Genetic Structure Analysis of a Collection of Tunisian Durum Wheat Germplasm.

The Tunisian durum wheat germplasm includes modern cultivars and traditional varieties that are still cultivated in areas where elite cultivars or intensive cultivation systems are not suitable. Within the frame of a collection program of the National Gene Bank of Tunisia (NGBT), durum wheat germplasm was collected from different Tunisian agro-ecological zones. The collected samples were studied using simple sequence repeats (SSRs) markers to explore the genetic diversity and evaluate the genetic structure in Tunisian germplasm. The results demonstrated significant diversity in the Tunisian durum wheat germplasm, with clear differentiation between traditional varieties and modern cultivars. The population structure analysis allowed the identification of five subpopulations, two of which appear to be more strongly represented in germplasm collected in central and southern Tunisia, where environmental conditions at critical development phases of the plant are harsher. Moreover these subpopulations are underrepresented in modern varieties, suggesting that traits of adaptation useful for breeding more resilient varieties might be present in central and southern germplasm. Moreover, our results will support, the activity of in situ on farm conservation of Tunisian durum wheat germplasm started by the National Gene Bank of Tunisia along with the ex situ approach.

Bacteriological and therapeutic profile of diabetic foot infection: a prospective study of 100 patients.

BACKGROUND: Identifying the infecting bacterial flora is one of the main rules to be followed to ensure the success of antibiotherapy in the treatment of the infected diabetic foot. The aim of the work was to define the bacteriological profile of the bacteria causing the infection of the diabetic foot at the surgery unit B of Charles Nicolle's hospital in Tunis and determine the prognostic factors of this condition. METHODS: It was an open prospective study. It concerned 100 diabetic patients operated on for diabetic foot infection. All patients had bacteriological samples taken through deep scraping and swabing carried out in the operating room. RESULTS: The average age of patients was 59,5 ±11 years, with a sex-ratio of 2,4. The foot infection was represented in 82 % of cases by a wet gangrene. The enterobacteria were the most frequently isolated bacteria (73%), followed by streptococcus (10%), Staphylococcus aureus (9%). The rate of multidrug-resistant bacteria was of 9,5%. The empiric antibiotic therapy used (fusidic acid +amoxicillin/ clavulanic acid) was inactiveon 44,1% of the isolated bacteria. When we compared the group of patients with unfavourable development (who have been reoperated) and the group of patients with favourable development, we have found two poor prognosis factors : arteritis  (p=0,018 ; OR=23,7) and presence of multidrug-resistant bacteria (p=0,027 ; OR=5,8). CONCLUSION: The enterobacteria were the main bacteria causing the infection of diabetic foot. The prognostic factors found, arteritis and isolation of multidrug-resistant bacteria, outpoint the importance of multidisciplinary care.

Family cluster of Middle East respiratory syndrome coronavirus infections, Tunisia, 2013.

In 2013 in Tunisia, 3 persons in 1 family were infected with Middle East respiratory syndrome coronavirus (MERS-CoV). The index case-patient's respiratory tract samples were negative for MERS-CoV by reverse transcription PCR, but diagnosis was retrospectively confirmed by PCR of serum. Sequences clustered with those from Saudi Arabia and United Arab Emirates.

Loss and gain of N-linked glycosylation sites in globular head and stem of HA found in A/H3N2 flu fatal and severe cases during 2013 Tunisia flu seasonal survey.

Glycosylation on the globular head of the hemagglutinin (HA) protein of influenza virus acts as an important target for recognition and destruction of virus by innate immune proteins of the collectin family. In the current study, we have characterized the dynamic amino acid changes at N-linked glycosylation sites of full length sequences of HA genes of 5 A/H3N2 Tunisian strains isolates from mild, severe, and fatal cases. Compared to the reference strain, A/Perth/16/2009 substitutions in potential N-glycosylation sites were observed in 5 HA genes at five different positions (45, 124, 128, 144, and 145) generating the losses and gains of N-linked glycosylation sites. Also the mutation N145S was presented in the receptor-binding site of all segments analyzed. Point mutations in several positions in the gene encoding the H3 of Tunisian strains were shown to ablate a glycan attachment site and also loss of a potential glycosylation site. The relation between these mutations and virulence of influenza A/H3N2 virus needed to be verified in the further experiments.

Genetic diversity of HA1 domain of heammaglutinin gene of influenza A(H1N1)pdm09 in Tunisia.

