Prevalance of Extended Spectrum Beta Lactamases (ESBL) Producing Escherichia Coli Isolated From Clinical Samples at Tertiary Care Hospital Peshawar

Escherichia coli is Gram negative, facultative and non sporulating rod shaped bacteria. It is commonly inhabitant of the gastrointestinal tract of humans and animals. E. coli cause diseases like urinary tract infection cholecystitis, cholangitis and traveler’s diarrhoea and the UTI which is more prevalent worldwide. E. coli cause complication like Hemolytic Uremic Syndrome which leads to renal failure, Thrombotic Thrombocytopenic Purpura, septicemia and peritonitis. Extend spectrum beta lactamase enzyme produce by E. coli which capable of hydrolyzing first and third generation cephalosporin, and is inhibited by beta lactamase inhibitor. A total of 150 clinical samples (blood, urine, wound swab, body fluids) were collected from Post Graduate Lady Reading Hospital Peshawar. Different media used were Nutrient agar, MacConky agar and Cysteine, Lactose and Electrolyte-Deficient agar. E. coligive pink colonies on MacConky agar because it is lactose fermenter. For further confirmation different biochemical tests were performed like triple sugar iron, Indole, and citrate utilization tests. The antibiotics susceptibility and resistivity was checked by disk diffusion method and different antibiotics were used. For ESBL detection combined disk method was performed. In the clinical samples the percentage of Gram positive bacteria in blood was (20%), urine (14.2%), wound swab (83.3%), and body fluids (8%), and the Gram negative in urine was (80%), blood (7%), wound swab (10%), and body fluids (0%). E. coli was more prevalent in urine which was 25(35.71%) and ESBL producing E. coli was 5(20%). The ESBL producing E. coli was resistant to ciprofloxacin (100%), amikacin (40%), amoxicillin+clavulanic acid (40%), levofloxacin (80%), tazobactum+pipracilline (20%), gentamycin (100%), trimethoprim (60%), cefotaxime (100%) and meropenem (0%). Sensitivity toward levofloxacin (20%), tazobactum+pipracilline (80%), gentamycin (0%), trimethoprim (40%), cefotaxime (0%) and meropenem (100%), ciprofloxacin (0%), amikacin (60%), amoxicillin+clavulanic acid (60%). The most effective antibiotic against ESBL producing E. coli was Meropenem while least effective antibiotics against ESBL producing E. coli were Gentamycin and Ciprofloxacin.

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Beta-Lactamase-Producing Escherichia coli Isolates Recovered from Pig Handlers in Retail Shops and Abattoirs in Selected Localities in Southern Nigeria: Implications for Public Health

Antibiotics ◽

10.3390/antibiotics10010009 ◽

2020 ◽

Vol 10 (1) ◽

pp. 9

Author(s):

Olivia Sochi Egbule ◽

Benson C. Iweriebor ◽

Edward Ikenna Odum

Keyword(s):

