Genomic epidemiology of carbapenemase-producing Gram-negative bacteria at the human-animal-environment interface in Djibouti city, Djibouti.

The emergence of carbapenem resistance is a major public health threat in sub-Saharan Africa but remains poorly understood, particularly at the human-animal-environment interface. This study provides the first One Health-based study on the epidemiology of Carbapenemase-Producing Gram-Negative Bacteria (CP-GNB) in Djibouti City, Djibouti, East Africa. In total, 800 community urine samples and 500 hospital specimens from humans, 270 livestock fecal samples, 60 fish samples, and 20 water samples were collected and tested for carbapenem resistance. The overall estimated CP-GNB prevalence was 1.9 % (32/1650 samples) and specifically concerned 0.3 % of community urine samples, 2.8 % of clinical specimens, 2.6 % of livestock fecal samples, 11.7 % of fish samples, and 10 % of water samples. The 32 CP-GNB included 19 Escherichia coli, seven Acinetobacter baumannii, five Klebsiella pneumoniae, and one Proteus mirabilis isolate. Short-read (Illumina) and long-read (Nanopore) genome sequencing revealed that carbapenem resistance was mainly associated with chromosomal carriage of blaNDM-1, blaOXA-23, blaOXA-48, blaOXA-66, and blaOXA-69 in A. baumannii, and with plasmid carriage in Enterobacterales (blaNDM-1 and blaOXA-181 in E. coli, blaNDM-1, blaNDM-5 and blaOXA-48 in K. pneumoniae, and blaNDM-1 in P. mirabilis). Moreover, 17/32 CP-GNB isolates belonged to three epidemic clones: (1) A. baumannii sequence type (ST) 1697,2535 that showed a distribution pattern consistent with intra- and inter-hospital dissemination; (2) E. coli ST10 that circulated at the human-animal-environment interface; and (3) K. pneumoniae ST147 that circulated at the human-environment interface. Horizontal exchanges probably contributed to carbapenem resistance dissemination in the city, especially the blaOXA-181-carrying ColKP3-IncX3 hybrid plasmid that was found in E. coli isolates belonging to different STs. Our study highlights that despite a relatively low CP-GNB prevalence in Djibouti City, plasmids harboring carbapenem resistance circulate in humans, animals and environment. Our findings stress the need to implement preventive and control measures for reducing the circulation of this potentially emerging public health threat.

In vivo emergence of a still uncommon resistance to fidaxomicin in the urgent antimicrobial resistance threat Clostridioides difficile.

BACKGROUND: Fidaxomicin is a first-line treatment for Clostridioides difficile infections (CDIs). Fidaxomicin resistance has rarely been reported in this urgent antimicrobial resistance threat as defined by the CDC. OBJECTIVES: To report a case of fidaxomicin-resistant C. difficile isolation in a patient treated by fidaxomicin, characterize the genetic determinant for resistance and the consequences on pathophysiological traits, and review the literature. PATIENT AND METHODS: A 38-year-old male patient with several risk factors for CDI experienced three episodes of hospital-acquired CDI and received fidaxomicin for the first episode. The successive isolates were subjected to phenotypic characterization (antimicrobial susceptibility, growth, sporulation ability and toxin production) and WGS analysis to evaluate clonality and modifications associated with resistance. RESULTS: Resistance to fidaxomicin arose in isolates from the recurrences of CDI (MIC: 16 mg/L). WGS analysis showed a close genetic link between strains suggestive of relapses in this patient. A T3428G mutation in the rpoB gene might be associated with fidaxomicin resistance. The resistance was associated with defects in growth, sporulation and production of toxins. A review of the literature found only three previous fidaxomicin-resistant C. difficile clinical strains. CONCLUSIONS: Although rarely reported, resistance to fidaxomicin may quickly emerge in vivo after a single course of treatment. This observation supports the need for prospective surveillance of the susceptibility of C. difficile to treatment antibiotics. However, the clinical relevance of fidaxomicin resistance still needs to be elucidated, particularly due to its apparent rareness and associated fitness cost.

