Continuous Surveillance Of Antimicrobial Resistance Research Articles

Molecular Prevalence of MecA and MecC Genеs in Coagulasе-Positive Staphylococci Isolated From Dogs with Dermatitis and Otitis in Belgrade, Serbia: A One Year Study

Abstract The escalating global concern of antimicrobial resistance in human and veterinary medicine is exacerbated by the inappropriate prescription of antibiotics for bacterial infections in companion animals. This study aimed to determine the distribution of coagulase-positive staphylococci causing clinical skin and ear infections in dogs and to determine methicillin-resistant isolates. A total of 78 staphylococcal strains were isolated from clinical samples taken from patients at the Dermatology Clinic at the Faculty of Veterinary Medicine in Belgrade, Serbia. Multiplex PCR was used for species-specific identification, and mecA and mecC genes were used to determine methicillin resistance, in addition to phenotypic determination, MIC values and detection of PBP2a. Out of the 78 samples analyzed, 65.8% were identified as Staphylococcus pseudintermedius, 22.4% as S. aureus, 7.9% as S. coagulans, and 3.9% as S. intermedius. Four S. aureus isolates exhibited methicillin resistance confirmed by cefoxitin disk diffusion, while five were confirmed with MIC testing and latex agglutination. MecA gene was detected in 29.4% of S. aureus and 30% of S. pseudintermedius isolates. These isolates were classified as methicillin-resistant S. aureus (MRSA) and methicillin-resistant S. pseudintermedius (MRSP), respectively. No isolates carried the mecC gene. This study provides insights into the prevalence of CoPS species and methicillin resistance in isolates from dogs. Continued surveillance is essential to monitor and understand the emergence and dissemination of antimicrobial resistance in veterinary medicine and the results of this study accent the need for establishment of a continuous antimicrobial resistance surveillance program in the Republic of Serbia.

The current spectrum of infections in cancer patients with chemotherapy related neutropenia

Background: New cancer treatments have improved patient survival but also bring side effects like weakened immunity and higher infection risk. The present study aimed to assess the pattern of blood stream infections and antimicrobial resistance in blood isolates of neutropenic patients. Material and Methods: This Cross-sectional, observational study was conducted at Department of Oncology, Jinnah Postgraduate Medical Centre, Karachi, Pakistan between August 2019 to August 2020. Malignant patients who underwent chemotherapy and presented with fever, neutropenia, and positive bacterial blood culture were enrolled in the study. Patients with a recent history of blood transfusion were excluded. The spectrum of bacterial infections and the antimicrobial resistance patterns of causative organisms isolated from blood were studied. The CLSI standard antimicrobial panel was used for each microorganism. Findings were presented in tabular form. Results: During the study period 95 organisms were isolated from the blood cultures. Strains of E. Coli, Klebsiella, Pseudomonas, S. Aureus, S. Pneumoniae, were found in 27 (28.4%), 18 (18.9%), 13 (13.7%), 17 (17.9%), and 2 (2.1%) patients, respectively. 44.0% of E. coli, 68.8% of Klebsiella, and 38.5% of Pseudomonas were resistant to tazobactam. 92.6% of E. coli, 88.2% of Klebsiella, 100% of Pseudomonas were resistant to Co-amoxiclav. 52.9% of Staph aureus were resistant to methicillin. 23 (92.0%) strains of E. coli, 15 (83.3%) strains of Klebsiella, 6 (46.2%) strains of Pseudomonas, and 11 (68.8%) of Staph aureus were resistant to ciprofloxacin. Conclusion: Resistance to the majority of the commonly used antimicrobial drugs was noted. Continuous antimicrobial resistance surveillance of the everchanging spectrum of causative organisms and their characterization is very important to treat the bloodstream infections (BSI) in cancer patients with chemotherapy induced neutropenia. Keywords: Neutropenia Infection, Fever, Antimicrobial resistance, Chemotherapy.

Study of bacterial respiratory infections and antimicrobial susceptibility profile among antibiotics naive outpatients visiting Meru teaching and referral hospital, Meru County, Kenya in 2018

