title: Low antibiotic resistance rates and high genetic heterogeneity of Escherichia coli isolates from urinary tract infections of diabetic patients in Tunisia.
abstract: Antimicrobial resistance phenotypes, tetracycline, sulphonamide resistance genes, and integrons were analysed in 48 Escherichia coli isolates recovered from urine cultures of diabetic patients in Tunisia. Twenty-one were susceptible to all antibiotics tested. High rates of resistance were observed for amoxicillin (39.5%), trimethoprim-sulphamethoxazole (33.3%), sulphonamide (33.3%), and tetracycline (31.2%). Resistance to imipenem was not detected, and ESBL producing isolates were not recovered. Our analysis assigned 26, 13, 3, and 5 isolates to phylogroups A, B1, B2, and D, respectively. It is worthy to note that all the resistant isolates belonged to phylogroups A (15 isolates) and B1 (12 isolates), while for the 21 susceptible isolates, phylogroups A, B1, B2, and D were found in 11, 2, 3, and 5 isolates, respectively. Among 15 tetracycline-resistant isolates, the tetA and tetB genes were detected in three and four isolates, respectively. Among 17 sulphonamide resistant isolates, 12, 3, and 1 isolates harboured sul1, sul2, and sul3, respectively. sul1 and sul2 genes occurred simultaneously in three isolates. Integrons were detected in 11 isolates. Ten isolates harboured the class 1 integron and three the class 2 integron. The variable regions (VRs) of the class 1 integrons were analysed in the 10 in1-positive isolates, and the following gene cassette arrangements were detected: dfrA12-orfF-aadA2-cmIA1-aadA1-qacH-IS440-sul3 (one isolate), dfrA15-aadA1 (three isolates), dfrA5 (one isolate), dfrA17- aadA5 (one isolate), dfrA1-aadA1 (one isolate), and dfrA14 (one isolate). The VR of class 2 integron was analysed in the in2-positive isolates, and only one gene cassette arrangement was detected, dfrA1-sat-aadA1. Pulsed-field gel electrophoresis (PFGE) analysis of resistant isolates showed that all were unrelated. Our results highlight the moderate antibiotic resistance in the clinical isolates as well as their heterogeneous genetic background.
authors.affiliation: a Institute of Veterinary Research of Tunisia , Tunis , Tunisia.|c Laboratory of the National Bone Marrow Transplantation Centre , Tunis , Tunisia.
authors.forename: Debbichi
authors.initials: D
authors.lastname: Najwa
authors.affiliation: a Institute of Veterinary Research of Tunisia , Tunis , Tunisia.
authors.forename: Abbassi Mohamed
authors.initials: AM
authors.lastname: Salah
authors.affiliation: b Área de Microbiología Molecular, Centro de Investigación Biomédica de La Rioja (CIBIR) , Logroño , Spain.
authors.forename: Sáenz
authors.initials: S
authors.lastname: Yolanda
authors.affiliation: a Institute of Veterinary Research of Tunisia , Tunis , Tunisia.
authors.forename: Khemiri
authors.initials: K
authors.lastname: Monia
authors.affiliation: c Laboratory of the National Bone Marrow Transplantation Centre , Tunis , Tunisia.
authors.forename: Majouri
authors.initials: M
authors.lastname: Dorsaf
authors.affiliation: d National Institute of Nutrition and Food Technology of Tunisia , Tunis , Tunisia.
authors.forename: Ben Rayena
authors.initials: BR
authors.lastname: Chiheb
authors.affiliation: a Institute of Veterinary Research of Tunisia , Tunis , Tunisia.
authors.forename: Ben Salem
authors.initials: BS
authors.lastname: Rakia
authors.affiliation: a Institute of Veterinary Research of Tunisia , Tunis , Tunisia.
authors.forename: Kilani
authors.initials: K
authors.lastname: Hajer
authors.affiliation: c Laboratory of the National Bone Marrow Transplantation Centre , Tunis , Tunisia.
authors.forename: Ben Hassen
authors.initials: BH
authors.lastname: Assia
authors.affiliation: e National School of Veterinary Medicine of Sidi Thabet (ENMV) Sidi Thabet , Tunisia.
authors.forename: Hammami
authors.initials: H
authors.lastname: Salah
mesh_terms: D048909:Diabetes Complications / Q000382:microbiology*; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000145:classification / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000382:microbiology*; D018740:Genetic Heterogeneity; D006801:Humans; D032023:Integrons; D014416:Tunisia; D014552:Urinary Tract Infections / Q000382:microbiology*
keywords: Diabetic patients; Escherichia coli; Genetic heterogeneity; Integrons