Prevalence and Phenotypic and Molecular Characterization of Carbapenemase-Producing Gram-Negative Bacteria in Gabon.

Data collection and monitoring of carbapenemase-producing (CP) Gram-negative bacteria (GNB) are often limited. This study determined CP-GNB prevalence in Gabon and the genetic origins of the resistance genes. From January 2016 to March 2018, 869 clinically significant GNB isolates from inpatients and outpatients, and 19 fecal samples (inpatients) were analyzed in the main hospitals of Gabon. Fecal samples were screened using ChromID® CARBA SMART selective chromogenic medium biplates. Species were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Antibiotic susceptibility was tested using the disk diffusion method on Müller-Hinton agar, and resistance genes were assessed by multiplex polymerase chain reaction and sequencing. Overall, 1.61% of clinical isolates (14 of 869) and 5.26% of fecal samples (1 of 19) were CP-GNB. The CP-GNB rate was higher among inpatients (2.98%) than outpatients (0.33%), in intensive care units (28.57%, 4 of 14), and in urine samples (35.71%, 5 of 14). The most common CP-GNB were Klebsiella pneumoniae (53.33%) and Acinetobacter baumannii (26.67%). blaOXA-48 was the predominant carbapenemase-encoding gene (40%), followed by blaNDM-5 (33.33%). The A. baumannii multilocus sequence types ST2 and ST78, Enterobacter cloacae ST78, Escherichia coli ST2, and K. pneumonia ST48 and ST147 were found. These data indicate that CP bacteria are present in clinical and carriage samples. Preventive measures are needed to avoid the spread of resistance genes.

Multidrug-Resistant Enterobacterales in Community-Acquired Urinary Tract Infections in Djibouti, Republic of Djibouti.

The emergence and spread of multidrug resistant Enterobacterales (MDR-E) are a global public health issue. This problem also concerns urinary tract infections (UTI), which are the second most frequent infections after respiratory infections. The objective of this study was to determine MDR-E frequency and to characterize MDR-E isolates from patients with community-acquired UTIs in Djibouti, Republic of Djibouti. From 800 clinical urinary samples collected at the Mer Rouge Laboratory, Djibouti, from January to July 2019, 142 were identified as Enterobacterales (age range of the 142 patients mean age is 42 years.) Mass spectrometry analysis of these isolates identified 117 Escherichia coli, 14 Klebsiella pneumoniae, 2 Proteus mirabilis, 4 Enterobacter spp., 4 Providencia stuartii and 1 Franconibacter helveticus. Antibiotic susceptibility testing (disk diffusion method) of these 142 isolates detected 68 MDR-E (68/142 = 48%): 65 extended-spectrum bêta lactamase- (ESBL), 2 carbapenemase- (one also ESBL), and 1 cephalosporinase-producer. Multiplex PCR and sequencing showed that the 65 ESBL-producing isolates carried genes encoding CTX-M enzymes (CTX-M-15 in 97% and CTX-M-9 in 3% of isolates). Two isolates harboured a gene encoding the OXA-48-like carbapenemase, and one the gene encoding the AmpC CMY-2 cephalosporinase. Genes implicated in resistance to quinolones (qnrB, aac (6')-Ib-cr, qnrD, oqxA and B) also were detected. Among the E. coli phylogroups, B2 was the most common phylogenetic group (21% of MDR-E isolates and 26% of non-MDR-E isolates), followed by A (14% and 12%), B1 (9% and 7%), D (3% and 3%), F (3% and 3%) and E (2% and 2%). This study highlights the high frequency of ESBL producers and the emergence of carbapenemase-producers among Enterobacterales causing community-acquired UTIs in Djibouti.

Antimicrobial Resistance in Enterobacterales Recovered from Urinary Tract Infections in France.

