Biofilm formation by Methicillin resistant Staphylococcus aureus and its relation to antibiotic resistance in Thi-qar province/Iraq


  • Saad A. Atiyah Dept. Microbiology\College of Medicine\University of Thi-Qar


Biofilm, Staphylococci, antibiotic resistance


    Methicillin resistant Staphylococcus aureus is one of the most dangerous pathogens in the community and the hospital environment for its high resistance to antibiotics and the production of a number of virulence agents such as toxins and biofilm. The study aims to determine the ability of local isolates to produce the biological membrane and its relationship to resistance to antibiotics. A cross sectional study include (37) isolates of methicillin-resistant S. aureus from the burn department at Al-Hussein Teaching Hospital in Thi Qar province/Iraq for the period April-October 2015, The capacity of bacteria to produced biofilm was done by  micro plate technique and the antibiotic susceptibility test for vancomycin,  amikacin,  ciprofloxacin, norfloxacin, cefotaxime and amoxicillin-Claviolinate using the diffusion technique of antibiotic disks. The study showed that 64.9% of the MRSA isolates were able to form biofilm, while the isolates were fully resistant to the used beta-lactam antibiotics. But, the 94.6% of the isolates were sensitive to the vancomycin. There was no significant statistical relationship between the antibiotic resistance and the ability of bacteria to produce the biofilm except for the ciprofloxacin. The study showed that the local MRSA isolates have a high ability to produce the biological membrane and antibiotic resistance with the exception of the vancomycin with a relationship between the resistance to ciprofloxacin and the production of the biological membrane by bacteria. Therefore, the study recommends the use of vancomycin in medical sites to treat the infections caused by MRSA to prevent the spread and development of these resistant strains.


Howden BP, Davies JK, Johnson PD, Stinear TP, Grayson ML. (2010). Reduced vancomycin susceptibility in Staphylococcus aureus, including vancomycin-intermediate and heterogeneous vancomycin-intermediate strains: resistance mechanisms, laboratory detection, and clinical implications. Clin. Microbiol. Rev. 23(1):99-139.

Brooks GF, Butel, JS and Morse SA, (2004) . Jawetz, Melnick, & Adelberg's Medical Microbiology, 23rd Edition McGraw-Hill Companies .

Turlej A, Hryniewicz W, Empel J. (2011) Staphylococcal cassette chromosome mec (Sccmec) classification and typing methods: an overview. Pol. J Microbiol. 60(2):95-103.

Chambers HF. (2011). The changing epidemiology of Staphylococcus aureus. Emerg. Infect. Dis. 7:178–82.

Cox RA, Conquest C, Mallaghan C, Marples RR. (1995). A major outbreak of methicillin resistant Staphylococcus aureus caused by a new phage type (EMRSA-16) J Hosp. Infect. 29:87–106.

Deurenberg RH, Stobberingh EE. (2009). The molecular evolution of hospital- and community-associated methicillin-resistant Staphylococcus aureus. Curr. Mol. Med. 9(2):100-15.

Saha B, Singh AK, Ghosh A. and et al. (2008). Identification and characterization of a vancomycin-resistant Staphylococcus aureus isolated from Kolkata (South Asia) J Med. Microbial. 57:72–9.

Hiramatsu K, Hanaki H, Ino T, et al. (1997). Methicillin-resistant Staphylococcus aureus clinical strain with reduced vancomycin susceptibility. J Antimicrob. Chemother. 40:135.

Costerton JW, Stewart PS, Greenberg EP. (1999). Bacterial biofilms: a common cause of persistent infections. Science. 21(284):1318-22.

Eiichi A, Koichi M, Ritsuko M, et al. (2004). Biofilm formation among methicillin-resistant Staphylococcus aureus isolates from patients with urinary tract infection. Acta Med. Okayama 58 (4): 207-214.

Forbes BA, Daniel FS and Alice SW, (2007). Bailey and Scott's diagnostic microbiology. 12th. ed. ,Mosby Elsevier company , USA

Christensen GD, Simpson WA, Younger JJ, et al. (1985). Adherence of coagulase-negative staphylococci to plastic tissue culture plates: a quantitative model for the adherence of staphylococci to medical devices. J Clin. Microbiol. 22:996–1006.

Frazee BW , Lynn J , Charlebois ED , et al (2005). High prevalence of methicillin resistant Staphylococcus aureus in emergency department skin and soft tissue infections . Ann. Emerg. Med. 45 : 311 – 20 .

Moran GJ , Amii RN , Abrahamian FM , et al. (2005). Methicillin-resistant Staphylococcus aureus in community-acquired skin infections . Emerg. Infect. Dis. 11 : 928 – 30 .

Singh R, Ray P, Das A, Sharma M. (2010). Penetration of antibiotics through Staphylococcus aureus and Staphylococcus epidermidis biofilms. J Antimicrob. Chemother. 65:1955 - 1958;

Mack D, Fischer W, Krokotsch A, et al. (1996). The intercellular adhesin involved in biofilm accumulation of Staphylococcus epidermidis is a linear beta-1,6-linked glucosaminoglycan: purification and structural analysis. J Bacteriol. 178:175- 183

Croes, S, Deurenberg, RH, Boumans, ML, et al., (2009). Staphylococcus aureus biofilm formation at the physiologic glucose concentration depends on the S. aureus lineage. BMC Microbiology.

Smith, SM, Eng, R and Tecson-Tumang, F. (1989). Ciprofloxacin therapy for methicillin-resistant Staphylococcus aureus infections or colonizations. Antimicrob. Agents Chemother. 33(2): 181–184.

Morvarid, S, Ahya, AA, Fereshteh, S, et al., (2014). Eradication of Pseudomonas aeruginosa biofilms using the combination of n-butanolic Cyclamen coum extract and ciprofloxacin. Jundishapur J Microbiol. 7(2).

Vivek V. Harjai K and Chhibber S. (2009). Restricting ciprofloxacin-induced resistant variant formation in biofilm of Klebsiella pneumoniae B5055 by complementary bacteriophage treatment. J Antimicrob. Chemother.64: 1212– 1218.

Lewis K. (2010). Persister cells. Annu. Rev. Microbiol. 64:357 – 372.

Xu KD, McFeters GA and Stewart PS. (2000). Biofilm resistance to antimicrobial agents. Microbiology 146:547 - 549;