Characterization of Extended Spectrum β-Lactamase-ProducingEscherichia coliin Community-Acquired Urinary Tract Infections in Tunisia

Abstract

This study was conducted to investigate the molecular epidemiology of extended spectrum β-lactamase (ESBL)-producing Escherichia coli in community-acquired (urinary tract) infections (CA-UTI) in Tunisia. Between January 2007 and December 2009, 15 E. coli isolates were collected at the laboratory of microbiology of Charles Nicolle Hospital of Tunis. Microbial identification was done with conventional methods. Antibiotic susceptibility was determined by disk diffusion method and ESBL detection was done with double-disk synergy test. ESBL typing was performed by polymerase chain reaction (PCR) and sequencing. Phylogenetic groups, virulence factors, and sequence type (ST)131 were determined by PCR. Genetic relatedness between strains was examined by pulsed-field gel electrophoresis (PFGE) after restriction with XbaI. The prevalence of ESBL-producing E. coli in CA-UTI was 0.046%. The majority of isolates were multidrug resistant. ESBL types were CTX-M-15 (n=13) and SHV-12 (n=2). The most common phylogenetic group was B2 (n=11) and virulence score was greater than or equal to 9 in nine strains. PFGE revealed 12 clusters. The majority of isolates (n=14) belonged to ST131 clone and 11 of them were CTX-M producers. In conclusion, this is the first detailed documentation of CA-ESBLs producing E. coli in Tunisia. Of particular concern is the emergence in our community of the highly diffusing CTX-M-15-B2-ST131 E. coli clone, which requires strengthening surveillance measures to countervail this emergent public health problem.

Carbapenemases and extended-spectrum β-lactamases producing Enterobacteriaceae isolated from Tunisian and Libyan hospitals

“…These results suggest that blaCTX-M-15 is the most common gene responsible for mediating extended-spectrum cephalosporin resistance in these isolates. These data confirm previous studies showing that this enzyme is widely present in Tunisia [11,21,[24][25][26][27][28][29][30][31] (Table 4). [34].…”

Genotypic characteristics of multidrug‐resistant Escherichia coli isolates associated with urinary tract infections

“…Our study showed a quite higher prevalence of CTX-M ESBLs among MDR E. coli strains than that in other countries such as Tunisia (29). In addition, the prevalence of TEM-1b, OXA-1, 16S-RMTase, SHV-variants, and KPC, accompanied by CTX-M ESBLs and the frequent occurrence of PMQRs among these CTX-M-producing E. coli isolates indicate that CTX-M-producing strains were more often MDR than bacteria producing other types of ESBLs.…”

Detection of CTX-M-15 beta-lactamases in Enterobacteriaceae causing hospital- and community-acquired urinary tract infections as early as 2004, in Dar es Salaam, Tanzania

“…In recent years there has been an alarming increase in community acquired infections with ESBL-producing bacteria [5, 12, 18]. Spread of these strains in the community is a major concern to patient healthcare, since most display multidrug resistance, limiting outpatient treatment options.…”

“…Recent studies in Africa and Europe have found substantial increase in ESBL-producing Gram-negative bacteria causing community urinary tract infections, particularly harboring the bla CTX-M-15 allele [5–7]. Previously, studies in Tanzania have detected a substantial amount of ESBL-producing bacteria among the inpatients in intensive care and pediatric units in Tanzania [8, 9].…”