Real-time PCR for detection of the O25b-ST131 clone of Escherichia coli and its CTX-M-15-like extended-spectrum β-lactamases

Shiga toxin-producing Escherichia coli (STEC) are associated with acute gastroenteritis worldwide, which induces a high economic burden on both healthcare and individuals. Culture-independent diagnostic tests (CIDT) in frontline microbiology laboratories have been implemented in Alberta since 2019. The objectives of this study were to determine the association between gene detection and culture positivity over time using STEC microbiological clearance samples and also to establish the frequency of specimen submission. Both stx genes’ amplification by real-time PCR was performed with DNA extracted from stool samples using the easyMAG system. Stools were inoculated onto chromogenic agar for culture. An association between gene detection and culture positivity was found to be independent of which stx gene was present. CIDT can provide rapid reporting with less hands-on time and technical expertise. However, culture is still important for surveillance and early cluster detection. In addition, stool submissions could be reduced from daily to every 3–5 days until a sample is negative by culture.

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Real-Time PCR Determination of Escherichia coli Genomic DNA Contamination in Plasmid Preparations

Analytical Biochemistry ◽

10.1006/abio.2001.5480 ◽

2002 ◽

Vol 301 (1) ◽

pp. 151-153 ◽

Cited By ~ 10

Author(s):

Adrián Vilalta ◽

Vanessa Whitlow ◽

Terrie Martin

Keyword(s):

Escherichia Coli ◽

Real Time ◽

Real Time Pcr ◽

Genomic Dna ◽

Dna Contamination

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Optimization of a 3′-minor groove binder-DNA probe targeting the uidA gene for rapid identification of Escherichia coli O157:H7 using real-time PCR

Molecular and Cellular Probes ◽

10.1016/j.mcp.2003.07.001 ◽

2003 ◽

Vol 17 (6) ◽

pp. 275-280 ◽

Cited By ~ 27

Author(s):

Ken J Yoshitomi ◽

Karen C Jinneman ◽

Stephen D Weagant

Keyword(s):

Escherichia Coli ◽

Real Time ◽

Real Time Pcr ◽

Minor Groove ◽

Rapid Identification ◽

Dna Probe ◽

Escherichia Coli O157 ◽

Uida Gene ◽

Minor Groove Binder

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Real-time PCR for differentiation of F18 variants among enterotoxigenic and Shiga toxin-producing Escherichia coli from piglets with diarrhoea and oedema disease

The Veterinary Journal ◽

10.1016/j.tvjl.2013.07.021 ◽

2013 ◽

Vol 198 (2) ◽

pp. 538-540 ◽

Cited By ~ 8

Author(s):

Jae-Won Byun ◽

Byeong Yeal Jung ◽

Ha-Young Kim ◽

John M. Fairbrother ◽

Myoung-Heon Lee ◽

...

Keyword(s):

Escherichia Coli ◽

Real Time ◽

Shiga Toxin ◽

Real Time Pcr ◽

Oedema Disease

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Application of quantitative real-time PCR compared to filtration methods for the enumeration of Escherichia coli in surface waters within Vietnam

Journal of Water and Health ◽

10.2166/wh.2016.173 ◽

2016 ◽

Vol 15 (1) ◽

pp. 155-162 ◽

Cited By ~ 5

Author(s):

Pierangeli G. Vital ◽

Nguyen Thi Van Ha ◽

Le Thi Hong Tuyet ◽

Kenneth W. Widmer

Keyword(s):

Escherichia Coli ◽

Real Time ◽

Surface Waters ◽

Real Time Pcr ◽

Membrane Filtration ◽

Quantitative Real Time Pcr ◽

Wet Season ◽

Culture Methods ◽

Fecal Indicator ◽

Filtration Method

Surface water samples in Vietnam were collected from the Saigon River, rural and suburban canals, and urban runoff canals in Ho Chi Minh City, Vietnam, and were processed to enumerate Escherichia coli. Quantification was done through membrane filtration and quantitative real-time polymerase chain reaction (PCR). Mean log colony-forming unit (CFU)/100 ml E. coli counts in the dry season for river/suburban canals and urban canals were log 2.8 and 3.7, respectively, using a membrane filtration method, while using Taqman quantitative real-time PCR they were log 2.4 and 2.8 for river/suburban canals and urban canals, respectively. For the wet season, data determined by the membrane filtration method in river/suburban canals and urban canals samples had mean counts of log 3.7 and 4.1, respectively. While mean log CFU/100 ml counts in the wet season using quantitative PCR were log 3 and 2, respectively. Additionally, the urban canal samples were significantly lower than those determined by conventional culture methods for the wet season. These results show that while quantitative real-time PCR can be used to determine levels of fecal indicator bacteria in surface waters, there are some limitations to its application and it may be impacted by sources of runoff based on surveyed samples.

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Investigation of High-Risk ST131 Clone in Extended Spectrum β-Lactamase–Producing Escherichia coli Isolates in Children

Journal of Pediatric Infectious Diseases ◽

10.1055/s-0041-1730995 ◽

2021 ◽

Author(s):

Mehmet E. Bulut ◽

Gülen Hürkal ◽

Nazan Dalgıç

Keyword(s):

Escherichia Coli ◽

High Risk ◽

Pediatric Patients ◽

Pediatric Population ◽

Maldi Tof Ms ◽

E Coli ◽

Maldi Tof ◽

Extended Spectrum ◽

St131 Clone ◽

Tof Ms

Abstract Objective Antimicrobial resistance poses a serious threat to children's health. In recent years, high-risk Escherichia coli ST131 has become an important target for global surveillance studies. The E.coli ST131 clone is associated with extended spectrum β-lactamase (ESBL) production, as well as multidrug resistance and treatment failure. Studies on this clone in the pediatric age group are limited. We aim to investigate the rate of high-risk E. coli ST131 clone in ESBL-positive E. coli isolates obtained from pediatric patients. Methods A total of 292 ESBL-positive E. coli isolates from clinical samples of pediatric patients was included in the study. MALDI-TOF MS system was used for bacterial identification. Susceptibility tests were performed using BD Phoenix automated system. ST131 detection was done by MALDI-TOF-MS. Fisher's exact test was used to compare the groups (significance <0.05). Results A total of 292 isolates was analyzed. The high-risk ST131 clone was detected in 117 (40%) of the 292 ESBL-positive isolates. ST131 rates were found to be significantly higher in children under the age of 5 years compared with children over the age of 5 years (49.3 vs. 31.1%, p = 0.0019). Ciprofloxacin resistance was higher in ST131 isolates (45.6 vs. 31.7%; p < 0.05). Conclusion The rate of the ST131 clone was found to be high in the pediatric population. The significantly high rate of resistance to ciprofloxacin, which is not commonly used in the pediatric population, in ST131 isolates reveals the importance of the spread of high-risk clones for the development of resistance.

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