We present major results concerning isolation and determination of the nucleotide sequence of hemagglutinin (HA1) of the pandemic (H1N1)pdm09 influenza viruses found in Tunisia. Amino acid analysis revealed minor amino acid changes in the antigenic or receptor-binding domains. We found mutations that were also present in 1918 pandemic virus, which includes S183P in 4 and S185T mutation in 19 of 27 viruses analyzed from 2011, while none of the 2009 viruses carried these mutations. Also two specific amino acid differences into N-glycosylation sites (N288T and N276H) were detected. The phylogenetic analysis revealed that the majority of the Tunisian isolates clustered with clade A/St. Petersburg/27/2011 viruses characterized by D97N and S185T mutations. However it also reveals a trend of 2010 strains to accumulate amino acid variation and form new phylogenetic clade with three specific amino acid substitutions: V47I, E172K and K308E.

Haemagglutinin D222G mutation found in a fatal case of pandemic (H1N1) flu in Tunisia.

Recently, the D222G substitution was observed in the HA of pandemic (H1N1) 2009 viruses isolated from fatal cases in several countries. We made a similar observation in one fatal case in Tunisia showing a D222G substitution in a virus isolate. The man was 47 years old and had no other subjacent pathologies or any known risk factors. He died after three days, suffering from severe respiratory symptoms of flu. The causal link of the D222G substitution in Tunisia with virulence must be verified. Further study is warranted to elucidate the intriguing relationship between the D222G substitution and severe disease. Constant molecular surveillance is important to monitor the pathogenicity of circulating strains and evaluate vaccine efficacy.

[Comparison of differents molecular methods for the detection of cytomegalovirus DNA in immunodepressed patients]. / Comparaison moléculaire de trois techniques de détection d'ADN du cytomégalovirus humain chez des immunodéprimés.

BACKGROUND: A Cytomegalovirus infection (HCMV) causes severe complications in immunosuppressed individuals (transplant recipients and AIDS patients). AIM: To detect the DNA of the HCMV by three molecular methods, and to identify the fastest method and most significant. METHODS: we tested 50 samples in order to detect the presence of the HCMV. This research was carried out by molecular Hybridization, the pp65 Antigenemia and PCR on the blood of the patients presenting an infection to CMV. RESULTS: Molecular hybridization is positive for 64%, Antigenemia is detected in 26 cases (50%) and the plasmatic PCR is positive in 13 cases (26%). These studies demonstrated that molecular hybridization permitted CMV detection of different biological liquid but Antigenemia and PCR techniques were used to determine of from leukocytes. Plasma-PCR and Hybridization assay presented the qualitatifs results. CONCLUSION: These studies indicate that there is a combining virological between molecular methods.

[Evaluating the therapeutic care of HIV infection in Tunisia]. / Evaluation de la prise en charge thérapeutique de l'infection par le VIH en Tunisie.

OBJECTIVE: Our aim is to determine different therapeutic response profiles in Tunisian HIV-1 infected patients, to identify those with therapeutic failure and to compare the results of the genotypic resistance test used in Tunisia (INNO LiPA Test) with those of automatic sequencing to evaluate its efficacy. METHODS: The retrospective survey concerns 392 infected patients enrolled from January 2001 to December 2006. Evaluation of HIV INNO LiPA test was performed by comparing these test results with those of automatic sequencing in 36 plasmatic samples for 13 infected patients with therapeutic failure. RESULTS: on the basis of the HIV viral load evolution, 57.55% of patients present a good therapeutic response and 42.44% a bad one. Patients with therapeutic failure require genotypic resistance test. A comparison of HIV INNO LiPA test and direct sequencing showed a strong concordance between the two tests results either for reverse transcriptase gene or protease gene. However, the results obtained by INNO LiPA test (8.79% of analysed codons ) and the limited number of analysed codons were the defaults of INNO LiPA technique. CONCLUSION: the contribution of INNO LiPA technique in the knowledge of the epidemiological HIV resistance profiles of virus strains of HIV infected individuals failing therapy was considerable. However, due to INNO LiPA technique limitations, sequence analysis must be considered a more complete assay for the monitoring of antiretroviral resistance of HIV infected patients.

Antimicrobial susceptibility and MLVA analysis of S. Typhimurium strains isolated from human and poultry samples in Tunisia.

