Assessment of Biofilm Formation among the Clinical Isolates of Escherichia coli in a Tertiary Care Hospital

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Bedobroto Biswas
Naik Shalini Ashok
Deepesh Nagarajan
Md Zaffar Iqubal


Aims: Identification and grading of the Escherichia coli according to their biofilm production capability.

Study Design:  Cross-sectional study.

Place and Duration of Study: This was conducted in Department Microbiology at M.S. Ramaiah Medical college and Hospital, Bengaluru from March 2017 to August 2017.

Methodology: A total of 55 non repetitive Escherichia coli isolates were identified from various clinical samples like urine, pus ,tissue and peritoneal fluids .All the organisms were isolated in pure culture and biofilm formation was detected in vitro by Gold standard TCP (Tissue culture plate) method. Organisms were incubated for an extended period of 48 hours and the biofilms were detected by acetone alcohol elution method. Organisms were categorized as strong, moderate, weak and no biofilm producers based on the obtained OD value of the elute.

Results: Majority of the isolates of Escherichia coli were obtained from catheterized urine culture (67.03%) followed by pus (25.50%).Most of the isolates were capable of forming biofilm in vitro by tissue culture plate method except a few (9.1%). 40% of the isolates were strong biofilm formers which had >4 ODC. 25.5% showed medium biofilm-forming capability and rest 25.5% showed weak biofilm formations in vitro.

Conclusion: The ability to form biofilm from a species can give us a better understanding of the biofilm-related infections pertaining to the particular group. Detection of biofilms remains a most important determinant to approximate the incidence of such infections. Categorization of organisms according to their biofilm formation may help us understand the frequency of biofilm-associated infections, and thus take necessary precautions to avoid the problem. Further studies involving the detection of biofilm may be conducted and the tests can be implemented in routine diagnostic microbiology to assess the usefulness of the methods in detection of biofilm-related infections.

Escherichia coli, biofilm, Foley’s catheter, tissue culture plate.

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How to Cite
Biswas, B., Shalini Ashok, N., Nagarajan, D., & Iqubal, M. Z. (2020). Assessment of Biofilm Formation among the Clinical Isolates of Escherichia coli in a Tertiary Care Hospital. Microbiology Research Journal International, 30(1), 26-32.
Original Research Article


Donlan Rodney M. Biofilm Formation: A Clinically Relevant Microbiological Process. Clinical Infectious Diseases. 2001;33(8):1387-1392.

Ceri H. et al. The Calgary Biofilm Device: New technology for rapid determination of antibiotic susceptibilities of bacterial biofilms. Journal of Clinical Microbiology. 1999;37(6):1771–1776.

Makvana S, Krilov LR. Escherichia Coli Infections. Pediatrics in Review. 2015; 36(4):167–171.

Fasciana et al. Virulence factors and antimicrobial resistance of Escherichia coli ST131 in community-onset healthcare-associated infections in Sicily, Italy. Pharmacologyonline (Special Issue). 2017; 12-21.

Beloin C, et al. Escherichia Coli Biofilms. Current Topics in Microbiology and Immunology Bacterial Biofilms. 2008;249–289.
DOI: 10.1007/978-3-540-75418-3_12

Ansari Ma, et al. Anti-Biofilm efficacy of silver nanoparticles against MRSA and MRSE Isolated from Wounds in a Tertiary Care Hospital. Indian Journal of Medical Microbiology. 2015;33(1)101.

Christensen GD, et al. Adherence of coagulase-negative Staphylococci to Plastic Tissue Culture Plates: A Quantitative Model for the Adherence of Staphylococci to Medical Devices. Journal of Clinical Microbiology. 1985;22(6):996–1006.

Prashanth K, et al. Correlation between biofilm production and multiple drug resistance in imipenem resistant clinical isolates of Acinetobacter baumannii. Indian Journal of Medical Microbiology. 2008; 26(4):333.

Dror Naama et al. Advances in microbial biofilm prevention on indwelling medical devices with emphasis on usage of acoustic energy. Sensors. 2009;9(4):2538–2554.

Jacobsen SM, et al. Complicated catheter-associated urinary tract infections due to Escherichia Coli and Proteus Mirabilis. Clinical Microbiology Reviews. 2008;21(1): 26–59.

Gelosia A, et al. Phenotypic and genotypic markers of Staphylococcus Epidermidis Virulence. Clinical Microbiology and Infection. 2001;7(4):193–199.

Neopane Puja, et al. In Vitro Biofilm formation by Staphylococcus aureus Isolated from wounds of hospital-admitted patients and their association with antimicrobial resistance. International Journal of General Medicine. 2018;11:25–32.

Patel Fm, et al. Detection of biofilm formation in device associated clinical bacterial isolates in cancer patients. Sri Lankan Journal of Infectious Diseases. 2016;6(1):43.

Stickler DJ. Bacterial biofilms and the encrustation of urethral catheters. Biofouling. 1996;9(4):293–305.

Majumder Md. Mahabubul Islam, et al. Microbiology of catheter associated urinary tract infection. Microbiology of Urinary Tract Infections - Microbial Agents and Predisposing Factors; 2019.

Papa R, et al. Biofilm formation in carbapenemase-producing Pseudomonas Spp. and Acinetobacter baumannii Clinical Isolates. International Journal of Infectious Diseases. 2018;73:119– 120.

Mandakhalikar Kedar Diwakar et al. Extraction and quantification of biofilm bacteria: Method Optimized for Urinary Catheters. Scientific Reports. 2018;8(1).