A review of antimicrobial resistance in imported foods.

Antimicrobial resistance is one of the most serious threats to medical science. Food supply is recognized as a potential source of resistant bacteria, leading to the development of surveillance programs targeting primarily poultry, pork, and beef. These programs are limited in scope, not only in the commodities tested, but also in the organisms targeted (Escherichia coli, Salmonella, and Campylobacter); consequently, neither the breadth of food products available nor the organisms that may harbour clinically relevant and (or) mobile resistance genes are identified. Furthermore, there is an inadequate understanding of how international trade in food products contributes to the global dissemination of resistance. This is despite the recognized role of international travel in disseminating antimicrobial-resistant organisms, notably New Delhi metallo-beta-lactamase. An increasing number of studies describing antimicrobial-resistant organisms in a variety of imported foods are summarized in this review.

Cephalosporin-resistant Escherichia coli isolated from farm workers and pigs in northern Vietnam.

OBJECTIVE: Antimicrobial-resistant bacteria may be transmitted between farm workers and livestock. This study aimed to determine and compare the prevalence and the genetic determinants of cefotaxime-resistant and ESBL-producing Escherichia coli in faecal isolates from workers and pigs at 100 farms in northern Vietnam. METHODS: Farmers were interviewed about antimicrobial usage in livestock. Escherichia coli isolated on MacConkey agar containing 2 mg/l of cefotaxime (CTX) were tested for susceptibility to different cephalosporins by disc diffusion and screened for occurrence of ESBL-encoding genes by PCR. RESULTS: Antimicrobial usage was widespread and included classes regarded of critical or high importance in human medicine. Dosages were 0.5-2 times higher than recommended, and antimicrobials were often administered right until slaughter. Prevalence of CTX-resistant E. coli was 86% in farm workers and 89% in pigs. In 76% of farms, CTX-resistant E. coli were shared by pigs and farm workers. ESBL-producing E. coli were detected from pigs and workers at 66 and 69 farms, respectively. The ESBL phenotype was mainly mediated by CTX-M and to a lesser extent by TEM. Occurrence of blaCTX-M was similar in E. coli from pigs (66.7%) and humans (68.5%). CONCLUSION: The high occurrence of ESBL-producing E. coli in pig farmers and pigs could present a risk for spillover of these bacteria from pig farms into the community. Genomic studies are needed to elucidate reservoirs and transmission routes of ESBL-producing E. coli at livestock farms.

A survey of the antimicrobial susceptibility of Escherichia coli isolated from Sable Island horses.

The feral horses of Sable Island are a geographically isolated population located ∼160 km off the east coast of Nova Scotia, Canada. Because these horses have no contact with domestic animals, have minimal contact with people, and have never received antimicrobials, they offer a unique opportunity to study the dissemination of antimicrobial resistance in unmanaged populations. As part of an ongoing multidisciplinary and individual-based monitoring program, we collected feces from 508 geolocalized horses (92% of the total population) between July and September 2014. We selectively cultured Escherichia coli on MacConkey and CHROMagar ESBL media. Antimicrobial susceptibilities were determined, and organisms resistant to ß-lactam antimicrobials were screened for ß-lactamase genes by PCR. Escherichia coli was recovered from 146 (28.7%) individuals, and the majority of isolates (97%) were susceptible to all drugs tested. Resistance to tetracycline was most common, including organisms isolated from 4 (2.7%) of the colonized horses. A single isolate resistant to ampicillin, ceftriaxone, and ceftiofur was identified, which possessed the CTX-M-1 gene. Our findings demonstrate that although antimicrobial resistance is not common in this remote population, clinically relevant resistance genes are present.

[Temocillin and urinary tract infections]. / Place de la témocilline dans le traitement des infections urinaires.