INTRODUCTION: Salmonella enterica infections are a significant public health concern worldwide, being Salmonella Typhimurium one of the most prevalent serovars. Human salmonellosis is typically associated with the consumption of contaminated foods, such as poultry, eggs and processed meat. The extensive use of antimicrobials in humans and animals has led to an increase in multidrug resistance among Salmonella strains, becoming multidrug-resistant (MDR) strains a major public health concern. METHODOLOGY: This study was designed to investigate the antimicrobial susceptibility and the genotypic diversity of Salmonella Typhimurium strains isolated in Tunisia from human and poultry sources from 2009 to 2015. Fortyfive strains were analyzed by disk-diffusion test to determine the antimicrobial susceptibility. The presence of antimicrobial resistance genes was tested by PCR, and genotyping was performed using multiple-locus variable-number tandem repeats analysis (MLVA). RESULTS: About 50% of the strains were resistant to at least 3 antibiotics (multidrug-resistant strains, MDR). The most frequent resistance profile in clinical strains was AMP-TIC-TET-MIN-SXT (n = 7) and TET-MIN in poultry origin strains (n = 7). The MLVA typing grouped the strains in 2 main clusters. Cluster I was mostly formed by human isolates, whereas in cluster II both human and poultry isolates were grouped. Simpson's diversity index was 0.870 and 0.989 for antimicrobial resistance profiles and MLVA, respectively. CONCLUSIONS: Multiresistance is common in Salmonella Typhimurium isolated from human and poultry sources in Tunisia. The genotyping results suggest that some strains isolated from both sources may descend from a common subtype.

First report of extensively-drug-resistant Proteus mirabilis isolate carrying plasmid-mediated blaNDM-1 in a Tunisian intensive care unit.

Emergence of the New Delhi metallo-ß-lactamase (NDM-1), an Ambler class B metallo-ß-lactamase able to hydrolyse all ß-lactams except monobactams, constitutes a critical and increasingly important medical issue. The acquisition of blaNDM-1 is of particular concern for Proteus mirabilis, which is intrinsically resistant to tetracycline, tigecycline and colistin, as this will make clinical treatment extremely difficult. To the authors' knowledge, this is the first report of the blaNDM-1 gene in an extensively-drug-resistant P. mirabilis clinical isolate carrying plasmid-mediated resistance to carbapenems (blaNDM-1), cephalosporins (blaCMY-4), aminoglycosides (aph3 VIa and aph3 Ia) and fluoroquinolones (qnrA6).

Role of association of OmpK35 and OmpK36 alteration and blaESBL and/or blaAmpC genes in conferring carbapenem resistance among non-carbapenemase-producing Klebsiella pneumoniae.

In Klebsiella pneumoniae, loss of the two major outer membrane porins (OMPs) OmpK35 and OmpK36 confers resistance to carbapenems in strains producing extended-spectrum ß-lactamases (ESBLs) or plasmid-mediated AmpC-type ß-lactamases. This study investigated mechanisms responsible for carbapenem resistance in non-carbapenemase-producing K. pneumoniae (NCPK). All carbapenem-resistant Enterobacteriaceae (CRE) at Charles Nicolle Hospital (Tunis, Tunisia) were collected over a 6-year period (2010-2015). Among the 334 CRE strains collected, 44 (13.2%) were NCPK. MIC ranges for ertapenem, imipenem and meropenem were 1 to >32 mg/L, 0.125-8 mg/L and 0.125-32 mg/L, respectively. All strains showed a multidrug-resistant (MDR) phenotype and were negative for carbapenemase activity. None of the carbapenemase genes searched for were found. ESBL production was confirmed in all isolates except one [CTX-M-15 (n = 39) and SHV-5 (n = 4)]. Three isolates produce DHA-1 (associated with CTX-M-15 in two strains). Molecular fingerprints grouped the 44 NCPK isolates into seven clusters. In seven representative strains of these clusters, SDS-PAGE results showed that four isolates lacked the OmpK35 porin, one isolate lacked OmpK36 and two isolates lacked both OmpK35 and OmpK36. Sequencing of the corresponding porin genes showed amino acid insertions and deletions leading to early termination of translation, point mutations in the promoter region, or insertion sequences disrupting the gene coding sequence. Loss or deficiency of OMPs, coupled with ESBL and/or AmpC production, plays an important role in conferring carbapenem resistance in K. pneumoniae. Dissemination of these MDR bacteria in our hospital may create serious therapeutic problems in the future.

An Outbreak of NDM-1-Producing Klebsiella pneumoniae, Associated with OmpK35 and OmpK36 Porin Loss in Tunisia.

