The impact of fluoroquinolones use on antibiotic resistance in an intensive care burn department.

BACKGROUND

Fluoroquinolones (FQ) use has been identified as a risk factor for colonization and infection to methicillin resistant Staphylococcus aureus(MRSA), Pseudomonas aeruginosae multiresistant(PMR) , Acinetobacter multiresistant (AMR) and multidrug resistant bacteria(MDRB).

AIM

Our study proposes to measure the annual antibiotic use of FQ and antimicrobial resistance in P. aeruginosa, S. aureus, Klebsiella pneumoniae and A. baumannii in an intensive care burn unit.

METHODS

The study was conducted during a 4 year period (1 January 2000 to 31 December 2003). Antimicrobial susceptibility testing was performed using the disk diffusion method as recommended by the French Society of Microbiology. The consumption of the following antibiotics: ofloxacin, ciprofloxacin was expressed as the antimicrobial use density (AD) taking into account the quantity of antibiotics in Grams converted to defined daily doses (DDD) and the number of day hospitalization. Statistical significance was defined as p value < 0.05 for the corresponding correlation coefficient.

RESULTS

There were statistically significant relationship between use of ciprofloxacin and resistance in P. aeruginosa to this drug (rs=0.95, p<0.05). Moreover, the ciprofloxacin consumption was correlated with resistance to imipenem (rs=0.95, p<0.05) and ceftazidime (rs=0.95, p<0.05) in P. aeruginosa . A restriction use of ciprofloxacin has been taken during 2003, it is followed by a significant decrease of resistance to imipenem, ceftazidime and ciprofloxacin in P. aeruginosa (p<0, 05). The use of fluoroquinolones was correlated significantly with MRSA (rs=0.96, P<0.05) . The restriction use of FQ was significantly associated with a decrease of MRSA. The consumption of ciprofloxacin was also correlated (P<0.05) with resistance of ceftazidime in K. pneumoniae. However, there is not a correlation (P> 0.05) between fluoroquinolones use and resistance in A. baumannii as well in ciprofloxacin, imipenem and ceftazidime. Our study illustrates the pressure of selection of fluoroquinolones use in the development of MDRB. The use and or the duration of treatment with theses antibiotics should be rationalised as part of efforts to control the emergence of multidrug resistant bacteria.