In the context of increasing antimicrobial resistance in Enterobacterales, the management of these UTIs has become challenging. We retrospectively assess the prevalence of antimicrobial resistance in Enterobacterales isolates recovered from urinary tract samples in France, between 1 September 2017, to 31 August 2018. Twenty-six French clinical laboratories provided the susceptibility of 134,162 Enterobacterales isolates to 17 antimicrobials. The most frequent species were E. coli (72.0%), Klebsiella pneumoniae (9.7%), Proteus mirabilis (5.8%), and Enterobacter cloacae complex (2.9%). The overall rate of ESBL-producing Enterobacterales was 6.7%, and ranged from 1.0% in P. mirabilis to 19.5% in K. pneumoniae, and from 3.1% in outpatients to 13.6% in long-term care facilities. Overall, 4.1%, 9.3% and 10.5% of the isolates were resistant to cefoxitin, temocillin and pivmecillinam. Cotrimoxazole was the less active compound with 23.4% resistance. Conversely, 4.4%, 12.9%, and 14.3% of the strains were resistant to fosfomycin, nitrofurantoin, and ciprofloxacin. However, less than 1% of E. coli was resistant to fosfomycin and nitrofurantoin. We identified several trends in antibiotics resistances among Enterobacterales isolates recovered from the urinary tract samples in France. Carbapenem-sparing drugs, such as temocillin, mecillinam, fosfomycin, cefoxitin, and nitrofurantoin, remained highly active, including towards ESBL-E.

Epidemiology and prevalence of extended-spectrum ß-lactamase- and carbapenemase-producing Enterobacteriaceae in humans, animals and the environment in West and Central Africa.

Extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-E) and carbapenemase-producing Enterobacteriaceae (CPE) are widespread. Here we used the 'One Health' approach to determine knowledge gaps on ESBL-E and CPE in West and Central Africa. We searched all articles on ESBL-E and CPE in these African regions published in PubMed, African Journals Online and Google Scholar from 2000 onwards. Among the 1201 articles retrieved, we selected 165 studies (West Africa, 118; Central Africa, 47) with data from 22 of the 26 West and Central Africa countries. Regarding the settings, 136 articles focused only on humans (carriage and/or infection), 6 articles on humans and animals, 13 on animals, 1 on humans and the environment, 8 on the environment and 1 on humans, animals and environments. ESBL-E prevalence ranged from 11-72% in humans and 7-79% in aquatic environments (wastewater). In animals, ESBL-E prevalence hugely varied: 0% in cattle, 11-36% in chickens, 20% in rats, 21-71% in pigs and 32-75% in dogs. The blaCTX-M-15 gene was the predominant ESBL-encoding gene and was associated with plasmids of incompatibility groups F, H, K, Y, N, I1 and R. CPE were studied only in humans. Class B metallo-ß-lactamases (NDM) and class D oxacillinases (OXA-48 and OXA-181) were the most common carbapenemases. Our results show major knowledge gaps, particularly on ESBL and CPE in animals and the environment, that might limit antimicrobial resistance management in these regions. The results also emphasise the urgent need to improve active surveillance programmes in each country and to support antimicrobial stewardship.

Prevalence and Molecular Characterization of Extended Spectrum ß-Lactamase, Plasmid-Mediated Quinolone Resistance, and Carbapenemase-Producing Gram-Negative Bacilli in Burkina Faso.