INTRODUCTION: Temocillin is an alternative to treat urinary tract infections with bacteria producing extended spectrum beta-lactamase (ESBL). The objective is to evaluate the use of temocillin in urinary tract infections. MATERIALS AND METHODS: A systematic review of literature was carried out according to PRISMA criteria. All national and international recommendations have been reviewed regarding the indication of the use of temocillin in urology. Data collection on the use of temocillin in urinary tract infection has been performed from the Cochrane, LILACS and the Medline database. The following keywords were used: temocillin, extended spectrum beta-lactamase, urinary tract infections, urine, prostate, epididymis, testis, diffusion, pharmacokinetics, pharmacodynamics. The selection was based on the methodology, language of publication (English/French), relevance to the topic and date of publication of the articles collected. The endpoint was to provide exhaustive scientific information allowing urologists to use this antibiotic in febrile urinary infections. RESULTS: Bacteria producing ESBL has a relatively high susceptible to temocillin, ranging from 61 % to 90 %. These rates would allow its use in probabilistic. The dosage recommended is currently, in the normo-renal patient, 4g per day by intermittent infusion or continuously after a loading dose of 2g. Some studies argue, particularly in case of difficult clinical situations or obese patients, for administration of high doses (6g/24h) rather continuous infusion. There is no evident relationship between high doses and side effects. With an excellent urinary and prostatic diffusion, temocilllin might be recommend for the treatment of ESBL prostatitis. CONCLUSION: Temocillin is known to have good urinary and prostatic diffusion. According to our results, this antibiotics is now a reliable alternative for the treatment of documented ESBL urinary tract infections. LEVEL OF EVIDENCE: 4.

[Sensitivity to antibiotics uropathogens bacteria in Nouakchott - Mauritania]. / La sensibilité aux antibiotiques des bactéries uropathogènes dans la ville de Nouakchott - Mauritanie.

INTRODUCTION: A urinary tract infection (UTI) is a frequent pathology in outpatients and admitted patients as well. In recent years, there has been an increase in the resistance of germs responsible for UTI to tested antibiotics, particularly because of the emergence of Enterobacteria secreting extended-spectrum beta-lactamase (ESBL). OBJECTIVE: The aim of this work was to study the epidemiology of germs responsible for urinary tract infections and their antibiotic sensitivity at three clinical laboratories in the city of Nouakchott (Mauritania) in all patients presenting to these laboratories for urine culture during a period of six months. METHODS: This is a prospective study conducted at three clinical laboratories in Nouakchott, over a period of six months from January 1st to June 30th 2014 for all patients coming to these laboratories for urinalysis test during this period. The culture was performed according to the usual techniques, and the antibiogram was done according to the recommendations of the Antibiogram Committee of the French Society of Microbiology. The statistical analysis was performed using SPSS Statistics 20. RESULTS: From 3082 urine exam, 568 were positive, which means 18.4%. These infections were for hospitalized patients (17.8%) and outpatients in particular (82.2%). Sex ratio F/M was 1.6. The epidemiology of urinary tract infections in these three medical analysis laboratories is comparable to the past studies data regarding age, sex, and the bacteria, the most frequently responsible (Escherichia coli 64.4%). But differences in the resistance of E. coli are observed: higher resistance to beta-lactam antibiotics, the quinolones, the fluoroquinolones, and cotrimoxazol. UTI was common in patients with urinary catheter (64.9%), diabetics (52.4%), hospitalized patients (49.3%) and pregnant women (38.7%). The prevalence of urinary tract infections caused by Enterobacteria ESBL in our study was 12.8%, of all urinary tract infections caused by Enterobacteria; 10.4 and 20.4% of the E. coli and Klebsiella spp, respectively produced a ESBL. CONCLUSION: The distribution of germs in our study is comparable to the literature, however, antibiotic resistance is higher in our study, which is probably a result of the inappropriate use of these drugs in our country, therefore it is important for us to create a good strategy to supply and distribute these drugs, as well as the review of the empirical treatment of UTI in our country. LEVEL OF EVIDENCE: 4.

The role of point-of-care tests in antibiotic stewardship for urinary tract infections in a resource-limited setting on the Thailand-Myanmar border.