Escherichia Coli ◽

Clavulanic Acid ◽

Multidrug Resistant ◽

Beta Lactamase ◽

Extended Spectrum Beta Lactamase ◽

E Coli ◽

Resistance Evolution ◽

Resistance Patterns ◽

Amoxicillin Clavulanic Acid ◽

And Gender

Antibiotic resistance evolution among pathogenic microorganisms has become a huge burden globally as it has increased the burden of diseases amongst humans and animals. The prevalence of extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-Ec) and metallo beta-lactamase-producing Escherichia coli (MBL-Ec) isolated from pig abattoir and handlers in retail shops was studied. In addition, the relationship between the isolates’ prevalence and the background characteristics of the butchers/retailers was also investigated. Samples from 32 hand swabs of pork sellers at retail shops and 8 butchers at abattoirs, as well as 272 swabs taken from knives, tables, floors, water troughs, and carcasses from both retail shops and abattoirs, were collected. Escherichia coli (E. coli) was isolated from hand swabs, fomites, and carcasses and were identified by standard microbiological procedures. The isolates susceptibility to nitrofurantoin (300 µg), ciprofloxacin (5 µg), ceftazidime (30 µg), cefuroxime (30 µg), gentamicin (10 µg), cefixime (5 µg), ofloxacin (5 µg), amoxicillin/clavulanic acid (30 µg), imipenem (10 µg), and meropenem (10 µg) and their ability to produce ESBL and MBL was determined by phenotypic methods. Demographic information of the handlers was retrieved by means of a structured questionnaire and, in some cases, via face to face interviews. Out of 104 E. coli isolates from both sources, 52 (50.0%) and 8 (7.7%) were ESBL and MBL producers, respectively. ESBL was more prevalent on the hands of the retailers (40.6%) and butchers (75.0%). The isolates were 100% resistant to ceftazidime, cefotaxime, and amoxicillin–clavulanic acid and 4.8% resistant to nitrofurantoin. Diverse resistance patterns were observed among ESBL-Ec and MBL-Ec. It was found that 90% of ESBL-Ec and 100% of MBL-Ec were multidrug-resistant. A possible epidemiological link between the two sources was observed. The prevalence of E. coli ESBL- and MBL-producing isolates was associated with the duty performed by handlers (p = 0.012) and gender (p = 0.012). Our results provide evidence that the handlers’ hands and abattoir environment had a great role to play in the high prevalence and resistance profiles of the microorganisms.

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Antibiotic resistance and detection of plasmid mediated colistin resistance mcr-1 gene among Escherichia coli and Klebsiella pneumoniae isolated from clinical samples

Gut Pathogens ◽

10.1186/s13099-021-00441-5 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Deepa Karki ◽

Binod Dhungel ◽

Srijana Bhandari ◽

Anil Kunwar ◽

Prabhu Raj Joshi ◽

...

Keyword(s):

Escherichia Coli ◽

Drug Resistance ◽

Klebsiella Pneumoniae ◽

Clinical Samples ◽

Gram Negative Bacteria ◽

Beta Lactamase ◽

Drug Resistant ◽

Colistin Resistance ◽

Gram Negative ◽

E Coli

Abstract Background The prevalence of antimicrobial resistance (AMR) among Gram-negative bacteria is alarmingly high. Reintroduction of colistin as last resort treatment in the infections caused by drug-resistant Gram-negative bacteria has led to the emergence and spread of colistin resistance. This study was designed to determine the prevalence of drug-resistance among beta-lactamase-producing strains of Escherichia coli and Klebsiella pneumoniae, isolated from the clinical specimens received at a tertiary care centre of Kathmandu, Nepal during the period of March to August, 2019. Methods A total of 3216 different clinical samples were processed in the Microbiology laboratory of Kathmandu Model Hospital. Gram-negative isolates (E. coli and K. pneumoniae) were processed for antimicrobial susceptibility test (AST) by using modified Kirby-Bauer disc diffusion method. Drug-resistant isolates were further screened for extended-spectrum beta-lactamase (ESBL), metallo-beta-lactamase (MBL), carbapenemase and K. pneumoniae carbapenemase (KPC) production tests. All the suspected enzyme producers were processed for phenotypic confirmatory tests. Colistin resistance was determined by minimum inhibitory concentration (MIC) using agar dilution method. Colistin resistant strains were further screened for plasmid-mediated mcr-1 gene using conventional polymerase chain reaction (PCR). Results Among the total samples processed, 16.4% (529/3216) samples had bacterial growth. A total of 583 bacterial isolates were recovered from 529 clinical samples. Among the total isolates, 78.0% (455/583) isolates were Gram-negative bacteria. The most predominant isolate among Gram-negatives was E. coli (66.4%; 302/455) and K. pneumoniae isolates were 9% (41/455). In AST, colistin, polymyxin B and tigecycline were the most effective antibiotics. The overall prevalence of multidrug-resistance (MDR) among both of the isolates was 58.0% (199/343). In the ESBL testing, 41.1% (n = 141) isolates were confirmed as ESBL-producers. The prevalence of ESBL-producing E. coli was 43% (130/302) whereas that of K. pneumoniae was 26.8% (11/41). Similarly, 12.5% (43/343) of the total isolates, 10.9% (33/302) of E. coli and 24.3% of (10/41) K. pneumoniae were resistant to carbapenem. Among 43 carbapenem resistant isolates, 30.2% (13/43) and 60.5% (26/43) were KPC and MBL-producers respectively. KPC-producers isolates of E. coli and K. pneumoniae were 33.3% (11/33) and 20% (2/10) respectively. Similarly, 63.6% (21/33) of the E. coli and 50% (5/10) of the K. pneumoniae were MBL-producers. In MIC assay, 2.2% (4/179) of E. coli and 10% (2/20) of K. pneumoniae isolates were confirmed as colistin resistant (MIC ≥ 4 µg/ml). Overall, the prevalence of colistin resistance was 3.1% (6/199) and acquisition of mcr-1 was 16.6% (3/18) among the E. coli isolates. Conclusion High prevalence of drug-resistance in our study is indicative of a deteriorating situation of AMR. Moreover, significant prevalence of resistant enzymes in our study reinforces their roles in the emergence of drug resistance. Resistance to last resort drug (colistin) and the isolation of mcr-1 indicate further urgency in infection management. Therefore, extensive surveillance, formulation and implementation of effective policies, augmentation of diagnostic facilities and incorporation of antibiotic stewardship programs can be some remedies to cope with this global crisis.