The spreading of carbapenemase-producing gram-negative bacilli (GNB) must be considered as an "urgent" threat. The aim of this study was to determine the prevalence of extended spectrum ß-lactamase (ESBL), plasmid-mediated quinolone resistance (PMQR), and carbapenemase-producing GNB and to characterize the supporting genes in GNB specimens isolated from patients and healthy volunteers in Burkina Faso. From April to June 2016, carbapenemase-producing GNB screening was performed in 1,230 consecutive clinical specimens, and 158 fecal samples from inpatients and healthy volunteers without digestive pathology at Souro Sanou University Hospital, Bobo Dioulasso. Strains were identified by matrix-assisted laser desorption ionization-time of flight and antimicrobial susceptibility was tested with the disk diffusion method on Müller-Hinton agar. The presence of carbapenemase, ESBL, and PMQR genes was assessed by multiplex PCR. The molecular epidemiological study was performed using multilocus sequence typing analysis. From the 1,230 clinical samples, 443 GNB strains were isolated among which 4 (0.9%) were carbapenemase-producing isolates (Escherichia coli, n = 1; Acinetobacter baumannii, n = 3). Among the 158 fecal samples tested for carbapenemase-producing Enterobacteriaceae carriage, 13 (8.2%) were carbapenemase-producing isolates (E. coli, n = 4; Klebsiella pneumoniae, n = 6; A. baumannii, n = 2; Acinetobacter nosocomialis, n = 1; Acinetobacter bereziniae, n = 1). The strains from the two groups were resistant to broad-spectrum cephalosporins (100% for both), gentamicin (100% and 64.3%), levofloxacin (100% and 85.7%), and to amikacin (0% and 7.1%). The carbapenemase-encoding genes blaNDM-1, blaOxa-58, blaOxa-181, and blaVIM-2 were detected in clinical and in fecal samples. The majority (10/11) of the enterobacterial strains carried also blaCTX-M-15. The majority of the strains belonged to ST692 for E. coli, to ST147 for K. pneumoniae and to ST2 for A. baumannii. This study confirms the presence of carbapenemase-producing GNB in samples from patients and healthy volunteers. More effective active surveillance activities are needed.

Epidemiology and microbiological features of anaerobic bacteremia in two French University hospitals.

Bacteremia implicating anaerobic bacteria (BIAB) represents 2-6% of all episodes of bacteremia and is associated with high mortality. In this retrospective study from June 2015 to December 2016, we compared BIAB frequency in two hospital centers in Montpellier (France): Montpellier university hospital (MUH) and a center specialized in cancer (ICM). Among the 2465 microbiologically relevant episodes of bacteremia, we identified 144 (5.8%) in which anaerobic bacteria were implicated. BIAB frequency was higher at ICM than MUH (10.4%, vs. 4.9%, p < 0.01). Poly-microbial bacteremia was more frequent among the BIAB episodes (31.9% vs. 11.0% for aerobic-only bacteremia, p < 0.01). Bacteroides and Clostridium were the most frequently identified genera of anaerobic bacteria (64 and 18 episodes, respectively), with the B. fragilis group (BFG) involved in 68/144 episodes. We could perform antibiotic susceptibility typing in 106 of the 144 anaerobic isolates, including 67 BFG isolates. All isolates but one were susceptible to metronidazole. In the BFG, sporadic resistant or intermediate results were found for amoxicillin-clavulanate (5/67), piperacillin-tazobactam (2/67) and imipenem (1/67). BFG isolates were susceptible also to cefoxitin (90.8%), rifampicin (97.0%) and tigecyclin (91.0%). Multidrug resistance in this group (7 isolates) was mostly due to acquired resistance to moxifloxacin, clindamycin and tigecyclin. This study shows that BIAB frequency can vary among hospitals and services. They should especially be taken into account in centers specialized in cancer treatment. However, the implicated bacteria remain frequently susceptible to the most used antibiotics used against anaerobic bacteria, although resistance does exist.

[Criterium pencil mines as an alternative to platinum rods (Inoclic) in achievement of the antibiogram in agar medium for countries with limited resources?] / Les mines de crayon pour critérium comme alternative aux tiges de platine (Inoclic) dans la réalisation de l'antibiogramme en milieu gélosé pour les pays à ressources limitées ?

