Cephalosporin-resistant Strains Research Articles

Antimicrobial Resistance in Sexually Transmitted Infections: Current Trends

The review article discusses current trends in antibiotic resistance in bacterial and protozoal sexually transmitted infections (STIs). Antimicrobial resistance in STIs has increased significantly in recent decades due to the overuse and misuse of antibiotics, fueled by population migration and the high incidence of STIs worldwide. While emerging cephalosporin-resistant strains of Neisseria gonorrhoeae are one of the most pressing problems in the world, other pathogenic STIs that are resistant to antibiotics, such as Mycoplasma genitalium and Chlamydia trachomatis, are increasingly being reported. The emergence of multidrugresistant strains of bacterial STIs is of particular concern for researchers. The emerging global crisis in STI treatment is the result of neglect and inattention to repeated warnings from researchers about the emergence of STI strains resistant to the existing antibiotics, as well as shifting priorities in the pharmaceutical industry, which limited the development of new antibiotics. The current antimicrobial portfolio does not provide cause for optimism, as it contains few new antibiotics, and most developments are in the early stages of clinical trials. Experts have suggested that the failure of existing STI treatment regimens is largely inevitable and have called for the creation of entirely new classes of antimicrobial drugs that would take decades to develop. Currently, there are several promising alternative strategies for the treatment of antibiotic-resistant STIs. The use of phage therapy, antimicrobial peptides, and hydrolytic enzymes are particularly promising directions.

Affinity of β-Lactam Antibiotics for Neisseria gonorrhoeae Penicillin-Binding Protein 2 Having Wild, Cefixime-Reduced-Susceptible, and Cephalosporin (Ceftriaxone)-Resistant penA Alleles.

Multidrug-resistant Neisseria gonorrhoeae is a serious concern worldwide. Resistance to β-lactam antibiotics occurs through mutations in penicillin-binding proteins (PBPs), acquisition of β-lactamases, and alteration of antibiotic penetration. Mosaic structures of penA, which encodes PBP2, play a major role in resistance to β-lactams, especially cephalosporins. Ceftriaxone (CRO) is recognized as the only satisfiable antibiotic for the treatment of gonococcal infections; however, CRO-resistant isolates have emerged in the community. Here, we examined the affinity of β-lactam antibiotics for recombinant PBP2 in a competition assay using fluorescence-labeled penicillin. We found no or little difference in the affinities of penicillins and meropenem (MEM) for PBP2 from cefixime (CFM)-reduced-susceptible strain and cephalosporin-resistant strain. However, the affinity of cephalosporins, including CRO, for PBP2 from the cephalosporin-resistant strain was markedly lower than that for PBP2 from the CFM-reduced-susceptible-resistant strain. Notably, piperacillin (PIP) showed almost the same affinity for PBP2 from penicillin-susceptible, CFM-reduced-susceptible, and cephalosporin (including CRO)-resistant strains. Thus, PIP/tazobactam and MEM are candidate antibiotics for the treatment of CRO-resistant/multidrug-resistant N. gonorrhoeae.

Cephalosporin resistance, tolerance, and approaches to improve their activities.

Cephalosporins comprise a β-lactam antibiotic class whose first members were discovered in 1945 from the fungus Cephalosporium acremonium. Their clinical use for Gram-negative bacterial infections is widespread due to their ability to traverse outer membranes through porins to gain access to the periplasm and disrupt peptidoglycan synthesis. More recent members of the cephalosporin class are administered as last resort treatments for complicated urinary tract infections, MRSA, and other multi-drug resistant pathogens, such as Neisseria gonorrhoeae. Unfortunately, there has been a global increase in cephalosporin-resistant strains, heteroresistance to this drug class has been a topic of increasing concern, and tolerance and persistence are recognized as potential causes of cephalosporin treatment failure. In this review, we summarize the cephalosporin antibiotic class from discovery to their mechanisms of action, and discuss the causes of cephalosporin treatment failure, which include resistance, tolerance, and phenomena when those qualities are exhibited by only small subpopulations of bacterial cultures (heteroresistance and persistence). Further, we discuss how recent efforts with cephalosporin conjugates and combination treatments aim to reinvigorate this antibiotic class.

