Phenotypic Detection of Extended-Spectrum ß-lactamase Produced by Escherichia coli Isolates from Health facilities in Otukpo, Benue State Nigeria

Beta-lactamase production by Escherichia coli and other bacteria is one of the most important mechanism of resistance to beta-lactam antibiotics such as Penicillins and Cephalosporins which are the most commonly used antibiotics in the treatment of bacterial infections in Hospitals. Resistance to antibiotics is emerging worldwide as a threat to human health resulting in limitations of therapeutic options. Susceptibility tests of microorganisms to antimicrobial agents do not reveal production of Extended-Spectrum ß-lactamase, hence the need to detect their presence by phenotypic or molecular techniques. This study is aimed at determining the prevalence of ESBL-production by Escherichia coli isolates from clinical samples collected from some selected health facilities in Otukpo, using phenotypic detection. Four hundred (400) specimens were collected from four different health facilities in Otukpo. Specimens collected included urine, blood, stool and wound swabs from 222 females and 178 males. Standard microbiological methods were employed for isolation, identification and characterization of Escherichia coli isolates from these specimens. Antibiotic susceptibility of the E. coli isolates was determined using Kirby-Bauer disc diffusion method while double disc synergy test (DDST) was used for ESBL production. Sixty-eight, (17%) of the 400 specimens tested for ESBL production were positive. Isolates from stool 22(22.7%) had the highest prevalence of ESBL-producing E. coli, followed by isolates from blood 4(21.4%). Urine isolates had the least prevalence 31(13.8%). Isolates from female subjects, 38(17.1%) had higher positivity rate than their male counterpart 30(16.9%). Otukpo General Hospital had the highest prevalence 20(20.0%) of ESBL followed by Otia Hospital 18(18.0%). Comprehensive health center, Otukpo had the least prevalence 14(14.0%). There is a high prevalence of ESBL production by Escherichia coli isolated from health facilities in Otukpo. Routine drug resistance surveillance therefore has become necessary to guide the appropriate and judicious antibiotic use.

Antimicrobial Susceptibility Pattern of Bacterial Isolates from Surgical Site Infections in a Tertiary Care Hospital

Background Surgical site infections are ranked among the most common health care associated infections. They cause significant morbidity, increased cost of care and prolonged hospital stay. A spectrum of microorganisms with varied antimicrobial susceptibility patterns have been identified as causative agents of SSI which vary with time, hospital, and with the type of surgical procedure performed. We conducted this study with an objective to assess the burden of SSI, its causative aerobic bacteria and their in vitro antibiotic susceptibility patterns. Aims & objectives 1) To identify the aerobic bacteriological profile of isolates causing surgical site infections. 2) To determine the antibiotic sensitivity pattern of the isolates. Method: This study includes 266 clinically diagnosed cases of SSIs over a period of 8 months. Isolates were identified by conventional methods. Isolates of Staphylococcus aureus were tested for methicillin resistance by cefoxitin. Isolates of Escherichia coli and Klebsiella pneumoniae which showed resistance to cefotaxime and ceftazidime were tested for ESBL production by CLSI guidelines. Isolates of Pseudomonas aeruginosa were screened for MBL production using Imipenem disc diffusion test. Results of the 266 samples processed, 193(72.5%) were culture positive samples which yielded 204 isolates. Staphylococcus aureus 60 (29.4%) was found to be the predominant organism causing SSI followed by Pseudomonas aeruginosa 40 (19.6%). Methicillin resistance was observed in 12 (20%) of Staphylococcus aureus strains. ESBL production was observed in 20.5% of Klebsiella pneumoniae isolates and 13.2 % Escherichia coli isolates. MBL production was not seen Pseudomonas aeruginosa isolates. Conclusion: The present study showed the commonest bacteria responsible for the surgical site infections like Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. Hence Implementation of an effective infection control programme and judicious use of antibiotic prophylaxis reduces the incidence of SSI in the hospital.

