Pseudomonas aeruginosa Clinical Isolates: Antibiogram Profile and Biofilm Formation

Abstract

Background: The gram-negative bacterium, Pseudomonas aeruginosa belongs to a vast genus of obligate aerobic, nonfermenting, saprophytes, which are present in water, soil and on plants. Moreover, P. aeruginosa can be frequently isolated from tap water. In its natural habitat, this organism is endowed with weak pathogenic potential. However, its profound ability to survive on inert materials, its minimal nutritional requirement, tolerance to a wide variety of physical conditions and relative resistance to several antimicrobial agents and antiseptics, contribute enormously to its ecological success and its role as an effective opportunistic pathogen. P. aeruginosa is a notoriously difficult organism to control with antibiotics or disinfectants and has become increasingly recognized as an emerging opportunistic pathogen of clinical relevance. Multi-drug-resistant Pseudomonas aeruginosa (MDRPA) are often isolated from patients suffering from nosocomial infections, particularly those who are admitted to intensive care unit (ICU).[3] Thus, infections caused by P.aeruginosa especially in ICU patients are problematic because the organism apart from being inherently resistant to many drug classes, is able to acquire resistance to many effective antimicrobial drugs and therefore infections caused by P. aeruginosa are frequently life threatening and difficult to treat [4,5] Such multidrug resistance could be due to the slowly growing state of P. aeruginosa in the deeper layers of thick biofilms, which the organism has a tendency to form in many in vivo situations[6] Clinical isolates of Pseudomonas aeruginosa often exhibit multidrug resistance due to their inherent ability to form biofilms. Drug resistance in Pseudomonas aeruginosa is a major clinical problem, especially in the management of patients with nosocomial infections and those who are under indwelling medical devices. The man objective of this study is to evaluate the biofilm forming abilities of the clinical isolates of Pseudomonas aeruginosa and to correlate biofilm formation with multidrug resistance.