Exploring multidrug-resistant Klebsiella pneumoniae antimicrobial resistance mechanisms through whole genome sequencing analysis

BackgroundAntibiotic-resistant Klebsiella pneumoniae has emerged as a critical public health threat worldwide. Understanding the antimicrobial resistance mechanisms of multidrug-resistant K. pneumoniae (MDR-Kp) and its prevalence in time and space would provide clinical significance for managing pathogen infection.MethodsEighteen clinical MDR-Kp strains were analyzed by whole genome sequencing (WGS), and the antimicrobial resistance genes and associated resistance mechanisms were compared with results obtained from the conventional microbiological test (CMT). The sequence homology across strains in our study and those previously collected over time from a wide geographical region was assessed by phylogenetic analysis.ResultsMDR-Kp strains were collected from eighteen patients who had received empirical treatment before strain collection, with sputum (83.3%, 15/18) being the primary source of clinical samples. The commonly received treatments include β-lactamase inhibitors (55.6%, 10/18) and carbapenems (50%, 9/18). Using CMT, we found that all 18 strains were resistant to aztreonam and ciprofloxacin, while 14 (77.8%) showed resistance to carbapenem. Polymyxin B and tigecycline were the only antibiotics to which MDR-Kp strains were sensitive. A total of 42 antimicrobial resistance mechanisms were identified by WGS, surpassing the 40 detected by the conventional method, with 25 mechanisms shared between the two techniques. Despite a 100% accuracy rate of WGS in detecting penicillin-resistant strains, the accuracy in detecting cephalosporin-resistant strains was only at 60%. Among all resistance genes identified by WGS, Klebsiella pneumoniae carbapenemase-2 (KPC-2) was present in all 14 carbapenem-resistant strains. Phenotypic analysis indicated that sequence type (ST) 11 isolates were the primary cause of these MDR-Kp infections. Additionally, phylogenic clustering analysis, encompassing both the clinical and MDR-Kp strains previously reported in China, revealed four distinct subgroups. No significant difference was observed in the sequence homology between K. pneumoniae strains in our study and those previously collected in East China over time.ConclusionThe application of WGS in identifying potential antimicrobial-resistant genes of MDR-Kp has demonstrated promising clinical significance. Comprehensive genomic information revealed by WGS holds the promise of guiding treatment decisions, enabling surveillance, and serving as a crucial asset in understanding antibiotic resistance.

High Levels of Antibiotic Resistance in MDR-Strong Biofilm-Forming Salmonella Typhimurium ST34 in Southern China.

Salmonella enterica subsp. enterica serovar Typhimurium (S. typhimurium) is an important zoonotic pathogen with important public health significance. To understand S. typhimurium's epidemiological characteristics in China, multi-locus sequence typing, biofilm-forming ability, antimicrobial susceptibility testing, and resistant genes of isolates from different regions and sources (human, food) were investigated. Among them, ST34 accounted for 82.4% (243/295), with ST19 ranking second (15.9%; 47/295). ST34 exhibited higher resistance levels than ST19 (p < 0.05). All colistin, carbapenem, and ciprofloxacin-resistant strains were ST34, as were most cephalosporin-resistant strains (88.9%; 32/36). Overall, 91.4% (222/243) ST34 isolates were shown to have multidrug resistance (MDR), while 53.2% (25/47) ST19 isolates were (p < 0.05). Notably, 97.8% (45/46) of the MDR-ACSSuT (resistance to Ampicillin, Chloramphenicol, Streptomycin, Sulfamethoxazole, and Tetracycline) isolates were ST34, among which 69.6% (32/46) of ST34 isolates were of human origin, while 30.4% (14/46) were derived from food (p < 0.05). Moreover, 88.48% (215/243) ST34 showed moderate to strong biofilm-forming ability compared with 10.9% (5/46) ST19 isolates (p < 0.01). This study revealed the emergence of high-level antibiotic resistance S. typhimurium ST34 with strong biofilm-forming ability, posing concerns for public health safety.