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Antimicrobial Susceptibility Patterns of Escherichia coli among Tunisian Outpatients with Community-Acquired Urinary Tract Infection (2012-2018)

Current Urology ◽

10.1159/000499238 ◽

2020 ◽

Vol 14 (4) ◽

pp. 200-205

Author(s):

Nawel Daoud ◽

Manel Hamdoun ◽

Hela Hannachi ◽

Chedlia Gharsallah ◽

Wiem Mallekh ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Tract Infection ◽

Urinary Tract ◽

Tract Infection ◽

Clavulanic Acid ◽

Antimicrobial Susceptibility ◽

Diffusion Method ◽

E Coli ◽

Amoxicillin Clavulanic Acid ◽

Susceptibility Patterns

Introduction: Community-acquired urinary tract infection is one of the most common reasons for consultation in everyday practice; it represents a major source of antibiotic consumption. Escherichia coli (E. coli) is the main pathogen incriminated. Objective:· The aim of this study was to evaluate antimicrobial susceptibility patterns of community-acquired uropathogenic E coli throughout a 7-year period. Methodology: All strains of E. coli isolated from urine samples between January 1st 2012 and December 31st 2018 were included. Presence of ≥ 103 CFU/ml in urine culture media was considered as significant for urinary tract infection. The identification of E. coli strains was realized using standard laboratory techniques. Antibiotic susceptibility testing was performed using the disk diffusion method according to the CA-SFM/ EUCAST criteria. Results: A total of 1,335 E. coli strains were isolated. Overall susceptibility rates to antimicrobial agents were as follows: ampicillin 39.1%, amoxicillin-clavulanic acid 64.9%, cefotaxime 94.9%, trimethoprim/sulfamethox-azole 67.6%, ciprofloxacin 89.2%, ofloxacin 86.9%, amikacin 98.6%, gentamicin 93.9%, nitrofurantoin 97.6% and fosfomycin 99.3%. All isolates were susceptible to carbapenems. The frequency of extended spectrum beta-lactamases-producing E. coli strains was 4.7%. Susceptibility rates of E. coli for ampicillin, trimethoprim/sulfamethoxazole and amikacin remained relatively stable over the study period, whereas susceptibility to amoxicillin-clavulanic acid, cefotaxime and fluoroquinolones showed a 2-phase pattern. As for gentamicin, a continuous decrease in susceptibility rates was observed. Conclusion: Antimicrobial susceptibility profiles of uropathogenic E. coli are constantly changing, due to modifications in the antibiogram interpretation criteria and antibiotic prescription habits. Rigorous surveillance of resistance rate is necessary to determine appropriate empirical treatment and limit the spread of multiresistant strains.

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Escherichia coli of Ready-to-Eat (RTE) Meats Origin Showed Resistance to Antibiotics Used by Farmers

Antibiotics ◽

10.3390/antibiotics9120869 ◽

2020 ◽

Vol 9 (12) ◽

pp. 869

Author(s):

Abdulai Abass ◽

Frederick Adzitey ◽

Nurul Huda

Keyword(s):