ObjectiveRespiratory tract infections cause significant morbidity and mortality globally and are the most common infectious diseases in humans. This study aims at assessing the presence of bacterial respiratory infections, number of people infected and antimicrobial susceptibility profile among antibiotic naïve outpatients presenting with respiratory tract infections in Meru Teaching and Referral Hospital.MethodsThe study was conducted in Meru Teaching and Referral Hospital, Meru County from April 2017 to August 2018. Upper respiratory infections were characterized by acute infection of nasal cavity, pharynx and larynx while lower respiratory infections were characterized by chest pains, prolonged cough, productive sputum, difficulty in breathing, fever and weight loss. A total of 384 sputum and throat samples were collected aseptically from patients who were clinically suspected to have respiratory infections and cultured in blood agar, MacConkey agar and chocolate agar. Bacterial isolates were identified by colonial morphology, Gram stain and confirmed by biochemical tests. Antimicrobial susceptibility profile was determined using agar disc diffusion method.ResultsRespiratory bacterial pathogens were isolated in 45.6% of the samples. The prevalence of the bacteria species isolated were as follows Pseudomonas species (36.6%), Klebsiella species (20.6%), Staphylococcus aureus (16.6%), Streptococcus pyogenes (13.7%), Streptococcus pneumoniae (10.3%) and mixed isolates (2.3%). Amoxicillin and ampicillin recorded the highest resistance rate. Most of the isolates displayed high level of resistance to more than two antibiotics. Although multidrug resistance is reported in the study, gentamicin, amikacin and cefuroxime are recommended as the antibiotics of choice against bacterial isolates obtained.ConclusionBacterial respiratory infections were prevalent in the study area and the isolates obtained showed resistance to commonly used antibiotics such as amoxicillin, ampicillin, ciprofloxacin piperacillin ciprofloxacin, ceftazidime, piperacillin-tazobactam and cephalexin. Therefore need for a continuous surveillance of antimicrobial resistance in management of respiratory infections in the study area.

Predominance of multidrug-resistant bacteria causing urinary tract infections among men with prostate enlargement attending a tertiary hospital in Dar es Salaam, Tanzania

BackgroundPatients with prostate enlargement have an increased risk of recurrent urinary tract infections. This study determined the resistance profile of bacteria causing urinary tract infection (UTI) and the magnitude of multidrug-resistant (MDR) bacteria among patients with symptomatic prostate enlargement in a tertiary hospital in Dar es Salaam.MethodsThis cross-sectional study was conducted at Muhimbili National Hospital between August 2021 and January 2022. Male patients aged 40–90 years with symptomatic enlarged prostate, confirmed by digital rectal examination, were enrolled consecutively. We used conventional biochemical methods and analytical profile index (API) 20-E & API 20-NE to identify the uropathogens. In addition, antimicrobial susceptibility testing was performed using the Kirby–Bauer disc diffusion method.ResultsA total of 422 participants were enrolled, of whom 196 (46.4%) had laboratory-confirmed UTI. In total, 203 bacterial pathogens were isolated. Gram-negative bacteria (GNB) were the predominant uropathogens accounting to 165/203 (81.3%). The prevalent isolates were E. coli 49 (24.1%), followed by K. pneumoniae 40 (19.7%). Most, 157 (77.3%) pathogens were MDR, of which 33 (21.0%) were resistant to all tested antibiotic classes. The proportion of methicillin-resistant Staphylococcus aureus was 75.8%, while 45.5% of S. aureus were inducible clindamycin resistant. Among Enterobacterales, 98 (70.5%) were Extended-spectrum beta-lactamases (ESBL) producers, and 33 (20.0%) were carbapenem resistant. Four of forty-one (9.6%) non-ESBL producers were class C β-lactamase producers.ConclusionsThere is a relatively high proportion of MDR strains of uropathogens, which limits treatment options for UTI among men with prostate enlargement. These findings call for the revision of the current UTI treatment guidelines and continuous antimicrobial resistance surveillance to monitor antibiotic resistance and guide treatment options within the hospital.

Prevalence of Multidrug-Resistant, Extensively Drug-Resistant and Pandrug-Resistant <i>Pseudomonas </i><i>a</i><i>eruginosa</i> Clinical Isolates in Khartoum State, Sudan

Background. Pseudomonas aeruginosa is a common opportunistic Gram-negative pathogen responsible for a wide range of hospital acquired infections that may present high rates of antimicrobial resistance. It could also become multidrug-resistant (MDR), extensively drug-resistant (XDR), and pan drug-resistant (PDR) during a short period. The aim of the present study is to determine the prevalence of MDR, XDR and PDR-P. aeruginosa clinical isolates in Khartoum State-Sudan. Materials and Methods. A multihospital laboratory-based study was conducted to collect P. aeruginosa clinical isolates from various clinical specimen’s culture during eighteen-month period from March 2020 to December 2021. The P. aeruginosa strains were reidentified by conventional biochemical methods and genotypically by amplification of 16S rRNA gene by Polymerase chain reaction (PCR) assay. Antimicrobial susceptibility testing was done by Kirby-Bauer disc diffusion method. MDR, XDR and PDR were determined according to new recommendation of the Clinical and Laboratory Standards Institute and the European Committee for Antimicrobial Susceptibility Testing. Results. Of 512 P. aeruginosa clinical isolates were recovered from various clinical specimen’s culture, only 289 (66.4%) of the isolates were confirmed as P. aeruginosa strains genotypically, out of those P. aeruginosa strains were categorized regarding antimicrobial resistance to 98 (33.9%) MDR, 61 (21.1%) XDR and 2 (0.7%) PDR. The XDR strains were exhibited significant overall resistance to all used antibiotic classes, whereas MDR strains were insignificant resistant to fluoroquinolones and polymyxins. Patients prior of hospitalized for 1-2weeks, uses of companied antibiotics therapy with duration of one week and source of isolation from wound swab and blood specimen (P P. aeruginosa isolates. Conclusion. The study highlights the increase prevalence of MDR and XDR P. aeruginosa clinical isolates in both hospital and community settings, along with emerged two pandrug resistant strains. Thus, continuous antimicrobial resistance surveillance for this bacterium is necessary for guiding antimicrobial treatment and stewardship as well as based knowledge for future comparative studies.

