A commentary on the role of molecular technology and automation in clinical diagnostics

O’Connor, Ciara; Fitzgibbon, Marie; Powell, James; Barron, Denís; O’Mahony, Jim; Power, Lorraine; O’Connell, Nuala H.; Dunne, Colum P.

doi:10.4161/bioe.28599

Cited by 18 publications

(13 citation statements)

References 32 publications

(31 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…MALDI-TOF MS (Bruker Diagnostics) identification was performed on all colonies, as previously described 22 . Antimicrobial susceptibility testing was performed using broth microdilution (ARIS Sensititre ® system-Thermo Fisher Scientific Inc, Masachusettts, USA).…”

Section: Microbiological and Molecular Detection Of Ndm-1mentioning

confidence: 99%

An Irish outbreak of New Delhi metallo-β-lactamase (NDM)-1 carbapenemase-producing Enterobacteriaceae: increasing but unrecognized prevalence

O’Connor

Cormican

Boo

et al. 2016

Journal of Hospital Infection

View full text Add to dashboard Cite

BackgroundCarbapenemase-producing Enterobacteriaceae (CPE) can cause healthcare-associated infections with high mortality rates. New Delhi metallo-beta-lactamase-1 (NDM-1) is amongst the most recently discovered carbapenemases. AimTo report the first outbreak of NDM-1 CPE in Ireland, including microbiological and epidemiological characteristics, and assessing the impact of infection prevention and control measures. MethodsRetrospective microbiological and epidemiological review. Cases were defined as patients with a CPE positive culture. Contacts were designated as roommates or ward mates. FindingsThis outbreak involved ten patients, with a median age of 71 years (range 45-90 years), located in three separate but affiliated healthcare facilities. One patient was infected (the index case); the nine others were colonised. Nine NDM-1-producing Klebsiella pneumoniae, a NDM-1-producing Escherichia coli and a K. pneumoniae carbapenemase (KPC)-producing Enterobacter cloacae were detected between week 24 2014 and week 37 2014. Pulsed field gel electrophoresis demonstrated similarity. NDM-1 positive isolates were meropenem resistant with MICs ranging from 12 to 32 µg/ml. All were tigecycline susceptible (MICs ≤1 µg/ml). One isolate was colistin resistant (MIC 4.0 µg/ml; mcr-1 gene not detected). In 2015, four further NDM-1 isolates were detected. Conclusions 3The successful management of this outbreak was achieved via the prompt implementation of enhanced infection prevention and control practices to prevent transmission. These patients did not have a history of travel outside of Ireland, but a number had frequent hospitalisations in Ireland, raising concerns regarding the possibility of increasing but unrecognised prevalence of NDM-1 and potential decline in value of travel history a marker of colonisation risk. KeywordsCarbapenemase-producing Enterobacteriaceae, New Delhi metallo-beta-lactamase-1 (NDM-1), multi-drug resistant organism, outbreak, Ireland. Study definitionsCases were defined as patients with a NDM-1 positive culture from any site during their hospitalisation. Contacts were designated as roommates or ward mates. Microbiological and molecular detection of NDM-1Since 2011, CPE surveillance at UHL had been performed on stool samples or rectal swabs using KPC-producer selective chromogenic agar (CHROMagar™ KPC, Paris, France).MALDI-TOF MS (Bruker Diagnostics) identification was performed on all colonies, as previously described 22 . Antimicrobial susceptibility testing was performed using broth microdilution (ARIS Sensititre ® system-Thermo Fisher Scientific Inc, Masachusettts, USA).Elevated carbapenem minimum inhibitory concentrations (MICs) for meropenem and ertapenem were confirmed by E-test (AB Biodisk, Solna, Sweden) following the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines; ertapenem resistance MIC >1 g/l, meropenem resistance MIC >8 g/l. Isolates with elevated carbapenem MICs were further evaluated using the modified Hodge test (MHT). Commercially available 7 diagnos...

show abstract

Section: Microbiological and Molecular Detection Of Ndm-1mentioning

confidence: 99%

An Irish outbreak of New Delhi metallo-β-lactamase (NDM)-1 carbapenemase-producing Enterobacteriaceae: increasing but unrecognized prevalence

O’Connor

Cormican

Boo

et al. 2016

Journal of Hospital Infection

View full text Add to dashboard Cite

show abstract

“…Among the primary roles of the clinical microbiologist are guidance and support of surgical teams, and selection of appropriate diagnostic investigations and antimicrobials, as warranted. 5 In this case, the recommended antibiotic treatment profile, based on susceptibility testing, included teicoplanin and vancomycin. However, the imperative for the surgical team was eradication of Actinomyces associated with bone prosthesis.…”

Section: Discussionmentioning

confidence: 99%

“…4 In response, use of molecular-based laboratory technologies has become relatively common, leading to more rapid microbial identification, susceptibility testing, reduction in empiric antimicrobial use, faster application of targeted therapies, and, overall, enhanced patient care. 5 Despite these advances, surgical practice can require decision-making with respect to treatment of nosocomial or procedure-related infections, often in the absence of laboratory data regarding the nature of causative organisms, whether those infections are monomicrobial or polymicrobial, and their relative sensitivities to available bacteriostatic or bacteriocidal agents. There is, therefore, an imperative that clinical and molecular…”