Escherichia Coli ◽

Clavulanic Acid ◽

Bacterial Infections ◽

Tertiary Education ◽

Antibiotic Usage ◽

Diffusion Method ◽

Resistance Pattern ◽

Disk Diffusion Method ◽

E Coli ◽

Amoxicillin Clavulanic Acid

Bacterial foodborne infections, including meat-derived infections, are globally associated with diseases and some deaths. Antibiotics are sometimes used to treat bacterial infections. The use of antibiotics by farmers contributes to the development of resistance by foodborne pathogens. This study aimed to investigate the antibiotics used by farmers and the occurrence of antibiotic-resistant Escherichia coli in ready-to-eat (RTE) meat sources. Data was obtained from livestock farmers through the administration of semistructured questionnaires (n = 376) to obtain information on their demographics, knowledge and antibiotic usage. The procedure in the USA Food and Drug Administration (FDA)’s Bacteriological Analytical Manual was used for E. coli detection. Antibiotic resistance test was performed using the disk diffusion method. The findings revealed that most of the farmers were male (74.5%), were aged 30−39 years (28.5%), had tertiary education (30.3%) and had 6−10 years of experience in livestock husbandry. Sheep (65.7%) were the most reared livestock, and antibiotics were mostly used to treat sick animals (36.7%). Tetracycline (27.7%) was the most common antibiotic used by farmers, followed by amoxicillin/clavulanic acid (18.6%) and trimethoprim/sulfamethoxazole (11.7%). Most farmers (56.1%) said they had knowledge of antibiotic usage. The prevalence of E. coli in RTE meats was lowest in pork (6.0%) and highest in chevon (20.0%). E. coli isolates from RTE meats were highly resistant to teicoplanin (96.77%), tetracycline (93.55%), amoxicillin/clavulanic (70.97%), azithromycin (70.97%) and trimethoprim/sulfamethoxazole (58.06%) but was susceptible to chloramphenicol (93.55%), ciprofloxacin (61.29%) and ceftriaxone (58.06%). The multiple antibiotic index ranged from 0.22 to 0.78. Multidrug resistance (93.55%) was high among the E. coli isolates. The resistance pattern AmcAzmTecTeSxt (amoxicillin/clavulanic acid–azithromycin–telcoplanin–tetracycline–trimethoprim/sulfamethoxazole) was the most common. The use of antibiotics by farmers must be well regulated. Sellers of RTE meats also ought to take hygiene practices seriously to keep meat safe and healthy for public consumption.

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ANALYSIS OF THE ANTIBIOGRAM PROFILES OF BIOFILM FORMING STAPHYLOCOCCUS AUREUS AND ESCHERICHIA COLI

Universal Journal of Pharmaceutical Research ◽

10.22270/ujpr.v6i6.695 ◽

2022 ◽

Author(s):