The realization of the antibiotic susceptibility test in agar is the routine bacteriological examination for the determination and monitoring of bacterial susceptibility to antibiotics. In this study, we report the comparative results between pencil leads for criterium, as an alternative to platinum rods in the realization of the antibiotic susceptibility test. METHODOLOGY: Experimental study evaluating the comparability of the results between Criterium and Inoclic mines (by counting bacterial cells on agar after 5 successive dilutions of reason 10 from a bacterial suspension obtained after piercing through a colony; by measuring the inhibition diameters of 4 ATCC reference bacterial strains on an antibiogram in an agar medium) and evaluating the sterility of the criterium mines by culturing them on enriched broth (heart - brain type). RESULTS: 42 bacterial strains were used for bacterial cell counting. The results were of the same order of magnitude (107 CFU/mL) between Inoclic and criterium mines, for all strains and at all dilutions. The antibiotic susceptibility tests performed for the 4 reference strains by the Inoclics and criterium mines all complied (100%) with the expected limits for determining their sensitivity profile to the antibiotics tested. Compared to the bacterial growth inhibition diameters on antibiotic susceptibility tests, no intra-operator variability was observed, while significant inter-operator variability (both with Inoclic and 0.5 mm criterium mines) was observed with some strains and for inhibition diameters greater than 10 mm. The enriched broth cultures (BCC) and their subculture carried out on 10 criterium mines from 5 different batches were negative. CONCLUSION: Criterium mines seem to be a serious and less expensive alternative to Inoclic for the realization of antibiotic susceptibility testing in our resource-limited countries.

Comparing identification of clinically relevant Prevotella species by VITEK MS and MALDI biotyper.

In this multicenter study, we aimed to evaluate the performance of MALDI Biotyper and VITEK MS, for identification of Prevotella species. Three hundred and fourteen clinical isolates, collected in eight European countries between January 2014 and April 2016, were identified at the collecting sites by MALDI Biotyper (versions 3.0 and 3.1) and then reidentified by VITEK MS (version 3.0) in the central laboratory. 16S rRNA gene sequencing was used as a standard method. According to sequence analysis, the 314 Prevotella strains belonged to 19 species. MALDI Biotyper correctly identified 281 (89.5%) isolates to the species level and 33 (10.5%) only at the genus level. VITEK MS correctly identified 253 (80.6%) isolates at the species level and 276 (87.9%) isolates at the genus level. Thirty-three isolates belonging to P. bergensis, P. conceptionensis, P. corporis, P. histicola, and P. nanciensis, unavailable in the VITEK MS 3.0 database, were resulted in genus level or no identification. Six Prevotella strains, belonged to P. veroralis, P. timonensis, and P. conceptionensis not represented in the MALDI Biotyper system database, were misidentified at the genus level. In conclusion, both VITEK MS and MALDI Biotyper provided reliable and rapid identification. However, the permanent extension of the databases is needed.

Fecal carriage of extended-spectrum ß-lactamase-producing Enterobacteriaceae in hospital and community settings in Chad.

Background: Fecal carriage of extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-PE) remains poorly documented in Africa. The objective of this study was to determine the prevalence of ESBL-PE fecal carriage in Chad. Methods: In total, 200 fresh stool samples were collected from 100 healthy community volunteers and 100 hospitalized patients from January to March 2017. After screening using ESBL-selective agar plates and species identification by MALDI-TOF mass spectrometry, antibiotic susceptibility was tested using the disk diffusion method, and ESBL production confirmed with the double-disc synergy test. The different ESBL genes in potential ESBL-producing isolates were detected by PCR and double stranded DNA sequencing. Escherichia coli phylogenetic groups were determined using a PCR-based method. Results: ESBL-PE fecal carriage prevalence was 44.5% (51% among hospitalized patients vs 38% among healthy volunteers; p < 0.05). ESBL-producing isolates were mostly Escherichia coli (64/89) and Klebsiella pneumoniae (16/89). PCR and sequencing showed that 98.8% (87/89) of ESBL-PE harbored blaCTX-M genes: blaCTX-M-15 in 94.25% (82/87) and blaCTX-M-14 in 5.75% (5/87). Phylogroup determination by quadruplex PCR indicated that ESBL-producing E. coli isolates belonged to group A (n = 17; 27%), C (n = 17; 27%), B2 (n = 9; 14%), B1 (n = 8; 13%), D (n = 8; 13%), E (n = 1; 1.6%), and F (n = 1; 1.6%). The ST131 clone was identified in 100% (9/9) of E. coli B2 strains. Conclusions: The high fecal carriage rate of ESBL-PE associated with CTX-M-15 in hospital and community settings of Chad highlights the risk for resistance transmission between non-pathogenic and pathogenic bacteria.