OBJECTIVE: Published literature from resource-limited settings is infrequent, although urinary tract infections (UTI) are a common cause of outpatient presentation and antibiotic use. Point-of-care test (POCT) interpretation relates to antibiotic use and antibiotic resistance. We aimed to assess the diagnostic accuracy of POCT and their role in UTI antibiotic stewardship. METHODS: One-year retrospective analysis in three clinics on the Thailand-Myanmar border of non-pregnant adults presenting with urinary symptoms. POCT (urine dipstick and microscopy) were compared to culture with significant growth classified as pure growth of a single organism >10(5)  CFU/ml. RESULTS: In 247 patients, 82.6% female, the most common symptoms were dysuria (81.2%), suprapubic pain (67.8%) and urinary frequency (53.7%). After excluding contaminated samples, UTI was diagnosed in 52.4% (97/185); 71.1% (69/97) had a significant growth on culture, and >80% of these were Escherichia coli (20.9% produced extended-spectrum ß-lactamase (ESBL)). Positive urine dipstick (leucocyte esterase ≥1 and/or nitrate positive) compared against positive microscopy (white blood cell >10/HPF, bacteria ≥1/HPF, epithelial cells <5/HPF) had a higher sensitivity (99% vs. 57%) but a lower specificity (47% vs. 89%), respectively. Combined POCT resulted in the best sensitivity (98%) and specificity (81%). Nearly one in ten patients received an antimicrobial to which the organism was not fully sensitive. CONCLUSION: One rapid, cost-effective POCT was too inaccurate to be used alone by healthcare workers, impeding antibiotic stewardship in a high ESBL setting. Appropriate prescribing is improved with concurrent use and concordant results of urine dipstick and microscopy.

Characterization of third-generation cephalosporin-resistant Escherichia coli from slaughter calves and fattening pigs: A pilot study for monitoring antimicrobial resistance by whole genome sequencing in Switzerland.

INTRODUCTION: Whole genome sequencing (WGS) was introduced into Swiss antimicrobial resistance monitoring in 2022 as an additional method to phenotypic antimicrobial susceptibility testing by broth microdilution to characterize presumptive third-generation cephalosporin-resistant (3GC-R) Escherichia coli. Caecal samples from Swiss slaughter calves and fattening pigs, as well as beef and pork meat from Swiss retail taken in 2021, were analyzed for the presence of 3GC-R E. coli according to European harmonized protocols. In 2021, 3GC-R E. coli was detected in 23,8 % of slaughter calves, 5,9 % of fattening pigs, and 0 % of meat. Comparative analysis of the antimicrobial resistance results obtained by phenotypic measurement and those obtained by the detection of corresponding underlying molecular mechanisms by WGS showed very high agreement (99 %). Resistance to third-generation cephalosporins (3GCs) was mainly associated with the presence of blaCTX-M-15 in E. coli isolates from calves and blaCTX-M-1 in E. coli isolates from pigs and mutations in the ampC-promoter (g.-42 C>T) in E. coli isolates from both animal species. Moreover, WGS data were used for phylogenetic analysis based on multi locus sequence types (MLST) and core genome MLST(cgMLST) revealing that 3GC-R E. coli isolated from Swiss slaughter calves and fattening pigs were genetically diverse. In this study, it was shown that using WGS alone to monitor antimicrobial resistance could detect trends in known molecular antimicrobial resistance mechanisms while also providing other valuable information about the isolates, such as genetic relatedness. However, only by combining phenotypic susceptibility testing and WGS early detection of previously unknown resistance mechanisms will be possible.

INTRODUCTION: Le séquençage du génome entier (Whole Genome Sequencing, WGS) a été introduit dans la surveillance suisse de la résistance aux antibiotiques en 2022 en tant que méthode supplémentaire aux tests phénotypiques de sensibilité aux antibiotiques pour caractériser les Escherichia coli résistants aux céphalosporines de troisième génération (3GC-R). Des échantillons de cæcum pris en 2021 à l'abattoir de veaux et de porcs suisses, ainsi que de viande de bœuf et de porc provenant de détaillants suisses ont été analysés pour détecter la présence d'E. coli 3GC-R conformément aux protocoles européens harmonisés. En 2021, les E. coli 3GC-R ont été détectés dans 23,8 % des veaux d'abattage, 5,9 % des porcs d'engraissement et 0 % dans la viande. Les résultats de résistance aux antibiotiques obtenus par mesure phénotypique et ceux obtenus par la détection des mécanismes moléculaires sous-jacents concordaient à 99 %. La résistance aux céphalosporines de troisième génération était principalement associée à la pré-sence de blaCTX-M-15 dans les isolats d'E. coli provenant de veaux et de blaCTX-M-1 dans les isolats d'E. coli provenant de porcs et à des mutations dans le promoteur ampC (g.-42 C>T) dans les isolats d'E. coli provenant des deux espèces animales. Les données WGS ont également été utilisées pour une analyse phylogénétique basée sur les types de séquences multilocus (MLST) et MLST du génome de base (cgMLST) révélant que les E. coli 3GC-R isolés des veaux et des porcs suisses étaient génétiquement divers. Dans cette étude, il a été démontré que l'utilisation du WGS seul pour surveiller la résistance aux antibiotiques pouvait détecter des tendances dans les mécanismes moléculaires connus de la résistance aux antibiotiques tout en fournissant d'autres informations précieuses sur les isolats, comme la parenté génétique. Cependant, ce n'est qu'en combinant les tests de sensibilité phénotypique avec le WGS que la détection pré-coce de mécanismes de résistance inconnus sera possible.