Surveillance and molecular epidemiology of Neisseria gonorrhoeae isolates in Shenzhen, China, 2010–2017

ObjectivesThe development and emergence of antimicrobial resistance in Neisseria gonorrhoeae (NG) have become a major public-health problem worldwide. This study aimed to analyse the antimicrobial susceptibility and molecular characteristics of NG isolates in Shenzhen, China. MethodsA total of 1282 NG isolates were consecutively collected between 2010 and 2017. Patient demographic information was also collected. MICs of ceftriaxone, spectinomycin, ciprofloxacin, azithromycin and penicillin were determined by agar dilution. Isolates were genotyped using N. gonorrhoeae multi-antigen sequence typing (NG-MAST). ResultsAmong the isolates, 97.4% were resistant to ciprofloxacin and 68.2% to penicillin. Moreover, 5.0% showed decreased susceptibility to ceftriaxone (CROD) and 17.3% were resistant to azithromycin (AZM-R); 1.3% were simultaneously CROD and AZM-R. All isolates were susceptible to spectinomycin. Increasing ceftriaxone MICs were found from 2010 to 2017. A total of 427 sequence types (STs) and 68 genogroups were identified from 724 isolates. ST5061, ST3741 and ST1766 were observed across the study years. ST14638 (n = 3) was predominant among 32 CROD isolates. Prevalent STs were ST5061 (n = 6), ST1866 (n = 5) and ST11133 (n = 5) among 96 AZM-R isolates. ConclusionsA high prevalence of isolates resistant to ciprofloxacin and penicillin was found in this study. Azithromycin, one antimicrobial of dual antimicrobial therapy recommended by the WHO, showed a high prevalence of resistance. The other, ceftriaxone, can be used continuously in this region owing to lower resistance levels. However, the emergence of CROD and decreasing susceptibility to ceftriaxone indicate that continuous antimicrobial resistance surveillance is essential.

Multidrug-resistant and extended-spectrum beta-lactamase-producing uropathogens in children in Bhaktapur, Nepal

BackgroundThe emergence of multidrug-resistant (MDR) and extended-spectrum beta-lactamase (ESBL)-producing uropathogens has complicated the treatment of urinary tract infections (UTI). Paediatric UTI is a common illness, which if not treated properly, may lead to acute and long-term complications, such as renal abscess, septicaemia, and renal scarring. This study aimed to determine the prevalence of MDR and ESBL-producing uropathogens among children.MethodsDuring the study period (April 2017–April 2018), midstream urine samples were collected following aseptic procedures from children < 16 years in Siddhi Memorial Hospital. Standard culture and biochemical tests were performed to identify uropathogens and antimicrobial susceptibility test was done by modified Kirby-Bauer disc diffusion method following Clinical and Laboratory Standard Institute (CLSI) guidelines. ESBL-producing uropathogens were screened by ceftazidime (30 μg) and cefotaxime (30 μg) discs, and confirmed by the combination disc tests: ceftazidime + clavulanic acid (30/10 μg) or cefotaxime + clavulanic acid (30/10 μg) as recommended by CLSI.ResultsWe processed 5545 non-repeated urine samples from the children with symptoms of UTI. A significant growth of uropathogens was observed in 203 samples (3.7%). The median age of the children was 24 months (interquartile range (IQR), 12–53 months). Escherichia coli (n = 158, 77.8%) and Klebsiella pneumoniae (n = 30, 14.8%) were common among the uropathogens. Among them, 80.3% were resistant to amoxycillin and 51.2% were resistant to cotrimoxazole. Most of them were susceptible to amikacin, nitrofurantoin, and ofloxacin. MDR was detected in 34.5% (n = 70/203) and ESBL producers in 24.6% (n = 50/203) of them. The proportion of MDR isolates was higher in children < 5 years (n = 59/153, 38.6%) than children ≥ 5 years (n = 11/50, 22%) (P = 0.03).ConclusionsNitrofurantoin, ofloxacin, and amikacin can be used for the empirical treatment for UTI in children in Bhaktapur, Nepal. MDR and ESBL-producing uropathogens are prevalent; this warrants a continuous surveillance of antimicrobial resistance.