Spread of NDM-5 and OXA-181 Carbapenemase-Producing Escherichia coli in Chad.

We detected for the first time blaNDM-5 and blaOXA-181 in Escherichia coli isolates from hospitalized patients and healthy volunteers in Chad. These resistance genes were located on IncX3 and IncF plasmids. Despite the large diversity of E. coli clones, the identified resistant intestinal isolates belonged mainly to the same sequence type.

Cervical anaerobic vertebral osteomyelitis following surgical tracheotomy: a case report.

BACKGROUND: We report a rare case of anaerobic vertebral osteomyelitis associated with surgical tracheotomy which has never been reported to the best of our knowledge. CASE PRESENTATION: A healthy 39-year-old man was admitted to intensive care for a severe brain trauma injury where a surgical tracheotomy was performed. He was discharged to a rehabilitation centre after 54 days hospital stay. During rehabilitation, he developed progressive and febrile tetraplegia associated with cervical pain, requiring an intensive care readmission. A polymicrobial anaerobic bloodstream infection was revealed and magnetic resonance imaging diagnosed cervical vertebral osteomyelitis. Both the type of anaerobic micro-organisms found and the timing of the symptoms strongly suggest that the surgical tracheotomy was responsible for this rare case of cervical vertebral osteomyelitis. The patient was successfully treated by a prolonged antimicrobial therapy and by surgical laminectomy. CONCLUSIONS: Tracheotomy may generate anaerobic bacteraemia and related osteomyelitis in the specific setting of severe trauma patients. Clinicians should consider anaerobic vertebral osteomyelitis when they are confronted with a febrile tetraplegia after tracheotomy.

Assessment of the In Vitro Activities of Ceftolozane/Tazobactam and Ceftazidime/Avibactam in a Collection of Beta-Lactam-Resistant Enterobacteriaceae and Pseudomonas aeruginosa Clinical Isolates at Montpellier University Hospital, France.

Objective: To assess in vitro ceftolozane/tazobactam (C/T) and ceftazidime/avibactam (CZA) activity in beta-lactam-resistant Enterobacteriaceae and Pseudomonas aeruginosa clinical isolates from major carbapenem-using Departments at Montpellier University Hospital, France. Materials and Methods: We tested third-generation cephalosporin-resistant Enterobacteriaceae (by production of extended spectrum ß-lactamase or other mechanisms, mainly AmpC beta-lactamases) and ceftazidime- and/or carbapenem-resistant P. aeruginosa strains isolated from clinical samples of patients hospitalized from January 2017 to May 2017 and August 2016 to July 2017, respectively. We also included all OXA-48 beta-lactamase-producing Enterobacteriaceae strains isolated in the whole hospital from October 2015 to May 2017. We used the 2017 European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines for minimal inhibitory concentration interpretation. Results: Among the 62 cephalosporin-resistant Enterobacteriaceae strains, 60 (97%) were susceptible to CZA and 34 (65%) to C/T. The two CZA-resistant Klebsiella pneumoniae isolates produced (i) NDM-carbapenemase and extended-spectrum beta-lactamase (ESBL) and (ii) ESBL CTXM-15 and OXA-1 associated with impermeability. Moreover, 31 of the 42 P. aeruginosa strains (74%) were susceptible to CZA and 37 (88%) to C/T. Finally, 26/27 (96%) of OXA-48 beta-lactamase-producing Enterobacteriaceae were susceptible to CZA and 8/27 (30%) to C/T. Conclusions: At our hospital, CZA and C/T offer a carbapenem-sparing alternative for resistant gram-negative pathogens and could be a salvage therapy for carbapenem-resistant pathogens.

Whole-Genome Sequences of a Cluster of 14 Unidentified Related Veillonella sp. Strains from Human Clinical Samples and Type Strains of 3 Veillonella Validated Species.

We report 17 draft genomes for 14 unidentified Veillonella sp. strains closely related in 16S rRNA gene-based phylogeny and type strains of 3 Veillonella species with the aims of deciphering relationships between related species, evaluating the accuracy of current thresholds for species delineation, and robustly describing new species in the genus.