Characteristics of Enterobacter cloacae prosthetic joint infections.

OBJECTIVES: Enterobacter cloacae prosthetic joint infections (PJI) are rare and poorly documented. PATIENTS AND METHODS: We conducted a retrospective and monocentric study in an orthopedic unit supporting complex bone and joint infections. Between 2012 and 2016 we collected background, clinical, biological, and microbiological data from 20 patients presenting with prosthetic joint infection and positive for E. cloacae, as well as data on their surgical and medical treatment and outcome. RESULTS: Infections were localized in the hip (n=14), knee (n=5), or ankle (n=1). The median time between arthroplasty and septic revision was three years. Fourteen patients (70%) had undergone at least two surgeries due to previous prosthetic joint infections. The median time between the last surgery and the revision for E. cloacae infection was 31 days. Eleven patients (55%) were infected with ESBL-producing strains. The most frequently used antibiotics were carbapenems (n=9), cefepime (n=7), quinolones (n=7), and fosfomycin (n=4). The infection was cured in 15 patients (78.9%) after a 24-month follow-up. Five patients had a recurrent infection with another microorganism and four patients had a relapse of E. cloacae infection. The global success rate was 52.7% (58.3% for DAIR and 75% for DAIR+ciprofloxacin). CONCLUSION: Prosthetic joint infections due to E. cloacae usually occur early after the last prosthetic surgery, typically in patients with complex surgical and medical histories. The success rate seems to be increased when DAIR is associated with ciprofloxacin.

Decreased antibiotic susceptibility of Enterobacteriaceae causing community-acquired urinary tract infections in French Amazonia.

OBJECTIVES: Urinary tract infections (UTIs) have rarely been studied in the Amazon region. We aimed to describe the epidemiology of bacteria causing UTIs in French Guiana. PATIENTS AND METHODS: We performed a monocenter retrospective study of adults consulting at the emergency department of Cayenne Hospital in 2014 with a diagnosis of UTI. The bacterial species and resistance profile were described. RESULTS: Two-hundred-and-eighty-nine patients presenting with UTI were included: 82 (28.4%) presented with cystitis, 166 (57.4%) with pyelonephritis, and 41 (14.2%) with male UTI. E. coli was predominant (74.1%), and had decreased susceptibility to ampicillin, amoxicillin-clavulanic acid, fluoroquinolones, co-trimoxazole, and furans compared with data from metropolitan France. Extended-spectrum beta-lactamases (ESBL) was isolated in 3.1% of E. coli and 31.6% of K. pneumoniae. CONCLUSIONS: Antibiotic susceptibility in UTI is lower than reported in metropolitan France without evidence for an excessive consumption of antibiotics.

Extended-spectrum ß-lactamase-producing Enterobacteriaceae, national study of antimicrobial treatment for pediatric urinary tract infection.