Long-Term Continuous Antimicrobial Resistance Surveillance Among Nosocomial Gram-Negative Bacilli in China from 2010 to 2018 (CMSS).

PurposeThe Chinese Meropenem Surveillance Study (CMSS) was conducted every 2 years from 2010 to 2018 to monitor the antimicrobial activity of commonly used antimicrobial agents against nosocomial gram-negative bacilli in China.MethodsFrom 2010 to 2018, 6,537 gram-negative bacilli were collected from 14 teaching hospitals. The minimum inhibitory concentrations (MICs) of meropenem and other antimicrobial agents were determined using the agar dilution and broth microdilution methods.ResultsContinuous surveillance indicated that, except for Klebsiella pneumoniae, the susceptibility of Enterobacterales to carbapenems was relatively stable over time. Carbapenems had the highest activity against the tested isolates, with MIC90 values (MIC for 90% of organisms) ranging from 0.032 mg/L to 8 mg/L. More than 90% of bacteria were susceptible to either meropenem or imipenem; more than 80% were susceptible to ertapenem. The prevalence of extended-spectrum beta-lactamase (ESBL)-producing E. coli, K. pneumoniae, and P. mirabilis each year was 50.4–64.3%, 18–41.2%, and 1.9–33.8%, respectively. The prevalence of carbapenem-resistant K. pneumoniae (CRKP) and carbapenem-resistant Acinetobacter baumannii (CRAB) continued to increase significantly over time, from 7.6% to 21.2% and 64.6% to 69.3%, respectively. The prevalence of CRKP was higher from urinary tract infections (25.4%) than from bloodstream infections (14.2%), intra-abdominal infections (14.5%), and respiratory infections (14.4%). In total, 129 CRKP isolates were evaluated by PCR; of these, 92 (71.3%) carried the blaKPC-2 gene. Colistin maintained very high in vitro antimicrobial activity against P. aeruginosa and A. baumannii (more than 95% of isolates exhibited susceptibility at all timepoints).ConclusionThe results indicate an increase in K. pneumoniae resistance to carbapenems over time, mainly owing to KPC-type carbapenemase production. A. baumannii was severely resistant to carbapenems in China. Ongoing MIC-based resistance surveillance, like CMSS, provides additional data for clinical anti-infective treatment.

Prevalence and trend analysis of antimicrobial resistance in clinical Escherichia coli isolates collected from diseased pigs in the USA between 2006 and 2016.

Antimicrobial resistance (AMR) is an emerging threat to both human and animal health. Antimicrobial use and resistance in food animal production, including swine, has received increased scrutiny as a source of resistant foodborne pathogens. Continuous surveillance of AMR in bacterial isolates of swine origin can guide in conservation of antimicrobials used in both human and swine medicine. The objective of this study was to evaluate the prevalence and trends of the phenotypic AMR in Escherichia coli of swine origin isolated from clinical samples at the Minnesota Veterinary Diagnostic laboratory between 2006 and 2016. The prevalence of resistance to ampicillin, tetracyclines and sulphadimethoxine remained greater than 50% throughout the period. There was a drastic change in enrofloxacin resistance, increasing from less than 1% to more than 20% between 2006 and 2016 (annual relative increase of 57% between 2006 and 2013 and 16% between 2013 and 2016). The prevalence of resistance to other antimicrobials remained constant (ceftiofur, oxytetracycline and chlortetracycline) or changed significantly (annual relative changes of less than 10%) for at least some time-period between 2006 and 2016 (ampicillin, florfenicol, gentamicin, neomycin, sulphadimethoxine, trimethoprim-sulphamethoxazole and spectinomycin). Rarefaction analysis revealed an increase in the number of unique combinations of AMRs per year. Network analysis was performed by estimating and plotting partial correlations between minimum inhibitory concentrations (MICs) of various antimicrobials. An increase in strength of these networks was observed, particularly in networks created after 2010, which can be indicative of increased multiple AMR in these isolates. These results provide valuable insight into the trends in AMR in E. coli of swine origin in the USA and act as supplementary information to the existing active AMR surveillance systems.

Genotypic Diversity and Characterization of Quinolone Resistant Determinants from Enterobacteriaceae in Yaound&amp;#233;, Cameroon

