EH 3_2015

EUROPEAN HOSPITAL Vol 24 Issue 3/15 12 LABORATORY Matrix Assisted Laser Desorption Ionisation – Time of Flight How a UK NHS trust became one in the top 100 ‘Best Places to Work’ Identifying a single isolate in minutes A laboratory fit for a future decade Report: Mark Nicholls Dr Angharad Davies, Clinical Associate Professor and Honorary Consultant Microbiologist at Swansea University Medical School, highlighted the ben- efits and advantages for microbiol- ogy from this particular mass spec- trometry during the national meet- ing of the Association for Clinical Chemistry and Laboratory Medicine, in Cardiff this June. She outlined the clinical evaluation of the Bruker MALDI-TOF and Biotyper software system carried out by Public Health Wales (PHW) Swansea and Swansea University Medical School, when the system was first introduced. PHW Wales Microbiology Swansea was the first clinical microbiology labo- ratory in the UK to test the system in 2009. Following its success, the Fostering a collaborative way of working won the UK’s Dartford and Gravesham NHS Trust recognition as an elite public sector health- care employer, recently judged one of the top 100 ‘Best Places to Work’. The trust, led by chief executive Susan Acott, has created an energy- driven, patient-focused culture with- in the hospital, reflected by staff at all levels. This has been the driving force behind the creation of its new pathology service, led by pathology service general manager Chris Gunn and team. The hospital’s long-term vision has been to deliver an improved, cost effective and expanded diag- nostic service to the UK’s South East for at least the next 10 years. This involves a developing role as a trauma unit, alongside the increas- ingly diverse and complex demands system was introduced into rou- tine practice in PHW microbiology across Wales. In addition to a diagnostic evalu- ation, the Swansea team looked at MALDI-TOF’s ability to distin- guish between strains of the same bacterial species, with promising results. There have been a number of advances in this area since. The system has enhanced micro- biology in a number of ways. ‘MALDI-TOF, used with the software packages now available, allows very rapid and accurate identification of most bacterial species,’ she said. ‘It is much faster than methods that rely on an overnight culture step – a single isolate can be identified in minutes. The hardware is costly but the day-to-day consumable costs are very small compared to other meth- from GPs, with their multicultural and aging local population. The hospital required a long-term, cost efficient and automated solution, which had to be fully operational from the start. The team chose Beckman Coulter UK as its managed service partner. The main blood sciences sec- tion has been refurbished, and equipped with some of the latest instruments from Beckman Coulter as well as third party suppliers. ‘Together we are determined to cre- ate a substantially enhanced service in the region,’ said Chris Gunn. ‘Our 10-year plan is to drive ahead with increased turnaround time (TAT) efficiencies for existing customers, such as A&E and our local GPs, as well as competing for more external work.’ ods.’ In use, a laser beam is directed at a bacterial isolate suspended in a chemical matrix, Davies explained. The matrix lyses the cell wall and extracts the proteins, which become separated, and embedded in the dried crystal matrix. In practice, this means the bacterial colony is sus- pended in matrix solution and then spotted onto a credit-card-size metal target plate, which accommodates 96 such spots. The matrix absorbs the laser ener- gy and desorption results - a rapid explosive evaporation that carries the proteins into the gaseous phase. ‘As the matrix is acidic it ionises the proteins giving them a posi- tive charge. The resulting stream of ionised proteins is detected by the equipment, which generates a species-specific spectrum based on Automation drives expansion Currently, the lab processes 1.2 million biochemistry and 446,000 haematology tests a year, of which over 550,000 alone are from the Emergency Department (biochem- istry and haematology in total). Handling 2,000 tubes daily, the lab expects this to reach 7,000 by the end of the decade. Gunn also pre- dicts GP test demands will account for 50% of the lab’s total workloads. The lab currently handles 152,000 GP biochemistry requests annually. Even so, more than 92% of full blood count requests are completed in less than two hours. ‘And,’ he added, ‘we’ll be partnering with outside organisations to win further business.’ Within a newly built laboratory interior and an overall workflow ‘In addition, antibiotic susceptibil- ity testing has to be performed sepa- rately, meaning there is still another overnight culture step before defini- tive susceptibility results are avail- able.’ However, there is one other advantage, through the introduction of the All-Wales LIMS (Laboratory Information Management System), results entered in one site are acces- sible at all PHW lab sites. mass/charge ratio of its proteins,’ she said. ‘Clinicians can get a reli- able same-day identification of a cultured isolate instead of wait- ing for 24 hours. This can be very helpful in clinical management as it helps to indicate the likely clini- cal significance of the isolate, and antibiotic susceptibilities are much more predictable once the bacterial species is known.’ In terms of cost and efficiency for hospitals it allows better empirical antibiotic choices and, in the lab, reduces consumable costs consider- ably once the initial outlay has been made. ‘It has aided clinical decision- making which should result in bet- ter antibiotic choice for the patient,’ she said. ‘This leads to more effec- tive treatment more quickly. In Wales, all PHW microbiology labs now have access to MALDI- TOF. However, Davies stressed: ‘We need to bear in mind that the cost of the equipment means it is not present on every site – isolates now have to be transported in a timely fashion to a lab with MALDI-TOF, meaning that reliable and efficient transport arrangements need to be in place, and a reliable reporting system for results. design reflecting lean working prac- tices, Beckman Coulter installed its Power Processor, dynamic inlet and automated sample handling track. ‘We increasingly see the difference the new system makes to work- ing patterns and overall efficiency,’ Gunn noted. The automated track links chem- istry and immunoassay. Two AU5800 chemistry systems provide a total throughput of 6,700 tests per hour. This matches the track throughput and provides extra resilience for the electrolytes. The two Beckman Coulter DxI 800 immunoassay sys- tems are each able to run up to 400 tests an hour. Their speed and abil- ity to load reagents with the system running, without interrupting sam- ple processing, adds to productivity and efficiency. Samples are stored in the 3,060-capacity refrigerated storage unit. The Beckman Coulter REMISOL Advance data management system consolidates all the analysers and track into one standardised environ- ment for technical validation, pro- viding visibility and traceability of patient samples. Pre-analytic sample sorting is carried out by the com- pany’s high-speed AutoMate 2500, handling up to 1,200 samples per hour. From a single point of entry, it manages all tubes, from sample receipt to archiving. Workcell connectivity Beckman Coulter enhanced the lab’s haematology workflow efficiencies by connecting three UniCel DxH 800 analysers and a DxH Slidemaker Stainer (SMS) into an integrated workcell, the UniCel DxH 2401, with a single entry point for samples and compact, integral sample tracking system. With the latest version of the DxH software, it consolidates information for order entry, results review and quality control manage- ment. Performance, low review rates and first past accuracy in results report- ing are all driven by the company’s Automated Intelligent Morphology (AIM) technology, a multidimen- sional, high-definition flow cytomet- ric technology that improves analy- sis of abnormal specimens. The UniCel DxH 2401 configura- tion can analyse up to 300 samples an hour with a slide production rate of up to 140 smears per hour. The DxH workcell’s unique bi-directional sample transport system, automati- cally distributes samples between the analysers, reducing potential delays in the testing and reporting of results. The system also allows for critical STAT samples or body fluids to be added while the system is running, without interrupting rou- tine sample testing. ‘With connec- tivity, workloads are automatically distributed more evenly between the modules,’ Gunn explained. When trialled in Swansea, Wales, Matrix Assisted Laser Desorption Ionisation – Time of Flight (MALDI-TOF) demonstrated sufficient advantages over conventional methods to be introduced into routine practice. Dr Angharad Davies is Clinical Associate Professor and Honorary Consultant Microbiologist at Swansea University Medical School, where she leads the infec- tion and immunology group teaching for graduate entry students. Her key research interests include Cryptosporidium and mycobacterial infection. Haematology Workcell - UniCel DxH 2401

EH 3_2015

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