Frequency and Antimicrobial Resistance of Escherichia coli in Patients with Community- Acquired Urinary Tract Infections

Abstract

This study was carried out in Khartoum State during the period from November 2008 to March 2009, to determine the frequency and antimicrobial resistance of E. coli in patients suffering from community-acquired urinary tract infections. Two hundreds and nine urine specimens were collected from patients attended Khartoum Teaching Hospital, Gaffer Ibn Auff specialized Hospital for Children and Khartoum North Teaching Hosptal. The specimens were cultured on blood and MacConkey,s agars for primary isolation of the pathogen. Identification of the isolates was done by colonial morphology, Gram's stain and biochemical tests using API 20 E (Analytical profile index). Modified Kirby-Bauer disc diffusion method was adopted to evaluate the resistance rate of E. coli to nitrofurantoin, amoxycillin, nalidixic acid, amikacin, co-trimoxazole, amoxiclav and ciprofloxacin. Minimum inhibitory concentration (MIC) of nitrofurantoin, nalidixic acid, amikacin, amoxiclav and co-trimoxazole, were determined by E. test. Of the two hundred and nine urine specimens examined, 112(54%) gave significant growth, 44(21%) isolates found to be E. coli. Furthermore, the result revealed that the antimicrobial resistance of E. coli was as follows; amoxycillin (100%), co-trimoxazole (69%), amoxiclav (66%), nalidixic acid (59%), ciprofloxacin (8%), amikacin (5%), nitrofurantoin (2.3%). The result indicated that the MIC, MIC 50 and MIC90 were as follows; nitrofurantoin (>240ug/ml each), nalidixic Acid (0.5->240ug/ml, >240ug/ml and >240), co- trimoxazole (0.25- >240ug/ml, >240ug/ml and |> 240ug/ml), amikacin (0.5-4ug/ml, 2ug/ml and 4ug/ml) and amoxiclav (0.5-4ug/ml, 4ug/ml and 4ug/ml). The study concluded that the responsipility of E. coli of community acquired urinary tract infections is noticeably high. The antimicrobial resistance of E. coli to traditionally used antimicrobial agents was high too.