OBJECTIVE: To evaluate clinical practices for ESBL-producing urinary tract infection (UTI) in France. METHODS: We performed an observational, retrospective, cross-sectional, hospital-based study in 22 pediatric departments of university or secondary care hospitals. We collected data of the last five patients presenting with ESBL-producing UTI in 2012 and the physicians' therapeutic approach to two case vignettes of acute non-septic ESBL-producing pyelonephritis (7-month-old girl) and cystitis (30-month-old girl). The adequacy of the therapeutic decision was analyzed by a panel of independent infectious disease experts. RESULTS: A total of 80 case patients of ESBL-producing UTI were collected: 54 with acute pyelonephritis (mean age: 28 months, female: 66%), of whom 98% received an intravenous ESBL-adapted antibiotic treatment and 55% a two-drug antibiotic therapy. Carbapenems were used in 56% of cases and aminoglycosides in 36%. Of the 26 cystitis patients (mean age: 5 years, female: 73%), 85% were treated with antibiotics, including three intravenously (carbapenems=2). For the case vignettes, physicians (n=85) would have treated the pyelonephritis patient with carbapenems (76%) and/or aminoglycosides (68%); 71% would have used a two-drug antibiotic treatment. The cystitis patient would have been treated intravenously by 29% of physicians; 8% would have used a two-drug antibiotic treatment, 16% would have prescribed carbapenems, and 11% aminoglycosides. Antibiotic treatments were deemed appropriate in 37% of cases. CONCLUSIONS: Antimicrobial treatment for ESBL-producing UTI greatly varies, and carbapenems are excessively prescribed. Specific guidelines for ESBL infections are required.

Travel and acquisition of multidrug-resistant Enterobacteriaceae.

Bacterial resistance to antibiotics is considered a major threat to health. Enterobacteriaceae have increasingly become resistant to antibiotics through the acquisition and dissemination of extended-spectrum beta-lactamases (ESBL) that confer resistance to most beta-lactams. While ESBL-producing Enterobacteriaceae were formerly restricted to hospitals, they have now spread to community settings, especially in developing countries. The tremendous expansion of international travels contributed to the importation of multidrug-resistant Enterobacteriaceae (MRE) to low prevalence countries. Several studies reported that 21 to 51% of healthy travelers acquire a MRE when travelling abroad, depending on the visited region (Asia, and especially South Asia being associated with the highest risk - up to 85%). Traveling to Africa or the Middle East is associated with lower but still disturbing rates (13-44%). In addition, the occurrence of digestive disorders and/or diarrhea and antibiotic intake increase the risk of MRE acquisition by 2-3 folds. After traveling though, the length of MRE carriage seems to be short (<1 month) and the risk of transmission within the household appears to be low. Nonetheless and beyond the intestinal carriage of MRE, traveling to endemic areas has also been pointed as a risk factor for infections involving MRE, mainly urinary tract infections.

Bacterial epidemiology and antimicrobial resistance profiles of urinary specimens of the elderly.

OBJECTIVE: Although urinary tract infections are the second leading cause of infections among patients aged above 65 years, data on bacterial epidemiology of urinary specimens in these patients is scarce. Our aim was to describe the main bacterial species found at significant levels in urine specimens of the elderly and to determine their antimicrobial resistance profiles. METHODS: From October 2012 to October 2015, all urinary specimens (catheter-related or not) received at the laboratory of microbiology of the university hospital of Caen (France) were retrospectively studied. Results were compared to those of urinary specimens of patients aged 18-64 years. Bacterial identification was performed using MALDI-TOF mass spectrometry and antimicrobial susceptibility testing was performed as per CA-SFM guidelines. RESULTS: Out of 33,302 urine cytobacteriological examinations (UCBE) performed in patients aged above 65 years, 13,450 microorganisms were identified. Escherichia coli was the most frequent species (41.8%) followed by Enterococcus faecalis (9.7%), Pseudomonas aeruginosa (5.7%), Proteus mirabilis (4.6%), and Klebsiella pneumoniae (4.2%). Around 9% of E. coli isolates were resistant to third-generation cephalosporins, including 8.2% by production of extended-spectrum ß-lactamase (ESBL). This prevalence was significantly higher than that observed in urinary specimens of patients aged 18-74 years (4.9%, P<0.001). CONCLUSION: The bacterial epidemiology of urines collected from the elderly is diverse and significantly different from that of urine specimens of younger patients, with a higher proportion of multidrug-resistant bacteria (particularly ESBL-producing E. coli).

Molecular characterization of extended spectrum beta-lactamases produced by Klebsiella pneumoniae clinical strains from a Tunisian Hospital.

