Morphological and Bactericidal Effects of Amikacin, Meropenem and Imipenem on Pseudomonas aeruginosa

نویسندگان

  • Mohsen Moghoofei
  • Hossein Fazeli
  • Farkhondeh Poursina
  • Bahram Nasr Esfahani
  • Sharareh Moghim
  • Hamid Vaez
  • Shima Hadifar
  • Hajieh Ghasemian Safaei
چکیده

BACKGROUND Pseudomonas aeruginosa might be converted to coccoid bacteria under antibiotic stress. Bacterial conversion would increase resistance to antibiotics due to changes in cell wall crosslink or decreased metabolic activity. Morphology of P. aeruginosa under stress conditions (presence of antibiotics) can be changed to elongated bacilli, U shape and finally coccoid bacteria. Results of several researches showed that coccoid bacteria are one of the most important aspects of drug resistance. It would be the major reason for treatment failure. OBJECTIVES The aim of this study was to determine in vitro morphological and bactericidal effects of amikacin, meropenem and imipenem on P. aeruginosa isolated from clinical specimens. MATERIALS AND METHODS Eight P. aeruginosa isolates obtained from clinical samples of burned patients and standard strain ATCC 27853 were used in this study. Isolates were identified by biochemical tests and confirmed by PCR method using ITS specific primer. Minimum inhibitory concentrations (MICs) of three antibiotics were determined by E-test method. Bacteria were exposed to antibiotics at different concentrations. Bacterial morphology in different days was examined by specific microscope and viability of isolates was examined by flow cytometry. RESULTS All used antibiotics at sub MIC concentration had capability to induce coccoid bacteria. The highest rate of induced coccoid bacteria was 98.2% after 8 days, with contribution of imipenem and meropenem at 2 μg/mL concentration. Amikacin at 4 μg/mL concentration induced lower rate of coccoid bacteria (55.05%). Amikacin had a strong bactericidal effect on coccoid bacteria at 8 μg/mL concentration. Imipenem and meropenem showed very weak bactericidal effect on coccoid bacteria. CONCLUSIONS Induction of coccoid form of P. aeruginosa may be one of the important reasons for antibiotic treatment failure; therefore, prescribed dose of antibiotics should be carefully managed to prevent increasing antibiotic resistance and coccoid bacteria induction.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

In vitro antimicrobial effects of aztreonam, colistin, and the 3-drug combination of aztreonam, ceftazidime and amikacin on metallo-β-lactamase-producing Pseudomonas aeruginosa

BACKGROUND There are limited choice of antimicrobial agents to treat infection with metallo-beta-lactamase-producing Pseudomonas aeruginosa. We evaluate the antimicrobial effects of aztreonam alone, colistin alone and the 3-drug combination of aztreonam, ceftazidime and amikacin on 23 strains of metallo-beta-lactamase-producing P. aeruginosa by time-killing tests. METHODS Strains used were fr...

متن کامل

Serum bactericidal activity and killing rate for volunteers receiving imipenem, imipenem plus amikacin, and ceftazidime plus amikacin against Pseudomonas aeruginosa.

Serum bactericidal activity against 20 strains of Pseudomonas aeruginosa was studied in 10 volunteers after administration of imipenem (25 mg/kg), imipenem (25 mg/kg) plus amikacin (7.5 mg/kg), and ceftazidime (25 mg/kg) plus amikacin (7.5 mg/kg). Eight strains were susceptible and 12 were resistant to ticarcillin. Serum levels were measured microbiologically after 30 and 60 min and were, respe...

متن کامل

Prevalence rate of resistance to ciprofloxacin among clinical pseudomonas aeruginosa isolates in Kurdistan province, west of Iran

Background and Aim: Infection by drug resistant Pseudomonas aeruginosa causes important therapeutic problems. The present study was performed to investigate the antibiotic susceptibility and prevalence of antimicrobial resistance genes in P. aeruginosa. Materials and Methods: In this cross sectional study, 61 clinical P. aeruginosa isolates were collected in Sanandaj between April and September...

متن کامل

Antibacterial properties of BO-2727, a new carbapenem antibiotic.

BO-2727 is a new injectable carbapenem antibiotic with broad-spectrum, potent antibacterial activity. The in-vitro and in-vivo antibacterial activities of BO-2727 were compared with those of meropenem, imipenem and biapenem. BO-2727 was four- to eight-fold more active in vitro than meropenem, imipenem and biapenem against methicillin-resistant Staphylococcus aureus, inhibiting more than 90% of ...

متن کامل

Antibiotic utilization and Pseudomonas aeruginosa resistance in intensive care units.

Pseudomonas aeruginosa is one of the most frequent and dangerous pathogens involved in the etiology of severe nosocomial infections. A retrospective observational study was conducted at all intensive care units of the University Hospital in Olomouc, Czech Republic (155 ICU beds). Complete antibiotic utilization data of the ICUs in the period of 1999 to 2008 were processed according to ATC/DDD s...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره 8  شماره 

صفحات  -

تاریخ انتشار 2015