OBJECTIVES: To describe clinical and molecular characteristics of an outbreak due to metallo-ß-lactamases (MBLs) producing Klebsiella pneumoniae collected at Charles Nicolle Hospital of Tunis and to analyze the impact of outer membrane porin (OMP) loss on carbapenem resistance levels. METHODS: Between 2010 and 2015, 178 carbapenem-resistant Enterobacteriaceae were isolated. Screening for MBL production was performed using combined disk diffusion method, with imipenem and ethylene diamine tetraacetic acid (EDTA) as inhibitors. Resistance genes and virulence factors were identified by polymerase chain reaction (PCR) and sequencing. Genotyping was performed by pulsed-field gel electrophoresis and multilocus sequence typing. Genetic environment of carbapenemase genes was determined by PCR mapping. Conjugation assays were performed, and plasmids were assigned to incompatibility groups by PCR-based replicon typing. OMPs were profiled by sodium dodecyl sulfate-polyacrilamide gel electrophoresis, and porin genes were sequenced. RESULTS: Nineteen K. pneumoniae (10.6%) showing MBL activity were isolated from patients hospitalized on four different wards. NDM-1 was the only MBL identified, in association with blaOXA-48. All strains lacked at least one OMP, and carbapenem resistance levels were remarkably elevated in strains lacking OmpK35 and OmpK36. blaNDM-1 was located in IncFIA-type conjugative plasmid, with the same genetic context in all strains. The epidemiological diffusion of blaNDM-1 was due to two clones, one major clone belonging to sequence type (ST) 147 (n = 16) and the other clone belonging to ST307 (n = 3). CONCLUSIONS: This study describes an outbreak of NDM-1-producing K. pneumoniae strains, isolated from a Tunisian hospital, caused by two clones belonging to ST147 and ST307; and highlights the role of OMPs loss, in combination with ß-lactamase expression, in conferring high carbapenem resistance.

Identification of the CCR5-Delta32 HIV resistance allele and new mutations of the CCR5 gene in different Tunisian populations.

Polymorphisms in some chemokine receptor genes are associated with susceptibility to and progression of human immunodeficiency virus-1 (HIV-1) infection. Most mutations detected in the CC-chemokine receptor 5 (CCR5) gene are specific to different populations. In this study, we focused on polymorphisms of the CCR5 coding region in three healthy populations from Tunisia, corresponding to a cosmopolitan population from Tunis, and two isolated Berber populations. In addition to the CCR5-Delta32 deletion, eleven single nucleotide polymorphisms were detected. Some of these point mutations were associated with the same genotype and even the same haplotype. The (L55Q-C101X), I124, V131F, T143N, A159V, I237, T239A and G301R alleles have not been described previously, whereas the CCR5-Delta32, L55Q, A335V and Y339F variants have already been reported in the literature. The distribution and frequency of these variants were different among the three groups studied, a result in agreement with the mosaic genetic structure of the Tunisian population. To determine whether these alleles affect HIV-1 transmission, we compared allele frequencies between healthy and HIV-1 infected individuals from Tunis. The frequency of the CCR5-Delta32 variant was significantly different between the two groups, leading us to conclude that this mutation might confer protection against HIV infection in Tunisian populations.

Human herpesvirus-6 (HHV-6) DNA in plasma reflects the presence of infected blood cells rather than circulating viral particles.

BACKGROUND: The presence of HHV-6 DNA in plasma or serum is considered a good marker of active infection. However, it is ignored whether this DNA corresponds to virus particles produced by lymphoid tissue infection or virus-free DNA released from infected circulating blood cells. OBJECTIVES: To investigate whether HHV-6 DNA in whole plasma is nonencapsidated and its amount is correlated to cellular and human herpesvirus-7 (HHV-7) DNA loads in plasma subfractions as well as in corresponding peripheral blood mononuclear cells (PBMCs). STUDY DESIGN: Whole plasma samples from immunocompromised patients were submitted to a DNase-resistance test. Plasma samples from a second group of patients were split up into three subfractions: P1 (pellet of clarification), P2 (pellet of ultracentrifugation), and S (supernatant of ultracentrifugation). HHV-6, HHV-7, and cellular DNA loads were determined in each fraction and PBMCs using specific real-time PCR. RESULTS: Among 14 whole plasma samples, the majority of HHV-6 DNA detected was unprotected against DNase, i.e. nonencapsidated. The study of 35 other plasma samples revealed that cellular DNA was present in all subfractions from all samples whereas HHV-6 DNA was detected in 13 P1, 12 P2, 10 S fractions, and HHV-7 DNA in only one P1 fraction. Accordingly, median HHV-6 DNA load was significantly higher in P1 than in P2 and S fractions. The detection of HHV-6 DNA in plasma subfractions was statistically associated with a higher HHV-6 viral load in PBMCs (p

Comparison of pp65 antigenemia, quantitative PCR and DNA hybrid capture for detection of cytomegalovirus in transplant recipients and AIDS patients.

