Evaluation of biofilm formation of pseudomonas aeruginosa isolated from al-Shifa Hospital and their susceptibility to acetic acid

الملخص EN

Biofilm forming ability is a major virulence factor of most of pathogenic bacteria.

Over 65% of health care associated infections are caused by biofilm producing organisms.

The primary objective of this cross sectional study is to evaluate the biofilm forming ability of Pseudomonas aeruginosa isolated from various departments of Al-Shifa hospital and to determine the susceptibility of the isolates for antimicrobial drugs and acetic acid.

Swabs moistened with sterile normal saline were used to swab an area of three cm2.

Samples were cultured and processed by standard microbiological procedures.

P.

aeruginosa isolates were tested for their antimicrobial susceptibility patterns, the minimum inhibitory concentration for acetic acid and the biofilm forming ability were determined using Tube method and Crystal violet assay method.

Susceptibility of P.

aeruginosa isolates for acetic acid was considered as high at Conc.

= 0.0097 mg/ml (5%), moderate susceptibility (0.156 to 0.019 mg/ml) (86%) and low susceptibility (>0.312 mg/ml) (9%).

The isolates were 100% resistance to Ceftazidime, Piperacillin (97.6%), Ciprofloxacin (28.57%), Norfloxacin (9.5%), Meropenem and Aztreonam (2.38%).

All were susceptible to Gentamicin, and Amikacin.

The results for biofilm formation showed that 16 sample were strong positive (38.09%), 18 sample moderately positive (42.85%), and eight-samples were negative (19.04%).

Biofilm forming ability of the isolates was detected in 80.9% of isolates.

In conclusion, both biofilm and antimicrobial resistance were high among the isolates.

Acetic acid showed weak/strong/moderate antimicrobial activity against P.

aeruginosa.