Background: Enterobacteriaceae causes many types of infections which are often treated with quinolones and fluoroquinolone (Q/FQ). The resistance mechanisms to Q/FQ are usually associated with mutations in the quinolone resistance determining region which alter the conformation of target amino acid residues within the protein and in the qnr genes. This study aimed at determining the antimicrobial resistant profile of a sample of Enterobacteriaceae from Cameroon and the genetic diversity in quinolone-resistant isolates in view of implementing a better management, treatment, control and prevention of the transmission of these resistant strains. Methods: Identification and antimicrobial susceptibility testing was done using VITEK 2. The detection of plamid-mediated quinolone resistance (PMQR) genes was carried out using the conventional PCR method. Sequencing was done using the Applied Biosystem 3500 genetic analyser. DNA fingerprint was obtained using Pulsed-Field Gel electrophoresis. Results: Among 440 Enterobacteriaceae, the most prevalent genera were: Escherichia 178/440 (39.5%); Klebsiella 148/440 (33.6%); Enterobacter 35/440 (8%); Pantoea 28/440 (6.4%); Proteus 14/440 (3.2%) Salmonella 13/440 (3%). Ampicillin resistance showed the highest prevalence with 371/440 (81%) and Imipenem the lowest resistance 9/440 (2.1%). The ciprofloxacin resistance rate was 161/440 (36.6%). The detected plasmid mediated quinolone resistance (PMQR) genes were: qnrA, 2/161 (1.2%); qnrB, 31/161 (19.3%); qnrS, 13/161 (8.1%): Aac (6')Ib-cr, 84/161 (52.2%) and qepA, 3/161 (1.9%). There were several mutations in the parC gene of Klebsiella leading to S80D and S80N substitutions. Two pairs of Klebsiella peumoniae strains were phenotypically and genotypically identical with 100% similarity in the dendrogramme. Conclusion: This study showed that quinolone resistance was high. The PMQR genes contributing to this resistance were diverse. This high PMQR indicates that there has been an unknown circulation of these genes in our community. To avoid the rapid dissemination of these PMQR genes continuous surveillance of antimicrobial resistance should be carried out not only in humans but also in animals to monitor the evolution of these genes.

Incidence and Bacterial Etiologies of Surgical Site Infections in a Public Hospital, Addis Ababa, Ethiopia

Background: Surgical Site Infections (SSIs) are among the frequently reported healthcare-acquired infections worldwide. Successful treatment of SSIs is affected by the continuous evolvement of drug-resistant microbes. This study investigated the incidence of SSIs, identifying the major etiologic agents and their drug resistance patterns in Yekatit 12 Hospital, Ethiopia. Methods: A cross-sectional study was conducted on 649 patients who underwent surgery at Yekatit 12 hospital from April 2016 to April 2017. Socio-demographic and clinical data were collected from each patient on admission. After surgery, they were followed for SSI occurrence. SSI was initially diagnosed by a senior surgeon based on standard clinical criteria and then confirmed by culture. Isolates were tested for drug resistance according to the clinical and laboratory standards institute guideline. Results: Of the 649 study participants, 56% were females. Their age ranged from 9 months to 88 years with a median age of 37 years. The incidence of culture-confirmed SSI was 10.2% (66/649) where 73 isolates were recovered. About two-third of the isolates were Gram-positive bacteria. Staphylococcus aureus was the most frequently isolated (27/73, 37%) followed by Coagulase-negative staphylococci (18/73, 24.7%), Escherichia coli (11/73, 15.1%) and Klebsiella species (10/73, 13.7%). About 89% and 44% of S. aureus isolates were resistant to penicillin and trimethoprim-sulfamethoxazole, respectively. MRSA constituted 11% of the S. aureus isolates. All the Gram-negative isolates were resistant to ampicillin and trimethoprim-sulfamethoxazole but susceptible to amikacin and meropenem. Klebsiella species showed 70-100% resistance to ceftazidime, cefuroxime, augmentin, chloramphenicol, ciprofloxacin, cefepime and gentamicin. About 82% of E. coli isolates were resistant for chloramphenicol, cefepime, ceftazidime, augmentin, cefuroxime and 64% for gentamicin and ciprofloxacin. Conclusion: The incidence of surgical site infection in Yekatit 12 hospital is 10.2%. Most of the SSIs were due to Gram-positive bacteria. Gram-negative isolates showed high resistance to the most commonly prescribed drugs. No resistance was found for meropenem indicating the absence of carbapenem-resistant bacteria. SSI treatments should be guided by culture and drug resistance test. Better infection prevention practices and continuous surveillance of antimicrobial resistance in the hospital are recommended for better patient care.

Monitoring the antimicrobial susceptibility of Gram-negative organisms involved in intraabdominal and urinary tract infections recovered during the SMART study (Spain, 2016 and 2017).