The cytomegalovirus (CMV) antigenemia assay has been used frequently for rapid diagnosis of CMV infection, and antigenemia threshold values are recommended for triggering preemptive therapy. Hybrid capture of CMV's DNA and quantitative polymerase chain reaction (qPCR) are increasingly being adopted for early detection of CMV. The performance of the antigenemia assay, qPCR in plasma and hybrid capture in leukocytes were compared in 110 immunocompromised patients (38 bone-marrow transplants, 50 renal transplants and 22 AIDS patients). The most sensitive test was hybrid capture for transplants, while antigenemia and the qPCR showed similar performance for patients with AIDS. QPCR and hybrid capture thresholds requiring antiviral therapy were calculated using a receiver-operating-characteristic curve for antigenemia values corresponding to 2 positive cells for bone-marrow transplants and to 10 positive cells for renal transplants and AIDS patients. These threshold values varied with the group of patients considered, with corresponding sensitivities higher than 86% and specificities higher than 76% for hybrid capture, and sensitivities higher than 61% and specificities higher than 75% for qPCR in plasma. Hybrid capture in leukocytes can substitute for antigenemia in the case of transplants, and qPCR in plasma can substitute for it in the case of AIDS patients.

Community fecal carriage of broad-spectrum cephalosporin-resistant Escherichia coli in Tunisian children.

The spread of extended spectrum ß-lactamases (ESBL) and plasmid mediated AmpC ß-lactamases (pAmpC) was evaluated in Escherichia coli strains collected from the intestinal microbiota of healthy children in Tunisia. The carriage rate of CTXRE. coli was 6.6% (7 of 105 samples) and one strain/sample was further characterized (7 isolates). These isolates harbored blaCTX-M-1 (n = 4), blaCTX-M-15 (n = 2), and blaCMY-2 gene (n = 1), which were usually located on FIB replicon type and carried class 1 integrons. The acc(6')-Ib-cr variant was identified in one isolate that harbored blaCTX-M-15. CTXRE. coli isolates were genetically unrelated and belonged to B1 (n = 3/ST155/ST398/ST58), D (n = 2/ST117/ST493), B2 (n = 1/ST127), and A (n = 1/ST746) phylogroups. Strain virulence scores varied from 3 to 12, and frequently harbored the pathogenicity island PAI IV536. The intestinal tract of healthy children constitute an important reservoir of ESBL producing E. coli. Thus, improvement of hygiene measures mainly in the school environment and rational use of antibiotics would be of great help in preventing selection and diffusion of resistant strains from intestinal microbiota.

Genetic Diversity of HIV-1 in Tunisia.

In this study, the genetic diversity of HIV-1 in Tunisia was analyzed. For this, 193 samples were collected in different regions of Tunisia between 2012 and 2015. A protease and reverse transcriptase fragment were amplified and sequenced. Phylogenetic analyses were performed through maximum likelihood and recombination was analyzed by bootscanning. Six HIV-1 subtypes (B, A1, G, D, C, and F2), 5 circulating recombinant forms (CRF02_AG, CRF25_cpx, CRF43_02G, CRF06_cpx, and CRF19_cpx), and 11 unique recombinant forms were identified. Subtype B (46.4%) and CRF02_AG (39.4%) were the predominant genetic forms. A group of 44 CRF02_AG sequences formed a distinct Tunisian cluster, which also included four viruses from western Europe. Nine viruses were closely related to isolates collected in other African or in European countries. In conclusion, a high HIV-1 genetic diversity is observed in Tunisia and the local spread of CRF02_AG is first documented in this country.

[Detection of DNA human cytomegalovirus of a molecular methods: hybrid capture DNA CMV by immunocompromised]. / Detection de l'adn du cytomegalovirus humain par hybridation moleculaire chez les immunodéprimés.

