Evaluation of resistance to fluoroquinolones in clinical isolates of escherichia coli

ABSTRACT

The evaluation of resistance to ciprofloxacin [CIP] in Escherichia coli [n=1112] isolated from clinical specimens including urine, pus, high vaginal swabs, etc. was carried out at Rawalpindi General Hospital, Rawalpindi during the years 2002- 2005. The isolates were identified by colonial morphology, gram staining, and biochemical tests like indole, citrate and TSI. The antibiotic susceptibility of these isolates was determined by Kirby-Bauer disk diffusion method according to the standard guidelines of Clinical Laboratory Standards Institute [CLSI]. During the year 2002 resistance to ciprofloxacin was 49.19% [n=187], in the year 2003 it was 47.5% [n=297], in year 2004 was 59.03% [n=332], in year 2005 was 46.28% [n=296]. When resistant isolates from different sources were compared E. coli uropathogens varied between 45.2 to 58.53% during the four year. While pus isolates in 2003 were highly resistant [69% resistance] and isolates from high vaginal swab showed peak resistance in 2004 [66%] Fig. 3 table 4. In the year 2002, four fluoroquinolones [FQs] i.e. ofloxacin [OFX], ciprofloxacin [CIP], enoxacin [ENX] and sparfloxacin [SPX] were included in the study while norfloxacin [NOR] was tested against urinary isolates only. During that year 203 isolates were identified as E. coli; 124 from urine, 45 from pus, 21 from high vaginal swabs, and 13 from other sources. Highest resistance was seen in isolates from urine ranging from 54-68% against these FQs