Collateral sensitivity profiling in drug-resistant Escherichia coli identifies natural products suppressing cephalosporin resistance

The rapid emergence of antimicrobial resistance presents serious health challenges to the management of infectious diseases, a problem that is further exacerbated by slowing rates of antimicrobial drug discovery in recent years. The phenomenon of collateral sensitivity (CS), whereby resistance to one drug is accompanied by increased sensitivity to another, provides new opportunities to address both these challenges. Here, we present a high-throughput screening platform termed Collateral Sensitivity Profiling (CSP) to map the difference in bioactivity of large chemical libraries across 29 drug-resistant strains of E. coli. CSP screening of 80 commercial antimicrobials demonstrated multiple CS interactions. Further screening of a 6195-member natural product library revealed extensive CS relationships in nature. In particular, we report the isolation of known and new analogues of borrelidin A with potent CS activities against cephalosporin-resistant strains. Co-dosing ceftazidime with borrelidin A slows broader cephalosporin resistance with no recognizable resistance to borrelidin A itself.

The cephalosporin-resistant bacterial strains from urinary tract

The cephalosporin-resistant bacterial strains from urinary tract

The cephalosporin-resistant bacterial strains from urinary tract

Urinary tract infections are considered of great relevance among infections of bacterial origin as one of the third most important bacterial infections worldwide. These infections are caused by bacteria belonging to the Enterobacteriaceae family, such as Escherichia coli, which is the most frequently isolated uropathogen. The objective was to determine the level of resistance to cefotaxime and ceftazidime in bacterial strains from urinary tract infections. Material and methods. The study strains were isolated from patients who presented urinary tract infections, the genus and species were ratified by conventional microbiological methods. The antimicrobial sensitivity test was performed using the Kirby Bauer method and minimum inhibitory concentration, testing β-lactams that belong to the family of third-generation cephalosporins (cefotaxime and ceftazidime). The presence of extended-spectrum β-lactamases was searched for by the combined disc method. Forty-three bacterial strains from a collection of strains from the Microbiology Laboratory of the Faculty of Chemical Sciences, BUAP, were analyzed. All the strains studied showed resistance to the antimicrobials tested and production of the extended-spectrum β-lactamase enzyme. This study showed that E. coli continues to be the most frequent uropathogen responsible for urinary tract infections. It also showed the participation of resistance mechanisms, such as the presence of extended-spectrum β-lactamases, which confer high resistance values ​​to third generation cephalosporins, reflecting the need to implement measures for the use of antimicrobials in our community.

Clinical and bacteriological profile of culture-negative and culture-proven neonatal sepsis in Palembang, Indonesia

Culture-negative and multidrug-resistant neonatal sepsis frequently occur in developing countries and complicate neonatal sepsis management. These conditions contribute to a high neonatal mortality rate and accelerate the misuse of antibiotics. However, the extent of culture-negative and multidrug-resistant neonatal sepsis in developing countries remains poorly characterized. This study aims to describe culture-negative and culture-proven neonatal sepsis epidemiology and the antimicrobial resistance patterns in Palembang, Indonesia. A retrospective review of the medical records of all neonatal admissions between January 2016 and December 2018 was conducted at a tertiary-level referral hospital in Indonesia. The maternal and neonatal characteristics and microbiological results of the identified sepsis cases were obtained and analyzed. Three hundred and fifty-six neonatal sepsis cases were admitted from 2016 to 2018, accounting for 14.1% of neonatal hospital admissions. The percentages of early-onset and late-onset sepsis were comparable (49.7% vs. 50.3%), with an 18.1% case fatality rate. The proportion of culture-negative sepsis was 44%. The mortality rates between culture-proven and culture-negative sepsis cases did not differ statistically (p = 0.11). Coagulase-negative staphylococci (30.9%), Klebsiella pneumoniae (18.1%), and Acinetobacter spp. (10.7%) were the most frequently isolated pathogens. Overall, 62.6% of all isolated organisms were multidrug-resistant bacteria, with a high prevalence of extended-spectrum cephalosporin-resistant and carbapenem-resistant strains. Culture-negative sepsis accounts for a significant proportion of neonatal sepsis cases. Early- and late-onset and culture-negative and culture-proven neonatal sepsis contribute to a comparable proportion of neonatal sepsis morbidity and mortality. There is an alarmingly high prevalence of resistance to extended-spectrum cephalosporin and carbapenem in neonatal sepsis cases.