OBJECTIVES: Extended-spectrum ß-lactamases are widespread in hospital settings worldwide. The prevalence of ESBL producing Klebsiella pneumoniae (ESBL-KP) strains isolated from patients has recently increased in Tunisia. We conducted this study to determine the prevalence and the genetic characterization of ESBL-KP in a Tunisian Hospital. PATIENTS AND METHODS: We performed antibiotic susceptibility testing, multiplex PCR, and DNA sequencing analysis on 118 non repetitive K. pneumonia strains isolated during three years, to determine the prevalence and genotypes of ESBL among K. pneumoniae clinical isolates. RESULTS: Most ESBL-producing K. pneumonia strains were isolated from hospitalized patients, especially in neonatal and pediatric wards. The resistance to other antibiotics was high. Most of the pathogens were isolated from the urinary tract (86.44%). Carbapenems were the most effective antimicrobial agents followed by amikacin and fosfomycin. The rate of blaSHV, blaTEM, and blaCTX-M genes among the isolates was 89, 56.78, and 81.35%, respectively. Sequencing revealed the amplicons encoding TEM-1, TEM-53, TEM-158, SHV-1, SHV-11, SHV-28, CTX-M-15, CTX-M-15-like. The blaCTX-M-15 was the dominant gene among Tunisian isolates, but this was the first report of blaTEM-53 and blaTEM-158 genes in the country. CONCLUSIONS: Our results confirm the predominance of CTX-M-15 in Tunisia. To our knowledge, this is the first report of TEM-158 and TEM-53 in Tunisia.

Non-carbapenem therapy of urinary tract infections caused by extended-spectrum ß-lactamase-producing Enterobacteriaceae.

PURPOSE: We determined the prevalence of ESBL Enterobacteriaceae in urinary tract infections among inpatients, identified risk factors of acquisition, and evaluated the effectiveness of alternatives to carbapenems. METHODS: The clinical, microbiological, and therapeutic data as well as the outcomes were recorded for all ESBL-E positive urine samples for three months. RESULTS: Thirty-one (4%) of the 762 Enterobacteriaceae positive cultures were ESBL producers. The predisposing conditions for being infected with those strains were: immunodepression (61%), recent hospitalization (52%), recent antibiotic therapy (52%), and urinary catheterization (61%). 19% of infections were community acquired. The seven cases of acute pyelonephritis and five of prostatitis were treated with piperacillin-tazobactam (5), fluoroquinolones (4), ceftazidime (2), or carbapenems (only 1) after specialized advice. Four (33%) patients relapsed at week 10: three were immunodepressed and three presented with bacteremia. CONCLUSIONS: Alternatives to carbapenems (especially piperacillin-tazobactam) seem to be a good option for non-bacteremic UTI in immunocompetent patients.

Detection of Ambler class A, B and D ß-lactamases among Pseudomonas aeruginosa and Acinetobacter baumannii clinical isolates from burn patients.

In this study, we evaluated the existence of classes A, B and D ß-lactamases among Pseudomonas aeruginosa (P.aeruginosa) and Acinetobacter baumannii (A.baumannii) strains isolated from burn patients in Tehran during the years 2012 and 2013. From these strains, the frequency of MBL (metallo-beta-lactamase) and ESBL (extended-spectrum beta-lactamase) producers were evaluated using CDDT (Combined Disk Diffusion Tests). The prevalence of some related genes, including blaIMP, blaVIM, blaSPM, blaKPC, blaGIM, blaDIM, blaBIC, blaOXA-48, blaCTX-M-15 and blaNDM genes, was evaluated using PCR and sequencing methods. Of the 75 non-fermenter isolates, 47 P.aeruginosa and 28 A.baumannii were isolated and identified. A high rate of resistance to common antibiotics was detected among A.baumannii isolates in particular, showing 100% resistance to 9 tested antibiotics. CDDT showed that 21 (28%) and 25 (34.25%) of the non-fermenter isolates were ESBL and MBL producers respectively. The prevalence of blaCTX-M-15 and blaIMP genes among the 75 non-fermenter isolates was 7 (9.3%) and 1 (1.3%), respectively. Fortunately, no other genes were detected in either of the non-fermenters. The mortality rate due to MBL-producing isolates was 5 (20%). This study showed specific resistance genes exist among some MBL and ESBL gram-negative non-fermenters which were isolated from burn patients in Tehran.

