6.6% of the isolates, respectively. Furthermore, 23% of the A. baumannii and 12% of the P. aeruginosa isolates showed strong biofilm activity.
Conclusion: Class 1 integron-positive isolates were resistant to three classes of antibiotics and predominantly observed in specimens collected from ICU patients showing strong biofilm.
Keywords
ICU
Antibiotic resistance
integrons
Multiplex-PCR
  1. Potron A, Poirel L, Nordmann P. Emerging broad-spectrum resistance in Pseudomonas aeruginosa and Acinetobacter baumannii: mechanisms and epidemiology. Int J Antimicrob Agents. 2015; 45(6): 568–85.

  2. Karlowsky JA, Draghi DC, Jones ME, Thornsberry C, Friedland IR, Sahm DF. Surveillance for antimicrobial susceptibility among clinical isolates of Pseudomonas aeruginosa and Acinetobacter baumannii from hospitalized patients in the United States, 1998 to 2001. Antimicrob Agents Chemother. 2003; 47(5): 1681-8.

  3. Gaynes R, Edwards JR. National nosocomial infections surveillance system. Overview of nosocomial infections caused by gram-negative bacilli. Clin Infect Dis. 2005; 41(6): 848-54.

  4. Navon-Venezia S, Ben-Ami R, Carmeli Y. Update on Pseudomonas aeruginosa and Acinetobacter baumannii infections in the healthcare setting. Curr Opin Infect Dis. 2005; 18(4): 306–13.

  5. Bonnin RA, Nordmann P, Poirel L. Screening and deciphering antibiotic resistance in Acinetobacter baumannii: a state of the art. Exp Rev Anti Infect Ther. 2013; 11(6): 571-83.

  6. Falagas ME, Kopterides P. Risk factors for the isolation of multi-drug-resistant Acinetobacter baumannii and Pseudomonas aeruginosa: a systematic review of the literature. J Hosp Infect. 2006; 64(1): 7–15.

  7. Mazel D. Integrons: agents of bacterial evolution. Nat Rev Microbiol. 2006; 4(8): 608–20.

  8. Sung JY, Koo SH, Kim S, Kwon KC. Epidemiological characterizations of Class 1 integrons from multidrug-resistant Acinetobacter isolates in Daejeon, Korea. Ann Lab Med. 2014; 34(4): 293-9.

  9. Goudarzi SM, Eftekhar F. Multidrug resistance and integron carriage in clinical isolates of Pseudomonas aeruginosa in Tehran, Iran. Turk J Med Sci. 2015; 45:789-93.

  10. Diaz-Mejia JJ, Amabile-Cuevas CF, Rosas I, Souza V. An analysis of the evolutionary relationships of integron integrases, with emphasis on the prevalence of Class 1 integrons in Escherichia coli isolates from clinical and environmental origins. Microbiol. 2008; 154:94–102.

  11. Rowe-Magnus DA, Mazel D. The role of integrons in antibiotic resistance gene capture. Int J Med Microbiol. 2009; 292(2): 115–25.

  12. Rodriguez-Minguela CM, Apajalahti JH, Chai B, Cole JR, Tiedje JM. Worldwide prevalence of Class 2 integrases outside the clinical setting is associated with human impact. Appl Environ Microbiol. 2009; 75(15): 5100–5110.

  13. Correia M, Boavida F, Grosso F, Salgado MJ, Lito LM, Cristino JM, et al. Molecular characterization of a new Class 3 integron in Klebsiella pneumoniae. Antimicrob Agents Chemother. 2003; 47(9): 2838–43.

  14. Cicek A, Saral A, Duzgun A, Cizmeci T, Kayman T, OzlemBalci P, et al. Screening of Class 1 and Class 2 integrons in clinical isolates of Pseudomonas aeruginosa collected from seven hospitals in Turkey: A multicenter study. OJMM.  2013; 3(4): 227-33.

  15. Partridge SR, Tsafnat G, Coiera E, Iredel JR. Gene cassettes and cassette arrays in mobile resistance integrons. FEMS Microbiol Rev. 2009; 33(4): 757–84.

  16. Rajabnia R, Asgharpour F, FerdosiShahandashti E, Khalilian M, Norkhomami S, Shafii M. Class 1 integron in Pseudomonas aeruginosa isolates from different places and devices of ICU in Babol, Iran. Jundishapur J Microbiol. 2013; 6(2): 138-143.

  17. Japoni-Nejad A, Farshad S, van Belkum A, Ghaznavi-Rad E. Novel cassette array in a Class 1 integron in clinical isolates of Acinetobacter baumannii from central Iran. Int J Med Microbiol. 2013; 303(8): 645-50.

  18. Clinical and Laboratory Standards Institute. Performance standards for antimicrobial susceptibility testing. Clinical and Laboratory Standards Institute. Available: http://www.microbiolab-bg.com/CLSI.pdf. Accessed 20 September 2015.

  19. Poonsuk K, Tribuddharat C, Chuanchuen R. Class 1 integrons in Pseudomonas aeruginosa and Acinetobacter baumannii isolated from clinical isolates. Southeast Asian J Trop Med Public Health. 2012; 43(2): 376-84.

  20. Azizi O, Shakibaie MR, Modarresi F, Shahcheraghi F. Molecular detection of Class- D (OXA) carbapenemase genes in biofilm and non-biofilm forming clinical isolates of Acinetobacter baumannii. Jundishapur J Microbiol.  2015; 8(1): e21042.

  21. Bonomo RA, and Szabo D. Mechanisms of multidrug resistance in Acinetobacter species and Pseudomonas aeruginosa. Clin Infect Dis. 2006; 43 (Suppl 2): S49-56.

  22. Phu VD, Wertheim HF, Larsson M, Nadjm B, Dinh QD, Nilsson LE, et al. Burden of hospital acquired infections and antimicrobial use in Vietnamese adult intensive care units. PLoS One. 2016; 11(1): e0147544.

  23. Mengeloğlu FZ, CopurÇiçek A, Koçoğlu E, Sandallı C, Budak EE, Ozgümüş OB. Carriage of Class 1 and 2 integrons in Acinetobacter baumannii and Pseudomonas aeruginosa isolated from clinical specimens and a novel gene cassette array: blaOXA-11-cmlA7. Mikrobiyol Bul. 2014; 48(1): 48-58.

  24. Gu B, Tong M, Zhao W, Liu G, Ning M, Pan S, et al. Prevalence and characterization of Class 1 integrons among Pseudomonas aeruginosa and Acinetobacter baumannii isolates from patients in Nanjing, China. J Clin Microbiol. 2007; 45(1): 241-3.

  25. Huang C, Long Q, Qian K, Fu T, Zhang Z, Liao P, et al. Resistance and integron characterization of Acinetobacter baumannii in a teaching hospital in Chongqing, China. New Microbes New Infect. 2015; 8: 103-8.

  26. Nikokar I, Tishayar A, Flakiyan Z, Alijani K, Rehana-Banisaeed S, Hossinpour M, et al. Antibiotic resistance and frequency of Class 1 integrons among Pseudomonas aeruginosa, isolated from burn patients in Guilan, Iran. Iran J Microbiol. 2013; 5(1): 36-41.

  27. Taherikalani M, Maleki AB, Sadeghifard N, Mohammadzadeh D, Soroush S, Asadollahi P, et al. Dissemination of Class 1, 2 and 3 integrons among different multidrug resistant isolates of Acinetobacter baumannii in Tehran hospitals, Iran. Pol J Microbiol. 2011; 60(2): 169-74.