Emergence of a Novel Lineage and Wide Spread of a blaCTX-M-15/IncHI2/ST1 Plasmid among Nosocomial Enterobacter in Guadeloupe.

Between April 2018 and August 2019, a total of 135 strains of Enterobacter cloacae complex (ECC) were randomly collected at the University Hospital Center of Guadeloupe to investigate the structure and diversity of the local bacterial population. These nosocomial isolates were initially identified genetically by the hsp60 typing method, which revealed the clinical relevance of E. xiangfangensis (n = 69). Overall, 57/94 of the third cephalosporin-resistant strains were characterized as extended-spectrum-β-lactamase (ESBL) producers, and their whole-genome was sequenced using Illumina technology to determine the clonal relatedness and diffusion of resistance genes. We found limited genetic diversity among sequence types (STs). ST114 (n = 13), ST1503 (n = 9), ST53 (n = 5) and ST113 (n = 4), which belong to three different Enterobacter species, were the most prevalent among the 57 ESBL producers. The blaCTXM-15 gene was the most prevalent ESBL determinant (56/57) and was in most cases associated with IncHI2/ST1 plasmid replicon carriage (36/57). To fully characterize this predominant blaCTXM-15/IncHI2/ST1 plasmid, four isolates from different lineages were also sequenced using Oxford Nanopore sequencing technology to generate long-reads. Hybrid sequence analyses confirmed the circulation of a well-conserved plasmid among ECC members. In addition, the novel ST1503 and its associated species (ECC taxon 4) were analyzed, in view of its high prevalence in nosocomial infections. These genetic observations confirmed the overall incidence of nosocomial ESBL Enterobacteriaceae infections acquired in this hospital during the study period, which was clearly higher in Guadeloupe (1.59/1000 hospitalization days) than in mainland France (0.52/1,000 hospitalization days). This project revealed issues and future challenges for the management and surveillance of nosocomial and multidrug-resistant Enterobacter in the Caribbean.

Penicillin- and third-generation cephalosporin-resistant strains of Streptococcus pneumoniae meningitis: Case report and literature review

BackgroundTreatment of patients with penicillin-resistant S. pneumoniae (PRSP) is complicated because of the relatively poor blood-brain barrier penetration of effective antimicrobials. Our case: A previously healthy 70-year-old woman, a traveler from China to Japan, was admitted to our hospital with fever and loss of consciousness. She has no history of pneumococcal vaccination. She was diagnosed with bacterial meningitis due to penicillin-and third-generation cephalosporin-resistant strains of S. pneumoniae. The patient was successfully treated with a combination therapy of vancomycin (VCM) and levofloxacin (LVFX) and recovered without any neurological sequelae. As the treatment of penicillin-and third-generation cephalosporin-resistant strains of S. pneumoniae meningitis remains unclear, we conducted a review of the reported cases of meningitis caused by penicillin- and cephalosporin-resistant S. pneumoniae. MethodWe performed a search using the keywords “penicillin-resistant Streptococcus pneumoniae,” “meningitis,” and “pneumococcal meningitis”. We searched the electronic databases PubMed, Embase, and Ichushi from their inception to March 2020. Subsequently, two authors independently reviewed the resulting database records, retrieved full texts for eligibility assessment, and extracted data from these cases. ResultWe identified 18 papers describing thirty-five cases of penicillin- and cephalosporin-resistant S. pneumoniae meningitis including our case. The patient's characteristics were; median age: 50 years, men:50%, 85% of cases received combination regimens of antibiotics: Ceftroriaxone (CTRX) plus VCM (20 cases), CTRX plus VCM plus rifampicin (RFP) (two cases), CTRX plus linezolid (one case), fluoroquinolones (two cases), carbapenems (six cases), Thirty-five percent received steroids. Twenty-four percent of patients died. Twenty-six percent of patients complicated neurological sequalae. ConclusionCombination therapy including VCM plus LVFX could be a treatment option.

