Biofilm production and its correlation with antibiotic resistance pattern among clinical isolates of Pseudomonas aeruginosa in a tertiary care hospital in north-east India

Swarnatrisha Saha, Ksh Mamta Devi, Shan Damrolien, Kh. Sulochana Devi, Krossnunpuii ., Kongbrailatpam Tharbendra Sharma


Background: Pseudomonas aeruginosa is an ubiquitous pathogen capable of surviving in a variety of environmental conditions. It is increasingly gaining importance as a multidrug resistant nosocomial pathogen. Biofilm acts as a barrier, reducing the penetration of these drugs and consequently, preventing them from exercising their actions. The aim of this study is to isolate and identify Pseudomonas aeruginosa from various clinical specimen and to find out their production of biofilms and their correlation with antibiotic susceptibility pattern.

Methods: All Pseudomonas aeruginosa over a period of 1 year were isolated and identified from clinical specimens and antibiotic susceptibility test was done following standard operative procedures. Biofilm detection was done by Congo Red Agar method (CRA).

Results: 134 isolates of Pseudomonas aeruginosa was isolated. Maximum isolates were isolated from sputum samples 55 (41%) and most were from wards 68 (51%) giving a probability of increased healthcare associated infections. Biofilm production by the isolates was seen in 39 (29%). All the biofilm producing isolates shows more resistant pattern in comparison to non-biofilm producers. 69% of Imipenem and 82% of Meropenem resistant isolates produce biofilm. All the P. aeruginosa including MDR and biofilm forming strains were sensitive to Colistin.

Conclusions: Resistance to antimicrobial agents is the most important feature of biofilm infections. Ability of P. aeruginosa to form biofilms renders antibiotic treatments inefficient and therefore promotes chronic infectious diseases.  As a result, infections caused by bacterial biofilms are persistent and very difficult to eradicate.


Antibiotic susceptibility test, Biofilm, Multidrug resistant, Pseudomonas aeruginosa

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