High prevalence and characterization of extended-spectrum ß-lactamase producing Enterobacteriaceae in Chadian hospitals.

BACKGROUND: Extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-PE) represent a major problem in the management of nosocomial infections. However, ESBL-PE are not systematically monitored in African countries. The aim of this study was to determine ESBL-PE prevalence in patients from three hospitals in N'Djamena, the capital city of Chad, and to characterize the genetic origin of the observed resistance. METHODS: From January to March 2017, 313 non-duplicate isolates were recovered from various clinical specimens obtained from 1713 patients in the three main hospitals of N'Djamena. Bacterial species were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Susceptibility to 28 antibiotics was tested using the disk diffusion method on Müller-Hinton agar, and ESBL production was confirmed with the double-disc synergy test. The most prevalent ESBL genes associated with the observed resistance were detected using multiplex PCR followed by double-stranded DNA sequencing. RESULTS: Among the 313 isolates, 197 belonged to the Enterobacteriaceae family. The overall ESBL-PE prevalence was 47.72% (n = 94/197), with a higher rate among inpatients compared with outpatients (54.13% vs. 34.37%). ESBL-PE prevalence was highest in older patients (≥60 years of age). E. coli was the most common ESBL-producer organism (63.8%), followed by K. pneumoniae (21.2%). ESBL-PE were mainly found in urine samples (75%). The CTX-M-1 group was dominant (96.7% of the 94 ESBL-PE isolates, CTX-M-15 enzyme), followed by the CTX-M-9 group (4.1%). 86% of resistant isolates harbored more than one ESBL-encoding gene. ESBL production was also associated with the highest levels of resistance to non-ß-lactam drugs. CONCLUSIONS: The prevalence of ESBL-PE harboring resistant genes encoding ESBLs of the CTX-M-1 group was high (48%) among clinical isolates of three main hospitals in Chad, suggesting an alarming spread of ESBL-PE among patients.

High Prevalence of Multidrug-Resistant Escherichia coli in Urine Samples from Inpatients and Outpatients at a Tertiary Care Hospital in Sétif, Algeria.

The worldwide dissemination of multidrug-resistant (MDR) Enterobacteriaceae is a major public health issue. The aim of this study was to investigate the prevalence of MDR Escherichia coli (MDR-EC) isolates, in inpatients/outpatients with urinary tract infections at Sétif University Hospital (Algeria). Bacterial cultures were obtained from 426 of the 3,944 urine samples collected from January 2015 to February 2017. Among these cultures, 215 E. coli isolates were identified by mass spectrometry, and 38 (17.7%) were MDR-EC (disk diffusion method): 36 produced only extended-spectrum ß-lactamases (ESBL), one ESBL and a carbapenemase, and one only a cephalosporinase (double-disk synergy test). Multiplex PCR and sequencing analyses showed that 37 ESBL-producing isolates harbored genes encoding CTX-M enzymes (CTX-M-15 in 33 isolates, 89.19%; and CTX-M-14 group in four isolates, 10.81%). One CTX-M-15-producing isolate co-expressed also an OXA-48-like carbapenemase. Phylogenetic group analysis of the 37 ESBL-producing and 178 non-ESBL-producing isolates indicated that the most common phylogenetic group was B2 (54.05% of ESBL-producing and 48.31% of non-ESBL-producing isolates), followed by A and D for ESBL-, and by B1, A, and F for non-ESBL-producing isolates. This is the first report highlighting the presence of MDR-EC isolates that produce both CTX-M and OXA-48-like enzymes in Sétif, Algeria.

Transmission of IMI-2 carbapenemase-producing Enterobacteriaceae from river water to human.