Section: Introductionmentioning

confidence: 99%

A commentary on the disparate perspectives of clinical microbiologists and surgeons

et al. 2014

Self Cite

View full text Add to dashboard Cite

Prosthetic joints and other orthopedic implants have improved quality of life for patients world-wide and the use of such devices is increasing. However, while infection rates subsequent to associated surgery are relatively low (<3%), the consequences of incidence are considerable, encompassing morbidity (including amputation) and mortality in addition to significant social and economic costs. Emphasis, therefore, has been placed on mitigating microbial risk, with clinical microbiologists and surgeons utilizing rapidly evolving molecular laboratory techniques in detection and diagnosis of infection, which still occurs despite sophisticated patient management. Multidisciplinary approaches are regularly adopted to achieve this. In this commentary, we describe an unusual case of Actinomyces infection in total hip arthroplasty and, in that context, describe the perspectives of the clinical microbiology and surgical teams and how they contrasted. More specifically, this case demonstrates an ad hoc approach to structured eradication of biofilms and intracellular bacteria related to biomaterials, as reflected in early usage of linezolid. This is a complex topic and, as described in this case, such accelerated treatment can be effective. This commentary focuses on the merits of such inadvisable use of potent antimicrobials amid the risk of diminishing valuable antimicrobial efficacy, albeit resulting in desirable patient outcomes.

show abstract

“…All colonies were identified using MALDI-ToF MS (Bruker Daltonics, Bremen, Germany) as described previously [20]. Confirmatory testing was performed by disk diffusion on all organisms that warranted further investigation (Thermo Scientific™ Oxoid™ Disks) using a disc dispenser; cefoxitin 30 μg (FOX), cefapime 30 μg (FED), ceftazidime 30 μg (CAZ) & ceftazidime-clavulanic acid 30/10 μg (CAZCV), cefotaxime 30 μg (CTX) & cefotaxime-clavulanic acid 30/10 μg (CTXCV), Muller Hinton agar, 0.5 McFarland inoculum; 35 +/−2 °C, ambient air, 16–28 h. Following incubation, the zone sizes of the cephalosporin disc to that of a cephalosporin plus clavulanic acid combination disc were compared to determine ESBL status.…”

Section: Methodsmentioning

confidence: 99%

The first occurrence of a CTX-M ESBL-producing Escherichia coli outbreak mediated by mother to neonate transmission in an Irish neonatal intensive care unit

et al. 2017

Self Cite

View full text Add to dashboard Cite

Background Escherichia coli (E. coli) comprise part of the normal vaginal microflora. Transfer from mother to neonate can occur during delivery resulting, sometimes, in neonatal bacterial disease. Here, we aim to report the first outbreak of CTX-M ESBL-producing E. coli with evidence of mother-to-neonate transmission in an Irish neonatal intensive care unit (NICU) followed by patient-to-patient transmission.MethodsInvestigation including molecular typing was conducted. Infection was defined by clinical and laboratory criteria and requirement for antimicrobial therapy with or without positive blood cultures. Colonisation was determined by isolation without relevant symptoms or indicators of infection.ResultsIndex case was an 8-day-old baby born at 34 weeks gestation who developed ESBL-producing E. coli infections at multiple body sites. Screening confirmed their mother as colonised with ESBL-producing E. coli. Five other neonates, in the NICU simultaneously with the index case, also tested positive. Of these, four were colonised while one neonate developed sepsis, requiring antimicrobial therapy. The second infected neonate’s mother was also colonised by ESBL-producing E. coli. Isolates from all eight positive patients (6 neonates, 2 mothers) were compared using pulsed-field gel electrophoresis (PFGE). Two distinct ESBL-producing strains were implicated, with evidence of transmission between mothers and neonates for both strains. All isolates were confirmed as CTX-M ESBL-producers. There were no deaths associated with the outbreak.ConclusionsResources were directed towards control interventions focused on hand hygiene and antimicrobial stewardship, which ultimately proved successful. Since this incident, all neonates admitted to the NICU have been screened for ESBL-producers and expectant mothers are screened at their first antenatal appointment. To date, there have been no further outbreaks.

show abstract

A commentary on the role of molecular technology and automation in clinical diagnostics

Cited by 18 publications

References 32 publications

An Irish outbreak of New Delhi metallo-β-lactamase (NDM)-1 carbapenemase-producing Enterobacteriaceae: increasing but unrecognized prevalence

An Irish outbreak of New Delhi metallo-β-lactamase (NDM)-1 carbapenemase-producing Enterobacteriaceae: increasing but unrecognized prevalence

A commentary on the disparate perspectives of clinical microbiologists and surgeons

The first occurrence of a CTX-M ESBL-producing Escherichia coli outbreak mediated by mother to neonate transmission in an Irish neonatal intensive care unit

Contact Info

Product

Resources

About