The role of Musca domestica and milk in transmitting pathogenic multidrug-resistant Escherichia coli and associated phylogroups to neonatal calves.

Escherichia coli, as a global source of antimicrobial resistance, is a serious veterinary and public health concern. The transmission of pathogenic multidrug-resistant (MDR) E. coli within diarrheic calves and its correlation with Musca domestica and milk strains have been investigated. In total, 110, 80, and 26 E. coli strains were obtained from 70 rectal swabs from diarrheic calves, 60 milk samples and 20M. domestica, respectively. Molecular pathotyping of E. coli revealed the presence of pathogenic E. coli with a higher percentage of shigatoxigenic strains within diarrheic calves and M. domestica at 46.4% and 34.6%, respectively. Phenotypic antimicrobial resistance revealed higher β-lactams resistance except for cefquinome that exhibited low resistance in M.domestica and milk strains at 30.8% and 30%, respectively. The extended-spectrum cephalosporin (ESC) resistant strains were detected within fecal, M. domestica, and milk strains at 69.1%, 73.1%, and 71.3%, respectively. All E. coli strains isolated from M. domestica exhibited MDR, while fecal and milk strains were harboring MDR at 99.1% and 85%, respectively. Molecular detection of resistant genes revealed the predominance of the blaTEM gene, while none of these strains harbored the blaOXA gene. The highest percentages for blaCTXM and blaCMYII genes were detected in M. domestica strains at 53.8% and 61.5%, respectively. Regarding colistin resistance, the mcr-1 gene was detected only in fecal and milk strains at 35.5% and 15%, respectively. A high frequency of phylogroup B2 was detected within fecal and M. domestica strains, while milk strains were mainly assigned to the B1 phylogroup. Pathogenic E. coli strains with the same phenotypic and genotypic antimicrobial resistance and phylogroups were identified for both diarrheic calves and M. domestica, suggesting that the possible role of M. domestica in disseminating pathogenic strains and antimicrobial resistance in dairy farms.

Case Series of Three Patients with Disseminated Gonococcal Infection and Endocarditis.

IntroductionThe increasing incidence of Neisseria gonorrhoeae infections and emergence of cephalosporin-resistant strains means the threat of disseminated gonococcal infection and endocarditis needs to be reimagined into the differential diagnosis for patients treated in the emergency department (ED) for sexually transmitted infections and for endocarditis itself. Only 70 cases of disseminated gonococcal infection (DGI) with endocarditis had been reported through 2014.1–4 In 2019, however, an outbreak of DGI with one case of endocarditis was reported.5 This case series of three patients with DGI and endocarditis, in addition to the recent outbreak, may represent a warning sign for reemergence of this threat.Case ReportWe describe three cases within a recent three-year period of gonococcal endocarditis as seen and treated at our institution. These cases show divergent presentations of this insidious disease with both classical and atypical features. One case displayed a classic migratory rash with positive urine testing and a remote history of sexually transmitted infections, while another patient developed isolated culture-confirmed endocarditis with negative cervical testing and imaging, and the final case was a male patient who presented to the ED with fulminant endocarditis as the first ED presentation of infection.ConclusionSecondary to an overall rise in incidence and possibly due to increasing antibiotic-resistance patterns, gonococcal endocarditis should be included in the differential diagnosis of any case of endocarditis. Reciprocally, increased vigilance should surround the evaluation of any patient for sexually transmitted diseases while in the ED for both the development of DGI and endocarditis.