Continuous antimicrobial resistance surveillance is recommended by Public Health authorities. We up-dated data from the SMART (Study for Monitoring Antimicrobial Resistance Trends) surveillance study in Spain. The antimicrobial susceptibility data and extended-spectrum beta-lactamase (ESBL) production in isolates recovered from intra-abdominal (IAI) (n=1,429) and urinary tract (UTI) (n=937) infections during the 2016- 2017 SMART study in 10 Spanish hospitals were analysed. Escherichia coli was the most frequently microorganism isolated (48.3% and 53.7%) followed by Klebsiella spp. (11.5% and 21.9%) in IAIs and UTIs, respectively. Figures for Pseudomonas aeruginosa were 9.0% and 6.1%, being more frequently recovered from patients with nosocomial infections. Overall, 9.9% (IAI) and 14.0% (UTI) of E. coli, Klebsiella spp. and Proteus mirabilis isolates were ESBL-producers, being Klebsiella pneumoniae (34.5%) from UTI of nosocomial origin the most frequent. ESBL-producers were higher in patients >60 years in both IAIs and UTIs. As in previous years, amikacin (96.3%-100% susceptibility), ertapenem (84.2%-100%) and imipenem (70.3%- 100%) were the most active antimicrobials tested among Enterobacterales species. The activity of amoxicillin-clavulanic, piperacillin-tazobactam, and ciprofloxacin susceptibility was lower, particularly among ESBL-producers. Ertapenem susceptibility (88.9%-100%) was retained in ESBL-E. coli isolates that were resistant to these antimicrobials but decreased (28.6%-100%) in similar isolates of K. pneumoniae. Continuous antimicrobial resistance surveillance from the SMART study reveals overall maintenance of ESBL-producers in Spain, although with higher presence in isolates from UTIs than from IAIs. Moreover, ertapenem activity was high in E. coli irrespective of ESBL production but decreased in K. pneumoniae, particularly among ESBL-producers.

Antimicrobial resistance patterns of uropathogens isolated between 2012 and 2017 from a tertiary hospital in Northern Ethiopia.

Urinary tract infections (UTIs) are one of the most common infections in humans. Studies have shown that antibiotics for UTIs are usually prescribed empirically before the results of urine culture are available. The aim of the study was to assess the antimicrobial resistance patterns of bacteria isolated from urine samples over 6 years in Ayder Comprehensive Specialized Hospital (ACSH), in Mekelle, Northern Ethiopia. A retrospective study of culture results of UTI samples was conducted in ACSH from January 2012 to December 2017. Data were collected using a structured data sheet format and were analysed using SPSS v.20.0. Among 1080 urine samples tested during the 6-year period, 308 (28.5%) were positive for bacterial isolates. The majority of participants were female (57.8%). The three most commonly isolated bacteria were Escherichia coli (48.1%), Klebsiella pneumoniae (16.2%) and Pseudomonas aeruginosa (6.5%). Escherichia coli was found to be most susceptible to imipenem (100%) and most resistant to ampicillin (94.9%). Similarly, K. pneumoniae was sensitive to meropenem (100%) but resistant to penicillin (100%). Multidrug resistance to two or more antimicrobials was observed in 267 isolates (86.7%), with a non-significantly higher prevalence in females (χ2=9.65, P=0.29). The overall pooled bacterial resistance was 57.8%. This study revealed that most of the urine isolates showed high levels of antimicrobial resistance to commonly prescribed antibiotics although they remained susceptible to imipenem, nitrofurantoin and meropenem. The results call for continuous surveillance of antimicrobial resistance for better management of patients with UTIs.

Detection of oxazolidinone and phenicol resistant enterococcal isolates from duck feces and carcasses

The heavy use or abuse of antimicrobials in food animals has caused an increase in antimicrobial resistance in enterococci of animal origin, which could get transmitted to those of human origin via the food chain. Since duck meat consumption has been on the rise in Korea, we conducted this study to provide information about the antimicrobial resistance of the enterococci obtained from healthy ducks and their carcasses. A total of 82 Enterococcus faecium and 174 E. faecalis isolated from duck fecal and carcass samples were investigated for antimicrobial resistance to 16 agents, using broth dilution method, and were further characterized using molecular methods. Most of E. faecium (84.1%) and E. faecalis (87.9%) isolates were resistant to one or more antimicrobials. Multi-drug resistant (MDR) isolates were observed in both E. faecium (40.2%) and E. faecalis (33.9%) with high frequencies. High rate of resistance was observed for tetracycline, ciprofloxacin, chloramphenicol, and erythromycin in both E. faecium and E. faecalis. Resistance to gentamicin, vancomycin, and daptomycin, in both E. faecium and E. faecalis, was, if at all, very rare. However, linezolid resistance was observed in nine E. faecium (11.0%) and one E. faecalis (0.6%). All, but one, Linezolid resistant (LR) isolates were also resistant to chloramphenicol and florfenicol. The novel transferable oxazolidinone and phenicol resistant gene, optrA, was found in six E. faecium isolates. All of them co-carried phenicol exporter gene fexA. None of the LR isolates had mutation in the 23S ribosomal RNA and in the ribosomal protein L3. Six LR E. faecium isolates had Asn130Lys mutation in the ribosomal protein L4, of which five also carried optrA gene. None of the isolates carried the multi-resistance gene cfr. Transfer of oxazolidinone and phenicol resistance was observed in five among the 10 LR isolates; two of them had optrA and fexA genes. Multi-drug resistant Enterococcus that also carried the resistance gene to a last-resort antimicrobial is a major concern for public health. Thus, to prevent the introduction of last-resort antimicrobial resistance into food chain, continuous surveillance of antimicrobial resistance in duck is imperative.