OBJECTIVES: Carbapenemase-producing Enterobacteriaceae (CPE) are increasing worldwide in human infections. The role of rivers as reservoirs is highlighted, but transmission from the environment to humans is not documented. A human case of bacteraemia caused by IMI-2 carbapenemase-producing Enterobacter asburiae following massive river water exposure underwent microbiological investigations with the aim of deciphering the origin and mechanism of infection. METHODS: Clinical and environmental bacterial strains were compared by resistotyping and genomotyping using pulsed-field gel electrophoresis (PFGE). PFGE was also used to determine the location of the blaIMI-2 carbapenemase gene. The patient's microbiota and river bacterial communities were compared by fingerprinting using 16S rRNA gene PCR-temporal temperature gel electrophoresis. RESULTS: Enterobacter asburiae causing bacteraemia carried the same plasmidic blaIMI-2 gene as E. asburiae strains detected in river water 1 month later. Clinical and river strains displayed identical PFGE profiles. Community fingerprinting showed the persistence in the patient's microbiota of carbapenem-resistant bacteria, which were also autochthonous in the river community (E. asburiae, Aeromonas veronii and Pseudomonas fluorescens). CONCLUSION: Here we have identified for the first time the presence of an IMI-2-producing E. asburiae in a river in the South of France and suggest transmission from the river to a human probably following intestinal translocation. General insights into transmission of CPE from the environment to humans are gained from this case. Considering the rapid spread of CPE in humans, the risk of transfer from an environmental reservoir to human microbiota should be thoroughly investigated at least by implementing environmental surveillance of carbapenem resistance.

Performance of mass spectrometric identification of clinical Prevotella species using the VITEK MS system: A prospective multi-center study.

Prevotella species, members of the human microbiota, can cause opportunistic infections. Rapid and accurate identification of Prevotella isolates plays a critical role in successful treatment, especially since the antibiotic susceptibility profile differs between species. Studies, mostly carried out using the Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) Biotyper system, showed that MALDI-TOF MS is an accurate, rapid and satisfactory method for the identification of clinically important anaerobes. In this multi-center study, we assessed the performance of the MALDI-TOF MS VITEK MS system for the identification of clinical Prevotella isolates. A total of 508 Prevotella isolates, representing 19 different species, collected from 11 European countries, Kuwait and Turkey between January 2014 and April 2016, were identified using VITEK MS (v3.0). The reliability of the identification was assessed by 16S rRNA gene sequencing. Using VITEK MS, 422 (83.1%) of the 508 isolates were identified on the species level, 459 (90.4%) on the genus level. A total of 49 (9.6%) isolates were not identified correctly. 16S rRNA gene sequencing results showed that this was partly due to the fact that several species were not represented in the database. However, some species that were represented in the database were also not identified. Five Prevotella strains were misidentified at the genus level, 2 of these strains belonged to a species not represented in the database. In general, the VITEK MS offers a reliable and rapid identification of Prevotella species, however the databases needs to be expanded.

A multicenter survey of antimicrobial susceptibility of Prevotella species as determined by Etest methodology.

Knowledge about the antimicrobial susceptibility patterns of different Prevotella species is limited. The aim of this study was to determine the current antimicrobial susceptibility of clinical isolates of Prevotella species from different parts of Europe, Kuwait and Turkey. Activity of 12 antimicrobials against 508 Prevotella isolates, representing 19 species, were tested according to Etest methodology. EUCAST, CLSI and FDA guidelines were used for susceptibility interpretations. All Prevotella species were susceptible to piperacillin/tazobactam, imipenem, meropenem, tigecycline and metronidazole. Ampicillin/sulbactam and cefoxitin also showed good activity. Ampicillin, clindamycin, tetracycline and moxifloxacin were less active; 51.2%, 33.7%, 36.8% and 18.3% of isolates were non-susceptible, respectively. A total of 49 (9.6%) isolates were resistant to three or more antimicrobials. Prevotella bivia was the most prevalent species (n = 118) and accounted for most of the multidrug-resistant isolates. In conclusion, the level of non-susceptibility to antimicrobials, which may be used for treatment of infections involving Prevotella species, are a cause of concern. This data emphasizes the need for species level identification of clinical Prevotella isolates and periodic monitoring of their susceptibility to guide empirical treatment.