1438. Prevalence and Risk Factors for Extended Spectrum Betalactamases Among Hospitalized Patients with Community Acquired Pyelonephritis in Colombia

Background Urinary tract infections (UTI) are the most frequent bacterial infection in hospitalized patients. Extented spectrum betalactamases (ESBL) producing bacteria causing UTI have become more prevalent. Escherichia coli (E. coli) is the most frequent ESBL producing bacteria isolated in UTI. This drug resistant organisms are associated with poorer outcomes for patients. In low income countries, approaching to and treating ESBL E. coli, represent a major challenge for health care centers. Methods A retrospective cohort of adult patients with community acquired pyelonephritis caused by Escherichia coli was identified in a tertiary hospital in Colombia. Susceptibility was performed with Vitek (BioMerieux, France); extended spectrum beta lactamase (ESBL) production was defined phenotypically. Inclusion criteria were adult patients hospitalized with a positive urine culture for E. coli. Demographic and clinical characteristics were searched in electronic records. Risk factors associated with ESBL production were identified by using a multivariate logistic regression analysis. Results During 7 years 817 patients with pyelonephritis caused by E. coli were identified. 79 (9.7%) of them were caused by ESBL producers. Women were 66% and 408 (74.8% of them) had menopause. Mean age was 64.2 years (standard deviation of 19.1). Of the cohort, 481 (561.1%) had at least some comorbidity and was frequent to find diabetes (18.5%), immunosuppression due to oncologic disease or medications (18.4%), urolithiasis or previous surgical procedures (17%). After logistic regression, risk factors identified to predict ESBL production, were: being a man (aOR 5.4, 2.1-18.2), a woman with menopause (aOR 2.9, 1.3 -9.9), and the Charlson score (aOR 0.83, 0.73 – 0.96). Previous antibiotic use was not related to ESBL infection. Conclusion In this relatively large cohort of patients with pyelonephritis caused by E. coli, ESBL production risk factors were not clearly identified other than sex and menopause. Curiously, Charlson score predicted a lower risk of resistance. Other factors (food consumptions and others) might be driving the resistance in the community in E. coli. Disclosures Jorge Cortes, MD, Pfizer (Research Grant or Support)

Antibiotic resistance and ESBL production in Escherichia coli from various sources in Aba metropolis, Nigeria

Background The increase in multidrug resistance (MDR) among pathogenic bacteria responsible for infectious diseases has led to lack of effectiveness of some antibiotics. The ability of Escherichia coli to harbor resistant genes has made the treatment of infections a major challenge. This study was carried out to assess antibiotic resistance and extended-spectrum beta-lactamase (ESBL) production of E. coli from various sources in Aba metropolis, Nigeria. Results From a total of 350 samples collected from clinical and non-clinical sources, 137 were presumptively identified as E. coli by standard phenotypic methods and 83 were confirmed as E. coli by the detection of E. coli specific 16S rRNA gene fragments. The majority of these isolates (52, 62.7%) were from non-clinical sources. The clinical isolates, however, exhibited a higher level of resistance against 62.5% of tested antibiotics. Both group of isolates exhibited similar levels (58.1% vs 53.9%) of MDR, though. A low rate of ESBL production was observed (1.2%) following phenotypic detection of ESBL-producing abilities using the double-disc synergy test. An assessment of the presence of three beta-lactamase gene genotypes (blaTEM, blaSHV and blaCTX-M) revealed that none of the three predominant ESBL genotypes was identified in this study. Conclusions This study reports high levels of antibiotic resistance in both clinical and non-clinical E. coli isolates. Though higher rates of resistance were observed among the non-clinical isolates, both group of organisms had similar levels of MDR. Strikingly, however, was the low level of ESBL producers detected in this study and the absence of the three main genotypes associated with ESBL production in this study.

