Study of antibiotic resistance and anti-biofilm formation of Pseudomonas aeruginosa isolated from clinical samples in Kerman hospitals, Iran

BACKGROUND AND OBJECTIVESPseudomonas aeruginosa is an opportunistic pathogen in the hospital environment that associated with several human infections. Treatment of infections caused by P. aeruginosa is one of the biggest medical problems due to the formation of biofilm and widespread antibiotic resistance. Accordingly, the aim of this research was to investigate antibiotic resistance and anti-biofilm formation of Pseudomonas strains collected from hospitalized in Kerman, Iran in ۲۰۲۳.MATERIALS AND METHODSIn this project, ۳۰ isolates of Pseudomonas aeruginosa were isolated from clinical samples in Kerman hospitals. Biochemical tests were used for bacteria identification. The antibiotic resistance was determined by Kirby-Bauer disk diffusion susceptibility test. Minimum inhibitory concentration by gentamicin was done with broth micro-dilution method. Hydrophobicity of the bacteria was investigated by xylene for biofilm analysis. Biofilm formation was examined on the surfaces of glass and plastic under static and shaking conditions. Anti-biofilm formation was evaluated using ½ and ¼ MIC of gentamicin.RESULTS AND DISCUSSIONResults showed sensitivity to gentamicin (۷۰%), ciprofloxacin (۶۰%), ofloxacin (۵۶.۶%), amikacin (۵۳.۳۵), trimethoprim sulfamethoxazol (۳۶.۶%), imipenem (۳۰%), ceftizoxime (۳.۳%). Minimum inhibitory concentration of the gentamicin was observed in concentration of ۶۴ micrograms/ml (۲۰%).Three bacteria with hydrophobicity above۷۰% and three bacteria with hydrophobicity below ۳۰% were selected for biofilm tests. Biofilm production on plastic was more than glass surface,also in shaking state was more than stationary. Quantity of total bacteria was reduced from ۸۰۰۰ to ۴۴۰۰ in ¼ MIC and ۳۶۱۰ in ½ MIC of gentamicin on biofilm formation of venous catheter.CONCLUSIONAccording to the use of plastic medical devices such as angiocaths and venous catheters and the high ability of Pseudomonas aeruginosa to create biofilm on plastic surfaces, the possibility of hospital infections with Pseudomonas is very high and the indiscriminate use antibiotics increases their resistance. These results should be considered to understand the importance of limiting antibiotics and new health care.

کلیدواژه ها:

Pseudomonas aeruginosa ، Antibiotic resistance ، Hydrophobicity ، Anti-biofilm