Amal Ali Bahakim ◽

Eidha Ali Bin-Hameed

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Peer Review ◽

Clavulanic Acid ◽

Bacterial Biofilm ◽

Clinical Samples ◽

Antibiotics Resistance ◽

P Value ◽

E Coli ◽

Amoxicillin Clavulanic Acid

Background and Objectives: Bacteria that attach to the surfaces and produce polymeric matrix resulting in the biofilms formation are involved in a wider range of human infections. Biofilms forming Staphylococcus aureus and Escherichia coli are considered to be highly antibiotics resistant. This study aimed to analysis the antibiogram profile of biofilm forming S. aureus and E. coli in Mukalla city, Hadhramaut,Yemen. Methods: Sixty clinical isolates of S. aureus and E. coli were isolated from different clinical samples, and identified by standard bacteriological methods, then subjected to biofilm formation detection by tissue culture plate (TCP) method. The antibiotics susceptibility test was performed by disc diffusion (Kirby-Bauer) method. Chi-square test was used to analyze the data and p value< 0.05 was taken as significant. Results: Among the total isolates S. aureus and E. coli, TCP method detected 55% of isolates as strong, 25% as moderate and 25% as weak/non-biofilm producers. Biofilm forming of S. aureus developed significantly higher degrees of antibiotic resistance of amoxicillin/clavulanic acid100%, ceftazidime 95.8%, cefotaxime62.5%, cefadroxil 45.8%, ciprofloxacin 41.7% and ceftriaxone 25% with significant statistics correlation the resistance of amoxicillin/clavulanic acid and ceftazidime and bacterial biofilm production (p-value< 0.05). The rates of antibiotics resistance biofilm E. coli were 100%, 91.7%, 75%, 70.8%, 66.7%, 62.5% and 33.3%for amoxicillin/clavulanic acid, cefadroxil, cefotaxime, ceftazidime, ceftriaxone, ciprofloxacin and co-trimoxazole respectively with statistically significant correlation of cefadroxil resistance (p-value < 0.05). Conclusion: TCP method showed that S. aureus and E. coli isolates have high degree of biofilm forming ability. A high antibiotics resistance found in biofilm producers isolates than non-biofilm producers. Peer Review History: Received: 23 October 2021; Revised: 1 December; Accepted: 17 December, Available online: 15 January 2022 Academic Editor: Dr. Nuray Arı, Ankara University, Turkiye, [email protected] UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file: Reviewer's Comments: Average Peer review marks at initial stage: 5.0/10 Average Peer review marks at publication stage: 7.0/10 Reviewers: Dr. Wadhah Hassan Ali Edrees, Hajja University, Yemen, [email protected] Dr. Tamer Elhabibi, Suez Canal University, Egypt, [email protected] Dr. Rawaa Souhil Al-Kayali, Aleppo University, Syria, [email protected] Rola Jadallah, Arab American University, Palestine, [email protected] Similar Articles: PREVALENCE OF STAPHYLOCOCCUS AUREUS IN DENTAL INFECTIONS AND THE OCCURRENCE OF MRSA IN ISOLATES PREVALENCE OF METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS (MRSA) AND ANTIMICROBIAL SUSCEPTIBILITY PATTERNS AT A PRIVATE HOSPITAL IN SANA'A, YEMEN

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Antimicrobial Susceptibility Pattern of Staphylococcus Species from Clinical Samples

Journal of Internal Medicine and Emergency Research ◽

10.37191/mapsci-2582-7367-1(1)-005 ◽

2020 ◽

Author(s):

Muhammad Ali

Keyword(s):

Clavulanic Acid ◽

Antibiotic Susceptibility ◽

Vaginal Swab ◽

Diffusion Method ◽

Clinical Samples ◽

Susceptibility Pattern ◽

Mannitol Salt Agar ◽

Agar Disc ◽

Microbiological Methods ◽

Amoxicillin Clavulanic Acid

The research was aimed to evaluate the antibiotic susceptibility pattern of Staphylococcus species from clinical samples obtained from some hospitals in Kano metropolis, Nigeria. The ear swab, high vaginal swab (HVS), wound swab and urine samples from the patients attending the hospitals were collected and inoculated onto the surface of freshly prepared Nutrient agar for bacterial isolation. The bacteria isolated were identified by conventional microbiological methods namely; Gram staining, biochemical test (such as catalase, coagulase, and DNase test), mannitol salt agar and heamolysis test. The isolates were subjected to antibiotic susceptibility testing using the agar disc diffusion method. The result showed that S. aureus was highly susceptible to Ciprofloxacin 105 (68.63%), Gentamicin 102 (66.67%), Levofloxacin 95 (62.08%) and Amikacin 90 (58.82%), S. epidermidis was highly susceptible to Gentamicin 13 (61.90%), Levofloxacin 12 (57.14%) and Nitrofurantoin 11 (52.38%) while S. saprophyticus was highly susceptible to Cefoxitin 7 (77.78%), Gentamicin 6 (66.67%) and Nitrofurantoin 5 (55.56%). On the other hand, S. aureus was highly resistant to Cefuroxime 153 (100%), Ceftazidime 150 (98.04%), Amoxicillin/clavulanic acid 120 (78.43%) and Cloxacillin 111 (72.55%), S. epidermidis was highly resistant to Ceftazidime 20 (95.24%), Cloxacillin 19 (90.48%) then Cefoxitin, Erythromycin and Amoxicillin/clavulanic acid with 15 (71.43%) both. S. saprophyticus was highly resistant to Cefepime 9 (100%), Cloxacillin 8 (88.89%), Ceftazidime 7 (77.78%), Imipenem and Erythromycin with 6 (66.67%) respectively. There is a statistical difference in the sensitivity of the isolates against the antibiotics used at p<0.05. It is concluded that Staphylococcus species develop resistance to some classes of antibiotics.