Dans cette étude, nous avons évalué l'existence des classes A, B et D de ß-lactamases chez les souches de Pseudomonas aeruginosa (P.aeruginosa) et Acinetobacter baumannii (A.baumannii) isolées des patients brûlés à Téhéran pendant les années 2012 et 2013. La fréquence des producteurs du MBL (métallo-bêta-lactamase) et du BLSE (bêta-lactamase à spectre étendu) a été évaluée par les tests de diffusion sur les disques combinées, et la prévalence de certains gènes liés (y compris les gènes blaIMP, blaVIM, blaSPM, blaKPC, blaGIM, blaDIM, blaBIC, blaOXA-48, blaCTX-M-15 et blaNDM) a été vérifiée avec des tests pour réaction en chaine à la polymérase et les méthodes de séquençage. Un totale de 75 isolats non-fermenteurs ont été isolés et identifiés : 47 étaient P.aeruginosa et 28 étaient A.baumannii. Un taux élevé de résistance aux antibiotiques communs a été détecté parmi les isolats d'A.baumannii en particulier, avec une résistance de 100% aux 9 antibiotiques testés. Les tests de diffusion des disques combinés a montré que 21 (28%) et 25 (34,25 %) des isolats non-fermenteur étaient producteurs du BLSE et du MBL respectivement. La prévalence des gènes blaCTX-M-15 et blaIMP parmi les 75 isolats non-fermenteurs était 7 (9,3%) et 1 (1,3%), respectivement. Heureusement, d'autres gènes n'ont pas été détectés. Le taux de mortalité due aux isolats producteurs des MBL était 5 (20%). Cette étude a montré que des gènes avec des résistances spécifiques existent parmi certains non-fermenteurs MBL et BLSE Gram-négatifs qui ont été isolés des patients brûlés à Téhéran.

Epidemiology of third-generation cephalosporin-resistant community-acquired Enterobacteria isolated from elderly patients.

AIMS: This survey was made to study the epidemiology of multiresistant bacteria (MRB) in the French community, among elderly patients 65 years of age or more, carrying third-generation cephalosporin-resistant (3GC-resistant) Enterobacteriaceae, and the co-resistance of prescribed antibiotics. METHODS: The data was collected in 2009 in the West of France by MedQual, a network of 174 private laboratories. RESULTS: Two thousand one hundred and sixty strains of the 88,255 identified Enterobacteria strains were 3GC-resistant (2.4%) and 945 of these strains (41.8%) were isolated from elderly patients 65 years of age or more. Escherichia coli was the predominant 3GC-resistant strain (72.7%). 51.4% of the 945 patients in whom a 3GC-resistant strain was isolated produced an extended-spectrum ß-lactamase (ESBL). The main risk factors for infection with the 3GC-resistant strain were hospitalization and antibiotic treatment in the previous year (58.2 and 86.9%, respectively). Hospitalization during the previous year was more frequent among elderly patients who lived at home compared with those who lived in nursing homes (P<0.05). The production of ESBL, among the 945 patients who carried the 3GC-resistant strains, was similar among patients who lived at home compared with those who lived in nursing homes (51.4% versus 49.7%). CONCLUSION: Microbiologists should warn family physicians about MRB isolates with a specific antimicrobial resistance pattern (3GC-resistant, fluoroquinolone-resistant, etc.) to prescribe more effective medications.

Clinical spectrum of urine cultures positive for ESBL-producing Escherichia coli in hospitalized patients and impact on antibiotic use.

OBJECTIVE: We wanted to describe the clinical features associated with urinalysis positive for ESBL-producing Escherichia coli and their impact on antibiotic use. METHODS: We performed a prospective observational study in 13 French hospitals of the Paris area for 3 consecutive months. We included all patients with urine cultures positive for ESBL-producing E. coli. RESULTS: One hundred and seventeen of the 218 patients (54%) presented with asymptomatic bacteriuria, 31 (14%) with cystitis, and 70 (32%) with a parenchymal infection. Nineteen patients with asymptomatic bacteriuria (16%) received antibiotics. Forty-one with parenchymal infections (59%) received a carbapenem. A carbapenem alternative could have been used in every patient treated with a carbapenem, according to antibiotic susceptibility testing results. CONCLUSIONS: Urinary tract infections accounted for 46% of E. coli ESBL positive urinalysis. Fifty percent of parenchymal infections were treated with a carbapenem.