Characterization of antimicrobial resistance in chicken-source phylogroup F Escherichia coli: similar populations and resistance spectrums between E. coli recovered from chicken colibacillosis tissues and retail raw meats in Eastern China

The extended-spectrum cephalosporin resistant E. coli from food animals transferring to community settings of humans causes a serious threat to public health. Unlike phylogroup B2 E. coli strains, the clinical significance of isolates in phylogroup F is not well revealed. Here, we report on a collection (n = 563) of phylogroup F E. coli isolates recovered from chicken colibacillosis tissues and retail raw chicken meat samples in Eastern China. There was an overlapped distribution of MLST types between chicken colibacillosis-origin and meat-source phylogroup F E. coli, including dominant STs (ST648, ST405, ST457, ST393, ST1158, etc). This study further investigated the presence of extended-spectrum β-lactamase (ESBL/pAmpC) producers in these chicken-source phylogroup F E. coli strains. The prevalence of extended-spectrum cephalosporin resistant strains in phylogroup F E. coli from chicken colibacillosis and raw meat separately accounted for 66.1 and 71.2%. The resistance genotypes and plasmid replicon types of chicken-source phylogroup F E. coli isolates were characterized by multiplex PCR. Our results revealed β-lactamase CTX-M, OXA, CMY and TEM genes were widespread in chicken-source phylogroup F E. coli, and blaCTX-M was the most predominant ESBL gene. Moreover, there was a high prevalence of non-lactamase resistance genes in these β-lactam-resistant isolates. The replicons IncB/O/K/Z, IncI1, IncN, IncFIC, IncQ1, IncX4, IncY, and p0111, associated with antibiotic-resistant large plasmids, were widespread in chicken-source phylogroup F E. coli. There was no obvious difference for the populations, resistance spectrums, and resistance genotypes between phylogroup F E. coli from chicken colibacillosis tissues and retail meats. This detail assessment of the population and resistance genotype showed chicken-source phylogroup F E. coli might hold zoonotic risk and contribute the spread of multidrug-resistant E. coli to humans.

P682 Antibiotic resistome profiles of fecal Escherichia coli isolates in association with Crohn’s disease

Abstract Background In recent years, there was a growing interest in the modulation and manipulation of the intestinal flora to treat patients through fecal microbiota transplantation (FMT). Unfortunately, 2 cases of bacteremia via FMT in 2019 occurred in patients due to extended-spectrum beta–lactamase–producing E. coli from the same stool donor. However, one of the recipients did not get an active infection. So, the association between health status and bacterial ability to resist chemicals requires further investigations. Methods Totally, 63 E. coli strains from 32 fecal samples (14 CD patients and 18 controls) were whole-genome sequenced on the Miseq platform (project #0671-2020-0058). The strains were tested against 15 antibiotics by a disc-diffusion assay according to EUCAST guidelines. E. coli ATCC 25922 was used as a control. Antibiotic resistance genes were predicted by the Resistance Gene Identifier and CARD database. Results All strains tested were susceptible only to meropenem (Figure 1). The proportion of multidrug-resistant strains in CD patients and controls did not differ significantly. Strains from both groups differed in sensitivity to amikacin and levofloxacin (Fisher’s exact test, p&amp;lt;0.1). Ciprofloxacin, widely used in therapy, was less effective against CD-derived strains (15%) compared to controls (3%). The inefficiency of fluoroquinolones could be due to plasmid-associated genes (qnrS1, qnrB19) and mutations in chromosome genes (gyrA, parC). Several strains carried aminoglycoside transferase genes, but only 1 CD-derived strain was non-sensitive. Susceptibility to tetracyclines did not differ between groups, and almost all strains, growing on the antibiotic, contained efflux pump genes (tetA, tetB, tetD, tetR). About half of the strains from both groups were active against penicillins carrying genes for class A (TEM-1, TEM-150) and D beta-lactamases (OXA-1). TEM-150 was only in control strains. Cephalosporin-resistant strains were in both groups and harbored AmpC type β-lactamases. Almost all strains had multidrug efflux systems (MdtEF-TolC, EmrAB-TolC, EmrKY-TolC, AcrAB-TolC), MdtG and AcrD efflux pumps, and their regulators. Although all strains contained pmrF and pmrC genes, only 1 CD-derived strain was non-sensitive to polymyxin. Figure 1. Antibiotic resistance of E. coli strains (in %, * - p &amp;lt; 0.1) Conclusion Thus, the differences in susceptibility between CD- and control-derived strains were revealed. However, E. coli strains from healthy subjects contained antibiotic resistance genes and demonstrated activity against antibiotics of various categories, which might be crucial and should be taken into account for a safe and effective therapy in the treatment of CD.