Antimicrobial susceptibility pattern of Acinetobacter isolates from patients in Kenyatta National Hospital, Nairobi, Kenya.

IntroductionInfection due to multidrug-resistant microorganisms is a growing threat in healthcare settings. Acinetobacter species specifically A. baumannii is increasingly becoming resistant to most antimicrobial agents recommended for treatment. This study aimed to determine the antimicrobial susceptibility pattern of Acinetobacter species isolated from patients in Kenyatta National Hospital.MethodsWe conducted a retrospective study based on VITEK 2 (BioMérieux) electronic records capturing identification and antimicrobial susceptibility of Acinetobacter isolates from patient samples analyzed between 2013 and 2015 at Kenyatta National Hospital microbiology laboratory. Generated data were analyzed using WHONET and SPSS.ResultsA total of 590 Acinetobacter isolates were analyzed. 85% of the isolates tested were multi-drug resistant (MDR). Among the 590 isolates, 273 (46%) were from tracheal aspirates and 285 (48%) from the critical care unit. A. baumannii was the most frequently isolated species with high susceptibility to amikacin (77%) and poor susceptibility to ciprofloxacin (69-76%), tobramycin (37%) and meropenem (27%). Both A. lwoffii and A. haemolyticus had high susceptibility to amikacin (80-100%) and meropenem (75-100%).ConclusionA. baumannii is resistant to commonly administered antibiotics. There is need for continuous antimicrobial resistance surveillance especially in health care facilities and strengthening of antibiotic stewardship programmes which will contribute to enhancement of infection control policies.

Towards national systems for continuous surveillance of antimicrobial resistance: Lessons from tuberculosis.

In a Perspective on the research article from Jacobson and colleagues, Amitabh Suthar and colleagues from the Centers for Disease Control and Prevention discuss the importance of and considerations for developing real-time and large-scale reporting systems for tracking and controlling antimicrobial resistance.

Epidemiology and molecular characterization of multidrug-resistant Escherichia coli isolates harboring blaCTX-M group 1 extended-spectrum β-lactamases causing bacteremia and urinary tract infection in Manhiça, Mozambique.

BackgroundThe emergence and spread of extended-spectrum β-lactamases (ESBLs), especially CTX-M, is an important public health problem with serious implications for low-income countries where second-line treatment is often unavailable. Knowledge of the local prevalence of ESBL is critical to define appropriate empirical therapeutic strategies for multidrug-resistant (MDR) organisms. This study aimed to assess and characterize the presence of ESBL and especially CTX-M-producing Escherichia coli MDR isolates from patients with urinary tract infections (UTIs) and bacteremia in a rural hospital in Mozambique.Materials and methodsOne hundred and fifty-one E. coli isolates from bacteremia and UTI in children were screened for CTX-M, TEM, SHV and OXA β-lactamases by polymerase chain reaction and sequencing. Isolates carrying CTX-M group 1 β-lactamases were further studied. The resistance to other antibiotic families was determined by phenotypic and genotypic methods, the location of the blaCTX-M gene and the epidemiology of the isolates were studied, and extensive plasmid characterization was performed.ResultsApproximately 11% (17/151) of E. coli isolates causing bacteremia and UTI were ESBL producers. CTX-M-15 was the most frequently detected ESBL, accounting for 75% of the total isolates characterized. The blaCTX-M gene is located in different plasmids belonging to different incompatibility groups and can be found in non-epidemiologically related isolates, indicating the high capacity of this resistance determinant to spread widely.ConclusionOur data suggest the presence of a co-selection of third-generation cephalosporin-resistant determinants in the study area despite limited access to these antibiotics. This highlights the importance of continuous surveillance of antimicrobial resistance of both genetic elements of resistance and resistant isolates in order to monitor the emergence and trends of ESBL-producing isolates to promote adequate therapeutic strategies for the management of MDR bacterial infections.

Results from the Survey of Antibiotic Resistance (SOAR) 2014-16 in the Czech Republic.

