PHENOTYPIC DETECTION OF FLUOROQUINOLONE-MODIFYING ENZYMES AMONG GRAM NEGATIVE BACTERIA ISOLATED FROM CLINICAL SPECIMENS IN BENIN CITY, EDO STATE.

ABSTRACT

Fluoroquinolones are among the drug of choice in the treatment of bacterial infections. Resistance to fluoroquinolones is either via efflux pump, mutation or production of modifying enzymes. This study aimed at determining the prevalence of fluoroquinolone modifying enzymes among Gram negative bacteria recovered from clinical specimens in a secondary hospital in Benin City, Nigeria. A total of 1033 clinical specimens obtained from various sample sites were used for this study. These were processed bacteriologically to recover bacteria. Gram negative bacilli were processed further through identification and susceptibility testing using standard microbiological techniques. Ciprofloxacin-resistant Gram negative bacilli were also processed further to phenotypically determine the presence of fluoroquinolone modifying enzyme (FME) using standard techniques. A total of 642(62.15%) out of 1033 specimens were infected with the rate of infection being significantly higher in wound swabs and Pseudomonas aeruginosa being the most prevalent Gram negative bacteria recovered 243(86.48%). A total of 217(33.80%) isolates were resistant to ciprofloxacin with Aeromonas spp having the highest rate of resistance 4(80%) (P=0.0002). Of the 217 ciprofloxacin-resistant bacteria, 108(49.77%) produced FME. The genera of the various Gram Negative isolates did not significantly affect the prevalence of FME (P = 0.2758). Acinetobacter and Citrobacter spp recovered from males produced more FME than the same isolates recovered from females (P < 0.05), Ciprofloxacin resistant isolates recovered from catheter tips had the highest rate of FME production compared with ciprofloxacin-resistance recovered from other isolates (P < 0.0001). Only ciprofloxacin-resistant K. pneumoniae recovered from in-patients were significantly higher producers of FME compared with their counterparts recovered from out-patients (in-patient vs out-patient; 73.81% vs 20%; P = 0.0304). There was no significant difference in the susceptibility profile between FME-producing and FME non-producing-ciprofloxacin resistant Gram Negative Bacteria. A relatively high prevalence of FME producing ciprofloxacin resistant Gram negative bacilli was recorded in this study. Measures to reduce the rate of FME-producing ciprofloxacin-resistant Gram negative bacteria are advocated.