Naslov
In vitro effect of subMICs of antibiotics on the adherence ability and morphology of Pseudomonas aeruginosa strains isolated from patients with urinary tract infection

Autori
Vraneš, Jasmina ; Bedenić, Branka ; Turković, Branko

Izvornik
Clinical microbiology and infection (1198-743X) 11 (2005), Suppl. 2; 592-593

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, kongresno priopcenje, znanstveni

Ključne riječi
Pseudomonas aeruginosa ; urinary tract infections ; antibiotics ; subinhibitory concentrations ; adherence

Sažetak
Objectives: The ability of Pseudomonas aeruginosa to adhere to the surface of mucous membranes of the human body is considered the initial step in its colonization and subsequent infection. The aim of this study was to examine the influence of subminimal inhibitory concentrations (subMICs) of ceftazidime and ciprofloxacin on the morphology and adherence ability of wild-type P. aeruginosa strains to Buffalo green monkey kidney (BGMK) cell line. Methods: A total of 14 strains isolated from urine of patients with urinary tract infection (UTI) were used. Bacterial adherence to the BGMK cell line was tested before and after treatment with antibiotics and detected by means of an immunofluorescence staining. Comparisons were made between the morphology before and that after exposure of strains to 1/2, 1/4, 1/8, 1/16 and 1/32 MIC of antibiotics, as well as between the number of bacteria attached to the BGMK cells before and the number after their exposure to the same concentrations of antibiotics. Results: Significant dose dependent reduction of P. aeruginosa adherence ability was observed, wich correlated with the alterations in bacterial cell morphology. After exposure of strains to subMICs of antibiotics, normal shapes and filaments were noted. The greatest filamentation and the greatest loos of adherence ability occurred at 1/2 MIC of ceftazidime. The lenght of filaments decreased as the concentration of this antibiotic was being reduced, and at the concentration of 1/32 MIC normal bacterial morphology was detected. Treatment with subMICs of ciprofloxacin resulted in shorter filaments. Using the paired t test to compare the number of adhered bacteria before and after exposure to subMICs of antibiotics, a statistically significant difference was determined after exposure of strains to 1/2, 1/4, 1/8 and 1/16 MIC of ceftazidime, and to 1/2, 1/4 and 1/8 of ciprofloxacin. Conclusion: The results of this study have shown that the adherence capacity of P. aeruginosa strains isolated from urine of patients with UTI was significantly decreased after exposure to subMICs of ceftazidime and ciprofloxacin. SubMICs of antibiotics affected not only the adherence ability of bacteria, but also their morphology.

Izvorni jezik
Engleski

Znanstvena područja
Temeljne medicinske znanosti, Kliničke medicinske znanosti

POVEZANOST RADA