Susceptibility profiles of bacteria causing urinary tract infections in Southern Tunisia.

OBJECTIVES: The aim of this study was to determine the epidemiological profile and antibiotic resistance of bacteria responsible for urinary tract infections (UTIs) diagnosed in the Department of Microbiology of the Hospital Regional Houcine Bouzaiene (Gafsa) in southwest Tunisia.

METHODS: All cytobacteriological urine samples analysed from 1 January 2015 to 30 June 2016 were included in the study. The criteria used to define UTI were leukocyturia >104 cells/mL and bacteriuria >105 CFU/mL.

RESULTS: Among 12678 urine samples, 2093 (16.5%) met the criteria of UTI. The majority of infections were in outpatients (92.1%). Gram-negative bacteria were the main identified organisms (1980/2093; 94.6%), whilst Gram-positive bacteria represented only 5.4% (113/2093). The most frequently identified organisms were Enterobacteriaceae (1938/2093; 92.6%), including 1404 (67.1%) Escherichia coli and 268 (12.8%) Klebsiella pneumoniae. Extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) were identified and represented 3.6% (70/1938) of the total Enterobacteriaceae. The proportion of community ESBL-E was 3.4% (61/1787). The resistance rate of E. coli and K. pneumoniae to amoxicillin and ticarcillin was elevated; however, monobactams and especially carbapenems (imipenem), colistin and amikacin retained good activity.

CONCLUSIONS: Excessive use of antibiotics in hospitals and the community is responsible for the appearance of new resistance profiles; thus, routine monitoring of antibiotic resistance of uropathogenic bacteria must be performed in hospitals as well as in private laboratories in order to prescribe appropriate antibiotics.