Human cytomegalovirus (HCMV), a member of the beta-virus herpes family, is a ubiquitous human pathogen. After a primary infection, HCMV establishes life latency. HCMV rarely causes symptomatic disease in an immunocompetent host, however, it is a major cause of infectious morbidity and mortality in immunocompromised individuals and developing fetuses. The HCMV genome consists of 240 kbp of double stranded DNA. Early diagnosis molecular of CMV infection is important. The objective of this study was to develop a molecular methods: Quantitative Hybrid capture for the detection of DNA CMV. We present results for 200 immunocompromised collected from 1999 to 2003 (122 men and 78 women, whom mean age was 35 years). Our results showed that 25% of women and 36% of men were positif for hybrid capture DNA CMV. This simple test (cold probe) provide quantitative and fast results. Also the efficacity of anti-CMV therapy can be followed. More over, in contrary with pp65-antigenemia assay and CMV PCR, this test can be managed on biopsy sample.

[Virological diagnosis and follow-up of HIV infection. State of the art and situation in Tunisia]. / Diagnostic et suivi virologique de l'infection par le VIH : etat actuel et situation en Tunisie.

Human immunodeficiency virus (HIV) is a retrovirus infecting approximatively 40 million people worldwide. HIV is characterized by a great variability with epidemiological, diagnostic and therapeutic implications. The course of infection goes through three stages (acute infection, clinical latency and AIDS) with the evolution of virological markers (anti-HIV antibodies, p24 antigenemia, plasma RNA and proviral DNA). Direct virological diagnosis is mainly based on molecular tools allowing viral genome detection and amplification with specific primers and nucleic probes besides p24 antigenemia detection, and more rarely viral culture. Antigenic properties of viral proteins elicit in infected patients antibody synthesis, which is detected using serology (ELISA and Western blot tests). The follow-up of infected patients is carried out with plasma HIV-1 RNA quantitation and phenotypic or genotypic characterization of variant isolates. Virological tests are prescribed according to clinical presentation (screening, acute infection, newborn from HIV-infected mother). Most of these virological tools are available in Tunisia, allowing both diagnosis of HIV infection and monitoring of infected individuals. Regarding diagnostic tests indication and interpretation, multidisciplinary concertation is hopeful in order to optimize patient management.

High Prevalence of Gut Microbiota Colonization with Broad-Spectrum Cephalosporin Resistant Enterobacteriaceae in a Tunisian Intensive Care Unit.

Healthcare-associated infections due to cefotaxime-resistant (CTX-R) Enterobacteriaceae have become a major public health threat, especially in intensive care units (ICUs). Often acquired nosocomially, CTX-R Enterobacteriaceae can be introduced initially by patients at admission. This study aimed to determine the prevalence and genetic characteristics of CTX-R Enterobacteriaceae-intestinal carriage in ICU patients, to evaluate the rate of acquisition of these organisms during hospitalization, and to explore some of the associated risk factors for both carriage and acquisition. Between December 2014 and February 2015, the 63 patients admitted in the ICU of Charles Nicolle hospital were screened for rectal CTX-R Enterobacteriaceae colonization at admission and once weekly thereafter to identify acquisition. CTX-R Enterobacteriaceae fecal carriage rate was 20.63% (13/63) at admission. Among the 50 non-carriers, 35 were resampled during their hospitalization and the acquisition rate was 42.85% (15/35). Overall, 35 CTX-R Enterobacteriaceae isolates were collected from 28 patients (25 Klebsiella pneumoniae, seven Escherichia coli, and three Enterobacter cloacae strains). Seven patients were simultaneously colonized with two CTX-R Enterobacteriaceae isolates. CTX-M-15 was detected in most of the CTX-R Enterobacteriaceae isolates (30/35, 88.23%). Three strains co-produced CMY-4 and 22 strains were carbapenem-resistant and co-produced a carbapenemase [OXA-48 (n = 13) or NDM-1 (n = 6)]. Molecular typing of K. pneumoniae strains, revealed eight Pulsed field gel electrophoresis (PFGE) patterns and four sequence types (ST) [ST101, ST147, ST429, and ST336]. However, E. coli isolates were genetically unrelated and belonged to A (n = 2), B1 (n = 2) and B2 (n = 3) phylogenetic groups and to ST131 (two strains), ST572 (two strains), ST615 (one strain) and ST617 (one strain). Five colonized patients were infected by CTX-R Enterobacteriaceae (four with the same strain identified from their rectal swab and one with a different strain). Whether imported or acquired during the stay in the ICU, colonization by CTX-R Enterobacteriaceae is a major risk factor for the occurrence of serious nosocomial infections. Their systematic screening in fecal carriage is mandatory to prevent the spread of these multidrug resistant bacteria.