Association of ESBL and CTX-M gene with the clinical outcome of patients suffer from bloodstream infections caused by Escherichia coli and Klebsiella pneumoniae

Objective: To evaluate the value of CTX-M on the clinical outcome of bloodstream infection (BSI) patients caused by E. coli and K. pneumoniae. Subject and method: A total of 165 BSI patients were treated at 108 Military Central Hospital from Oct. 2014 to May 2016, including 115 cases caused by E. coli and 50 cases caused by K. pneumoniae. All strains were identified and performed antibiotic susceptible test by Vitek II system (Bio-Merieux, USA). CTX-M gene encoding ESBL was screened using polymerase chain reaction method. Result: In total, the percentage of ESBLs producing strains was 47.3% and CTX-M was detected in 62.4% (103/165) all of strains. We observed that there was not significant difference with the clinical outcome between BSI patients caused by CTX-M positive strains (septic shock 22.3% and fatality 21.4%) and BSI patients caused by cephalosporin resistant strains (17.9% - 22.5% with shock and 17.9% - 22.5% with fatality). However, when we analyzed the subgroup of BSI patients caused by cephalosporin susceptible strains. The proportion of shock and fatality in groups with CTX-M positive were higher than that in group with CTX-M negative (21.6% - 33.3% vs 14.6% - 19.2% with shock and 18.9% - 26.7% vs 10.4 - 15.4% with fatality). Additionally, the length of hospital stay in groups with CTX-M positive were significant longer than that in group with CTX-M negative. Conclusion: Our data showed a high prevalence of ESBL producing strains causing BSI patients, and also high prevalence of CTX-M positive strains. Moreover, in BSIs caused by cephalosporin susceptible strains, the clinical outcome of group with CTX-M positive were worse than that of group with CTX-M negative.

Emergence of Third Generation Cephalosporin Resistant Escherichia coli in Infants: Retrospective Study from a Tertiary Care Hospital in South India

Aim: This study was aimed to evaluate the emergence of third generation cephalosporin resistant Escherichia coli isolated from the culture of various biological fluids of infants in a tertiary care hospital. Background: Resistance to commonly used antibiotics is consistently increasing during the last decades and it was found varying with time and geographical location. Objectives: To determine the prevalence of third generation cephalosporin sensitivity pattern of E. coli isolated from urine, stool, and throat swab culture from laboratory records. Methods: The retrospective study included the laboratory report of antibiotic sensitivity conducted on infants specimens during the period of 2 years. Third generation cephalosporin sensitivity patterns of E. coli isolated from urine, stool, and throat swab culture were collected and data were statistically analyzed. Results: Reports of 351 samples with positive E. coli were included in the study. More samples were analyzed from infants above 6 months of age with female dominance (184/351). Among the specimens tested, urine samples were highest 128/351 (35.0%). Cephalosporin resistant strain was found in 243/351 samples (69.2%) (p=0.0463) with 218/243 (89.7%) isolated from infants above 6 months of age and 25/243 (10.2%) were from infants below 6 months of age (p=0.038). The frequency of cephalosporin resistant E. coli in urine specimens of male and female infants was significant (p=0.0001). Conclusion: Third generation cephalosporin resistant E. coli strain was found in 69.2% of isolates and more in urine samples from female infants above 6 months of age. The clinicians should consider the emergence of cephalosporin resistant E. coli while selecting antibiotics as empirical treatment.

