| Introduction: Pseudomonas aeruginosa (P. aeruginosa) is one of the most commoncauses of difficult-to-treat lung infections.
The aim of study wasto evaluate susceptibility patterns of biofilm-forming P. aeruginosa atmechanically ventilated patients.
Materials & Methods: Totally,50 P. aeruginosa isolates obtained from endotracheal aspirate specimensin patients of cardiosurgical
intensive care unitswho were intubated for more than 48h. Detection of biofilm-forming carried out by tube and microtitre
assaysandsusceptibility testing was performed by Kirby-Bauer method.
Results: Resistance to piperacillin, gentamicin, ciprofloxacin, aztreonam, ceftizoximeand levofloxacin has been more than 60%.
Resistance to colistinwas not seen.Multidrug resistant (MDR) was detected in 65% of the isolates. In the present study, 28 of
50(56%) and 19 of 50 (38%) isolates were biofilm-forming by microtitreand tube methods, respectively. Overall,biofilm-forming
isolates were more resistant than non-biofilm-forming P. aeruginosa to antibiotics. The biofilm formation was significantly higher
instrains that were MDR(p < 0.05).
Conclusion: Themost effective drug against P. aeruginosawas colistin, followed by carbapenems, amikacin and
cefepime.P. aeruginosa biofilms were extensively more resistant to furthermost antibiotics tested. Therefore, biofilm formation
may need more attention when antibiotic treatment is selected for intubated patients. |