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Evaluation of extended spectrum beta lactamase enzymes prevalence in clinical isolates of Escherichia coli

Microbiology Research ◽

10.4081/mr.2011.e8 ◽

2011 ◽

Vol 2 (1) ◽

pp. 8

Author(s):

Ronak Bakhtiari ◽

Jalil Fallah Mehrabadi ◽

Hedroosha Molla Agamirzaei ◽

Ailar Sabbaghi ◽

Mohammad Mehdi Soltan Dallal

Keyword(s):

Escherichia Coli ◽

Disk Diffusion ◽

Confirmatory Test ◽

Diffusion Method ◽

Multi Drug Resistance ◽

Beta Lactamase ◽

Disk Diffusion Method ◽

Extended Spectrum Beta Lactamase ◽

E Coli ◽

Extended Spectrum

Resistance to b-lactam antibiotics by gramnegative bacteria, especially Escherichia coli (E. coli), is a major public health issue worldwide. The predominant resistance mechanism in gram negative bacteria particularly E. coli is via the production of extended spectrum beta lactamase (ESBLs) enzymes. In recent years, the prevalence of b-lactamase producing organisms is increased and identification of these isolates by using disk diffusion method and no-one else is not satisfactory. So, this investigation focused on evaluating the prevalence of ESBL enzymes by disk diffusion method and confirmatory test (Combined Disk). Five hundred clinical samples were collected and 200 E. coli isolates were detected by standard biochemical tests. To performing initial screening of ESBLs was used from Disk diffusion method on E. coli isolates. A confirmation test (Combined Disk method) was performed on isolates of resistant to cephalosporin's indicators. Up to 70% isolates exhibited the Multi Drug Resistance phenotype. In Disk diffusion method, 128(64%) E. coli isolates which resistant to ceftazidime and cefotaxime while in Combined Disk, among 128 screened isolates, 115 (89.8%) isolates were detected as ESBLs producers. This survey indicate beta lactamase enzymes are playing a significant role in antibiotic resistance and correct detection of them in phenotypic test by using disk diffusion and combined Disk is essential for accurate recognition of ESBLs.

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PREVALENCE OF CEPHALOSPORIN-RESISTANT GRAM-NEGATIVE BACILLI FROM CLINICAL SAMPLES

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2016.v9s2.13456 ◽

2016 ◽

pp. 176

Author(s):

Kavi Aniis ◽

Rajamanikandan Kcp ◽

Arvind Prasanth D

Keyword(s):

Clinical Samples ◽

Beta Lactamase ◽

Bacterial Isolates ◽

Beta Lactam ◽

Gram Negative ◽

Beta Lactamases ◽

Extended Spectrum Beta Lactamase ◽

E Coli ◽

Lactam Ring ◽

Esbl Producers

ABSTRACT Objective: Beta-lactams are the group of antibiotics that contain a ring called as “beta-lactam ring,” which is responsible for the antibacterial activity. The presence of resistance among Gram-negative organisms is due to the production of beta-lactamases enzymes that hydrolysis the beta-lactam ring thereby conferring resistance to the organism. This study is undertaken to determine the prevalence of extended-spectrum beta-lactamase (ESBL) producing Gram-negative organism from clinical samples. Methods: A total of 112 clinical samples were taken for this study. The combined disc synergistic test (CDST) was used for the phenotypic detection of ESBL producers from the clinical samples. The genotypic identification of ESBL producers was carried out by alkaline lysis method by isolation of plasmid DNA. Result: A total of 87 bacterial isolates were isolated and identified. Among them, Klebsiella (41%) was the predominant organism followed by Escherichia coli (33%), Proteus (10%), Pseudomonas (10%), and Serratia (6%). Among the various bacterial isolates, Klebsiella showed a higher percentage of resistance. The CDST showed that 8 isolates of Klebsiella, 3 isolates of E. coli, and 1 isolate of Pseudomonas were found to be ESBL producers. The genotypic confirmation showed that the two bacterial isolates, namely, Klebsiella and E. coli were found to possess temoniera (TEM) gene which was the 400-500 bp conferring resistance to the antibiotics. Conclusion: The results of this study suggest that early detection of ESBL producing Gram-negative organism is a very important step in planning the therapy of patient in Hospitals. CDST continues to be a good indicator in the detection of ESBL producers. Keywords: Beta-lactamases, Gram-negative bacilli, Extended-spectrum beta-lactamase, Resistance, Combined disc synergistic test.