To determine the antibiotic susceptibility of isolates of Streptococcus pneumoniae and Haemophilus influenzae collected in 2014-16 from patients with community-acquired respiratory infections in the Czech Republic. MICs were determined by CLSI broth microdilution and susceptibility was assessed using CLSI, EUCAST and pharmacokinetic/pharmacodynamic (PK/PD) breakpoints. S. pneumoniae isolates (n = 200) showed high rates of susceptibility (>95%) to amoxicillin, amoxicillin/clavulanic acid, penicillin [intravenous (iv) non-meningitis], ceftriaxone, cefuroxime and the fluoroquinolones using CLSI breakpoints. Susceptibility to cefaclor and trimethoprim/sulfamethoxazole was 94%-94.5%, to penicillin (oral) 91.5% and to the macrolides 89.5%. Susceptibility of H. influenzae (n = 197) to amoxicillin/clavulanic acid, ceftriaxone, cefuroxime, azithromycin and the fluoroquinolones was ≥98% by CLSI criteria. Rates of susceptibility to the remaining agents were ≥75% except for clarithromycin at 37.1%. Great variability was seen across breakpoints, especially for the macrolides, cefaclor and cefuroxime (oral), 98.0% of H. influenzae showing susceptibility to the latter by CLSI criteria, 69.5% by PK/PD and 1.5% by EUCAST standards. The β-lactamase rate was 13.7% with no β-lactamase-negative-ampicillin-resistant (BLNAR) isolates by CLSI criteria. Antibiotic resistance among the two major respiratory pathogens remained low in the Czech Republic. These findings support local clinicians in continuing the historically restrictive use of antibiotics in the Czech Republic, with selection of narrower-spectrum agents for the empirical therapy of community-acquired respiratory tract infections. This highlights one of the great benefits of continuous surveillance of antimicrobial resistance: knowledge of current local resistance patterns reduces the need to choose broad-spectrum agents that contribute to increasing resistance worldwide.

Characterization and Antimicrobial Resistance of Salmonella Typhimurium Isolates from Clinically Diseased Pigs in Korea

This study investigated the prevalence of Salmonella enterica serovar and antimicrobial resistance in Salmonella Typhimurium isolates from clinically diseased pigs collected from 2008 to 2014 in Korea. Isolates were also characterized according to the presence of antimicrobial resistance genes and pulsed-field gel electrophoresis patterns. Among 94 Salmonella isolates, 81 (86.2%) were identified as being of the Salmonella Typhimurium serotype, followed by Salmonella Derby (6 of 94, 6.4%), Salmonella 4,[5],12:i:- (4 of 94, 4.3%), Salmonella Enteritidis (2 of 94, 2.1%), and Salmonella Brandenburg (1 of 94, 1.1%). The majority of Salmonella Typhimurium isolates were resistant to tetracycline (92.6%), followed by streptomycin (88.9%) and ampicillin (80.2%). Overall, 96.3% of Salmonella Typhimurium isolates showed multidrug-resistant phenotypes and commonly harbored the resistance genes blaTEM (64.9%), flo (32.8%), aadA (55.3%), strA (58.5%), strB (58.5%), sulII (53.2%), and tetA (61.7%). The pulsed-field gel electrophoresis analysis of 45 Salmonella Typhimurium isolates from individual farms revealed 27 distinct patterns that formed one major and two minor clusters in the dendrogram analysis, suggesting that most of the isolates (91.1%) from diseased pigs were genetically related. These findings can assist veterinarians in the selection of appropriate antimicrobial agents to combat Salmonella Typhimurium infections in pigs. Furthermore, they highlight the importance of continuous surveillance of antimicrobial resistance and genetic status in Salmonella Typhimurium for the detection of emerging resistance trends.

Molecular characterization of multidrug resistant Salmonella from chicken and human in Yaounde

Salmonella is one of the most common foodborne pathogens worldwide and chicken has been recognized as its main reservoir for human. The aim of this study was to investigate the occurrence of antimicrobial resistance genes in Salmonella isolates from chicken and human, and evaluate their genetic relationship. A total of 200 Salmonella strains (103 from Chicken and 97 from humans) were collected from 2006 to 2007 in Yaounde, and characterized for their antimicrobial susceptibility to a panel of 16 antimicrobials. Presence of antimicrobial resistance genes, class1 and class 2 integrons was investigated by PCR in Multidrug Resistant (MDR) isolates. Pulsed-Field Gel Electrophoresis (PFGE) analysis was used to investigate their genetic relatedness. Only serotypes Enteritidis, Hadar, Bareilly and II were recovered from both chicken and human. Overall, 16 isolates (8%) were susceptible to all antimicrobials including third generation cephalosporins and fluoroquinolons. Resistance was mostly observed to tetracycline (57%) in chicken isolates and to sulfonamides (78.3%) in human isolates. 78 (15.3%) strains were MDR. Class 1 integron was predominant in MDR Hadar and Typhimurium isolates. TEM-1 was the unique Extended Spectrum β-lactamase (ESBL) detected in the β-lactam resistant Typhimurium strain isolated from human. No qnr genes were identified in nalidixic acid resistant isolates. PFGE typing of Enteritidis isolates using XbaI restriction enzyme showed close genetic relationship between chicken and human isolates. For Hadar and Typhimurirum, variety of restriction patterns was observed. These results highlight the need for continuous surveillance of antimicrobial resistance in Salmonella isolates in Cameroon.