Prevalence and molecular characterization of extended spectrum beta-lactamase producing uropathogenic Escherichia coli in a tertiary health care facility in Anambra State, Nigeria

Background: The prevalence of ESBLs-producing Escherichia coli has recently increased worldwide due to the expression of ESBL genes which had led to high rate of multidrug resistance antibiotics. Aim: To determine the antimicrobial susceptibility patterns of E. coli isolates and evaluating the ESBL carriage of these isolates at phenotypic and genotypic levels. Methods: One hundred and two clinical Escherichia coli isolates were recovered from UTI suspects and analyzed for ESBL production at phenotypic and genotypic levels using Modified Double Disc Synergy Test and Polymerase Chain Reaction respectively. Results: Of the 102 isolates, 100(98.04%) were associated with MDR phenotypes. The isolates showed variable resistance to all the antibiotics used in the study. The resistance rates were 99.0%, 97.1%, 88.2%, 82.4%, 81.4%, 65.7%, 54.9%, 46.1%, 46.1%, 23.5% for ampicillin, trimethoprim-sulfamethoxazole, ciprofloxacin, ceftriaxone, ceftazidime, amoxicillin-clavulanate, gentamycin, cefoxitin, nitrofurantoin and imipenem, and respectively. The prevalence of phenotypic ESBL production was 74.5%. Based on the PCR results, the randomly selected 20 ESBL-positive isolates possessed one or more ESBLs genes. CTX-M type was the predominant ESBLs type (100%), while those for TEM and SHV-types were 85% and 80% respectively. Four genotype patterns were detected (CTX-M, TEM+CTX-M, SHV+CTX-M and SHV+TEM+CTX-M). The genotype SHV+TEM+CTX-M, was the predominant (70%), followed by the genotype TEM +CTX-M combination (15%). The occurrences of the genotypes, CTX-M and SHV+CTX-M were 5% and 10% respectively. Conclusion: This study found a high rate of Phenotypic ESBL production (74.5%) among the isolates with multidrug resistance, CTX-M as the predominant ESBLs type (100%) and combination of SHV+TEM+CTX-M as the predominant genotype (70%).

Carriage Prevalence of Extended-Spectrum β-Lactamase Producing Enterobacterales in Outpatients Attending Community Health Centers in Blantyre, Malawi

Antimicrobial resistance due to extended-spectrum β-lactamase (ESBL) production by Enterobacterales is a global health problem contributing to increased morbidity and mortality, particularly in resource-constrained countries. We aimed to determine the prevalence of extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) in community patients in Blantyre, Malawi. Clinical samples were collected from 300 patients and screened for ESBL-E using a CHROMagarTM ESBL medium. Confirmation of ESBL production was done by a combination disk test (CDT). The prevalence of community-acquired ESBL-E was 16.67% (50/300, 95% CI = 12.43–20.91%). The most common ESBL-E species isolated was Escherichia coli (66%). All ESBL-E isolates were resistant to Trimethoprim-Sulfamethoxazole except for 2% of E. coli. Besides this, all ESBL-E were susceptible to Imipenem and only 4% were resistant to Meropenem. No patients with a positive ESBL-E phenotype had a history of hospital admission in the last three months, and the carriage of ESBL-E was neither associated with the demographic nor the clinical characteristics of participants. Our findings reveal a low presence of ESBL-E phenotypes in community patients. The low prevalence of ESBL-E in the community settings of Blantyre can be maintained if strong infection and antimicrobial use-control strategies are implemented.

Changes of antibiotic resistance over time among Escherichia coli peritonitis in Southern China

Escherichia coli ( E. coli) is the main cause of Gram-negative bacterial peritonitis among peritoneal dialysis patients. According to the 2016 update of the International Society for Peritoneal Dialysis Peritonitis Recommendations, drug susceptibilities of specific organisms should be regularly monitored. The aim of this study was to examine the evolution of antimicrobial resistance of E. coli peritonitis from 2006 to 2018. Two hundred and fifty-three episodes of E. coli peritonitis were enrolled in our study, corresponding to a rate of 0.024 episodes per patient-year. According to drug sensitivity test results, isolates were most sensitive to carbapenems, followed by cefmetazole, piperacillin/tazobactam, cefotetan and amikacin, with an overall rate of more than 90% in both cohorts. Cefazolin and ciprofloxacin resistance increased significantly from 2006–2011 to 2012–2018. Conversely, cefepime and ceftazidime resistance decreased significantly. The extended-spectrum β-lactamase (ESBL) rate fluctuated from 34.7% in 2006–2011 to 46.8% in 2012–2018. Compared with the ESBL-negative strains, ESBL-producing E. coli were more likely be resistant to ampicillin, ampicillin/sulbactam, cephalosporins, quinolones, aminoglycosides, furadantin and sulfamethoxazole and accounted for over 50% of the drug resistance. In the correlation analysis, E. coli displayed significantly increased resistance to cefazolin and ciprofloxacin, a finding correlated with ESBL production ( r = 0.883 and 0.276 respectively, p < 0.001 and p = 0.003). In conclusion, the rate of E. coli peritonitis declined stably in recent years, but the resistance to antimicrobial was high.

