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Skladno s Pravilnikom o obveznem testiranju krvi se mora na vsaki enoti odvzete krvi, ob upoštevanju nacionalnih algoritmov, obvezno opraviti imunohematološka testiranja, ki predstavljajo prvi korak k varni transfuziji. Z namenom izpopolniti varnost in učinkovitost procesa tovrstnih testiranj, se je skozi čas uveljavila avtomatizacija postopka izvedbe z uporabo popolnoma avtomatiziranih analizatorjev. Ti bistveno prispevajo k časovno učinkovitejšemu delovnemu procesu, zmanjšanju možnosti človeških napak, manjši delovni obremenitvi laboratorija in nenazadnje k nižjim stroškom. Namen magistrskega dela je bil ovrednotiti učinkovitost in uporabnost popolnoma avtomatiziranega imunohematološkega analizatorja Ortho Vision® ter validirati uporabljeni analizni postopek s končnim podajanjem točnosti meritev, glede na referenčne rezultate, pridobljene s primerljivim avtomatiziranim analizatorjem Techno Twin. Vse raziskave in meritve smo opravili na Zavodu Republike Slovenije za transfuzijsko medicino (ZTM). V analizo smo vključili 1.246 vzorcev krvodajalcev, med katerimi je bilo tudi 73 posebnih vzorcev z že znanimi rezultati. Vsem vzorcem smo, glede na zastavljeno testno shemo, določili naslednje parametre: krvne skupine AB0, Rh, Kell, fenotip Rh, šibke različice antigena Rh D (Du), neposredni (direktni) in posredni (indirektni) Coombsov test ter prisotnost/odsotnost antigenov Duffy, Kidd in MNS. Ugotovili smo, da primerljivost rezultatov tako na nivoju meritev posameznih parametrov, kot tudi rezultatov vseh testiranj ni izpolnila kriterija sprejemljivosti, to je 99,98 %. Točnost rezultatov je bila namreč 92,29 %, predvsem zaradi nepridobitve ali pa neovrednotenja končnih rezultatov v 6,82 % primerov, kar je posledica visoko odzivne občutljivosti analizatorja na kakovost vzorcev, reagentov, reagenčnih kartic ali morebitnih človeških napak. Značilno razliko v primerjani uspešnosti pridobitve rezultatov z uporabljenimi testi na obeh analizatorjih smo potrdili z ustrezno statistično analizo. Medtem ko je bila diagnostična občutljivost presejalnega testa na prisotnost nespecifičnih protiteles v serumu dajalcev slabša (78,57 %), pa je bila njegova specifičnost boljša (94,74 %), v primerjavi z enakim testom, ki smo ga izvedli na referenčnem analizatorju Techno Twin. Na podlagi naših izsledkov lahko zaključimo, da je analizator Ortho Vision® primeren za potrebe laboratorija z visoko delovno obremenitvijo, saj omogoča večjo storilnost znotraj referenčnega časovnega okvira in je enostaven za uporabo ter vzdrževanje. Kljub temu pa za vpeljavo v diagnostični laboratorij za rutinsko testiranje krvi dajalcev potrebuje še nekaj dodatne optimizacije. Each donated unit of blood has to overcome the immunohematological testing procedure according to national algorithms, stipulated in Rules on the compulsory testing of human blood, which represents the first step to safe transfusion procedure. In order to improve safety and efficiency of testing, the technology focused on developing fully automated instruments, which contribute to improved efficiency of workflow, reduced rates of human errors, laboratory workload and lower costs. The master thesis aimed at evaluating the efficiency and applicability of a fully automated Ortho Vision® analyzer and validation of applied analytical methods. The validation was carried out by comparing the results obtained with the Ortho Vision® with a reference routinely used automated analyzer Techno Twin and assessed with parameter of accuracy. A comparative evaluation was performed at the Blood Transfusion Centre of Slovenia. A total of 1.246 blood samples taken from blood donors, 73 of them being treated as special cases with known results, were tested. Considering the test scheme the following analytical parameters were set up in parallel for the same blood samples on both analyzers: AB0, RhD and K blood typing, Rh phenotype typing, detection of weak D antigen (Du), direct and indirect Coombs test and presence/absence of antigens, belonging to Duffy, Kidd and MNS blood group systems. The required concordance rate between the standard and validated method was not reached neither at the level of a single analytical parameter nor at the level of overall results, resulting in an overall accuracy of 92,29 % (validation criteria: 99,98 %). This was mainly a consequence of unsuccessfully obtained or evaluated final results (6,82 %), which could be ascribed to the high sensitivity of analyzer or to a poor quality of samples, reagents or reagent cassettes or potential human errors. A significant difference in success rate of obtaining results with both systems was confirmed by relevant statistical analysis. The Ortho Vision® analyzer could offer higher diagnostic specificity (97,74 %) for antibody screening test but its diagnostic sensitivity was shown to be lower (78,57 %) when compared to the same test, carried out with the reference analyzer Techno Twin. Based on the outcomes we found the evaluated Ortho Vision® analyzer, to be applicable for use in a laboratory with a higher workload. In conclusion, we found that this analyzer is easy to use and maintain and can offer improved productivity – an ability to perform more work within a reference time period. Nevertheless, several optimizations should be addressed prior to implementing it in the laboratory for routine donor blood testing. |
