IN VITRO BIOFILM FORMATION AND ANTIMICROBIAL SUSCEPTIBILITY PATTERN OFUROPATHOGENS IN PATIENTS WITH CATHETER ASSOCIATED URINARY TRACTINFECTIONS (CAUTIs)

BACKGROUNDMicrobial biofilms pose serious health hazards for persons requiring indwelling medical devices.Biofilms are inherently resistant to many antibiotics. Thus the present study aims at detection of in vitro biofilm formation by uropathogens in Catheter Associated Urinary Tract Infections (CAUTIs) and also to study the antimicrobial susceptibility pattern of the biofilm producers and nonbiofilm producers.METHODThis prospective analysis included 70 catheter tips and urine samples from catheterised patients with signs and symptoms of Urinary Tract Infections.Following identification,all isolates were subjected to antimicrobial susceptibility testing by modified Kirby-Bauer disc diffusion method.Detection of biofilm formation was done by Congo red agar method, tube adherence method and Microtitre platmethod.RESULTSKlebsiella oxytoca was the predominant isolate (34.3) causing CAUTI, followed by Escherichia coli (18.6), Klebsiella pneumoniae (17.1), Proteus vulgaris (12.9), Pseudomonas aeruginosa (7.1), Proteus mirabilis (5.7),Citrobacter freundii (2.9) and Staphylococcus epidermidis (1.4). Biofilm producers showed significantly increased resistance to all the first line antibiotics than the non-biofilm producers. Microtitre plate method was more quantitative and reliable for detecting biofilm production, followed by tube adherence method and Congo red agar method.CONCLUSIONKlebsiella oxytoca was the most frequent isolate (24),of which 16 were biofilm producers.The antimicrobial susceptibility pattern showed that quinolones were the least active drugs and aminoglycosides showed highest activity among first line drugs.The uropathogens showed highest sensitivity to carbapenems.