Molecular Epidemiology of blaCMY-1, blaCMY-2, blaFOX Genes in K. pneumoniae From Elderly Patients in Tehran, Iran

The growth rate of the population aging is increasing worldwide. To assess antimicrobial susceptibility of extended-spectrum β-lactamase- (ESBL-) producing Klebsiella pneumoniae Isolated from Patients aging in Rasool Akram, Hospital, as well as to identify AmpC genes. 100 K. pneumoniae strain isolated from different clinical samples. Isolates resistant to oxyimino-cephalosporins and to cefoxitin evaluated to phenotypic ESBL production and to phenotypic AmpC production, respectively. Detection of resistance genes was then performed using primers specific for AmpC genes. Piperacillin/tazobactam and carbapenems remained the active β-lactam antibiotic against K. pneumoniae. ESBLs were detected among 40 (40%) of K. pneumoniae isolates. CMY-1 gene was detected in 34.3% of all AmpC-positive isolates, whereas CMY-2 and FOX genes were 14.2% and 28.6%, respectively. The consumption of Carbapenem family drugs is high in Iranian hospitals which are used as a first line of treatment without antibiotic susceptibility testing. Therefore, increase in antibiotic resistance to this family drugs is unavoidable in the near future. Therefore, it is necessary to take the necessary measures to modify the administration and use of antibiotics.

EXTENDED SPECTRUM BETA LACTAMASE PRODUCING UROPATHOGENS IN A TERTIARY CARE HOSPITAL IN SOUTH INDIA: A CLINICO MICROBIOLOGICAL STUDY

Introduction: Urinary Tract Infection (UTI) is the most common bacterial infection encountered in both hospital and community setup and the presence of drug resistance carries remarkable clinical implication. Drug resistant phenotypes like ESBL (Extended Spectrum Beta lactamase producers) are difcult to treat causing increased morbidity. Aims: The present study aims to determine the prevalence of ESBL producing Enterobacteriacea among Uropathogens and to determine the Antibiotic susceptibility pattern. Materials and Methods :A total of 726 urine samples were obtained and processed as per standard microbiological techniques .Antibiotic susceptibility testing was done by Kirby Bauer disc diffusion method. All the isolates were screened for ESBL production and conrmed by Double Disc Synergy test (DDST).Differences between the antibiotic susceptibility pattern ,Various risk factors were assessed among the ESBL producing and non ESBLproducing bacteria and the signicance was analyzed . Statistical analysis used:Chi square test.(p < 0.05 signicant) Results: A total of 726 urine samples were processed of which 421 bacteria belonging to Enterobacteriaceae were included in the study. Most common organism isolated was Escherichia coli 279 (66.27%).Highest susceptibility was observed for Imipenem 361 (85.7%) and Amikacin 356 (84.5%).Out of 461 isolates, 235 (55.8%) isolates were positive for ESBL screening all the isolates were conrmed with DDST. There was a signicant difference for Diabetes mellitus, CAUTI and Inpatients among the antibiotic susceptibility pattern between ESBL and non ESBL producers.(p<0.0001) Conclusions: Early detection of Multidrug resistance isolates like ESBLproducers in routine testing could help avoid treatment failure. Screening for ESBL production needs to be carried out regularly in every clinical diagnostic laboratory to guide clinicians in proper selection of antibiotics. Continued monitoring of the susceptibility pattern of ESBLproducing bacteria will provide valuable information regarding the local antimicrobial susceptibility pattern which in turn will guide in choosing the initial empirical therapy