Temocillin susceptibility among Enterobacterales strains recovered from blood culture in France

Temocillin is used for several years in some European countries but, only since 2015 in France. We assessed the susceptibility of Enterobacterales strains isolated from blood culture 1 year before (2014) and 2 years after (2017) its use in France. 1,387 strains were included by 17 clinical laboratories located throughout France: 363 in 2014 and 1,024 in 2017. The rate of resistance to temocillin was 4.6% and 26.7% in 3rd generation cephalosporin (3GC) susceptible and resistant strains respectively. Cephalosporinase-overproducer (COPE) strains were significantly more resistant to temocillin (37.7%) than ESBL-producer (ESBL-PE) (23.5%) (P < 0.01). The rate of temocillin resistance was correlated to the number of inactive beta-lactams. The rate of resistance to temocillin trend to increase from 13.9% in 2014 to 23.9% in 2017 (P < 0.01). Temocillin remains highly active against Enterobacterales but the trend in resistance should be assessed over time.

Prevalence and molecular characterization of β-lactamase producers and fluoroquinolone resistant clinical isolates from North East India

IntroductionThe rapid emergence and variations of antibiotic resistance among common gram negative bacteria cause a significant concern specially in India and all over the world because of high mortality and morbidity rates. MethodsIn our study, we screened 189 bacterial isolates from Assam Medical College & Hospital, Dibrugarh for antibiotic resistance pattern and tried to identify the resistant genes causing responsible for β-lactam and fluoroquinolones resistance. ResultsMore than 80% and 45% strains were resistant to all the 3rd generation cephalosporins, fluoroquinolones respectively. Among the 3rd generation cephalosporin resistant strains, 38% and 24% isolates were only ESBL and MBL producers respectively and 11% were reported to have both ESBL and MBL genes. The ESBL positive isolates have shown the dominance of CTX-M3 gene. VIM-1 gene was mostly reported in MBL producers. Our study probably for the first time reporting SIM-1 and SPM-1 MBL gene from India. Mutations in QRDR is found to be the primary cause of fluoroquinolone resistance along with efflux pump and PMQR presence. ConclusionThe study represents the first detailed study on antibiotic resistance from NE India this could help to take control measures for the emerging antibiotic resistance in hospital and community based infections in North East India.

Sensitivity Patterns of Isolated Salmonella Typhi in Children with Typhoid Fever

<i>Background and objective</i>: Enteric fever is a common febrile illness and one of te major health problem in Bangladesh. So the present study was conducted to determine the demographic characteristics, clinical profile, hematological feature and current sensitivity patterns of isolated S typhi in patients suffering from enteric fever in some of the tertiary care hospitals in Dhaka. <i>Materials & Methods</i>: This was a cross sectional study conducted in the Department of Pediatrics, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka Medical College Hospital (DMCH) and SSMCH – Sir Salimullah Medical College & Hospital (SSMCH), Dhaka, Bangladesh for a period of one year from July 2015 to June 2016. A total number of 100 children with enteric fever were studied and diagnose were based on clinical features, Wedel test and blood culture. <i>Results</i>: Out of 100 diagnosed enteric fever children, 60 (60%) were male and 40 (40%) were female. Fever was present in all patients. Other most common manifestation are loss of appetite, vomiting, diarrhea, headache and constipation. Coated tongue was the predominant examination finding followed by hepatomegaly, splenomegaly and abdominal tenderness. Sensitivity to ceftriaxone was 100% in our study while resistance to nalidixic acid was 90%. MDR S.typhi is still a threat but there was re-emergence of sensitivity to Cotrimoxazole and Chloramphenicol. <i>Conclusion</i>: The study concluded that clinical pattern of typhoid fever conforms well to that of known pattern of the disease in children. Blood culture profile shows widespread emergence of nalidixic acid related resistant strains and the sporadic occurrence of cephalosporin resistant strains of S. Typhi. However, the first line antibiotics such as chloramphenicol and cotrimoxazole still have a role to play in the treatment of typhoid due to re-emergence of sensitivity.