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Escherichia coli ATCC 35218 as a Quality Control Isolate for Susceptibility Testing of Haemophilus influenzae with Haemophilus Test Medium

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.43.2.283 ◽

1999 ◽

Vol 43 (2) ◽

pp. 283-286 ◽

Cited By ~ 5

Author(s):

D. L. Butler ◽

C. J. Jakielaszek ◽

L. A. Miller ◽

J. A. Poupard

Keyword(s):

Escherichia Coli ◽

Quality Control ◽

Clavulanic Acid ◽

Susceptibility Testing ◽

Test Medium ◽

E Coli ◽

Mueller Hinton ◽

Quality Control Testing ◽

Amoxicillin Clavulanic Acid ◽

Lactamase Inhibitor

ABSTRACT Current National Committee for Clinical Laboratory Standards (NCCLS) susceptibility guidelines for quality control testing withHaemophilus influenzae do not include a β-lactamase-producing strain that could detect the deterioration of the β-lactamase inhibitor components of amoxicillin-clavulanic acid, ampicillin-sulbactam, and piperacillin-tazobactam. The objective of the study was to determine if comparable quality control results forEscherichia coli ATCC 35218, a β-lactamase-producing strain, would be produced for the three β-lactam–β-lactamase inhibitor agents with Haemophilus test medium and Mueller-Hinton medium. The criteria used in this study to determine if Haemophilus test medium was acceptable for quality control testing of E. coli ATCC 35218 was that 100% of the results obtained with an antimicrobial agent-methodology combination needed to be within the acceptable NCCLS ranges established with Mueller-Hinton medium. The MIC testing results obtained by the broth microdilution and E-test methods with amoxicillin-clavulanic acid and piperacillin-tazobactam were all within the NCCLS ranges; however, the results obtained with ampicillin-sulbactam by both methods were not within the NCCLS ranges. Acceptable results were obtained by the disk diffusion methodology with ampicillin-sulbactam and piperacillin-tazobactam but not with amoxicillin-clavulanic acid. When performing susceptibility testing with H. influenzae with the β-lactam–β-lactamase inhibitors, in addition to quality control testing with H. influenzae ATCC 49247, testing of E. coli ATCC 35218 on Haemophilus test medium is an effective way to monitor the β-lactamase inhibitors in some antimicrobial agent-methodology combinations.

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Properties of IRT-14 (TEM-45), a newly characterized mutant of TEM-type beta-lactamases.

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.41.2.374 ◽

1997 ◽

Vol 41 (2) ◽

pp. 374-378 ◽

Cited By ~ 29

Author(s):

M M Caniça ◽

M Barthélémy ◽

L Gilly ◽

R Labia ◽

R Krishnamoorthy ◽

...

Keyword(s):

Escherichia Coli ◽

Kinetic Parameters ◽

Clavulanic Acid ◽

Broad Spectrum ◽

Promoter Region ◽

Beta Lactamase ◽

Beta Lactamases ◽

Structural Modifications ◽

E Coli

IRT-14 (TEM-45) is a new mutant TEM-type beta-lactamase that was isolated from clinical Escherichia coli P37 and that confers resistance to broad-spectrum penicillins with reduced sensitivity to beta-lactamase inhibitors. The MICs of amoxicillin alone and of amoxicillin combined with 2 micrograms of clavulanic acid or 2 micrograms of tazobactam per ml were 4,096, 2,048, and 1,024 micrograms/ml, respectively. The strain was susceptible to cephalosporins, aztreonam, moxalactam, and imipenem. The enzyme was purified to homogeneity, and values of the kinetic parameters Kcat, Km, and Kcat/Km were determined for different substrates. This enzyme, with a pI of 5.2, was found to have reduced affinity for broad-spectrum penicillins and cephalosporins. The values of 50% inhibitory concentrations of clavulanic acid, sulbactam, tazobactam, and brobactam are correlated with the higher KmS for substrates. The resistance of E. coli P37 to mechanism-based inactivators results from a higher level of production of the TEM-derived enzyme due to the G-to-T substitution at position 162 (G-162-->T) in the promoter region of blaTEM and from the structural modifications resulting from the Met-69-->Leu and Arg-275-->Gln substitutions that characterize IRT-14 beta-lactamase.

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